Просмотр исходного кода

ZOOKEEPER-78. added a high level protocol/feature - for easy Leader Election or exclusive Write Lock creation

git-svn-id: https://svn.apache.org/repos/asf/hadoop/zookeeper/trunk@768067 13f79535-47bb-0310-9956-ffa450edef68
Patrick D. Hunt 16 лет назад
Родитель
Сommit
579ad84545
36 измененных файлов с 4701 добавлено и 10 удалено
  1. 3 0
      CHANGES.txt
  2. 10 1
      build.xml
  3. 3 3
      src/c/Makefile.am
  4. 0 0
      src/c/include/zookeeper_log.h
  5. 1 1
      src/c/src/load_gen.c
  6. 1 1
      src/c/src/mt_adaptor.c
  7. 1 1
      src/c/src/zk_log.c
  8. 1 1
      src/c/src/zookeeper.c
  9. 2 2
      src/c/tests/Util.h
  10. 17 0
      src/recipes/README.txt
  11. 118 0
      src/recipes/build-recipes.xml
  12. 62 0
      src/recipes/build.xml
  13. 28 0
      src/recipes/lock/README.txt
  14. 144 0
      src/recipes/lock/build.xml
  15. 234 0
      src/recipes/lock/src/c/INSTALL
  16. 202 0
      src/recipes/lock/src/c/LICENSE
  17. 46 0
      src/recipes/lock/src/c/Makefile.am
  18. 28 0
      src/recipes/lock/src/c/README.txt
  19. 312 0
      src/recipes/lock/src/c/acinclude.m4
  20. 186 0
      src/recipes/lock/src/c/aminclude.am
  21. 1252 0
      src/recipes/lock/src/c/c-doc.Doxyfile
  22. 82 0
      src/recipes/lock/src/c/configure.ac
  23. 168 0
      src/recipes/lock/src/c/include/zoo_lock.h
  24. 396 0
      src/recipes/lock/src/c/src/zoo_lock.c
  25. 201 0
      src/recipes/lock/src/c/tests/TestClient.cc
  26. 114 0
      src/recipes/lock/src/c/tests/TestDriver.cc
  27. 30 0
      src/recipes/lock/src/c/tests/Util.cc
  28. 134 0
      src/recipes/lock/src/c/tests/Util.h
  29. 47 0
      src/recipes/lock/src/c/tests/zkServer.sh
  30. 38 0
      src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/LockListener.java
  31. 192 0
      src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ProtocolSupport.java
  32. 295 0
      src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/WriteLock.java
  33. 109 0
      src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ZNodeName.java
  34. 38 0
      src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ZooKeeperOperation.java
  35. 151 0
      src/recipes/lock/test/org/apache/zookeeper/recipes/lock/WriteLockTest.java
  36. 55 0
      src/recipes/lock/test/org/apache/zookeeper/recipes/lock/ZNodeNameTest.java

+ 3 - 0
CHANGES.txt

@@ -109,6 +109,9 @@ NEW FEATURES:
 
   ZOOKEEPER-371. jdiff documentation included in build/release (giri via phunt)
 
+  ZOOKEEPER-78. added a high level protocol/feature - for easy Leader
+  Election or exclusive Write Lock creation (mahadev via phunt)
+
 
 Release 3.1.0 - 2009-02-06
   

+ 10 - 1
build.xml

@@ -86,6 +86,7 @@
               location="${test.build.dir}/clover/reports"/>
 
     <property name="contrib.dir" value="${src.dir}/contrib"/>
+    <property name="recipes.dir" value="${src.dir}/recipes"/>
 
     <available property="clover.present"
                classname="com.cenqua.clover.CloverInstr"
@@ -429,6 +430,7 @@
       <mkdir dir="${dist.dir}"/>
       <mkdir dir="${dist.dir}/lib"/>
       <mkdir dir="${dist.dir}/contrib"/>
+      <mkdir dir="${dist.dir}/recipes"/>
       <mkdir dir="${dist.dir}/bin"/>
       <mkdir dir="${dist.dir}/docs"/>
       <mkdir dir="${dist.dir}/docs/jdiff"/>
@@ -444,6 +446,7 @@
         <property name="version" value="${version}"/>
         <property name="dist.dir" value="${dist.dir}"/>
         <fileset file="${contrib.dir}/build.xml"/>
+        <fileset file="${recipes.dir}/build.xml"/>
       </subant>  	
 
       <copy todir="${dist.dir}"> 
@@ -526,7 +529,7 @@
     <!-- ====================================================== -->
     <!-- Clean.  Delete the build files, and their directories  -->
     <!-- ====================================================== -->
-    <target name="clean" depends="clean-contrib"
+    <target name="clean" depends="clean-contrib,clean-recipes"
             description="Clean.  Delete the build files, and their directories">
       <delete dir="${build.dir}"/>
       <delete dir="${docs.src}/build"/>
@@ -551,6 +554,12 @@
       </subant>  	
     </target>
 
+   <target name="clean-recipes">
+     <subant target="clean">
+       <fileset file="${recipes.dir}/build.xml"/>
+     </subant>
+   </target>
+
     <!-- ====================================================== -->
     <!-- Run unit tests                                         -->
     <!-- ====================================================== -->

+ 3 - 3
src/c/Makefile.am

@@ -7,7 +7,7 @@ CXXFLAGS = -Wall -g
 
 LIB_LDFLAGS = -no-undefined -version-info 2
 
-pkginclude_HEADERS = include/zookeeper.h include/zookeeper_version.h include/recordio.h generated/zookeeper.jute.h
+pkginclude_HEADERS = include/zookeeper.h include/zookeeper_version.h include/zookeeper_log.h include/recordio.h generated/zookeeper.jute.h
 EXTRA_DIST=LICENSE
 
 HASHTABLE_SRC = src/hashtable/hashtable_itr.h src/hashtable/hashtable_itr.c \
@@ -16,10 +16,10 @@ HASHTABLE_SRC = src/hashtable/hashtable_itr.h src/hashtable/hashtable_itr.c \
 noinst_LTLIBRARIES = libhashtable.la
 libhashtable_la_SOURCES = $(HASHTABLE_SRC)
 
-COMMON_SRC = src/zookeeper.c include/zookeeper.h include/zookeeper_version.h \
+COMMON_SRC = src/zookeeper.c include/zookeeper.h include/zookeeper_version.h include/zookeeper_log.h\
     src/recordio.c include/recordio.h include/proto.h \
     src/zk_adaptor.h generated/zookeeper.jute.c \
-    src/zk_log.h src/zk_log.c src/zk_hashtable.h src/zk_hashtable.c
+    src/zookeeper_log.h src/zk_log.c src/zk_hashtable.h src/zk_hashtable.c
 
 noinst_LTLIBRARIES += libzkst.la
 libzkst_la_SOURCES =$(COMMON_SRC) src/st_adaptor.c

+ 0 - 0
src/c/src/zk_log.h → src/c/include/zookeeper_log.h


+ 1 - 1
src/c/src/load_gen.c

@@ -17,7 +17,7 @@
  */
 
 #include <zookeeper.h>
-#include "zk_log.h"
+#include "zookeeper_log.h"
 #include <errno.h>
 #include <pthread.h>
 #include <string.h>

+ 1 - 1
src/c/src/mt_adaptor.c

@@ -28,7 +28,7 @@
 #endif
 
 #include "zk_adaptor.h"
-#include "zk_log.h"
+#include "zookeeper_log.h"
 
 #include <stdlib.h>
 #include <stdio.h>

+ 1 - 1
src/c/src/zk_log.c

@@ -20,7 +20,7 @@
 #  define USE_STATIC_LIB
 #endif
 
-#include "zk_log.h"
+#include "zookeeper_log.h"
 #include <unistd.h>
 #include <stdarg.h>
 #include <time.h>

+ 1 - 1
src/c/src/zookeeper.c

@@ -28,7 +28,7 @@
 #include <zookeeper.jute.h>
 #include <proto.h>
 #include "zk_adaptor.h"
-#include "zk_log.h"
+#include "zookeeper_log.h"
 #include "zk_hashtable.h"
 
 #include <stdlib.h>

+ 2 - 2
src/c/tests/Util.h

@@ -23,7 +23,7 @@
 #include <vector>
 #include <string>
 
-#include "src/zk_log.h"
+#include "zookeeper_log.h"
 
 // number of elements in array
 #define COUNTOF(array) sizeof(array)/sizeof(array[0])
@@ -35,7 +35,7 @@
 #define CALL_REAL(sym,params) \
     __real_##sym params
 
-// must include "src/zk_log.h" to be able to use this macro
+// must include "src/zookeeper_log.h" to be able to use this macro
 #define TEST_TRACE(x) \
     log_message(ZOO_LOG_LEVEL_DEBUG,__LINE__,__func__,format_log_message x)
 

+ 17 - 0
src/recipes/README.txt

@@ -0,0 +1,17 @@
+1) This source directory contains various Zookeeper recipe implementations. 
+
+2) The recipe directory name should specify the name of the recipe you are implementing - eg. lock/.
+
+3) It would be great if you can provide both the java and c recipes for the zookeeper recipes.
+The c recipes go in to recipe-name/src/c and the java implementation goes into recipe-name/src/java.
+
+4) The recipes hold high standards like our zookeeper c/java libraries, so make sure that you include
+some unit testing with both the c and java recipe code.
+
+5) Also, please name your c client public methods as
+zkr_recipe-name_methodname
+(eg. zkr_lock_lock in lock/src/c)
+
+6) The various recipes are in ../../docs/recipes.html or
+../../docs/reciped.pdf. Also, this is not an exhaustive list by any chance.
+Zookeeper is used (and can be used) for more than what we have listed in the docs.

+ 118 - 0
src/recipes/build-recipes.xml

@@ -0,0 +1,118 @@
+<?xml version="1.0"?>
+
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+
+<!-- Imported by recipesb/*/build.xml files to share generic targets. -->
+
+<project name="zookeeperbuildrecipes">
+
+  <property name="name" value="${ant.project.name}"/>
+  <property name="root" value="${basedir}"/>
+
+  <property name="zk.root" location="${root}/../../../"/>
+
+  <property name="src.dir"  location="${root}/src/java"/>
+  <property name="src.test" location="${root}/src/test"/>
+
+  <property name="build.dir" location="${zk.root}/build/recipes/${name}"/>
+  <property name="build.classes" location="${build.dir}/classes"/>
+  <property name="build.test" location="${build.dir}/test"/>
+
+  <property name="javac.deprecation" value="on"/>
+  <property name="javac.debug" value="on"/>
+
+  <property name="build.encoding" value="ISO-8859-1"/>
+
+  <!-- to be overridden by sub-projects -->
+  <target name="check-recipes"/>
+  <target name="init-recipes"/>
+
+  <fileset id="lib.jars" dir="${root}" includes="lib/*.jar"/>
+
+  <path id="classpath">
+    <pathelement location="${build.classes}"/>
+    <fileset refid="lib.jars"/>
+    <pathelement location="${zk.root}/build/classes"/>
+    <fileset dir="${zk.root}/src/java/lib">
+      <include name="**/*.jar" />
+    </fileset>
+  </path>
+
+  <!-- ====================================================== -->
+  <!-- Stuff needed by all targets                            -->
+  <!-- ====================================================== -->
+  <target name="init" depends="check-recipes" unless="skip.recipes">
+    <echo message="recipes: ${name}"/>
+    <mkdir dir="${build.dir}"/>
+    <mkdir dir="${build.classes}"/>
+    <mkdir dir="${build.test}"/>
+    <antcall target="init-recipes"/>
+  </target>
+
+  <!-- ====================================================== -->
+  <!-- Compile a recipes files                                -->
+  <!-- ====================================================== -->
+  <target name="compile" depends="init" unless="skip.contrib">
+    <echo message="contrib: ${name}"/>
+
+    <javac
+     encoding="${build.encoding}"
+     srcdir="${src.dir}"
+     includes="**/*.java"
+     destdir="${build.classes}"
+     debug="${javac.debug}"
+     deprecation="${javac.deprecation}">
+      <classpath refid="classpath"/>
+    </javac>
+  </target>
+
+  <!-- ====================================================== -->
+  <!-- Make a recipes jar                                     -->
+  <!-- ====================================================== -->
+  <target name="jar" depends="compile" unless="skip.recipes">
+    <echo message="recipes: ${name}"/>
+    <jar
+      jarfile="${build.dir}/zookeeper-${version}-${name}.jar"
+      basedir="${build.classes}"      
+    />
+  </target>
+
+  <!-- ====================================================== -->
+  <!-- Package a recipes files                                -->
+  <!-- ====================================================== -->
+  <target name="package" depends="jar" unless="skip.recipes"> 
+    <echo message="recipes: ${name}"/>
+
+    <mkdir dir="${dist.dir}/recipes/${name}"/>
+    <copy todir="${dist.dir}/recipes/${name}" includeEmptyDirs="false"
+          flatten="true">
+      <fileset dir="${build.dir}">
+        <include name="zookeeper-${version}-${name}.jar" />
+      </fileset>
+    </copy>
+  </target>
+
+  <!-- ================================================================== -->
+  <!-- Clean.  Delete the build files, and their directories              -->
+  <!-- ================================================================== -->
+  <target name="clean">
+    <echo message="recipes: ${name}"/>
+    <delete dir="${build.dir}"/>
+  </target>
+
+</project>

+ 62 - 0
src/recipes/build.xml

@@ -0,0 +1,62 @@
+<?xml version="1.0"?>
+
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+
+<project name="zookeeperrecipes" default="compile" basedir=".">
+  
+  <!-- In case one of the contrib subdirectories -->
+  <!-- fails the build or test targets and you cannot fix it: -->
+  <!-- Then add to fileset: excludes="badcontrib/build.xml" -->
+
+  <!-- ====================================================== -->
+  <!-- Compile contribs.                                      -->
+  <!-- ====================================================== -->
+  <target name="compile">
+    <subant target="jar">
+      <fileset dir="." includes="*/build.xml"/>
+    </subant>
+  </target>
+  
+  <!-- ====================================================== -->
+  <!-- Package contrib jars.                                  -->
+  <!-- ====================================================== -->
+  <target name="package">
+    <subant target="package">
+      <fileset dir="." includes="*/build.xml"/>
+    </subant>
+  </target>
+  
+  <!-- ====================================================== -->
+  <!-- Test all the contribs.                               -->
+  <!-- ====================================================== -->
+  <target name="test">
+    <subant target="test">
+      <fileset dir="." includes="*/build.xml"/>
+    </subant>
+  </target>
+  
+  <!-- ====================================================== -->
+  <!-- Clean all the contribs.                              -->
+  <!-- ====================================================== -->
+  <target name="clean">
+    <subant target="clean">
+      <fileset dir="." includes="*/build.xml"/>
+    </subant>
+  </target>
+
+</project>

+ 28 - 0
src/recipes/lock/README.txt

@@ -0,0 +1,28 @@
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+
+1) This lock interface recipe implements the lock recipe
+mentioned in ../../../docs/recipes.[html,pdf].
+
+2) To compile the lock java recipe you can just run ant jar from 
+this directory. For compiling the c libarary go to src/c and read
+the INSTALLATION instructions. 
+Please report any bugs on the jira 
+
+http://issues.apache.org/jira/browse/ZOOKEEPER
+
+  

+ 144 - 0
src/recipes/lock/build.xml

@@ -0,0 +1,144 @@
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+
+<project name="lock" default="jar">
+  <import file="../build-recipes.xml"/>
+    <property name="test.main.classes" value="${zk.root}/build/testclasses"/>
+    <property name="test.build.dir" value="${build.test}" />
+    <property name="test.src.dir" value="test"/>
+    <property name="test.log.dir" value="${test.build.dir}/logs" />
+    <property name="test.data.dir" value="${test.build.dir}/data" />
+    <property name="test.data.upgrade.dir" value="${test.data.dir}/upgrade" />
+    <property name="test.tmp.dir" value="${test.build.dir}/tmp" />
+    <property name="test.output" value="no" />
+    <property name="test.timeout" value="900000" />
+    <property name="test.junit.output.format" value="plain" />
+    <property name="test.junit.fork.mode" value="perTest" />
+    <property name="test.junit.printsummary" value="yes" />
+    <property name="test.junit.haltonfailure" value="no" />
+    <property name="test.junit.maxmem" value="512m" />
+
+  
+  <available classname="org.apache.zookeeper.ZooKeeperMain"
+             classpathref="classpath"
+             property="mainIsCompiled"/>
+
+  <target name="checkMainCompiled" unless="mainIsCompiled">
+    <fail message="ZooKeeper main must first be compiled (toplevel build.xml)"/>
+  </target>
+
+  <target name="versionedjarname" if="version">
+    <property name="jarname"
+              value="${build.dir}/zookeeper-${version}-recipes-${name}.jar"/>
+  </target>
+
+  <target name="unversionedjarname" unless="version">
+    <property name="jarname"
+              value="${build.dir}/zookeeper-dev-recipes-${name}.jar"/>
+  </target>
+
+  <target name="setjarname" depends="versionedjarname, unversionedjarname"/>
+
+  <!-- Override jar target to specify main class -->
+  <target name="jar" depends="checkMainCompiled, setjarname, compile">
+    <echo message="recipes: ${name}"/>
+
+    <jar jarfile="${jarname}">
+      <fileset file="${zk.root}/LICENSE.txt" />
+      <fileset dir="${build.classes}"/>
+      <fileset dir="${build.test}"/>
+    </jar>
+  </target>
+
+	<target name="test" depends="compile-test,test-init,test-category,junit.run" />
+
+	<target name="compile-test" depends="compile">
+  		<property name="target.jdk" value="${ant.java.version}" />	
+		<property name="src.test.local" location="${basedir}/test" />
+		<mkdir dir="${build.test}"/>
+		<javac srcdir="${src.test.local}" 
+			destdir="${build.test}" 
+			target="${target.jdk}" 
+			debug="on" >
+			<classpath refid="classpath" />
+                        <classpath>
+                        <pathelement path="${test.main.classes}"/>
+                        </classpath>
+		</javac>
+	</target>
+	
+    <target name="test-init" depends="jar,compile-test">
+        <delete dir="${test.log.dir}" />
+        <delete dir="${test.tmp.dir}" />
+        <delete dir="${test.data.dir}" />
+        <mkdir dir="${test.log.dir}" />
+        <mkdir dir="${test.tmp.dir}" />
+        <mkdir dir="${test.data.dir}" />
+    </target>
+
+	<target name="test-category">
+         <property name="test.category" value=""/>
+    </target>
+
+	<target name="junit.run">
+		<echo message="${test.src.dir}" />
+        <junit showoutput="${test.output}"
+               printsummary="${test.junit.printsummary}"
+               haltonfailure="${test.junit.haltonfailure}"
+               fork="yes"
+               forkmode="${test.junit.fork.mode}"
+               maxmemory="${test.junit.maxmem}"
+               dir="${basedir}" timeout="${test.timeout}"
+               errorProperty="tests.failed" failureProperty="tests.failed">
+          <sysproperty key="build.test.dir" value="${test.tmp.dir}" />
+          <sysproperty key="test.data.dir" value="${test.data.dir}" />
+          <sysproperty key="log4j.configuration"
+                    value="file:${basedir}/conf/log4j.properties" />
+          <classpath refid="classpath"/>
+          <classpath>
+             <pathelement path="${build.test}" />
+             <pathelement path="${test.main.classes}"/>
+          </classpath>
+          <formatter type="${test.junit.output.format}" />
+          <batchtest todir="${test.log.dir}" unless="testcase">
+              <fileset dir="${test.src.dir}"
+                     includes="**/*${test.category}Test.java"/>
+          </batchtest>
+          <batchtest todir="${test.log.dir}" if="testcase">
+              <fileset dir="${test.src.dir}" includes="**/${testcase}.java"/>
+          </batchtest>
+       </junit>
+            <fail if="tests.failed">Tests failed!</fail>
+    </target>
+
+  <target name="package" depends="jar, zookeeperbuildrecipes.package"
+          unless="skip.recipes">
+
+    <copy file="${basedir}/build.xml" todir="${dist.dir}/recipes/${name}"/>
+
+    <mkdir dir="${dist.dir}/recipes/${name}/test"/>
+    <copy todir="${dist.dir}/recipes/${name}/test">
+      <fileset dir="${basedir}/test"/>
+    </copy>
+    <mkdir dir="${dist.dir}/recipes/${name}/src"/>
+    <copy todir="${dist.dir}/recipes/${name}/src">
+      <fileset dir="${basedir}/src"/>
+    </copy>
+  </target>
+
+</project>
+

+ 234 - 0
src/recipes/lock/src/c/INSTALL

@@ -0,0 +1,234 @@
+Installation Instructions
+*************************
+
+Copyright (C) 1994, 1995, 1996, 1999, 2000, 2001, 2002, 2004, 2005,
+2006 Free Software Foundation, Inc.
+
+This file is free documentation; the Free Software Foundation gives
+unlimited permission to copy, distribute and modify it.
+
+Basic Installation
+==================
+
+Briefly, the shell commands `./configure; make; make install' should
+configure, build, and install this package.  The following
+more-detailed instructions are generic; see the `README' file for
+instructions specific to this package.
+
+   The `configure' shell script attempts to guess correct values for
+various system-dependent variables used during compilation.  It uses
+those values to create a `Makefile' in each directory of the package.
+It may also create one or more `.h' files containing system-dependent
+definitions.  Finally, it creates a shell script `config.status' that
+you can run in the future to recreate the current configuration, and a
+file `config.log' containing compiler output (useful mainly for
+debugging `configure').
+
+   It can also use an optional file (typically called `config.cache'
+and enabled with `--cache-file=config.cache' or simply `-C') that saves
+the results of its tests to speed up reconfiguring.  Caching is
+disabled by default to prevent problems with accidental use of stale
+cache files.
+
+   If you need to do unusual things to compile the package, please try
+to figure out how `configure' could check whether to do them, and mail
+diffs or instructions to the address given in the `README' so they can
+be considered for the next release.  If you are using the cache, and at
+some point `config.cache' contains results you don't want to keep, you
+may remove or edit it.
+
+   The file `configure.ac' (or `configure.in') is used to create
+`configure' by a program called `autoconf'.  You need `configure.ac' if
+you want to change it or regenerate `configure' using a newer version
+of `autoconf'.
+
+The simplest way to compile this package is:
+
+  1. `cd' to the directory containing the package's source code and type
+     `./configure' to configure the package for your system.
+
+     Running `configure' might take a while.  While running, it prints
+     some messages telling which features it is checking for.
+
+  2. Type `make' to compile the package.
+
+  3. Optionally, type `make check' to run any self-tests that come with
+     the package.
+
+  4. Type `make install' to install the programs and any data files and
+     documentation.
+
+  5. You can remove the program binaries and object files from the
+     source code directory by typing `make clean'.  To also remove the
+     files that `configure' created (so you can compile the package for
+     a different kind of computer), type `make distclean'.  There is
+     also a `make maintainer-clean' target, but that is intended mainly
+     for the package's developers.  If you use it, you may have to get
+     all sorts of other programs in order to regenerate files that came
+     with the distribution.
+
+Compilers and Options
+=====================
+
+Some systems require unusual options for compilation or linking that the
+`configure' script does not know about.  Run `./configure --help' for
+details on some of the pertinent environment variables.
+
+   You can give `configure' initial values for configuration parameters
+by setting variables in the command line or in the environment.  Here
+is an example:
+
+     ./configure CC=c99 CFLAGS=-g LIBS=-lposix
+
+   *Note Defining Variables::, for more details.
+
+Compiling For Multiple Architectures
+====================================
+
+You can compile the package for more than one kind of computer at the
+same time, by placing the object files for each architecture in their
+own directory.  To do this, you can use GNU `make'.  `cd' to the
+directory where you want the object files and executables to go and run
+the `configure' script.  `configure' automatically checks for the
+source code in the directory that `configure' is in and in `..'.
+
+   With a non-GNU `make', it is safer to compile the package for one
+architecture at a time in the source code directory.  After you have
+installed the package for one architecture, use `make distclean' before
+reconfiguring for another architecture.
+
+Installation Names
+==================
+
+By default, `make install' installs the package's commands under
+`/usr/local/bin', include files under `/usr/local/include', etc.  You
+can specify an installation prefix other than `/usr/local' by giving
+`configure' the option `--prefix=PREFIX'.
+
+   You can specify separate installation prefixes for
+architecture-specific files and architecture-independent files.  If you
+pass the option `--exec-prefix=PREFIX' to `configure', the package uses
+PREFIX as the prefix for installing programs and libraries.
+Documentation and other data files still use the regular prefix.
+
+   In addition, if you use an unusual directory layout you can give
+options like `--bindir=DIR' to specify different values for particular
+kinds of files.  Run `configure --help' for a list of the directories
+you can set and what kinds of files go in them.
+
+   If the package supports it, you can cause programs to be installed
+with an extra prefix or suffix on their names by giving `configure' the
+option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.
+
+Optional Features
+=================
+
+Some packages pay attention to `--enable-FEATURE' options to
+`configure', where FEATURE indicates an optional part of the package.
+They may also pay attention to `--with-PACKAGE' options, where PACKAGE
+is something like `gnu-as' or `x' (for the X Window System).  The
+`README' should mention any `--enable-' and `--with-' options that the
+package recognizes.
+
+   For packages that use the X Window System, `configure' can usually
+find the X include and library files automatically, but if it doesn't,
+you can use the `configure' options `--x-includes=DIR' and
+`--x-libraries=DIR' to specify their locations.
+
+Specifying the System Type
+==========================
+
+There may be some features `configure' cannot figure out automatically,
+but needs to determine by the type of machine the package will run on.
+Usually, assuming the package is built to be run on the _same_
+architectures, `configure' can figure that out, but if it prints a
+message saying it cannot guess the machine type, give it the
+`--build=TYPE' option.  TYPE can either be a short name for the system
+type, such as `sun4', or a canonical name which has the form:
+
+     CPU-COMPANY-SYSTEM
+
+where SYSTEM can have one of these forms:
+
+     OS KERNEL-OS
+
+   See the file `config.sub' for the possible values of each field.  If
+`config.sub' isn't included in this package, then this package doesn't
+need to know the machine type.
+
+   If you are _building_ compiler tools for cross-compiling, you should
+use the option `--target=TYPE' to select the type of system they will
+produce code for.
+
+   If you want to _use_ a cross compiler, that generates code for a
+platform different from the build platform, you should specify the
+"host" platform (i.e., that on which the generated programs will
+eventually be run) with `--host=TYPE'.
+
+Sharing Defaults
+================
+
+If you want to set default values for `configure' scripts to share, you
+can create a site shell script called `config.site' that gives default
+values for variables like `CC', `cache_file', and `prefix'.
+`configure' looks for `PREFIX/share/config.site' if it exists, then
+`PREFIX/etc/config.site' if it exists.  Or, you can set the
+`CONFIG_SITE' environment variable to the location of the site script.
+A warning: not all `configure' scripts look for a site script.
+
+Defining Variables
+==================
+
+Variables not defined in a site shell script can be set in the
+environment passed to `configure'.  However, some packages may run
+configure again during the build, and the customized values of these
+variables may be lost.  In order to avoid this problem, you should set
+them in the `configure' command line, using `VAR=value'.  For example:
+
+     ./configure CC=/usr/local2/bin/gcc
+
+causes the specified `gcc' to be used as the C compiler (unless it is
+overridden in the site shell script).
+
+Unfortunately, this technique does not work for `CONFIG_SHELL' due to
+an Autoconf bug.  Until the bug is fixed you can use this workaround:
+
+     CONFIG_SHELL=/bin/bash /bin/bash ./configure CONFIG_SHELL=/bin/bash
+
+`configure' Invocation
+======================
+
+`configure' recognizes the following options to control how it operates.
+
+`--help'
+`-h'
+     Print a summary of the options to `configure', and exit.
+
+`--version'
+`-V'
+     Print the version of Autoconf used to generate the `configure'
+     script, and exit.
+
+`--cache-file=FILE'
+     Enable the cache: use and save the results of the tests in FILE,
+     traditionally `config.cache'.  FILE defaults to `/dev/null' to
+     disable caching.
+
+`--config-cache'
+`-C'
+     Alias for `--cache-file=config.cache'.
+
+`--quiet'
+`--silent'
+`-q'
+     Do not print messages saying which checks are being made.  To
+     suppress all normal output, redirect it to `/dev/null' (any error
+     messages will still be shown).
+
+`--srcdir=DIR'
+     Look for the package's source code in directory DIR.  Usually
+     `configure' can determine that directory automatically.
+
+`configure' also accepts some other, not widely useful, options.  Run
+`configure --help' for more details.
+

+ 202 - 0
src/recipes/lock/src/c/LICENSE

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

+ 46 - 0
src/recipes/lock/src/c/Makefile.am

@@ -0,0 +1,46 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+include $(top_srcdir)/aminclude.am
+
+AM_CFLAGS = -Wall -fPIC -I${ZOOKEEPER_PATH}/include -I${ZOOKEEPER_PATH}/generated \
+  -I$(top_srcdir)/include -I/usr/include 
+AM_CPPFLAGS = -Wall -I${ZOOKEEPER_PATH}/include -I${ZOOKEEPER_PATH}/generated\
+  -I${top_srcdir}/include -I/usr/include
+EXTRA_DIST = LICENSE
+lib_LTLIBRARIES = libzoolock.la
+libzoolock_la_SOURCES = src/zoo_lock.c include/zoo_lock.h
+libzoolock_la_CPPFLAGS = -DDLOPEN_MODULE
+libzoolock_la_LDFLAGS = -version-info 0:1:0
+
+#run the tests now
+
+TEST_SOURCES = tests/TestDriver.cc tests/TestClient.cc tests/Util.cc 
+
+
+check_PROGRAMS = zklocktest
+nodist_zklocktest_SOURCES = ${TEST_SOURCES}
+zklocktest_LDADD =  ${ZOOKEEPER_LD} libzoolock.la -lpthread  ${CPPUNIT_LIBS}
+zklocktest_CXXFLAGS = -DUSE_STATIC_LIB ${CPPUNIT_CFLAGS}
+
+run-check: check
+	./zklocktest ${TEST_OPTIONS}
+
+clean-local: clean-check
+	${RM} ${DX_CLEANFILES}
+
+clean-check:
+	${RM} ${nodist_zklocktest_OBJECTS} 

+ 28 - 0
src/recipes/lock/src/c/README.txt

@@ -0,0 +1,28 @@
+                     Zookeeper C lock client library 
+
+
+INSTALLATION
+
+If you're building the client from a source checkout you need to
+follow the steps outlined below. If you're building from a release
+tar downloaded from Apache please skip to step 2.
+
+1) make sure that you compile the main zookeeper c client library.
+ 
+2) change directory to src/recipes/lock/src/c 
+    and do a "autoreconf -if" to bootstrap
+   autoconf, automake and libtool. Please make sure you have autoconf
+   version 2.59 or greater installed.
+3) do a "./configure [OPTIONS]" to generate the makefile. See INSTALL
+   for general information about running configure.
+
+4) do a "make" or "make install" to build the libraries and install them. 
+   Alternatively, you can also build and run a unit test suite (and
+   you probably should).  Please make sure you have cppunit-1.10.x or
+   higher installed before you execute step 4.  Once ./configure has
+   finished, do a "make run-check". It will build the libraries, build
+   the tests and run them.
+5) to generate doxygen documentation do a "make doxygen-doc". All
+   documentations will be placed to a new subfolder named docs. By
+   default only HTML documentation is generated.  For information on
+   other document formats please use "./configure --help"

+ 312 - 0
src/recipes/lock/src/c/acinclude.m4

@@ -0,0 +1,312 @@
+# This file is part of Autoconf.                       -*- Autoconf -*-
+
+# Copyright (C) 2004 Oren Ben-Kiki
+# This file is distributed under the same terms as the Autoconf macro files.
+
+# Generate automatic documentation using Doxygen. Works in concert with the
+# aminclude.m4 file and a compatible doxygen configuration file. Defines the
+# following public macros:
+#
+# DX_???_FEATURE(ON|OFF) - control the default setting fo a Doxygen feature.
+# Supported features are 'DOXYGEN' itself, 'DOT' for generating graphics,
+# 'HTML' for plain HTML, 'CHM' for compressed HTML help (for MS users), 'CHI'
+# for generating a seperate .chi file by the .chm file, and 'MAN', 'RTF',
+# 'XML', 'PDF' and 'PS' for the appropriate output formats. The environment
+# variable DOXYGEN_PAPER_SIZE may be specified to override the default 'a4wide'
+# paper size.
+#
+# By default, HTML, PDF and PS documentation is generated as this seems to be
+# the most popular and portable combination. MAN pages created by Doxygen are
+# usually problematic, though by picking an appropriate subset and doing some
+# massaging they might be better than nothing. CHM and RTF are specific for MS
+# (note that you can't generate both HTML and CHM at the same time). The XML is
+# rather useless unless you apply specialized post-processing to it.
+#
+# The macro mainly controls the default state of the feature. The use can
+# override the default by specifying --enable or --disable. The macros ensure
+# that contradictory flags are not given (e.g., --enable-doxygen-html and
+# --enable-doxygen-chm, --enable-doxygen-anything with --disable-doxygen, etc.)
+# Finally, each feature will be automatically disabled (with a warning) if the
+# required programs are missing.
+#
+# Once all the feature defaults have been specified, call DX_INIT_DOXYGEN with
+# the following parameters: a one-word name for the project for use as a
+# filename base etc., an optional configuration file name (the default is
+# 'Doxyfile', the same as Doxygen's default), and an optional output directory
+# name (the default is 'doxygen-doc').
+
+## ----------##
+## Defaults. ##
+## ----------##
+
+DX_ENV=""
+AC_DEFUN([DX_FEATURE_doc],  ON)
+AC_DEFUN([DX_FEATURE_dot],  ON)
+AC_DEFUN([DX_FEATURE_man],  OFF)
+AC_DEFUN([DX_FEATURE_html], ON)
+AC_DEFUN([DX_FEATURE_chm],  OFF)
+AC_DEFUN([DX_FEATURE_chi],  OFF)
+AC_DEFUN([DX_FEATURE_rtf],  OFF)
+AC_DEFUN([DX_FEATURE_xml],  OFF)
+AC_DEFUN([DX_FEATURE_pdf],  ON)
+AC_DEFUN([DX_FEATURE_ps],   ON)
+
+## --------------- ##
+## Private macros. ##
+## --------------- ##
+
+# DX_ENV_APPEND(VARIABLE, VALUE)
+# ------------------------------
+# Append VARIABLE="VALUE" to DX_ENV for invoking doxygen.
+AC_DEFUN([DX_ENV_APPEND], [AC_SUBST([DX_ENV], ["$DX_ENV $1='$2'"])])
+
+# DX_DIRNAME_EXPR
+# ---------------
+# Expand into a shell expression prints the directory part of a path.
+AC_DEFUN([DX_DIRNAME_EXPR],
+         [[expr ".$1" : '\(\.\)[^/]*$' \| "x$1" : 'x\(.*\)/[^/]*$']])
+
+# DX_IF_FEATURE(FEATURE, IF-ON, IF-OFF)
+# -------------------------------------
+# Expands according to the M4 (static) status of the feature.
+AC_DEFUN([DX_IF_FEATURE], [ifelse(DX_FEATURE_$1, ON, [$2], [$3])])
+
+# DX_REQUIRE_PROG(VARIABLE, PROGRAM)
+# ----------------------------------
+# Require the specified program to be found for the DX_CURRENT_FEATURE to work.
+AC_DEFUN([DX_REQUIRE_PROG], [
+AC_PATH_TOOL([$1], [$2])
+if test "$DX_FLAG_$[DX_CURRENT_FEATURE$$1]" = 1; then
+    AC_MSG_WARN([$2 not found - will not DX_CURRENT_DESCRIPTION])
+    AC_SUBST([DX_FLAG_]DX_CURRENT_FEATURE, 0)
+fi
+])
+
+# DX_TEST_FEATURE(FEATURE)
+# ------------------------
+# Expand to a shell expression testing whether the feature is active.
+AC_DEFUN([DX_TEST_FEATURE], [test "$DX_FLAG_$1" = 1])
+
+# DX_CHECK_DEPEND(REQUIRED_FEATURE, REQUIRED_STATE)
+# -------------------------------------------------
+# Verify that a required features has the right state before trying to turn on
+# the DX_CURRENT_FEATURE.
+AC_DEFUN([DX_CHECK_DEPEND], [
+test "$DX_FLAG_$1" = "$2" \
+|| AC_MSG_ERROR([doxygen-DX_CURRENT_FEATURE ifelse([$2], 1,
+                            requires, contradicts) doxygen-DX_CURRENT_FEATURE])
+])
+
+# DX_CLEAR_DEPEND(FEATURE, REQUIRED_FEATURE, REQUIRED_STATE)
+# ----------------------------------------------------------
+# Turn off the DX_CURRENT_FEATURE if the required feature is off.
+AC_DEFUN([DX_CLEAR_DEPEND], [
+test "$DX_FLAG_$1" = "$2" || AC_SUBST([DX_FLAG_]DX_CURRENT_FEATURE, 0)
+])
+
+# DX_FEATURE_ARG(FEATURE, DESCRIPTION,
+#                CHECK_DEPEND, CLEAR_DEPEND,
+#                REQUIRE, DO-IF-ON, DO-IF-OFF)
+# --------------------------------------------
+# Parse the command-line option controlling a feature. CHECK_DEPEND is called
+# if the user explicitly turns the feature on (and invokes DX_CHECK_DEPEND),
+# otherwise CLEAR_DEPEND is called to turn off the default state if a required
+# feature is disabled (using DX_CLEAR_DEPEND). REQUIRE performs additional
+# requirement tests (DX_REQUIRE_PROG). Finally, an automake flag is set and
+# DO-IF-ON or DO-IF-OFF are called according to the final state of the feature.
+AC_DEFUN([DX_ARG_ABLE], [
+    AC_DEFUN([DX_CURRENT_FEATURE], [$1])
+    AC_DEFUN([DX_CURRENT_DESCRIPTION], [$2])
+    AC_ARG_ENABLE(doxygen-$1,
+                  [AS_HELP_STRING(DX_IF_FEATURE([$1], [--disable-doxygen-$1],
+                                                      [--enable-doxygen-$1]),
+                                  DX_IF_FEATURE([$1], [don't $2], [$2]))],
+                  [
+case "$enableval" in
+#(
+y|Y|yes|Yes|YES)
+    AC_SUBST([DX_FLAG_$1], 1)
+    $3
+;; #(
+n|N|no|No|NO)
+    AC_SUBST([DX_FLAG_$1], 0)
+;; #(
+*)
+    AC_MSG_ERROR([invalid value '$enableval' given to doxygen-$1])
+;;
+esac
+], [
+AC_SUBST([DX_FLAG_$1], [DX_IF_FEATURE([$1], 1, 0)])
+$4
+])
+if DX_TEST_FEATURE([$1]); then
+    $5
+    :
+fi
+if DX_TEST_FEATURE([$1]); then
+    AM_CONDITIONAL(DX_COND_$1, :)
+    $6
+    :
+else
+    AM_CONDITIONAL(DX_COND_$1, false)
+    $7
+    :
+fi
+])
+
+## -------------- ##
+## Public macros. ##
+## -------------- ##
+
+# DX_XXX_FEATURE(DEFAULT_STATE)
+# -----------------------------
+AC_DEFUN([DX_DOXYGEN_FEATURE], [AC_DEFUN([DX_FEATURE_doc],  [$1])])
+AC_DEFUN([DX_MAN_FEATURE],     [AC_DEFUN([DX_FEATURE_man],  [$1])])
+AC_DEFUN([DX_HTML_FEATURE],    [AC_DEFUN([DX_FEATURE_html], [$1])])
+AC_DEFUN([DX_CHM_FEATURE],     [AC_DEFUN([DX_FEATURE_chm],  [$1])])
+AC_DEFUN([DX_CHI_FEATURE],     [AC_DEFUN([DX_FEATURE_chi],  [$1])])
+AC_DEFUN([DX_RTF_FEATURE],     [AC_DEFUN([DX_FEATURE_rtf],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_PDF_FEATURE],     [AC_DEFUN([DX_FEATURE_pdf],  [$1])])
+AC_DEFUN([DX_PS_FEATURE],      [AC_DEFUN([DX_FEATURE_ps],   [$1])])
+
+# DX_INIT_DOXYGEN(PROJECT, [CONFIG-FILE], [OUTPUT-DOC-DIR])
+# ---------------------------------------------------------
+# PROJECT also serves as the base name for the documentation files.
+# The default CONFIG-FILE is "Doxyfile" and OUTPUT-DOC-DIR is "doxygen-doc".
+AC_DEFUN([DX_INIT_DOXYGEN], [
+
+# Files:
+AC_SUBST([DX_PROJECT], [$1])
+AC_SUBST([DX_CONFIG], [ifelse([$2], [], Doxyfile, [$2])])
+AC_SUBST([DX_DOCDIR], [ifelse([$3], [], doxygen-doc, [$3])])
+
+# Environment variables used inside doxygen.cfg:
+DX_ENV_APPEND(SRCDIR, $srcdir)
+DX_ENV_APPEND(PROJECT, $DX_PROJECT)
+DX_ENV_APPEND(DOCDIR, $DX_DOCDIR)
+DX_ENV_APPEND(VERSION, $PACKAGE_VERSION)
+
+# Doxygen itself:
+DX_ARG_ABLE(doc, [generate any doxygen documentation],
+            [],
+            [],
+            [DX_REQUIRE_PROG([DX_DOXYGEN], doxygen)
+             DX_REQUIRE_PROG([DX_PERL], perl)],
+            [DX_ENV_APPEND(PERL_PATH, $DX_PERL)])
+
+# Dot for graphics:
+DX_ARG_ABLE(dot, [generate graphics for doxygen documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_DOT], dot)],
+            [DX_ENV_APPEND(HAVE_DOT, YES)
+             DX_ENV_APPEND(DOT_PATH, [`DX_DIRNAME_EXPR($DX_DOT)`])],
+            [DX_ENV_APPEND(HAVE_DOT, NO)])
+
+# Man pages generation:
+DX_ARG_ABLE(man, [generate doxygen manual pages],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_MAN, YES)],
+            [DX_ENV_APPEND(GENERATE_MAN, NO)])
+
+# RTF file generation:
+DX_ARG_ABLE(rtf, [generate doxygen RTF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_RTF, YES)],
+            [DX_ENV_APPEND(GENERATE_RTF, NO)])
+
+# XML file generation:
+DX_ARG_ABLE(xml, [generate doxygen XML documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_XML, YES)],
+            [DX_ENV_APPEND(GENERATE_XML, NO)])
+
+# (Compressed) HTML help generation:
+DX_ARG_ABLE(chm, [generate doxygen compressed HTML help documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_HHC], hhc)],
+            [DX_ENV_APPEND(HHC_PATH, $DX_HHC)
+             DX_ENV_APPEND(GENERATE_HTML, YES)
+             DX_ENV_APPEND(GENERATE_HTMLHELP, YES)],
+            [DX_ENV_APPEND(GENERATE_HTMLHELP, NO)])
+
+# Seperate CHI file generation.
+DX_ARG_ABLE(chi, [generate doxygen seperate compressed HTML help index file],
+            [DX_CHECK_DEPEND(chm, 1)],
+            [DX_CLEAR_DEPEND(chm, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_CHI, YES)],
+            [DX_ENV_APPEND(GENERATE_CHI, NO)])
+
+# Plain HTML pages generation:
+DX_ARG_ABLE(html, [generate doxygen plain HTML documentation],
+            [DX_CHECK_DEPEND(doc, 1) DX_CHECK_DEPEND(chm, 0)],
+            [DX_CLEAR_DEPEND(doc, 1) DX_CLEAR_DEPEND(chm, 0)],
+            [],
+            [DX_ENV_APPEND(GENERATE_HTML, YES)],
+            [DX_TEST_FEATURE(chm) || DX_ENV_APPEND(GENERATE_HTML, NO)])
+
+# PostScript file generation:
+DX_ARG_ABLE(ps, [generate doxygen PostScript documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_LATEX], latex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_DVIPS], dvips)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# PDF file generation:
+DX_ARG_ABLE(pdf, [generate doxygen PDF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_PDFLATEX], pdflatex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# LaTeX generation for PS and/or PDF:
+if DX_TEST_FEATURE(ps) || DX_TEST_FEATURE(pdf); then
+    AM_CONDITIONAL(DX_COND_latex, :)
+    DX_ENV_APPEND(GENERATE_LATEX, YES)
+else
+    AM_CONDITIONAL(DX_COND_latex, false)
+    DX_ENV_APPEND(GENERATE_LATEX, NO)
+fi
+
+# Paper size for PS and/or PDF:
+AC_ARG_VAR(DOXYGEN_PAPER_SIZE,
+           [a4wide (default), a4, letter, legal or executive])
+case "$DOXYGEN_PAPER_SIZE" in
+#(
+"")
+    AC_SUBST(DOXYGEN_PAPER_SIZE, "")
+;; #(
+a4wide|a4|letter|legal|executive)
+    DX_ENV_APPEND(PAPER_SIZE, $DOXYGEN_PAPER_SIZE)
+;; #(
+*)
+    AC_MSG_ERROR([unknown DOXYGEN_PAPER_SIZE='$DOXYGEN_PAPER_SIZE'])
+;;
+esac
+
+#For debugging:
+#echo DX_FLAG_doc=$DX_FLAG_doc
+#echo DX_FLAG_dot=$DX_FLAG_dot
+#echo DX_FLAG_man=$DX_FLAG_man
+#echo DX_FLAG_html=$DX_FLAG_html
+#echo DX_FLAG_chm=$DX_FLAG_chm
+#echo DX_FLAG_chi=$DX_FLAG_chi
+#echo DX_FLAG_rtf=$DX_FLAG_rtf
+#echo DX_FLAG_xml=$DX_FLAG_xml
+#echo DX_FLAG_pdf=$DX_FLAG_pdf
+#echo DX_FLAG_ps=$DX_FLAG_ps
+#echo DX_ENV=$DX_ENV
+])

+ 186 - 0
src/recipes/lock/src/c/aminclude.am

@@ -0,0 +1,186 @@
+# Copyright (C) 2004 Oren Ben-Kiki
+# This file is distributed under the same terms as the Automake macro files.
+
+# Generate automatic documentation using Doxygen. Goals and variables values
+# are controlled by the various DX_COND_??? conditionals set by autoconf.
+#
+# The provided goals are:
+# doxygen-doc: Generate all doxygen documentation.
+# doxygen-run: Run doxygen, which will generate some of the documentation
+#              (HTML, CHM, CHI, MAN, RTF, XML) but will not do the post
+#              processing required for the rest of it (PS, PDF, and some MAN).
+# doxygen-man: Rename some doxygen generated man pages.
+# doxygen-ps: Generate doxygen PostScript documentation.
+# doxygen-pdf: Generate doxygen PDF documentation.
+#
+# Note that by default these are not integrated into the automake goals. If
+# doxygen is used to generate man pages, you can achieve this integration by
+# setting man3_MANS to the list of man pages generated and then adding the
+# dependency:
+#
+#   $(man3_MANS): doxygen-doc
+#
+# This will cause make to run doxygen and generate all the documentation.
+#
+# The following variable is intended for use in Makefile.am:
+#
+# DX_CLEANFILES = everything to clean.
+#
+# This is usually added to MOSTLYCLEANFILES.
+
+## --------------------------------- ##
+## Format-independent Doxygen rules. ##
+## --------------------------------- ##
+
+if DX_COND_doc
+
+## ------------------------------- ##
+## Rules specific for HTML output. ##
+## ------------------------------- ##
+
+if DX_COND_html
+
+DX_CLEAN_HTML = @DX_DOCDIR@/html
+
+endif DX_COND_html
+
+## ------------------------------ ##
+## Rules specific for CHM output. ##
+## ------------------------------ ##
+
+if DX_COND_chm
+
+DX_CLEAN_CHM = @DX_DOCDIR@/chm
+
+if DX_COND_chi
+
+DX_CLEAN_CHI = @DX_DOCDIR@/@PACKAGE@.chi
+
+endif DX_COND_chi
+
+endif DX_COND_chm
+
+## ------------------------------ ##
+## Rules specific for MAN output. ##
+## ------------------------------ ##
+
+if DX_COND_man
+
+DX_CLEAN_MAN = @DX_DOCDIR@/man
+
+endif DX_COND_man
+
+## ------------------------------ ##
+## Rules specific for RTF output. ##
+## ------------------------------ ##
+
+if DX_COND_rtf
+
+DX_CLEAN_RTF = @DX_DOCDIR@/rtf
+
+endif DX_COND_rtf
+
+## ------------------------------ ##
+## Rules specific for XML output. ##
+## ------------------------------ ##
+
+if DX_COND_xml
+
+DX_CLEAN_XML = @DX_DOCDIR@/xml
+
+endif DX_COND_xml
+
+## ----------------------------- ##
+## Rules specific for PS output. ##
+## ----------------------------- ##
+
+if DX_COND_ps
+
+DX_CLEAN_PS = @DX_DOCDIR@/@PACKAGE@.ps
+
+DX_PS_GOAL = doxygen-ps
+
+doxygen-ps: @DX_DOCDIR@/@PACKAGE@.ps
+
+@DX_DOCDIR@/@PACKAGE@.ps: @DX_DOCDIR@/@PACKAGE@.tag
+	cd @DX_DOCDIR@/latex; \
+	rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+	$(DX_LATEX) refman.tex; \
+	$(MAKEINDEX_PATH) refman.idx; \
+	$(DX_LATEX) refman.tex; \
+	countdown=5; \
+	while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+	                  refman.log > /dev/null 2>&1 \
+	   && test $$countdown -gt 0; do \
+	    $(DX_LATEX) refman.tex; \
+	    countdown=`expr $$countdown - 1`; \
+	done; \
+	$(DX_DVIPS) -o ../@PACKAGE@.ps refman.dvi
+
+endif DX_COND_ps
+
+## ------------------------------ ##
+## Rules specific for PDF output. ##
+## ------------------------------ ##
+
+if DX_COND_pdf
+
+DX_CLEAN_PDF = @DX_DOCDIR@/@PACKAGE@.pdf
+
+DX_PDF_GOAL = doxygen-pdf
+
+doxygen-pdf: @DX_DOCDIR@/@PACKAGE@.pdf
+
+@DX_DOCDIR@/@PACKAGE@.pdf: @DX_DOCDIR@/@PACKAGE@.tag
+	cd @DX_DOCDIR@/latex; \
+	rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+	$(DX_PDFLATEX) refman.tex; \
+	$(DX_MAKEINDEX) refman.idx; \
+	$(DX_PDFLATEX) refman.tex; \
+	countdown=5; \
+	while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+	                  refman.log > /dev/null 2>&1 \
+	   && test $$countdown -gt 0; do \
+	    $(DX_PDFLATEX) refman.tex; \
+	    countdown=`expr $$countdown - 1`; \
+	done; \
+	mv refman.pdf ../@PACKAGE@.pdf
+
+endif DX_COND_pdf
+
+## ------------------------------------------------- ##
+## Rules specific for LaTeX (shared for PS and PDF). ##
+## ------------------------------------------------- ##
+
+if DX_COND_latex
+
+DX_CLEAN_LATEX = @DX_DOCDIR@/latex
+
+endif DX_COND_latex
+
+.PHONY: doxygen-run doxygen-doc $(DX_PS_GOAL) $(DX_PDF_GOAL)
+
+.INTERMEDIATE: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+
+doxygen-run: @DX_DOCDIR@/@PACKAGE@.tag
+
+doxygen-doc: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+
+@DX_DOCDIR@/@PACKAGE@.tag: $(DX_CONFIG) $(pkginclude_HEADERS)
+	rm -rf @DX_DOCDIR@
+	$(DX_ENV) $(DX_DOXYGEN) $(srcdir)/$(DX_CONFIG)
+
+DX_CLEANFILES = \
+    @DX_DOCDIR@/@PACKAGE@.tag \
+    -r \
+    $(DX_CLEAN_HTML) \
+    $(DX_CLEAN_CHM) \
+    $(DX_CLEAN_CHI) \
+    $(DX_CLEAN_MAN) \
+    $(DX_CLEAN_RTF) \
+    $(DX_CLEAN_XML) \
+    $(DX_CLEAN_PS) \
+    $(DX_CLEAN_PDF) \
+    $(DX_CLEAN_LATEX)
+
+endif DX_COND_doc

+ 1252 - 0
src/recipes/lock/src/c/c-doc.Doxyfile

@@ -0,0 +1,1252 @@
+# Doxyfile 1.4.7
+
+# This file describes the settings to be used by the documentation system
+# doxygen (www.doxygen.org) for a project
+#
+# All text after a hash (#) is considered a comment and will be ignored
+# The format is:
+#       TAG = value [value, ...]
+# For lists items can also be appended using:
+#       TAG += value [value, ...]
+# Values that contain spaces should be placed between quotes (" ")
+
+#---------------------------------------------------------------------------
+# Project related configuration options
+#---------------------------------------------------------------------------
+
+# The PROJECT_NAME tag is a single word (or a sequence of words surrounded 
+# by quotes) that should identify the project.
+
+PROJECT_NAME = $(PROJECT)-$(VERSION)
+
+# The PROJECT_NUMBER tag can be used to enter a project or revision number. 
+# This could be handy for archiving the generated documentation or 
+# if some version control system is used.
+
+PROJECT_NUMBER = 
+
+# The OUTPUT_DIRECTORY tag is used to specify the (relative or absolute) 
+# base path where the generated documentation will be put. 
+# If a relative path is entered, it will be relative to the location 
+# where doxygen was started. If left blank the current directory will be used.
+
+OUTPUT_DIRECTORY = $(DOCDIR)
+
+# If the CREATE_SUBDIRS tag is set to YES, then doxygen will create 
+# 4096 sub-directories (in 2 levels) under the output directory of each output 
+# format and will distribute the generated files over these directories. 
+# Enabling this option can be useful when feeding doxygen a huge amount of 
+# source files, where putting all generated files in the same directory would 
+# otherwise cause performance problems for the file system.
+
+CREATE_SUBDIRS = NO
+
+# The OUTPUT_LANGUAGE tag is used to specify the language in which all 
+# documentation generated by doxygen is written. Doxygen will use this 
+# information to generate all constant output in the proper language. 
+# The default language is English, other supported languages are: 
+# Brazilian, Catalan, Chinese, Chinese-Traditional, Croatian, Czech, Danish, 
+# Dutch, Finnish, French, German, Greek, Hungarian, Italian, Japanese, 
+# Japanese-en (Japanese with English messages), Korean, Korean-en, Norwegian, 
+# Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Slovene, Spanish, 
+# Swedish, and Ukrainian.
+
+OUTPUT_LANGUAGE = English
+
+# This tag can be used to specify the encoding used in the generated output. 
+# The encoding is not always determined by the language that is chosen, 
+# but also whether or not the output is meant for Windows or non-Windows users. 
+# In case there is a difference, setting the USE_WINDOWS_ENCODING tag to YES 
+# forces the Windows encoding (this is the default for the Windows binary), 
+# whereas setting the tag to NO uses a Unix-style encoding (the default for 
+# all platforms other than Windows).
+
+USE_WINDOWS_ENCODING = NO
+
+# If the BRIEF_MEMBER_DESC tag is set to YES (the default) Doxygen will 
+# include brief member descriptions after the members that are listed in 
+# the file and class documentation (similar to JavaDoc). 
+# Set to NO to disable this.
+
+BRIEF_MEMBER_DESC = YES
+
+# If the REPEAT_BRIEF tag is set to YES (the default) Doxygen will prepend 
+# the brief description of a member or function before the detailed description. 
+# Note: if both HIDE_UNDOC_MEMBERS and BRIEF_MEMBER_DESC are set to NO, the 
+# brief descriptions will be completely suppressed.
+
+REPEAT_BRIEF = YES
+
+# This tag implements a quasi-intelligent brief description abbreviator 
+# that is used to form the text in various listings. Each string 
+# in this list, if found as the leading text of the brief description, will be 
+# stripped from the text and the result after processing the whole list, is 
+# used as the annotated text. Otherwise, the brief description is used as-is. 
+# If left blank, the following values are used ("$name" is automatically 
+# replaced with the name of the entity): "The $name class" "The $name widget" 
+# "The $name file" "is" "provides" "specifies" "contains" 
+# "represents" "a" "an" "the"
+
+ABBREVIATE_BRIEF = 
+
+# If the ALWAYS_DETAILED_SEC and REPEAT_BRIEF tags are both set to YES then 
+# Doxygen will generate a detailed section even if there is only a brief 
+# description.
+
+ALWAYS_DETAILED_SEC = NO
+
+# If the INLINE_INHERITED_MEMB tag is set to YES, doxygen will show all 
+# inherited members of a class in the documentation of that class as if those 
+# members were ordinary class members. Constructors, destructors and assignment 
+# operators of the base classes will not be shown.
+
+INLINE_INHERITED_MEMB = NO
+
+# If the FULL_PATH_NAMES tag is set to YES then Doxygen will prepend the full 
+# path before files name in the file list and in the header files. If set 
+# to NO the shortest path that makes the file name unique will be used.
+
+FULL_PATH_NAMES = YES
+
+# If the FULL_PATH_NAMES tag is set to YES then the STRIP_FROM_PATH tag 
+# can be used to strip a user-defined part of the path. Stripping is 
+# only done if one of the specified strings matches the left-hand part of 
+# the path. The tag can be used to show relative paths in the file list. 
+# If left blank the directory from which doxygen is run is used as the 
+# path to strip.
+
+STRIP_FROM_PATH = 
+
+# The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of 
+# the path mentioned in the documentation of a class, which tells 
+# the reader which header file to include in order to use a class. 
+# If left blank only the name of the header file containing the class 
+# definition is used. Otherwise one should specify the include paths that 
+# are normally passed to the compiler using the -I flag.
+
+STRIP_FROM_INC_PATH = 
+
+# If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter 
+# (but less readable) file names. This can be useful is your file systems 
+# doesn't support long names like on DOS, Mac, or CD-ROM.
+
+SHORT_NAMES = NO
+
+# If the JAVADOC_AUTOBRIEF tag is set to YES then Doxygen 
+# will interpret the first line (until the first dot) of a JavaDoc-style 
+# comment as the brief description. If set to NO, the JavaDoc 
+# comments will behave just like the Qt-style comments (thus requiring an 
+# explicit @brief command for a brief description.
+
+JAVADOC_AUTOBRIEF = NO
+
+# The MULTILINE_CPP_IS_BRIEF tag can be set to YES to make Doxygen 
+# treat a multi-line C++ special comment block (i.e. a block of //! or /// 
+# comments) as a brief description. This used to be the default behaviour. 
+# The new default is to treat a multi-line C++ comment block as a detailed 
+# description. Set this tag to YES if you prefer the old behaviour instead.
+
+MULTILINE_CPP_IS_BRIEF = NO
+
+# If the DETAILS_AT_TOP tag is set to YES then Doxygen 
+# will output the detailed description near the top, like JavaDoc.
+# If set to NO, the detailed description appears after the member 
+# documentation.
+
+DETAILS_AT_TOP = NO
+
+# If the INHERIT_DOCS tag is set to YES (the default) then an undocumented 
+# member inherits the documentation from any documented member that it 
+# re-implements.
+
+INHERIT_DOCS = YES
+
+# If the SEPARATE_MEMBER_PAGES tag is set to YES, then doxygen will produce 
+# a new page for each member. If set to NO, the documentation of a member will 
+# be part of the file/class/namespace that contains it.
+
+SEPARATE_MEMBER_PAGES = NO
+
+# The TAB_SIZE tag can be used to set the number of spaces in a tab. 
+# Doxygen uses this value to replace tabs by spaces in code fragments.
+
+TAB_SIZE = 8
+
+# This tag can be used to specify a number of aliases that acts 
+# as commands in the documentation. An alias has the form "name=value". 
+# For example adding "sideeffect=\par Side Effects:\n" will allow you to 
+# put the command \sideeffect (or @sideeffect) in the documentation, which 
+# will result in a user-defined paragraph with heading "Side Effects:". 
+# You can put \n's in the value part of an alias to insert newlines.
+
+ALIASES = 
+
+# Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C 
+# sources only. Doxygen will then generate output that is more tailored for C. 
+# For instance, some of the names that are used will be different. The list 
+# of all members will be omitted, etc.
+
+OPTIMIZE_OUTPUT_FOR_C = YES
+
+# Set the OPTIMIZE_OUTPUT_JAVA tag to YES if your project consists of Java 
+# sources only. Doxygen will then generate output that is more tailored for Java. 
+# For instance, namespaces will be presented as packages, qualified scopes 
+# will look different, etc.
+
+OPTIMIZE_OUTPUT_JAVA = NO
+
+# If you use STL classes (i.e. std::string, std::vector, etc.) but do not want to 
+# include (a tag file for) the STL sources as input, then you should 
+# set this tag to YES in order to let doxygen match functions declarations and 
+# definitions whose arguments contain STL classes (e.g. func(std::string); v.s. 
+# func(std::string) {}). This also make the inheritance and collaboration 
+# diagrams that involve STL classes more complete and accurate.
+
+BUILTIN_STL_SUPPORT = NO
+
+# If member grouping is used in the documentation and the DISTRIBUTE_GROUP_DOC 
+# tag is set to YES, then doxygen will reuse the documentation of the first 
+# member in the group (if any) for the other members of the group. By default 
+# all members of a group must be documented explicitly.
+
+DISTRIBUTE_GROUP_DOC = NO
+
+# Set the SUBGROUPING tag to YES (the default) to allow class member groups of 
+# the same type (for instance a group of public functions) to be put as a 
+# subgroup of that type (e.g. under the Public Functions section). Set it to 
+# NO to prevent subgrouping. Alternatively, this can be done per class using 
+# the \nosubgrouping command.
+
+SUBGROUPING = YES
+
+#---------------------------------------------------------------------------
+# Build related configuration options
+#---------------------------------------------------------------------------
+
+# If the EXTRACT_ALL tag is set to YES doxygen will assume all entities in 
+# documentation are documented, even if no documentation was available. 
+# Private class members and static file members will be hidden unless 
+# the EXTRACT_PRIVATE and EXTRACT_STATIC tags are set to YES
+
+EXTRACT_ALL = NO
+
+# If the EXTRACT_PRIVATE tag is set to YES all private members of a class 
+# will be included in the documentation.
+
+EXTRACT_PRIVATE = NO
+
+# If the EXTRACT_STATIC tag is set to YES all static members of a file 
+# will be included in the documentation.
+
+EXTRACT_STATIC = YES
+
+# If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs) 
+# defined locally in source files will be included in the documentation. 
+# If set to NO only classes defined in header files are included.
+
+EXTRACT_LOCAL_CLASSES = YES
+
+# This flag is only useful for Objective-C code. When set to YES local 
+# methods, which are defined in the implementation section but not in 
+# the interface are included in the documentation. 
+# If set to NO (the default) only methods in the interface are included.
+
+EXTRACT_LOCAL_METHODS = NO
+
+# If the HIDE_UNDOC_MEMBERS tag is set to YES, Doxygen will hide all 
+# undocumented members of documented classes, files or namespaces. 
+# If set to NO (the default) these members will be included in the 
+# various overviews, but no documentation section is generated. 
+# This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_MEMBERS = NO
+
+# If the HIDE_UNDOC_CLASSES tag is set to YES, Doxygen will hide all 
+# undocumented classes that are normally visible in the class hierarchy. 
+# If set to NO (the default) these classes will be included in the various 
+# overviews. This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_CLASSES = NO
+
+# If the HIDE_FRIEND_COMPOUNDS tag is set to YES, Doxygen will hide all 
+# friend (class|struct|union) declarations. 
+# If set to NO (the default) these declarations will be included in the 
+# documentation.
+
+HIDE_FRIEND_COMPOUNDS = NO
+
+# If the HIDE_IN_BODY_DOCS tag is set to YES, Doxygen will hide any 
+# documentation blocks found inside the body of a function. 
+# If set to NO (the default) these blocks will be appended to the 
+# function's detailed documentation block.
+
+HIDE_IN_BODY_DOCS = NO
+
+# The INTERNAL_DOCS tag determines if documentation 
+# that is typed after a \internal command is included. If the tag is set 
+# to NO (the default) then the documentation will be excluded. 
+# Set it to YES to include the internal documentation.
+
+INTERNAL_DOCS = NO
+
+# If the CASE_SENSE_NAMES tag is set to NO then Doxygen will only generate 
+# file names in lower-case letters. If set to YES upper-case letters are also 
+# allowed. This is useful if you have classes or files whose names only differ 
+# in case and if your file system supports case sensitive file names. Windows 
+# and Mac users are advised to set this option to NO.
+
+CASE_SENSE_NAMES = YES
+
+# If the HIDE_SCOPE_NAMES tag is set to NO (the default) then Doxygen 
+# will show members with their full class and namespace scopes in the 
+# documentation. If set to YES the scope will be hidden.
+
+HIDE_SCOPE_NAMES = NO
+
+# If the SHOW_INCLUDE_FILES tag is set to YES (the default) then Doxygen 
+# will put a list of the files that are included by a file in the documentation 
+# of that file.
+
+SHOW_INCLUDE_FILES = NO
+
+# If the INLINE_INFO tag is set to YES (the default) then a tag [inline] 
+# is inserted in the documentation for inline members.
+
+INLINE_INFO = YES
+
+# If the SORT_MEMBER_DOCS tag is set to YES (the default) then doxygen 
+# will sort the (detailed) documentation of file and class members 
+# alphabetically by member name. If set to NO the members will appear in 
+# declaration order.
+
+SORT_MEMBER_DOCS = YES
+
+# If the SORT_BRIEF_DOCS tag is set to YES then doxygen will sort the 
+# brief documentation of file, namespace and class members alphabetically 
+# by member name. If set to NO (the default) the members will appear in 
+# declaration order.
+
+SORT_BRIEF_DOCS = NO
+
+# If the SORT_BY_SCOPE_NAME tag is set to YES, the class list will be 
+# sorted by fully-qualified names, including namespaces. If set to 
+# NO (the default), the class list will be sorted only by class name, 
+# not including the namespace part. 
+# Note: This option is not very useful if HIDE_SCOPE_NAMES is set to YES.
+# Note: This option applies only to the class list, not to the 
+# alphabetical list.
+
+SORT_BY_SCOPE_NAME = NO
+
+# The GENERATE_TODOLIST tag can be used to enable (YES) or 
+# disable (NO) the todo list. This list is created by putting \todo 
+# commands in the documentation.
+
+GENERATE_TODOLIST = YES
+
+# The GENERATE_TESTLIST tag can be used to enable (YES) or 
+# disable (NO) the test list. This list is created by putting \test 
+# commands in the documentation.
+
+GENERATE_TESTLIST = YES
+
+# The GENERATE_BUGLIST tag can be used to enable (YES) or 
+# disable (NO) the bug list. This list is created by putting \bug 
+# commands in the documentation.
+
+GENERATE_BUGLIST = YES
+
+# The GENERATE_DEPRECATEDLIST tag can be used to enable (YES) or 
+# disable (NO) the deprecated list. This list is created by putting 
+# \deprecated commands in the documentation.
+
+GENERATE_DEPRECATEDLIST = YES
+
+# The ENABLED_SECTIONS tag can be used to enable conditional 
+# documentation sections, marked by \if sectionname ... \endif.
+
+ENABLED_SECTIONS = 
+
+# The MAX_INITIALIZER_LINES tag determines the maximum number of lines 
+# the initial value of a variable or define consists of for it to appear in 
+# the documentation. If the initializer consists of more lines than specified 
+# here it will be hidden. Use a value of 0 to hide initializers completely. 
+# The appearance of the initializer of individual variables and defines in the 
+# documentation can be controlled using \showinitializer or \hideinitializer 
+# command in the documentation regardless of this setting.
+
+MAX_INITIALIZER_LINES = 30
+
+# Set the SHOW_USED_FILES tag to NO to disable the list of files generated 
+# at the bottom of the documentation of classes and structs. If set to YES the 
+# list will mention the files that were used to generate the documentation.
+
+SHOW_USED_FILES = YES
+
+# If the sources in your project are distributed over multiple directories 
+# then setting the SHOW_DIRECTORIES tag to YES will show the directory hierarchy 
+# in the documentation. The default is NO.
+
+SHOW_DIRECTORIES = NO
+
+# The FILE_VERSION_FILTER tag can be used to specify a program or script that 
+# doxygen should invoke to get the current version for each file (typically from the 
+# version control system). Doxygen will invoke the program by executing (via 
+# popen()) the command <command> <input-file>, where <command> is the value of 
+# the FILE_VERSION_FILTER tag, and <input-file> is the name of an input file 
+# provided by doxygen. Whatever the program writes to standard output 
+# is used as the file version. See the manual for examples.
+
+FILE_VERSION_FILTER = 
+
+#---------------------------------------------------------------------------
+# configuration options related to warning and progress messages
+#---------------------------------------------------------------------------
+
+# The QUIET tag can be used to turn on/off the messages that are generated 
+# by doxygen. Possible values are YES and NO. If left blank NO is used.
+
+QUIET = NO
+
+# The WARNINGS tag can be used to turn on/off the warning messages that are 
+# generated by doxygen. Possible values are YES and NO. If left blank 
+# NO is used.
+
+WARNINGS = YES
+
+# If WARN_IF_UNDOCUMENTED is set to YES, then doxygen will generate warnings 
+# for undocumented members. If EXTRACT_ALL is set to YES then this flag will 
+# automatically be disabled.
+
+WARN_IF_UNDOCUMENTED = YES
+
+# If WARN_IF_DOC_ERROR is set to YES, doxygen will generate warnings for 
+# potential errors in the documentation, such as not documenting some 
+# parameters in a documented function, or documenting parameters that 
+# don't exist or using markup commands wrongly.
+
+WARN_IF_DOC_ERROR = YES
+
+# This WARN_NO_PARAMDOC option can be abled to get warnings for 
+# functions that are documented, but have no documentation for their parameters 
+# or return value. If set to NO (the default) doxygen will only warn about 
+# wrong or incomplete parameter documentation, but not about the absence of 
+# documentation.
+
+WARN_NO_PARAMDOC = NO
+
+# The WARN_FORMAT tag determines the format of the warning messages that 
+# doxygen can produce. The string should contain the $file, $line, and $text 
+# tags, which will be replaced by the file and line number from which the 
+# warning originated and the warning text. Optionally the format may contain 
+# $version, which will be replaced by the version of the file (if it could 
+# be obtained via FILE_VERSION_FILTER)
+
+WARN_FORMAT = "$file:$line: $text"
+
+# The WARN_LOGFILE tag can be used to specify a file to which warning 
+# and error messages should be written. If left blank the output is written 
+# to stderr.
+
+WARN_LOGFILE = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the input files
+#---------------------------------------------------------------------------
+
+# The INPUT tag can be used to specify the files and/or directories that contain 
+# documented source files. You may enter file names like "myfile.cpp" or 
+# directories like "/usr/src/myproject". Separate the files or directories 
+# with spaces.
+
+INPUT = include/zoo_lock.h
+
+# If the value of the INPUT tag contains directories, you can use the 
+# FILE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
+# and *.h) to filter out the source-files in the directories. If left 
+# blank the following patterns are tested: 
+# *.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.h *.hh *.hxx 
+# *.hpp *.h++ *.idl *.odl *.cs *.php *.php3 *.inc *.m *.mm *.py
+
+FILE_PATTERNS = 
+
+# The RECURSIVE tag can be used to turn specify whether or not subdirectories 
+# should be searched for input files as well. Possible values are YES and NO. 
+# If left blank NO is used.
+
+RECURSIVE = NO
+
+# The EXCLUDE tag can be used to specify files and/or directories that should 
+# excluded from the INPUT source files. This way you can easily exclude a 
+# subdirectory from a directory tree whose root is specified with the INPUT tag.
+
+EXCLUDE = 
+
+# The EXCLUDE_SYMLINKS tag can be used select whether or not files or 
+# directories that are symbolic links (a Unix filesystem feature) are excluded 
+# from the input.
+
+EXCLUDE_SYMLINKS = NO
+
+# If the value of the INPUT tag contains directories, you can use the 
+# EXCLUDE_PATTERNS tag to specify one or more wildcard patterns to exclude 
+# certain files from those directories. Note that the wildcards are matched 
+# against the file with absolute path, so to exclude all test directories 
+# for example use the pattern */test/*
+
+EXCLUDE_PATTERNS = 
+
+# The EXAMPLE_PATH tag can be used to specify one or more files or 
+# directories that contain example code fragments that are included (see 
+# the \include command).
+
+EXAMPLE_PATH = 
+
+# If the value of the EXAMPLE_PATH tag contains directories, you can use the 
+# EXAMPLE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
+# and *.h) to filter out the source-files in the directories. If left 
+# blank all files are included.
+
+EXAMPLE_PATTERNS = 
+
+# If the EXAMPLE_RECURSIVE tag is set to YES then subdirectories will be 
+# searched for input files to be used with the \include or \dontinclude 
+# commands irrespective of the value of the RECURSIVE tag. 
+# Possible values are YES and NO. If left blank NO is used.
+
+EXAMPLE_RECURSIVE = NO
+
+# The IMAGE_PATH tag can be used to specify one or more files or 
+# directories that contain image that are included in the documentation (see 
+# the \image command).
+
+IMAGE_PATH = 
+
+# The INPUT_FILTER tag can be used to specify a program that doxygen should 
+# invoke to filter for each input file. Doxygen will invoke the filter program 
+# by executing (via popen()) the command <filter> <input-file>, where <filter> 
+# is the value of the INPUT_FILTER tag, and <input-file> is the name of an 
+# input file. Doxygen will then use the output that the filter program writes 
+# to standard output.  If FILTER_PATTERNS is specified, this tag will be 
+# ignored.
+
+INPUT_FILTER = 
+
+# The FILTER_PATTERNS tag can be used to specify filters on a per file pattern 
+# basis.  Doxygen will compare the file name with each pattern and apply the 
+# filter if there is a match.  The filters are a list of the form: 
+# pattern=filter (like *.cpp=my_cpp_filter). See INPUT_FILTER for further 
+# info on how filters are used. If FILTER_PATTERNS is empty, INPUT_FILTER 
+# is applied to all files.
+
+FILTER_PATTERNS = 
+
+# If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using 
+# INPUT_FILTER) will be used to filter the input files when producing source 
+# files to browse (i.e. when SOURCE_BROWSER is set to YES).
+
+FILTER_SOURCE_FILES = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to source browsing
+#---------------------------------------------------------------------------
+
+# If the SOURCE_BROWSER tag is set to YES then a list of source files will 
+# be generated. Documented entities will be cross-referenced with these sources. 
+# Note: To get rid of all source code in the generated output, make sure also 
+# VERBATIM_HEADERS is set to NO.
+
+SOURCE_BROWSER = NO
+
+# Setting the INLINE_SOURCES tag to YES will include the body 
+# of functions and classes directly in the documentation.
+
+INLINE_SOURCES = NO
+
+# Setting the STRIP_CODE_COMMENTS tag to YES (the default) will instruct 
+# doxygen to hide any special comment blocks from generated source code 
+# fragments. Normal C and C++ comments will always remain visible.
+
+STRIP_CODE_COMMENTS = YES
+
+# If the REFERENCED_BY_RELATION tag is set to YES (the default) 
+# then for each documented function all documented 
+# functions referencing it will be listed.
+
+REFERENCED_BY_RELATION = YES
+
+# If the REFERENCES_RELATION tag is set to YES (the default) 
+# then for each documented function all documented entities 
+# called/used by that function will be listed.
+
+REFERENCES_RELATION = YES
+
+# If the REFERENCES_LINK_SOURCE tag is set to YES (the default)
+# and SOURCE_BROWSER tag is set to YES, then the hyperlinks from
+# functions in REFERENCES_RELATION and REFERENCED_BY_RELATION lists will
+# link to the source code.  Otherwise they will link to the documentstion.
+
+REFERENCES_LINK_SOURCE = YES
+
+# If the USE_HTAGS tag is set to YES then the references to source code 
+# will point to the HTML generated by the htags(1) tool instead of doxygen 
+# built-in source browser. The htags tool is part of GNU's global source 
+# tagging system (see http://www.gnu.org/software/global/global.html). You 
+# will need version 4.8.6 or higher.
+
+USE_HTAGS = NO
+
+# If the VERBATIM_HEADERS tag is set to YES (the default) then Doxygen 
+# will generate a verbatim copy of the header file for each class for 
+# which an include is specified. Set to NO to disable this.
+
+VERBATIM_HEADERS = YES
+
+#---------------------------------------------------------------------------
+# configuration options related to the alphabetical class index
+#---------------------------------------------------------------------------
+
+# If the ALPHABETICAL_INDEX tag is set to YES, an alphabetical index 
+# of all compounds will be generated. Enable this if the project 
+# contains a lot of classes, structs, unions or interfaces.
+
+ALPHABETICAL_INDEX = NO
+
+# If the alphabetical index is enabled (see ALPHABETICAL_INDEX) then 
+# the COLS_IN_ALPHA_INDEX tag can be used to specify the number of columns 
+# in which this list will be split (can be a number in the range [1..20])
+
+COLS_IN_ALPHA_INDEX = 5
+
+# In case all classes in a project start with a common prefix, all 
+# classes will be put under the same header in the alphabetical index. 
+# The IGNORE_PREFIX tag can be used to specify one or more prefixes that 
+# should be ignored while generating the index headers.
+
+IGNORE_PREFIX = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the HTML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_HTML tag is set to YES (the default) Doxygen will 
+# generate HTML output.
+
+GENERATE_HTML = $(GENERATE_HTML)
+
+# The HTML_OUTPUT tag is used to specify where the HTML docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `html' will be used as the default path.
+
+HTML_OUTPUT = html
+
+# The HTML_FILE_EXTENSION tag can be used to specify the file extension for 
+# each generated HTML page (for example: .htm,.php,.asp). If it is left blank 
+# doxygen will generate files with .html extension.
+
+HTML_FILE_EXTENSION = .html
+
+# The HTML_HEADER tag can be used to specify a personal HTML header for 
+# each generated HTML page. If it is left blank doxygen will generate a 
+# standard header.
+
+HTML_HEADER = 
+
+# The HTML_FOOTER tag can be used to specify a personal HTML footer for 
+# each generated HTML page. If it is left blank doxygen will generate a 
+# standard footer.
+
+HTML_FOOTER = 
+
+# The HTML_STYLESHEET tag can be used to specify a user-defined cascading 
+# style sheet that is used by each HTML page. It can be used to 
+# fine-tune the look of the HTML output. If the tag is left blank doxygen 
+# will generate a default style sheet. Note that doxygen will try to copy 
+# the style sheet file to the HTML output directory, so don't put your own 
+# stylesheet in the HTML output directory as well, or it will be erased!
+
+HTML_STYLESHEET = 
+
+# If the HTML_ALIGN_MEMBERS tag is set to YES, the members of classes, 
+# files or namespaces will be aligned in HTML using tables. If set to 
+# NO a bullet list will be used.
+
+HTML_ALIGN_MEMBERS = YES
+
+# If the GENERATE_HTMLHELP tag is set to YES, additional index files 
+# will be generated that can be used as input for tools like the 
+# Microsoft HTML help workshop to generate a compressed HTML help file (.chm) 
+# of the generated HTML documentation.
+
+GENERATE_HTMLHELP = $(GENERATE_HTMLHELP)
+
+# If the GENERATE_HTMLHELP tag is set to YES, the CHM_FILE tag can 
+# be used to specify the file name of the resulting .chm file. You 
+# can add a path in front of the file if the result should not be 
+# written to the html output directory.
+
+CHM_FILE = ../$(PROJECT).chm
+
+# If the GENERATE_HTMLHELP tag is set to YES, the HHC_LOCATION tag can 
+# be used to specify the location (absolute path including file name) of 
+# the HTML help compiler (hhc.exe). If non-empty doxygen will try to run 
+# the HTML help compiler on the generated index.hhp.
+
+HHC_LOCATION = $(HHC_PATH)
+
+# If the GENERATE_HTMLHELP tag is set to YES, the GENERATE_CHI flag 
+# controls if a separate .chi index file is generated (YES) or that 
+# it should be included in the master .chm file (NO).
+
+GENERATE_CHI = $(GENERATE_CHI)
+
+# If the GENERATE_HTMLHELP tag is set to YES, the BINARY_TOC flag 
+# controls whether a binary table of contents is generated (YES) or a 
+# normal table of contents (NO) in the .chm file.
+
+BINARY_TOC = NO
+
+# The TOC_EXPAND flag can be set to YES to add extra items for group members 
+# to the contents of the HTML help documentation and to the tree view.
+
+TOC_EXPAND = NO
+
+# The DISABLE_INDEX tag can be used to turn on/off the condensed index at 
+# top of each HTML page. The value NO (the default) enables the index and 
+# the value YES disables it.
+
+DISABLE_INDEX = NO
+
+# This tag can be used to set the number of enum values (range [1..20]) 
+# that doxygen will group on one line in the generated HTML documentation.
+
+ENUM_VALUES_PER_LINE = 4
+
+# If the GENERATE_TREEVIEW tag is set to YES, a side panel will be
+# generated containing a tree-like index structure (just like the one that 
+# is generated for HTML Help). For this to work a browser that supports 
+# JavaScript, DHTML, CSS and frames is required (for instance Mozilla 1.0+, 
+# Netscape 6.0+, Internet explorer 5.0+, or Konqueror). Windows users are 
+# probably better off using the HTML help feature.
+
+GENERATE_TREEVIEW = NO
+
+# If the treeview is enabled (see GENERATE_TREEVIEW) then this tag can be 
+# used to set the initial width (in pixels) of the frame in which the tree 
+# is shown.
+
+TREEVIEW_WIDTH = 250
+
+#---------------------------------------------------------------------------
+# configuration options related to the LaTeX output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_LATEX tag is set to YES (the default) Doxygen will 
+# generate Latex output.
+
+GENERATE_LATEX = $(GENERATE_LATEX)
+
+# The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `latex' will be used as the default path.
+
+LATEX_OUTPUT = latex
+
+# The LATEX_CMD_NAME tag can be used to specify the LaTeX command name to be 
+# invoked. If left blank `latex' will be used as the default command name.
+
+LATEX_CMD_NAME = latex
+
+# The MAKEINDEX_CMD_NAME tag can be used to specify the command name to 
+# generate index for LaTeX. If left blank `makeindex' will be used as the 
+# default command name.
+
+MAKEINDEX_CMD_NAME = makeindex
+
+# If the COMPACT_LATEX tag is set to YES Doxygen generates more compact 
+# LaTeX documents. This may be useful for small projects and may help to 
+# save some trees in general.
+
+COMPACT_LATEX = NO
+
+# The PAPER_TYPE tag can be used to set the paper type that is used 
+# by the printer. Possible values are: a4, a4wide, letter, legal and 
+# executive. If left blank a4wide will be used.
+
+PAPER_TYPE = $(PAPER_SIZE)
+
+# The EXTRA_PACKAGES tag can be to specify one or more names of LaTeX 
+# packages that should be included in the LaTeX output.
+
+EXTRA_PACKAGES = 
+
+# The LATEX_HEADER tag can be used to specify a personal LaTeX header for 
+# the generated latex document. The header should contain everything until 
+# the first chapter. If it is left blank doxygen will generate a 
+# standard header. Notice: only use this tag if you know what you are doing!
+
+LATEX_HEADER = 
+
+# If the PDF_HYPERLINKS tag is set to YES, the LaTeX that is generated 
+# is prepared for conversion to pdf (using ps2pdf). The pdf file will 
+# contain links (just like the HTML output) instead of page references 
+# This makes the output suitable for online browsing using a pdf viewer.
+
+PDF_HYPERLINKS = NO
+
+# If the USE_PDFLATEX tag is set to YES, pdflatex will be used instead of 
+# plain latex in the generated Makefile. Set this option to YES to get a 
+# higher quality PDF documentation.
+
+USE_PDFLATEX = $(GENERATE_PDF)
+
+# If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \\batchmode. 
+# command to the generated LaTeX files. This will instruct LaTeX to keep 
+# running if errors occur, instead of asking the user for help. 
+# This option is also used when generating formulas in HTML.
+
+LATEX_BATCHMODE = NO
+
+# If LATEX_HIDE_INDICES is set to YES then doxygen will not 
+# include the index chapters (such as File Index, Compound Index, etc.) 
+# in the output.
+
+LATEX_HIDE_INDICES = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the RTF output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_RTF tag is set to YES Doxygen will generate RTF output 
+# The RTF output is optimized for Word 97 and may not look very pretty with 
+# other RTF readers or editors.
+
+GENERATE_RTF = $(GENERATE_RTF)
+
+# The RTF_OUTPUT tag is used to specify where the RTF docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `rtf' will be used as the default path.
+
+RTF_OUTPUT = rtf
+
+# If the COMPACT_RTF tag is set to YES Doxygen generates more compact 
+# RTF documents. This may be useful for small projects and may help to 
+# save some trees in general.
+
+COMPACT_RTF = NO
+
+# If the RTF_HYPERLINKS tag is set to YES, the RTF that is generated 
+# will contain hyperlink fields. The RTF file will 
+# contain links (just like the HTML output) instead of page references. 
+# This makes the output suitable for online browsing using WORD or other 
+# programs which support those fields. 
+# Note: wordpad (write) and others do not support links.
+
+RTF_HYPERLINKS = NO
+
+# Load stylesheet definitions from file. Syntax is similar to doxygen's 
+# config file, i.e. a series of assignments. You only have to provide 
+# replacements, missing definitions are set to their default value.
+
+RTF_STYLESHEET_FILE = 
+
+# Set optional variables used in the generation of an rtf document. 
+# Syntax is similar to doxygen's config file.
+
+RTF_EXTENSIONS_FILE = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the man page output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_MAN tag is set to YES (the default) Doxygen will 
+# generate man pages
+
+GENERATE_MAN = $(GENERATE_MAN)
+
+# The MAN_OUTPUT tag is used to specify where the man pages will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `man' will be used as the default path.
+
+MAN_OUTPUT = man
+
+# The MAN_EXTENSION tag determines the extension that is added to 
+# the generated man pages (default is the subroutine's section .3)
+
+MAN_EXTENSION = .3
+
+# If the MAN_LINKS tag is set to YES and Doxygen generates man output, 
+# then it will generate one additional man file for each entity 
+# documented in the real man page(s). These additional files 
+# only source the real man page, but without them the man command 
+# would be unable to find the correct page. The default is NO.
+
+MAN_LINKS = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the XML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_XML tag is set to YES Doxygen will 
+# generate an XML file that captures the structure of 
+# the code including all documentation.
+
+GENERATE_XML = $(GENERATE_XML)
+
+# The XML_OUTPUT tag is used to specify where the XML pages will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `xml' will be used as the default path.
+
+XML_OUTPUT = xml
+
+# The XML_SCHEMA tag can be used to specify an XML schema, 
+# which can be used by a validating XML parser to check the 
+# syntax of the XML files.
+
+XML_SCHEMA = 
+
+# The XML_DTD tag can be used to specify an XML DTD, 
+# which can be used by a validating XML parser to check the 
+# syntax of the XML files.
+
+XML_DTD = 
+
+# If the XML_PROGRAMLISTING tag is set to YES Doxygen will 
+# dump the program listings (including syntax highlighting 
+# and cross-referencing information) to the XML output. Note that 
+# enabling this will significantly increase the size of the XML output.
+
+XML_PROGRAMLISTING = YES
+
+#---------------------------------------------------------------------------
+# configuration options for the AutoGen Definitions output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_AUTOGEN_DEF tag is set to YES Doxygen will 
+# generate an AutoGen Definitions (see autogen.sf.net) file 
+# that captures the structure of the code including all 
+# documentation. Note that this feature is still experimental 
+# and incomplete at the moment.
+
+GENERATE_AUTOGEN_DEF = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the Perl module output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_PERLMOD tag is set to YES Doxygen will 
+# generate a Perl module file that captures the structure of 
+# the code including all documentation. Note that this 
+# feature is still experimental and incomplete at the 
+# moment.
+
+GENERATE_PERLMOD = NO
+
+# If the PERLMOD_LATEX tag is set to YES Doxygen will generate 
+# the necessary Makefile rules, Perl scripts and LaTeX code to be able 
+# to generate PDF and DVI output from the Perl module output.
+
+PERLMOD_LATEX = NO
+
+# If the PERLMOD_PRETTY tag is set to YES the Perl module output will be 
+# nicely formatted so it can be parsed by a human reader.  This is useful 
+# if you want to understand what is going on.  On the other hand, if this 
+# tag is set to NO the size of the Perl module output will be much smaller 
+# and Perl will parse it just the same.
+
+PERLMOD_PRETTY = YES
+
+# The names of the make variables in the generated doxyrules.make file 
+# are prefixed with the string contained in PERLMOD_MAKEVAR_PREFIX. 
+# This is useful so different doxyrules.make files included by the same 
+# Makefile don't overwrite each other's variables.
+
+PERLMOD_MAKEVAR_PREFIX = 
+
+#---------------------------------------------------------------------------
+# Configuration options related to the preprocessor   
+#---------------------------------------------------------------------------
+
+# If the ENABLE_PREPROCESSING tag is set to YES (the default) Doxygen will 
+# evaluate all C-preprocessor directives found in the sources and include 
+# files.
+
+ENABLE_PREPROCESSING = YES
+
+# If the MACRO_EXPANSION tag is set to YES Doxygen will expand all macro 
+# names in the source code. If set to NO (the default) only conditional 
+# compilation will be performed. Macro expansion can be done in a controlled 
+# way by setting EXPAND_ONLY_PREDEF to YES.
+
+MACRO_EXPANSION = NO
+
+# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES 
+# then the macro expansion is limited to the macros specified with the 
+# PREDEFINED and EXPAND_AS_DEFINED tags.
+
+EXPAND_ONLY_PREDEF = NO
+
+# If the SEARCH_INCLUDES tag is set to YES (the default) the includes files 
+# in the INCLUDE_PATH (see below) will be search if a #include is found.
+
+SEARCH_INCLUDES = YES
+
+# The INCLUDE_PATH tag can be used to specify one or more directories that 
+# contain include files that are not input files but should be processed by 
+# the preprocessor.
+
+INCLUDE_PATH = 
+
+# You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard 
+# patterns (like *.h and *.hpp) to filter out the header-files in the 
+# directories. If left blank, the patterns specified with FILE_PATTERNS will 
+# be used.
+
+INCLUDE_FILE_PATTERNS = 
+
+# The PREDEFINED tag can be used to specify one or more macro names that 
+# are defined before the preprocessor is started (similar to the -D option of 
+# gcc). The argument of the tag is a list of macros of the form: name 
+# or name=definition (no spaces). If the definition and the = are 
+# omitted =1 is assumed. To prevent a macro definition from being 
+# undefined via #undef or recursively expanded use the := operator 
+# instead of the = operator.
+
+PREDEFINED = 
+
+# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then 
+# this tag can be used to specify a list of macro names that should be expanded. 
+# The macro definition that is found in the sources will be used. 
+# Use the PREDEFINED tag if you want to use a different macro definition.
+
+EXPAND_AS_DEFINED = 
+
+# If the SKIP_FUNCTION_MACROS tag is set to YES (the default) then 
+# doxygen's preprocessor will remove all function-like macros that are alone 
+# on a line, have an all uppercase name, and do not end with a semicolon. Such 
+# function macros are typically used for boiler-plate code, and will confuse 
+# the parser if not removed.
+
+SKIP_FUNCTION_MACROS = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to external references   
+#---------------------------------------------------------------------------
+
+# The TAGFILES option can be used to specify one or more tagfiles. 
+# Optionally an initial location of the external documentation 
+# can be added for each tagfile. The format of a tag file without 
+# this location is as follows: 
+#   TAGFILES = file1 file2 ... 
+# Adding location for the tag files is done as follows: 
+#   TAGFILES = file1=loc1 "file2 = loc2" ... 
+# where "loc1" and "loc2" can be relative or absolute paths or 
+# URLs. If a location is present for each tag, the installdox tool 
+# does not have to be run to correct the links.
+# Note that each tag file must have a unique name
+# (where the name does NOT include the path)
+# If a tag file is not located in the directory in which doxygen 
+# is run, you must also specify the path to the tagfile here.
+
+TAGFILES = 
+
+# When a file name is specified after GENERATE_TAGFILE, doxygen will create 
+# a tag file that is based on the input files it reads.
+
+GENERATE_TAGFILE = $(DOCDIR)/$(PROJECT).tag
+
+# If the ALLEXTERNALS tag is set to YES all external classes will be listed 
+# in the class index. If set to NO only the inherited external classes 
+# will be listed.
+
+ALLEXTERNALS = NO
+
+# If the EXTERNAL_GROUPS tag is set to YES all external groups will be listed 
+# in the modules index. If set to NO, only the current project's groups will 
+# be listed.
+
+EXTERNAL_GROUPS = YES
+
+# The PERL_PATH should be the absolute path and name of the perl script 
+# interpreter (i.e. the result of `which perl').
+
+PERL_PATH = /usr/bin/perl
+
+#---------------------------------------------------------------------------
+# Configuration options related to the dot tool   
+#---------------------------------------------------------------------------
+
+# If the CLASS_DIAGRAMS tag is set to YES (the default) Doxygen will 
+# generate a inheritance diagram (in HTML, RTF and LaTeX) for classes with base 
+# or super classes. Setting the tag to NO turns the diagrams off. Note that 
+# this option is superseded by the HAVE_DOT option below. This is only a 
+# fallback. It is recommended to install and use dot, since it yields more 
+# powerful graphs.
+
+CLASS_DIAGRAMS = YES
+
+# If set to YES, the inheritance and collaboration graphs will hide 
+# inheritance and usage relations if the target is undocumented 
+# or is not a class.
+
+HIDE_UNDOC_RELATIONS = YES
+
+# If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is 
+# available from the path. This tool is part of Graphviz, a graph visualization 
+# toolkit from AT&T and Lucent Bell Labs. The other options in this section 
+# have no effect if this option is set to NO (the default)
+
+HAVE_DOT = $(HAVE_DOT)
+
+# If the CLASS_GRAPH and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for each documented class showing the direct and 
+# indirect inheritance relations. Setting this tag to YES will force the 
+# the CLASS_DIAGRAMS tag to NO.
+
+CLASS_GRAPH = YES
+
+# If the COLLABORATION_GRAPH and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for each documented class showing the direct and 
+# indirect implementation dependencies (inheritance, containment, and 
+# class references variables) of the class with other documented classes.
+
+COLLABORATION_GRAPH = YES
+
+# If the GROUP_GRAPHS and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for groups, showing the direct groups dependencies
+
+GROUP_GRAPHS = YES
+
+# If the UML_LOOK tag is set to YES doxygen will generate inheritance and 
+# collaboration diagrams in a style similar to the OMG's Unified Modeling 
+# Language.
+
+UML_LOOK = NO
+
+# If set to YES, the inheritance and collaboration graphs will show the 
+# relations between templates and their instances.
+
+TEMPLATE_RELATIONS = NO
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDE_GRAPH, and HAVE_DOT 
+# tags are set to YES then doxygen will generate a graph for each documented 
+# file showing the direct and indirect include dependencies of the file with 
+# other documented files.
+
+INCLUDE_GRAPH = YES
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDED_BY_GRAPH, and 
+# HAVE_DOT tags are set to YES then doxygen will generate a graph for each 
+# documented header file showing the documented files that directly or 
+# indirectly include this file.
+
+INCLUDED_BY_GRAPH = YES
+
+# If the CALL_GRAPH and HAVE_DOT tags are set to YES then doxygen will 
+# generate a call dependency graph for every global function or class method. 
+# Note that enabling this option will significantly increase the time of a run. 
+# So in most cases it will be better to enable call graphs for selected 
+# functions only using the \callgraph command.
+
+CALL_GRAPH = NO
+
+# If the CALLER_GRAPH and HAVE_DOT tags are set to YES then doxygen will 
+# generate a caller dependency graph for every global function or class method. 
+# Note that enabling this option will significantly increase the time of a run. 
+# So in most cases it will be better to enable caller graphs for selected 
+# functions only using the \callergraph command.
+
+CALLER_GRAPH = NO
+
+# If the GRAPHICAL_HIERARCHY and HAVE_DOT tags are set to YES then doxygen 
+# will graphical hierarchy of all classes instead of a textual one.
+
+GRAPHICAL_HIERARCHY = YES
+
+# If the DIRECTORY_GRAPH, SHOW_DIRECTORIES and HAVE_DOT tags are set to YES 
+# then doxygen will show the dependencies a directory has on other directories 
+# in a graphical way. The dependency relations are determined by the #include
+# relations between the files in the directories.
+
+DIRECTORY_GRAPH = YES
+
+# The DOT_IMAGE_FORMAT tag can be used to set the image format of the images 
+# generated by dot. Possible values are png, jpg, or gif
+# If left blank png will be used.
+
+DOT_IMAGE_FORMAT = png
+
+# The tag DOT_PATH can be used to specify the path where the dot tool can be 
+# found. If left blank, it is assumed the dot tool can be found in the path.
+
+DOT_PATH = $(DOT_PATH)
+
+# The DOTFILE_DIRS tag can be used to specify one or more directories that 
+# contain dot files that are included in the documentation (see the 
+# \dotfile command).
+
+DOTFILE_DIRS = 
+
+# The MAX_DOT_GRAPH_WIDTH tag can be used to set the maximum allowed width 
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than 
+# this value, doxygen will try to truncate the graph, so that it fits within 
+# the specified constraint. Beware that most browsers cannot cope with very 
+# large images.
+
+MAX_DOT_GRAPH_WIDTH = 1024
+
+# The MAX_DOT_GRAPH_HEIGHT tag can be used to set the maximum allows height 
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than 
+# this value, doxygen will try to truncate the graph, so that it fits within 
+# the specified constraint. Beware that most browsers cannot cope with very 
+# large images.
+
+MAX_DOT_GRAPH_HEIGHT = 1024
+
+# The MAX_DOT_GRAPH_DEPTH tag can be used to set the maximum depth of the 
+# graphs generated by dot. A depth value of 3 means that only nodes reachable 
+# from the root by following a path via at most 3 edges will be shown. Nodes 
+# that lay further from the root node will be omitted. Note that setting this 
+# option to 1 or 2 may greatly reduce the computation time needed for large 
+# code bases. Also note that a graph may be further truncated if the graph's 
+# image dimensions are not sufficient to fit the graph (see MAX_DOT_GRAPH_WIDTH 
+# and MAX_DOT_GRAPH_HEIGHT). If 0 is used for the depth value (the default), 
+# the graph is not depth-constrained.
+
+MAX_DOT_GRAPH_DEPTH = 0
+
+# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent 
+# background. This is disabled by default, which results in a white background. 
+# Warning: Depending on the platform used, enabling this option may lead to 
+# badly anti-aliased labels on the edges of a graph (i.e. they become hard to 
+# read).
+
+DOT_TRANSPARENT = NO
+
+# Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output 
+# files in one run (i.e. multiple -o and -T options on the command line). This 
+# makes dot run faster, but since only newer versions of dot (>1.8.10) 
+# support this, this feature is disabled by default.
+
+DOT_MULTI_TARGETS = NO
+
+# If the GENERATE_LEGEND tag is set to YES (the default) Doxygen will 
+# generate a legend page explaining the meaning of the various boxes and 
+# arrows in the dot generated graphs.
+
+GENERATE_LEGEND = YES
+
+# If the DOT_CLEANUP tag is set to YES (the default) Doxygen will 
+# remove the intermediate dot files that are used to generate 
+# the various graphs.
+
+DOT_CLEANUP = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to the search engine   
+#---------------------------------------------------------------------------
+
+# The SEARCHENGINE tag specifies whether or not a search engine should be 
+# used. If set to NO the values of all tags below this one will be ignored.
+
+SEARCHENGINE = NO

+ 82 - 0
src/recipes/lock/src/c/configure.ac

@@ -0,0 +1,82 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#                                               -*- Autoconf -*-
+# Process this file with autoconf to produce a configure script.
+
+AC_PREREQ(2.59)
+
+AC_INIT([zoolock], [3.2.0])
+
+AC_CONFIG_SRCDIR([include/zoo_lock.h])
+
+PACKAGE=zoolock
+VERSION=1.0
+
+AC_SUBST(PACKAGE)
+AC_SUBST(VERSION)
+
+BUILD_PATH="`pwd`"
+
+# Checks for programs.
+AC_LANG_CPLUSPLUS
+
+AM_INIT_AUTOMAKE([-Wall foreign])
+# Checks for libraries.
+
+#initialize Doxygen support
+DX_HTML_FEATURE(ON)
+DX_CHM_FEATURE(OFF)
+DX_CHI_FEATURE(OFF)
+DX_MAN_FEATURE(OFF)
+DX_RTF_FEATURE(OFF)
+DX_XML_FEATURE(OFF)
+DX_PDF_FEATURE(OFF)
+DX_PS_FEATURE(OFF)
+DX_INIT_DOXYGEN([zookeeper-locks],[c-doc.Doxyfile],[docs])
+
+  
+ZOOKEEPER_PATH=${BUILD_PATH}/../../../../../src/c
+ZOOKEEPER_LD=-L${BUILD_PATH}/../../../../../src/c\ -lzookeeper_mt
+
+AC_SUBST(ZOOKEEPER_PATH)
+AC_SUBST(ZOOKEEPER_LD)
+
+# Checks for header files.
+AC_HEADER_DIRENT
+AC_HEADER_STDC
+AC_CHECK_HEADERS([fcntl.h stdlib.h string.h sys/time.h unistd.h])
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_HEADER_STDBOOL
+AC_C_CONST
+AC_TYPE_UID_T
+AC_C_INLINE
+AC_TYPE_OFF_T
+AC_TYPE_SIZE_T
+AC_STRUCT_ST_BLOCKS
+AC_HEADER_TIME
+AC_C_VOLATILE
+AC_PROG_CC
+AC_PROG_LIBTOOL
+#check for cppunit 
+AM_PATH_CPPUNIT(1.10.2)
+# Checks for library functions.
+AC_FUNC_UTIME_NULL
+AC_CHECK_FUNCS([gettimeofday memset mkdir rmdir strdup strerror strstr strtol strtoul strtoull utime])
+
+AC_CONFIG_FILES([Makefile])
+AC_OUTPUT
+AC_C_VOLATILE

+ 168 - 0
src/recipes/lock/src/c/include/zoo_lock.h

@@ -0,0 +1,168 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef ZOOKEEPER_LOCK_H_
+#define ZOOKEEPER_LOCK_H_
+
+#include <zookeeper.h>
+#include <pthread.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+/**
+ * \brief the call back function called on status change of lock
+ * 
+ * the call back funtion is called with a rc of 0 if lock is acquired and 
+ * with an rc of 1 if the lock is released
+ * \param rc the value to let us know if its locked or unlocked
+ * \param cbdata the callback data that we passed when initializing 
+ * the zookeeper lock.
+ */
+
+typedef void (* zkr_lock_completion) (int rc, void* cbdata);
+
+/** 
+ * \file zoo_lock.h
+ * \brief zookeeper recipe for locking and leader election.
+ * this api implements a writelock on a given path in zookeeper.
+ * this api can also be used for leader election.
+ */
+
+struct zkr_lock_mutex {
+    zhandle_t *zh;
+    char *path;
+    struct ACL_vector *acl;
+    char *id;
+    void *cbdata;
+    zkr_lock_completion completion;
+    pthread_mutex_t pmutex;
+    int isOwner;
+    char* ownerid;
+};
+
+typedef struct zkr_lock_mutex zkr_lock_mutex_t;
+
+
+/**
+ * \brief initializing a zookeeper lock.
+ *
+ * this method instantiates the zookeeper mutex lock.
+ * \param mutex the mutex to initialize
+ * \param zh the zookeeper handle to use
+ * \param path the path in zookeeper to use for locking
+ * \param acl the acls to use in zookeeper.
+ * \return return 0 if successful.
+ */
+ZOOAPI int zkr_lock_init(zkr_lock_mutex_t *mutex, zhandle_t* zh, 
+                      char* path, struct ACL_vector *acl);
+
+/**
+ * \brief initializing a zookeeper lock.
+ *
+ *
+ * this method instantiates the zookeeper mutex lock with
+ * a completion function.
+ * 
+ * \param mutex the mutex to initialize
+ * \param zh the zookeeper handle to use
+ * \param path the path in zookeeper to use for locking
+ * \param acl the acls to use in zookeeper.
+ * \param completion the callback thats called when lock 
+ * is acquired and released.
+ * \param cbdata the callback method is called with data
+ * \return return 0 if successful.
+ */
+ZOOAPI int zkr_lock_init_cb(zkr_lock_mutex_t *mutex, zhandle_t* zh,
+                      char* path, struct ACL_vector *acl, 
+                      zkr_lock_completion completion, void* cbdata);
+
+/**
+ * \brief lock the zookeeper mutex
+ *
+ * this method tries locking the mutex
+ * \param mutex the zookeeper mutex
+ * \return return 0 if there is no error. check 
+ * with zkr_lock_isowner() if you have the lock
+ */
+ZOOAPI int zkr_lock_lock(zkr_lock_mutex_t *mutex);
+
+/**
+ * \brief unlock the zookeeper mutex
+ *
+ * this method unlocks the zookeeper mutex
+ * \param mutex the zookeeper mutex
+ * \return return 0 if there is not error in executing unlock.
+ * else returns non zero
+ */
+ZOOAPI int zkr_lock_unlock(zkr_lock_mutex_t *mutex);
+
+/**
+ * \brief set the callback function for zookeeper mutex
+ * 
+ * this method sets the callback for zookeeper mutex
+ * \param mutex the zookeeper mutex
+ * \param callback the call back completion function
+ */
+ZOOAPI void zkr_lock_setcallback(zkr_lock_mutex_t *mutex, 
+                           zkr_lock_completion completion);
+
+/**
+ * \brief get the callback function for zookeeper mutex
+ *
+ * this method gets the callback funtion for zookeeper mutex
+ * \param mutex the zookeeper mutex
+ * \return the lock completion function
+ */
+ZOOAPI zkr_lock_completion zkr_lock_getcallback(zkr_lock_mutex_t *mutex);
+
+/**
+ * \brief destroy the mutex 
+ * this method free the mutex
+ * \param mutex destroy the zookepeer lock.
+ * \return return 0 if destroyed.
+ */
+ZOOAPI int zkr_lock_destroy(zkr_lock_mutex_t* mutex);
+
+/**
+ * \brief return the parent path this mutex is using
+ * this method returns the parent path
+ * \param mutex the mutex
+ * \return return the parent path
+ */
+ZOOAPI char* zkr_lock_getpath(zkr_lock_mutex_t *mutex);
+
+/**
+ * \brief return if this mutex is owner of the lock
+ * this method returns if its owner or not
+ * \param mutex the mutex
+ * \return return true if is owner and false if not
+ */
+ZOOAPI int zkr_lock_isowner(zkr_lock_mutex_t *mutex);
+
+/**
+ * \brief return the id for this mutex
+ * this mutex retunrns the id string 
+ * \param mutex the mutex
+ * \return the id for this mutex
+ */
+ZOOAPI char* zkr_lock_getid(zkr_lock_mutex_t *mutex);
+
+#ifdef __cplusplus
+}
+#endif
+#endif  //ZOOKEEPER_LOCK_H_

+ 396 - 0
src/recipes/lock/src/c/src/zoo_lock.c

@@ -0,0 +1,396 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifdef DLL_EXPORT
+#define USE_STATIC_LIB
+#endif
+
+#if defined(__CYGWIN__)
+#define USE_IPV6
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <zookeeper_log.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <limits.h>
+#include <zoo_lock.h>
+#include <stdbool.h>
+#ifdef HAVE_SYS_UTSNAME_H
+#include <sys/utsname.h>
+#endif
+
+#ifdef HAVE_GETPWUID_R
+#include <pwd.h>
+#endif
+
+#define IF_DEBUG(x) if (logLevel==ZOO_LOG_LEVEL_DEBUG) {x;}
+
+ 
+ZOOAPI int zkr_lock_init(zkr_lock_mutex_t* mutex, zhandle_t* zh,
+                      char* path, struct ACL_vector *acl) {
+    mutex->zh = zh;
+    mutex->path = path;
+    mutex->acl = acl;
+    mutex->completion = NULL;
+    mutex->cbdata = NULL;
+    mutex->id = NULL;
+    mutex->ownerid = NULL;
+    mutex->isOwner = 0;
+    pthread_mutex_init(&(mutex->pmutex), NULL);
+    return 0;
+}
+
+ZOOAPI int zkr_lock_init_cb(zkr_lock_mutex_t *mutex, zhandle_t* zh,
+                         char *path, struct ACL_vector *acl,
+                         zkr_lock_completion completion, void* cbdata) {
+    mutex->zh = zh;
+    mutex->path = path;
+    mutex->acl = acl;
+    mutex->completion = completion;
+    mutex->cbdata = cbdata;
+    mutex->isOwner = 0;
+    mutex->ownerid = NULL;
+    mutex->id = NULL;
+    pthread_mutex_init(&(mutex->pmutex), NULL);
+    return 0;
+}
+
+/**
+ * unlock the mutex
+ */
+ZOOAPI int zkr_lock_unlock(zkr_lock_mutex_t *mutex) {
+    pthread_mutex_lock(&(mutex->pmutex));
+    zhandle_t *zh = mutex->zh;
+    if (mutex->id != NULL) {
+        int len = strlen(mutex->path) + strlen(mutex->id) + 2;
+        char buf[len];
+        sprintf(buf, "%s/%s", mutex->path, mutex->id);
+        int ret = 0;
+        int count = 0;
+        struct timespec ts;
+        ts.tv_sec = 0;
+        ts.tv_nsec = (.5)*1000000;
+        ret = ZCONNECTIONLOSS;
+        while (ret == ZCONNECTIONLOSS && (count < 3)) {
+            ret = zoo_delete(zh, buf, -1);
+            if (ret == ZCONNECTIONLOSS) {
+                LOG_DEBUG(("connectionloss while deleting the node"));
+                nanosleep(&ts, 0);
+                count++;
+            }
+        }
+        if (ret == ZOK || ret == ZNONODE) {
+            zkr_lock_completion completion = mutex->completion;
+            if (completion != NULL) {
+                completion(1, mutex->cbdata);
+            }
+
+            free(mutex->id);
+            mutex->id = NULL;
+            pthread_mutex_unlock(&(mutex->pmutex));
+            return 0;
+        }
+        LOG_WARN(("not able to connect to server - giving up"));
+        pthread_mutex_unlock(&(mutex->pmutex));
+        return ZCONNECTIONLOSS;
+    }
+    pthread_mutex_unlock(&(mutex->pmutex));
+    return ZSYSTEMERROR;
+}
+
+static void free_String_vector(struct String_vector *v) {
+    if (v->data) {
+        int32_t i;
+        for (i=0; i<v->count; i++) {
+            free(v->data[i]);
+        }
+        free(v->data);
+        v->data = 0;
+    }
+}
+
+static int vstrcmp(const void* str1, const void* str2) {
+    const char **a = (const char**)str1;
+    const char **b = (const char**) str2;
+    return strcmp(strrchr(*a, '-')+1, strrchr(*b, '-')+1); 
+} 
+
+static void sort_children(struct String_vector *vector) {
+    qsort( vector->data, vector->count, sizeof(char*), &vstrcmp);
+}
+        
+static char* child_floor(char **sorted_data, int len, char *element) {
+    char* ret = NULL;
+    int i =0;
+    for (i=0; i < len; i++) {
+        if (strcmp(sorted_data[i], element) < 0) {
+            ret = sorted_data[i];
+        }
+    }
+    return ret;
+}
+
+static void lock_watcher_fn(zhandle_t* zh, int type, int state,
+                            const char* path, void *watcherCtx) {
+    //callback that we registered 
+    //should be called
+    zkr_lock_lock((zkr_lock_mutex_t*) watcherCtx);
+}
+
+/**
+ * get the last name of the path
+ */
+static char* getName(char* str) {
+    char* name = strrchr(str, '/');
+    if (name == NULL) 
+        return NULL;
+    return strdup(name + 1);
+}
+
+/**
+ * just a method to retry get children
+ */
+static int retry_getchildren(zhandle_t *zh, char* path, struct String_vector *vector, 
+                             struct timespec *ts, int retry) {
+    int ret = ZCONNECTIONLOSS;
+    int count = 0;
+    while (ret == ZCONNECTIONLOSS && count < retry) {
+        ret = zoo_get_children(zh, path, 0, vector);
+        if (ret == ZCONNECTIONLOSS) {
+            LOG_DEBUG(("connection loss to the server"));
+            nanosleep(ts, 0);
+            count++;
+        }
+    }
+    return ret;
+}
+
+/** see if our node already exists
+ * if it does then we dup the name and 
+ * return it
+ */
+static char* lookupnode(struct String_vector *vector, char *prefix) {
+    char *ret = NULL;
+    if (vector->data) {
+        int i = 0;
+        for (i = 0; i < vector->count; i++) {
+            char* child = vector->data[i];
+            if (strncmp(prefix, child, strlen(prefix)) == 0) {
+                ret = strdup(child);
+                break;
+            }
+        }
+    }
+    return ret;
+}
+
+/** retry zoo_wexists
+ */
+static int retry_zoowexists(zhandle_t *zh, char* path, watcher_fn watcher, void* ctx,
+                            struct Stat *stat, struct timespec *ts, int retry) {
+    int ret = ZCONNECTIONLOSS;
+    int count = 0;
+    while (ret == ZCONNECTIONLOSS && count < retry) {
+        ret = zoo_wexists(zh, path, watcher, ctx, stat);
+        if (ret == ZCONNECTIONLOSS) {
+            LOG_DEBUG(("connectionloss while setting watch on my predecessor"));
+            nanosleep(ts, 0);
+            count++;
+        }
+    }
+    return ret;
+}
+                        
+/**
+ * the main code that does the zookeeper leader 
+ * election. this code creates its own ephemeral 
+ * node on the given path and sees if its the first
+ * one on the list and claims to be a leader if and only
+ * if its the first one of children in the paretn path
+ */
+static int zkr_lock_operation(zkr_lock_mutex_t *mutex, struct timespec *ts) {
+    zhandle_t *zh = mutex->zh;
+    char *path = mutex->path;
+    char *id = mutex->id;
+    struct Stat stat;
+    char* owner_id = NULL;
+    int retry = 3;
+    do {
+        const clientid_t *cid = zoo_client_id(zh);
+        // get the session id
+        int64_t session = cid->client_id;
+        char prefix[30];
+        int ret = 0;
+#if defined(__x86_64__)
+        snprintf(prefix, 30, "x-%016lx-", session);
+#else 
+        snprintf(prefix, 30, "x-%016llx-", session);
+#endif
+        struct String_vector vectorst;
+        vectorst.data = NULL;
+        vectorst.count = 0;
+        ret = ZCONNECTIONLOSS;
+        ret = retry_getchildren(zh, path, &vectorst, ts, retry);
+        if (ret != ZOK)
+            return ret;
+        struct String_vector *vector = &vectorst;
+        mutex->id = lookupnode(vector, prefix);
+        free_String_vector(vector);
+        if (mutex->id == NULL) {
+            int len = strlen(path) + strlen(prefix) + 2;
+            char buf[len];
+            char retbuf[len+20];
+            snprintf(buf, len, "%s/%s", path, prefix);
+            ret = ZCONNECTIONLOSS;
+            ret = zoo_create(zh, buf, NULL, 0,  mutex->acl, 
+                             ZOO_EPHEMERAL|ZOO_SEQUENCE, retbuf, (len+20));
+            
+            // do not want to retry the create since 
+            // we would end up creating more than one child
+            if (ret != ZOK) {
+                LOG_WARN(("could not create zoo node %s", buf));
+                return ret;
+            }
+            mutex->id = getName(retbuf);
+        }
+        
+        if (mutex->id != NULL) {
+            ret = ZCONNECTIONLOSS;
+            ret = retry_getchildren(zh, path, vector, ts, retry);
+            if (ret != ZOK) {
+                LOG_WARN(("could not connect to server"));
+                return ret;
+            }
+            //sort this list
+            sort_children(vector);
+            owner_id = vector->data[0];
+            mutex->ownerid = strdup(owner_id);
+            id = mutex->id;
+            char* lessthanme = child_floor(vector->data, vector->count, id);
+            if (lessthanme != NULL) {
+                int flen = strlen(mutex->path) + strlen(lessthanme) + 2;
+                char last_child[flen];
+                sprintf(last_child, "%s/%s",mutex->path, lessthanme);
+                ret = ZCONNECTIONLOSS;
+                ret = retry_zoowexists(zh, last_child, &lock_watcher_fn, mutex, 
+                                       &stat, ts, retry);
+                // cannot watch my predecessor i am giving up
+                // we need to be able to watch the predecessor 
+                // since if we do not become a leader the others 
+                // will keep waiting
+                if (ret != ZOK) {
+                    free_String_vector(vector);
+                    LOG_WARN(("unable to watch my predecessor"));
+                    ret = zkr_lock_unlock(mutex);
+                    while (ret == 0) {
+                        //we have to give up our leadership
+                        // since we cannot watch out predecessor
+                        ret = zkr_lock_unlock(mutex);
+                    }
+                    return ret;
+                }
+                // we are not the owner of the lock
+                mutex->isOwner = 0;
+            }
+            else {
+                // this is the case when we are the owner 
+                // of the lock
+                if (strcmp(mutex->id, owner_id) == 0) {
+                    LOG_DEBUG(("got the zoo lock owner - %s", mutex->id));
+                    mutex->isOwner = 1;
+                    if (mutex->completion != NULL) {
+                        mutex->completion(0, mutex->cbdata);
+                    }
+                    return ZOK;
+                }
+            }
+            free_String_vector(vector);
+            return ZOK;
+        }
+    } while (mutex->id == NULL);
+    return ZOK;
+}
+
+ZOOAPI int zkr_lock_lock(zkr_lock_mutex_t *mutex) {
+    pthread_mutex_lock(&(mutex->pmutex));
+    zhandle_t *zh = mutex->zh;
+    char *path = mutex->path;
+    struct Stat stat;
+    int exists = zoo_exists(zh, path, 0, &stat);
+    int count = 0;
+    struct timespec ts;
+    ts.tv_sec = 0;
+    ts.tv_nsec = (.5)*1000000;
+    // retry to see if the path exists and 
+    // and create if the path does not exist
+    while ((exists == ZCONNECTIONLOSS || exists == ZNONODE) && (count <4)) {
+        count++;
+        // retry the operation
+        if (exists == ZCONNECTIONLOSS) 
+            exists = zoo_exists(zh, path, 0, &stat);
+        else if (exists == ZNONODE) 
+            exists = zoo_create(zh, path, NULL, 0, mutex->acl, 0, NULL, 0);
+        nanosleep(&ts, 0);
+          
+    }
+
+    // need to check if we cannot still access the server 
+    int check_retry = ZCONNECTIONLOSS;
+    count = 0;
+    while (check_retry != ZOK && count <4) {
+        check_retry = zkr_lock_operation(mutex, &ts);
+        if (check_retry != ZOK) {
+            nanosleep(&ts, 0);
+            count++;
+        }
+    }
+    pthread_mutex_unlock(&(mutex->pmutex));
+    return zkr_lock_isowner(mutex);
+}
+
+                    
+ZOOAPI char* zkr_lock_getpath(zkr_lock_mutex_t *mutex) {
+    return mutex->path;
+}
+
+ZOOAPI int zkr_lock_isowner(zkr_lock_mutex_t *mutex) {
+    return (mutex->id != NULL && mutex->ownerid != NULL 
+            && (strcmp(mutex->id, mutex->ownerid) == 0));
+}
+
+ZOOAPI char* zkr_lock_getid(zkr_lock_mutex_t *mutex) {
+    return mutex->ownerid;
+}
+
+ZOOAPI int zkr_lock_destroy(zkr_lock_mutex_t* mutex) {
+    if (mutex->id) 
+        free(mutex->id);
+    mutex->path = NULL;
+    mutex->acl = NULL;
+    mutex->completion = NULL;
+    pthread_mutex_destroy(&(mutex->pmutex));
+    mutex->isOwner = 0;
+    if (mutex->ownerid) 
+        free(mutex->ownerid);
+    return 0;
+}
+

+ 201 - 0
src/recipes/lock/src/c/tests/TestClient.cc

@@ -0,0 +1,201 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <cppunit/extensions/HelperMacros.h>
+
+#include <stdlib.h>
+#include <sys/select.h>
+#include <cppunit/TestAssert.h>
+
+
+using namespace std;
+
+#include <cstring>
+#include <list>
+
+#include <zookeeper.h>
+#include <zoo_lock.h>
+
+static void yield(zhandle_t *zh, int i)
+{
+    sleep(i);
+}
+
+typedef struct evt {
+    string path;
+    int type;
+} evt_t;
+
+typedef struct watchCtx {
+private:
+    list<evt_t> events;
+public:
+    bool connected;
+    zhandle_t *zh;
+    
+    watchCtx() {
+        connected = false;
+        zh = 0;
+    }
+    ~watchCtx() {
+        if (zh) {
+            zookeeper_close(zh);
+            zh = 0;
+        }
+    }
+
+    evt_t getEvent() {
+        evt_t evt;
+        evt = events.front();
+        events.pop_front();
+        return evt;
+    }
+
+    int countEvents() {
+        int count;
+        count = events.size();
+        return count;
+    }
+
+    void putEvent(evt_t evt) {
+        events.push_back(evt);
+    }
+
+    bool waitForConnected(zhandle_t *zh) {
+        time_t expires = time(0) + 10;
+        while(!connected && time(0) < expires) {
+            yield(zh, 1);
+        }
+        return connected;
+    }
+    bool waitForDisconnected(zhandle_t *zh) {
+        time_t expires = time(0) + 15;
+        while(connected && time(0) < expires) {
+            yield(zh, 1);
+        }
+        return !connected;
+    }
+} watchctx_t; 
+
+class Zookeeper_locktest : public CPPUNIT_NS::TestFixture
+{
+    CPPUNIT_TEST_SUITE(Zookeeper_locktest);
+    CPPUNIT_TEST(testlock);
+    CPPUNIT_TEST_SUITE_END();
+
+    static void watcher(zhandle_t *, int type, int state, const char *path,void*v){
+        watchctx_t *ctx = (watchctx_t*)v;
+
+        if (state == ZOO_CONNECTED_STATE) {
+            ctx->connected = true;
+        } else {
+            ctx->connected = false;
+        }
+        if (type != ZOO_SESSION_EVENT) {
+            evt_t evt;
+            evt.path = path;
+            evt.type = type;
+            ctx->putEvent(evt);
+        }
+    }
+
+    static const char hostPorts[];
+
+    const char *getHostPorts() {
+        return hostPorts;
+    }
+
+    zhandle_t *createClient(watchctx_t *ctx) {
+        zhandle_t *zk = zookeeper_init(hostPorts, watcher, 10000, 0,
+                                       ctx, 0);
+        ctx->zh = zk;
+        sleep(1);
+        return zk;
+    }
+    
+public:
+
+#define ZKSERVER_CMD "./tests/zkServer.sh"
+
+    void setUp()
+    {
+        char cmd[1024];
+        sprintf(cmd, "%s startClean %s", ZKSERVER_CMD, getHostPorts());
+        CPPUNIT_ASSERT(system(cmd) == 0);
+    }
+    
+
+    void startServer() {
+        char cmd[1024];
+        sprintf(cmd, "%s start %s", ZKSERVER_CMD, getHostPorts());
+        CPPUNIT_ASSERT(system(cmd) == 0);
+    }
+
+    void stopServer() {
+        tearDown();
+    }
+
+    void tearDown()
+    {
+        char cmd[1024];
+        sprintf(cmd, "%s stop %s", ZKSERVER_CMD, getHostPorts());
+        CPPUNIT_ASSERT(system(cmd) == 0);
+    }
+    
+
+    void testlock()
+    {
+        watchctx_t ctx;
+        int rc;
+        struct Stat stat;
+        char buf[1024];
+        int blen;
+        struct String_vector strings;
+        const char *testName;
+        zkr_lock_mutex_t mutexes[3];
+        int count = 3;
+        int i = 0;
+        char* path = "/test-lock";
+        for (i=0; i< 3; i++) {
+            zhandle_t *zh = createClient(&ctx);
+            zkr_lock_init(&mutexes[i], zh, path, &ZOO_OPEN_ACL_UNSAFE);
+            zkr_lock_lock(&mutexes[i]);
+        }
+        sleep(30);
+        zkr_lock_mutex leader = mutexes[0];
+        zkr_lock_mutex mutex;
+        int ret = strcmp(leader.id, leader.ownerid);
+        CPPUNIT_ASSERT(ret == 0);
+        for(i=1; i < count; i++) {
+            mutex = mutexes[i];
+            CPPUNIT_ASSERT(strcmp(mutex.id, mutex.ownerid) != 0);
+        } 
+        zkr_lock_unlock(&leader);
+        sleep(30);
+        zkr_lock_mutex secondleader = mutexes[1];
+        CPPUNIT_ASSERT(strcmp(secondleader.id , secondleader.ownerid) == 0);
+        for (i=2; i<count; i++) {
+            mutex = mutexes[i];
+            CPPUNIT_ASSERT(strcmp(mutex.id, mutex.ownerid) != 0);
+        }
+    }
+
+};
+
+const char Zookeeper_locktest::hostPorts[] = "127.0.0.1:22181";
+CPPUNIT_TEST_SUITE_REGISTRATION(Zookeeper_locktest);

+ 114 - 0
src/recipes/lock/src/c/tests/TestDriver.cc

@@ -0,0 +1,114 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string>
+#include <cppunit/TestRunner.h>
+#include <cppunit/CompilerOutputter.h>
+#include <cppunit/TestResult.h>
+#include <cppunit/TestResultCollector.h>
+#include <cppunit/TextTestProgressListener.h>
+#include <cppunit/BriefTestProgressListener.h>
+#include <cppunit/extensions/TestFactoryRegistry.h>
+#include <stdexcept>
+#include <cppunit/Exception.h>
+#include <cppunit/TestFailure.h>
+#include <cppunit/XmlOutputter.h>
+#include <fstream>
+
+#include "Util.h"
+
+using namespace std;
+
+CPPUNIT_NS_BEGIN
+
+class EclipseOutputter: public CompilerOutputter
+{
+public:
+  EclipseOutputter(TestResultCollector *result,ostream &stream):
+        CompilerOutputter(result,stream,"%p:%l: "),stream_(stream)
+    {
+    }
+    virtual void printFailedTestName( TestFailure *failure ){}
+    virtual void printFailureMessage( TestFailure *failure )
+    {
+      stream_<<": ";
+      Message msg = failure->thrownException()->message();
+      stream_<< msg.shortDescription();
+
+      string text;
+      for(int i=0; i<msg.detailCount();i++){
+          text+=msg.detailAt(i);
+          if(i+1!=msg.detailCount())
+              text+=", ";
+      }
+      if(text.length()!=0)
+          stream_ <<" ["<<text<<"]";
+      stream_<<"\n";
+    }
+    ostream& stream_;
+};
+
+CPPUNIT_NS_END
+
+int main( int argc, char* argv[] ) { 
+   // if command line contains "-ide" then this is the post build check
+   // => the output must be in the compiler error format.
+   //bool selfTest = (argc > 1) && (std::string("-ide") == argv[1]);
+   globalTestConfig.addConfigFromCmdLine(argc,argv);
+
+   // Create the event manager and test controller
+   CPPUNIT_NS::TestResult controller;
+   // Add a listener that colllects test result
+   CPPUNIT_NS::TestResultCollector result;
+   controller.addListener( &result );
+   
+   // Add a listener that print dots as tests run.
+   // CPPUNIT_NS::TextTestProgressListener progress;
+   CPPUNIT_NS::BriefTestProgressListener progress;
+   controller.addListener( &progress );
+ 
+   CPPUNIT_NS::TestRunner runner;
+   runner.addTest( CPPUNIT_NS::TestFactoryRegistry::getRegistry().makeTest() );
+ 
+   try
+   {
+     cout << "Running "  <<  globalTestConfig.getTestName();
+     runner.run( controller, globalTestConfig.getTestName());
+     cout<<endl;
+
+     // Print test in a compiler compatible format.
+     CPPUNIT_NS::EclipseOutputter outputter( &result,cout);
+     outputter.write(); 
+
+ // Uncomment this for XML output
+#ifdef ENABLE_XML_OUTPUT
+     std::ofstream file( "tests.xml" );
+     CPPUNIT_NS::XmlOutputter xml( &result, file );
+     xml.setStyleSheet( "report.xsl" );
+     xml.write();
+     file.close();
+#endif
+   }
+   catch ( std::invalid_argument &e )  // Test path not resolved
+   {
+     cout<<"\nERROR: "<<e.what()<<endl;
+     return 0;
+   }
+
+   return result.wasSuccessful() ? 0 : 1;
+ }

+ 30 - 0
src/recipes/lock/src/c/tests/Util.cc

@@ -0,0 +1,30 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Util.h"
+
+const std::string EMPTY_STRING;
+
+TestConfig globalTestConfig;
+
+void millisleep(int ms){
+    timespec ts;
+    ts.tv_sec=ms/1000;
+    ts.tv_nsec=(ms%1000)*1000000; // to nanoseconds
+    nanosleep(&ts,0);
+}

+ 134 - 0
src/recipes/lock/src/c/tests/Util.h

@@ -0,0 +1,134 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef UTIL_H_
+#define UTIL_H_
+
+#include <map>
+#include <vector>
+#include <string>
+
+// number of elements in array
+#define COUNTOF(array) sizeof(array)/sizeof(array[0])
+
+#define DECLARE_WRAPPER(ret,sym,sig) \
+    extern "C" ret __real_##sym sig; \
+    extern "C" ret __wrap_##sym sig
+
+#define CALL_REAL(sym,params) \
+    __real_##sym params
+
+// must include "src/zookeeper_log.h" to be able to use this macro
+#define TEST_TRACE(x) \
+    log_message(3,__LINE__,__func__,format_log_message x)
+
+extern const std::string EMPTY_STRING;
+
+// *****************************************************************************
+// A bit of wizardry to get to the bare type from a reference or a pointer 
+// to the type
+template <class T>
+struct TypeOp {
+    typedef T BareT;
+    typedef T ArgT;
+};
+
+// partial specialization for reference types
+template <class T>
+struct TypeOp<T&>{
+    typedef T& ArgT;
+    typedef typename TypeOp<T>::BareT BareT;
+};
+
+// partial specialization for pointers
+template <class T>
+struct TypeOp<T*>{
+    typedef T* ArgT;
+    typedef typename TypeOp<T>::BareT BareT;
+};
+
+// *****************************************************************************
+// Container utilities
+
+template <class K, class V>
+void putValue(std::map<K,V>& map,const K& k, const V& v){
+    typedef std::map<K,V> Map;
+    typename Map::const_iterator it=map.find(k);
+    if(it==map.end())
+        map.insert(typename Map::value_type(k,v));
+    else
+        map[k]=v;
+}
+
+template <class K, class V>
+bool getValue(const std::map<K,V>& map,const K& k,V& v){
+    typedef std::map<K,V> Map;
+    typename Map::const_iterator it=map.find(k);
+    if(it==map.end())
+        return false;
+    v=it->second;
+    return true;
+}
+
+// *****************************************************************************
+// misc utils
+
+// millisecond sleep
+void millisleep(int ms);
+// evaluate given predicate until it returns true or the timeout 
+// (in millis) has expired
+template<class Predicate>
+int ensureCondition(const Predicate& p,int timeout){
+    int elapsed=0;
+    while(!p() && elapsed<timeout){
+        millisleep(2);
+        elapsed+=2;
+    }
+    return elapsed;
+};
+
+// *****************************************************************************
+// test global configuration data 
+class TestConfig{
+    typedef std::vector<std::string> CmdLineOptList;
+public:
+    typedef CmdLineOptList::const_iterator const_iterator;
+    TestConfig(){}
+    ~TestConfig(){}
+    void addConfigFromCmdLine(int argc, char* argv[]){
+        if(argc>=2)
+            testName_=argv[1];
+        for(int i=2; i<argc;++i)
+            cmdOpts_.push_back(argv[i]);
+    }
+    const_iterator getExtraOptBegin() const {return cmdOpts_.begin();}
+    const_iterator getExtraOptEnd() const {return cmdOpts_.end();}
+    size_t getExtraOptCount() const {
+        return cmdOpts_.size();
+    }
+    const std::string& getTestName() const {
+        return testName_=="all"?EMPTY_STRING:testName_;
+    }
+private:
+    CmdLineOptList cmdOpts_;
+    std::string testName_;
+};
+
+extern TestConfig globalTestConfig;
+
+#endif /*UTIL_H_*/

+ 47 - 0
src/recipes/lock/src/c/tests/zkServer.sh

@@ -0,0 +1,47 @@
+#!/bin/bash
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+if [ "x$1" == "x" ]
+then
+	echo "USAGE: $0 startClean|start|stop hostPorts"
+	exit 2
+fi
+
+if [ "x$1" == "xstartClean" ]
+then
+	rm -rf /tmp/zkdata
+fi
+
+# Make sure nothing is left over from before
+fuser -skn tcp 22181/tcp
+
+case $1 in
+start|startClean)
+	mkdir -p /tmp/zkdata
+	java -cp ../../../../../zookeeper-dev.jar:../../../../../src/java/lib/log4j-1.2.15.jar:../../../../../conf/ org.apache.zookeeper.server.ZooKeeperServerMain 22181 /tmp/zkdata &> /tmp/zk.log &
+	sleep 5
+	;;
+stop)
+	# Already killed above
+	;;
+*)
+	echo "Unknown command " + $1
+	exit 2
+esac
+

+ 38 - 0
src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/LockListener.java

@@ -0,0 +1,38 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+/**
+ * This class has two methods which are call
+ * back methods when a lock is acquired and 
+ * when the lock is released.
+ *
+ */
+public interface LockListener {
+    /**
+     * call back called when the lock 
+     * is acquired
+     */
+    public void lockAcquired();
+    
+    /**
+     * call back called when the lock is 
+     * released.
+     */
+    public void lockReleased();
+}

+ 192 - 0
src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ProtocolSupport.java

@@ -0,0 +1,192 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import org.apache.log4j.Logger;
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.ZooDefs;
+import org.apache.zookeeper.ZooKeeper;
+import org.apache.zookeeper.data.ACL;
+import org.apache.zookeeper.data.Stat;
+import org.apache.zookeeper.recipes.lock.ZooKeeperOperation;
+
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * A base class for protocol implementations which provides a number of higher 
+ * level helper methods for working with ZooKeeper along with retrying synchronous
+ *  operations if the connection to ZooKeeper closes such as 
+ *  {@link #retryOperation(ZooKeeperOperation)}
+ *
+ */
+class ProtocolSupport {
+    private static final Logger LOG = Logger.getLogger(ProtocolSupport.class);
+
+    protected final ZooKeeper zookeeper;
+    private AtomicBoolean closed = new AtomicBoolean(false);
+    private long retryDelay = 500L;
+    private int retryCount = 10;
+    private List<ACL> acl = ZooDefs.Ids.OPEN_ACL_UNSAFE;
+
+    public ProtocolSupport(ZooKeeper zookeeper) {
+        this.zookeeper = zookeeper;
+    }
+
+    /**
+     * Closes this strategy and releases any ZooKeeper resources; but keeps the
+     *  ZooKeeper instance open
+     */
+    public void close() {
+        if (closed.compareAndSet(false, true)) {
+            doClose();
+        }
+    }
+    
+    /**
+     * return zookeeper client instance
+     * @return zookeeper client instance
+     */
+    public ZooKeeper getZookeeper() {
+        return zookeeper;
+    }
+
+    /**
+     * return the acl its using
+     * @return the acl.
+     */
+    public List<ACL> getAcl() {
+        return acl;
+    }
+
+    /**
+     * set the acl 
+     * @param acl the acl to set to
+     */
+    public void setAcl(List<ACL> acl) {
+        this.acl = acl;
+    }
+
+    /**
+     * get the retry delay in milliseconds
+     * @return the retry delay
+     */
+    public long getRetryDelay() {
+        return retryDelay;
+    }
+
+    /**
+     * Sets the time waited between retry delays
+     * @param retryDelay the retry delay
+     */
+    public void setRetryDelay(long retryDelay) {
+        this.retryDelay = retryDelay;
+    }
+
+    /**
+     * Allow derived classes to perform 
+     * some custom closing operations to release resources
+     */
+    protected void doClose() {
+    }
+
+
+    /**
+     * Perform the given operation, retrying if the connection fails
+     * @return object. it needs to be cast to the callee's expected 
+     * return type.
+     */
+    protected Object retryOperation(ZooKeeperOperation operation) 
+        throws KeeperException, InterruptedException {
+        KeeperException exception = null;
+        for (int i = 0; i < retryCount; i++) {
+            try {
+                return operation.execute();
+            } catch (KeeperException.SessionExpiredException e) {
+                LOG.warn("Session expired for: " + zookeeper + " so reconnecting due to: " + e, e);
+                throw e;
+            } catch (KeeperException.ConnectionLossException e) {
+                if (exception == null) {
+                    exception = e;
+                }
+                LOG.debug("Attempt " + i + " failed with connection loss so " +
+                		"attempting to reconnect: " + e, e);
+                retryDelay(i);
+            }
+        }
+        throw exception;
+    }
+
+    /**
+     * Ensures that the given path exists with no data, the current
+     * ACL and no flags
+     * @param path
+     */
+    protected void ensurePathExists(String path) {
+        ensureExists(path, null, acl, CreateMode.PERSISTENT);
+    }
+
+    /**
+     * Ensures that the given path exists with the given data, ACL and flags
+     * @param path
+     * @param acl
+     * @param flags
+     */
+    protected void ensureExists(final String path, final byte[] data,
+            final List<ACL> acl, final CreateMode flags) {
+        try {
+            retryOperation(new ZooKeeperOperation() {
+                public boolean execute() throws KeeperException, InterruptedException {
+                    Stat stat = zookeeper.exists(path, false);
+                    if (stat != null) {
+                        return true;
+                    }
+                    zookeeper.create(path, data, acl, flags);
+                    return true;
+                }
+            });
+        } catch (KeeperException e) {
+            LOG.warn("Caught: " + e, e);
+        } catch (InterruptedException e) {
+            LOG.warn("Caught: " + e, e);
+        }
+    }
+
+    /**
+     * Returns true if this protocol has been closed
+     * @return true if this protocol is closed
+     */
+    protected boolean isClosed() {
+        return closed.get();
+    }
+
+    /**
+     * Performs a retry delay if this is not the first attempt
+     * @param attemptCount the number of the attempts performed so far
+     */
+    protected void retryDelay(int attemptCount) {
+        if (attemptCount > 0) {
+            try {
+                Thread.sleep(attemptCount * retryDelay);
+            } catch (InterruptedException e) {
+                LOG.debug("Failed to sleep: " + e, e);
+            }
+        }
+    }
+}

+ 295 - 0
src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/WriteLock.java

@@ -0,0 +1,295 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import org.apache.log4j.Logger;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.WatchedEvent;
+import org.apache.zookeeper.Watcher;
+import static org.apache.zookeeper.CreateMode.EPHEMERAL_SEQUENTIAL;
+import org.apache.zookeeper.ZooKeeper;
+import org.apache.zookeeper.data.ACL;
+import org.apache.zookeeper.data.Stat;
+
+import java.util.List;
+import java.util.SortedSet;
+import java.util.TreeSet;
+
+/**
+ * A <a href="package.html">protocol to implement an exclusive
+ *  write lock or to elect a leader</a>. <p/> You invoke {@link #lock()} to 
+ *  start the process of grabbing the lock; you may get the lock then or it may be 
+ *  some time later. <p/> You can register a listener so that you are invoked 
+ *  when you get the lock; otherwise you can ask if you have the lock
+ *  by calling {@link #isOwner()}
+ *
+ */
+public class WriteLock extends ProtocolSupport {
+    private static final Logger LOG = Logger.getLogger(WriteLock.class);
+
+    private final String dir;
+    private String id;
+    private ZNodeName idName;
+    private String ownerId;
+    private String lastChildId;
+    private byte[] data = {0x12, 0x34};
+    private LockListener callback;
+    private LockZooKeeperOperation zop;
+    
+    /**
+     * zookeeper contructor for writelock
+     * @param zookeeper zookeeper client instance
+     * @param dir the parent path you want to use for locking
+     * @param acls the acls that you want to use for all the paths, 
+     * if null world read/write is used.
+     */
+    public WriteLock(ZooKeeper zookeeper, String dir, List<ACL> acl) {
+        super(zookeeper);
+        this.dir = dir;
+        if (acl != null) {
+            setAcl(acl);
+        }
+        this.zop = new LockZooKeeperOperation();
+    }
+    
+    /**
+     * zookeeper contructor for writelock with callback
+     * @param zookeeper the zookeeper client instance
+     * @param dir the parent path you want to use for locking
+     * @param acl the acls that you want to use for all the paths
+     * @param callback the call back instance
+     */
+    public WriteLock(ZooKeeper zookeeper, String dir, List<ACL> acl, 
+            LockListener callback) {
+        this(zookeeper, dir, acl);
+        this.callback = callback;
+    }
+
+    /**
+     * return the current locklistener
+     * @return the locklistener
+     */
+    public LockListener getLockListener() {
+        return this.callback;
+    }
+    
+    /**
+     * register a different call back listener
+     * @param callback the call back instance
+     */
+    public void setLockListener(LockListener callback) {
+        this.callback = callback;
+    }
+
+    /**
+     * Removes the lock or associated znode if 
+     * you no longer require the lock. this also 
+     * removes your request in the queue for locking
+     * in case you do not already hold the lock.
+     * @throws RuntimeException throws a runtime exception
+     * if it cannot connect to zookeeper.
+     */
+    public synchronized void unlock() throws RuntimeException {
+        
+        if (!isClosed() && id != null) {
+            // we don't need to retry this operation in the case of failure
+            // as ZK will remove ephemeral files and we don't wanna hang
+            // this process when closing if we cannot reconnect to ZK
+            try {
+                
+                ZooKeeperOperation zopdel = new ZooKeeperOperation() {
+                    public boolean execute() throws KeeperException,
+                        InterruptedException {
+                        zookeeper.delete(id, -1);   
+                        return Boolean.TRUE;
+                    }
+                };
+                zopdel.execute();
+            } catch (InterruptedException e) {
+                LOG.warn("Caught: " + e, e);
+                //set that we have been interrupted.
+               Thread.currentThread().interrupt();
+            } catch (KeeperException.NoNodeException e) {
+                // do nothing
+            } catch (KeeperException e) {
+                LOG.warn("Caught: " + e, e);
+                throw (RuntimeException) new RuntimeException(e.getMessage()).
+                    initCause(e);
+            }
+            finally {
+                if (callback != null) {
+                    callback.lockReleased();
+                }
+                id = null;
+            }
+        }
+    }
+    
+    /** 
+     * the watcher called on  
+     * getting watch while watching 
+     * my predecessor
+     */
+    private class LockWatcher implements Watcher {
+        public void process(WatchedEvent event) {
+            // lets either become the leader or watch the new/updated node
+            LOG.debug("Watcher fired on path: " + event.getPath() + " state: " + 
+                    event.getState() + " type " + event.getType());
+            try {
+                lock();
+            } catch (Exception e) {
+                LOG.warn("Failed to acquire lock: " + e, e);
+            }
+        }
+    }
+    
+    /**
+     * a zoookeeper operation that is mainly responsible
+     * for all the magic required for locking.
+     */
+    private  class LockZooKeeperOperation implements ZooKeeperOperation {
+        
+        /** find if we have been created earler if not create our node
+         * 
+         * @param prefix the prefix node
+         * @param zookeeper teh zookeeper client
+         * @param dir the dir paretn
+         * @throws KeeperException
+         * @throws InterruptedException
+         */
+        private void findPrefixInChildren(String prefix, ZooKeeper zookeeper, String dir) 
+            throws KeeperException, InterruptedException {
+            List<String> names = zookeeper.getChildren(dir, false);
+            for (String name : names) {
+                if (name.startsWith(prefix)) {
+                    id = name;
+                    if (LOG.isDebugEnabled()) {
+                        LOG.debug("Found id created last time: " + id);
+                    }
+                    break;
+                }
+            }
+            if (id == null) {
+                id = zookeeper.create(dir + "/" + prefix, data, 
+                        getAcl(), EPHEMERAL_SEQUENTIAL);
+
+                if (LOG.isDebugEnabled()) {
+                    LOG.debug("Created id: " + id);
+                }
+            }
+
+        }
+        
+        /**
+         * the command that is run and retried for actually 
+         * obtaining the lock
+         * @return if the command was successful or not
+         */
+        public boolean execute() throws KeeperException, InterruptedException {
+            do {
+                if (id == null) {
+                    long sessionId = zookeeper.getSessionId();
+                    String prefix = "x-" + sessionId + "-";
+                    // lets try look up the current ID if we failed 
+                    // in the middle of creating the znode
+                    findPrefixInChildren(prefix, zookeeper, dir);
+                    idName = new ZNodeName(id);
+                }
+                if (id != null) {
+                    List<String> names = zookeeper.getChildren(dir, false);
+                    if (names.isEmpty()) {
+                        LOG.warn("No children in: " + dir + " when we've just " +
+                        "created one! Lets recreate it...");
+                        // lets force the recreation of the id
+                        id = null;
+                    } else {
+                        // lets sort them explicitly (though they do seem to come back in order ususally :)
+                        SortedSet<ZNodeName> sortedNames = new TreeSet<ZNodeName>();
+                        for (String name : names) {
+                            sortedNames.add(new ZNodeName(dir + "/" + name));
+                        }
+                        ownerId = sortedNames.first().getName();
+                        SortedSet<ZNodeName> lessThanMe = sortedNames.headSet(idName);
+                        if (!lessThanMe.isEmpty()) {
+                            ZNodeName lastChildName = lessThanMe.last();
+                            lastChildId = lastChildName.getName();
+                            if (LOG.isDebugEnabled()) {
+                                LOG.debug("watching less than me node: " + lastChildId);
+                            }
+                            Stat stat = zookeeper.exists(lastChildId, new LockWatcher());
+                            if (stat != null) {
+                                return Boolean.FALSE;
+                            } else {
+                                LOG.warn("Could not find the" +
+                                		" stats for less than me: " + lastChildName.getName());
+                            }
+                        } else {
+                            if (isOwner()) {
+                                if (callback != null) {
+                                    callback.lockAcquired();
+                                }
+                                return Boolean.TRUE;
+                            }
+                        }
+                    }
+                }
+            }
+            while (id == null);
+            return Boolean.FALSE;
+        }
+    };
+
+    /**
+     * Attempts to acquire the exclusive write lock returning whether or not it was
+     * acquired. Note that the exclusive lock may be acquired some time later after
+     * this method has been invoked due to the current lock owner going away.
+     */
+    public synchronized boolean lock() throws KeeperException, InterruptedException {
+        if (isClosed()) {
+            return false;
+        }
+        ensurePathExists(dir);
+
+        return (Boolean) retryOperation(zop);
+    }
+
+    /**
+     * return the parent dir for lock
+     * @return the parent dir used for locks.
+     */
+    public String getDir() {
+        return dir;
+    }
+
+    /**
+     * Returns true if this node is the owner of the
+     *  lock (or the leader)
+     */
+    public boolean isOwner() {
+        return id != null && ownerId != null && id.equals(ownerId);
+    }
+
+    /**
+     * return the id for this lock
+     * @return the id for this lock
+     */
+    public String getId() {
+       return this.id;
+    }
+}
+

+ 109 - 0
src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ZNodeName.java

@@ -0,0 +1,109 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import org.apache.log4j.Logger;
+
+/**
+ * Represents an ephemeral znode name which has an ordered sequence number
+ * and can be sorted in order
+ *
+ */
+class ZNodeName implements Comparable<ZNodeName> {
+    private final String name;
+    private String prefix;
+    private int sequence = -1;
+    private static final Logger LOG = Logger.getLogger(ZNodeName.class);
+    
+    public ZNodeName(String name) {
+        if (name == null) {
+            throw new NullPointerException("id cannot be null");
+        }
+        this.name = name;
+        this.prefix = name;
+        int idx = name.lastIndexOf('-');
+        if (idx >= 0) {
+            this.prefix = name.substring(0, idx);
+            try {
+                this.sequence = Integer.parseInt(name.substring(idx + 1));
+                // If an exception occurred we misdetected a sequence suffix,
+                // so return -1.
+            } catch (NumberFormatException e) {
+                LOG.info("Number format exception for " + idx, e);
+            } catch (ArrayIndexOutOfBoundsException e) {
+               LOG.info("Array out of bounds for " + idx, e);
+            }
+        }
+    }
+
+    @Override
+    public String toString() {
+        return name.toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        ZNodeName sequence = (ZNodeName) o;
+
+        if (!name.equals(sequence.name)) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return name.hashCode() + 37;
+    }
+
+    public int compareTo(ZNodeName that) {
+        int answer = this.prefix.compareTo(that.prefix);
+        if (answer == 0) {
+            int s1 = this.sequence;
+            int s2 = that.sequence;
+            if (s1 == -1 && s2 == -1) {
+                return this.name.compareTo(that.name);
+            }
+            answer = s1 == -1 ? 1 : s2 == -1 ? -1 : s1 - s2;
+        }
+        return answer;
+    }
+
+    /**
+     * Returns the name of the znode
+     */
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Returns the sequence number
+     */
+    public int getZNodeName() {
+        return sequence;
+    }
+
+    /**
+     * Returns the text prefix before the sequence number
+     */
+    public String getPrefix() {
+        return prefix;
+    }
+}

+ 38 - 0
src/recipes/lock/src/java/org/apache/zookeeper/recipes/lock/ZooKeeperOperation.java

@@ -0,0 +1,38 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import org.apache.zookeeper.KeeperException;
+
+/**
+ * A callback object which can be used for implementing retry-able operations in the 
+ * {@link org.apache.zookeeper.recipes.lock.ProtocolSupport} class
+ *
+ */
+public interface ZooKeeperOperation {
+    
+    /**
+     * Performs the operation - which may be involved multiple times if the connection
+     * to ZooKeeper closes during this operation
+     *
+     * @return the result of the operation or null
+     * @throws KeeperException
+     * @throws InterruptedException
+     */
+    public boolean execute() throws KeeperException, InterruptedException;
+}

+ 151 - 0
src/recipes/lock/test/org/apache/zookeeper/recipes/lock/WriteLockTest.java

@@ -0,0 +1,151 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import org.apache.zookeeper.ZooKeeper;
+import org.apache.zookeeper.test.ClientBase;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * test for writelock
+ */
+public class WriteLockTest extends ClientBase {
+    protected int sessionTimeout = 10 * 1000;
+    protected String dir = "/" + getClass().getName();
+    protected WriteLock[] nodes;
+    protected CountDownLatch latch = new CountDownLatch(1);
+    private boolean restartServer = true;
+    private boolean workAroundClosingLastZNodeFails = true;
+    private boolean killLeader = true;
+
+    public void testRun() throws Exception {
+        runTest(3);
+    }
+
+    class LockCallback implements LockListener {
+        public void lockAcquired() {
+            latch.countDown();
+        }
+
+        public void lockReleased() {
+            
+        }
+        
+    }
+    protected void runTest(int count) throws Exception {
+        nodes = new WriteLock[count];
+        for (int i = 0; i < count; i++) {
+            ZooKeeper keeper = createClient();
+            WriteLock leader = new WriteLock(keeper, dir, null);
+            leader.setLockListener(new LockCallback());
+            nodes[i] = leader;
+
+            leader.lock();
+        }
+
+        // lets wait for any previous leaders to die and one of our new
+        // nodes to become the new leader
+        latch.await(30, TimeUnit.SECONDS);
+
+        WriteLock first = nodes[0];
+        dumpNodes(count);
+
+        // lets assert that the first election is the leader
+        assertTrue("The first znode should be the leader " + first.getId(), first.isOwner());
+
+        for (int i = 1; i < count; i++) {
+            WriteLock node = nodes[i];
+            assertFalse("Node should not be the leader " + node.getId(), node.isOwner());
+        }
+
+        if (count > 1) {
+            if (killLeader) {
+            System.out.println("Now killing the leader");
+            // now lets kill the leader
+            latch = new CountDownLatch(1);
+            first.unlock();
+            latch.await(30, TimeUnit.SECONDS);
+            //Thread.sleep(10000);
+            WriteLock second = nodes[1];
+            dumpNodes(count);
+            // lets assert that the first election is the leader
+            assertTrue("The second znode should be the leader " + second.getId(), second.isOwner());
+
+            for (int i = 2; i < count; i++) {
+                WriteLock node = nodes[i];
+                assertFalse("Node should not be the leader " + node.getId(), node.isOwner());
+            }
+            }
+
+
+            if (restartServer) {
+                // now lets stop the server
+                System.out.println("Now stopping the server");
+                stopServer();
+                Thread.sleep(10000);
+
+                // TODO lets assert that we are no longer the leader
+                dumpNodes(count);
+
+                System.out.println("Starting the server");
+                startServer();
+                Thread.sleep(10000);
+
+                for (int i = 0; i < count - 1; i++) {
+                    System.out.println("Calling acquire for node: " + i);
+                    nodes[i].lock();
+                }
+                dumpNodes(count);
+                System.out.println("Now closing down...");
+            }
+        }
+    }
+
+    protected void dumpNodes(int count) {
+        for (int i = 0; i < count; i++) {
+            WriteLock node = nodes[i];
+            System.out.println("node: " + i + " id: " + 
+                    node.getId() + " is leader: " + node.isOwner());
+        }
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        if (nodes != null) {
+            for (int i = 0; i < nodes.length; i++) {
+                WriteLock node = nodes[i];
+                if (node != null) {
+                    System.out.println("Closing node: " + i);
+                    node.close();
+                    if (workAroundClosingLastZNodeFails && i == nodes.length - 1) {
+                        System.out.println("Not closing zookeeper: " + i + " due to bug!");
+                    } else {
+                        System.out.println("Closing zookeeper: " + i);
+                        node.getZookeeper().close();
+                        System.out.println("Closed zookeeper: " + i);
+                    }
+                }
+            }
+        }
+        System.out.println("Now lets stop the server");
+        super.tearDown();
+
+    }
+}

+ 55 - 0
src/recipes/lock/test/org/apache/zookeeper/recipes/lock/ZNodeNameTest.java

@@ -0,0 +1,55 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.zookeeper.recipes.lock;
+
+import junit.framework.TestCase;
+
+import java.util.SortedSet;
+import java.util.TreeSet;
+
+/**
+ * test for znodenames
+ */
+public class ZNodeNameTest extends TestCase {
+    public void testOrderWithSamePrefix() throws Exception {
+        String[] names = { "x-3", "x-5", "x-11", "x-1" };
+        String[] expected = { "x-1", "x-3", "x-5", "x-11" };
+        assertOrderedNodeNames(names, expected);
+    }
+    public void testOrderWithDifferentPrefixes() throws Exception {
+        String[] names = { "r-3", "r-2", "r-1", "w-2", "w-1" };
+        String[] expected = { "r-1", "r-2", "r-3", "w-1", "w-2" };
+        assertOrderedNodeNames(names, expected);
+    }
+
+    protected void assertOrderedNodeNames(String[] names, String[] expected) {
+        int size = names.length;
+        assertEquals("The two arrays should be the same size!", names.length, expected.length);
+        SortedSet<ZNodeName> nodeNames = new TreeSet<ZNodeName>();
+        for (String name : names) {
+            nodeNames.add(new ZNodeName(name));
+        }
+
+        int index = 0;
+        for (ZNodeName nodeName : nodeNames) {
+            String name = nodeName.getName();
+            assertEquals("Node " + index, expected[index++], name);
+        }
+    }
+
+}