ZOOKEEPER-3067: Optionally disable client environment logging.

Although logging the client environment at initialization can be
helpful for filing bug reports, it tends not to be that helpful
for internal applications. It also introduces a dependency on UID
lookups (via getlogin) that application otherwise may not desire.

Author: James Peach <jpeach@apache.org>

Reviewers: breed@apache.org, andor@apache.org

Closes #565 from jpeach/ZOOKEEPER-3067

src/c/CMakeLists.txt

@@ -216,7 +216,8 @@ set(test_sources
   tests/TestWatchers.cc
   tests/TestClient.cc
   tests/ZooKeeperQuorumServer.cc
-  tests/TestReadOnlyClient.cc)
+  tests/TestReadOnlyClient.cc
+  tests/TestLogClientEnv.cc)
 
 if(WANT_SYNCAPI)
   list(APPEND test_sources tests/PthreadMocks.cc)

src/c/Makefile.am

@@ -98,7 +98,7 @@ TEST_SOURCES = \
 	tests/TestZookeeperClose.cc \
 	tests/TestReconfig.cc \
 	tests/TestReconfigServer.cc \
-    tests/TestClientRetry.cc \
+	tests/TestClientRetry.cc \
 	tests/TestOperations.cc \
 	tests/TestMulti.cc \
 	tests/TestWatchers.cc \
@@ -106,6 +106,7 @@ TEST_SOURCES = \
 	tests/ZooKeeperQuorumServer.cc \
 	tests/ZooKeeperQuorumServer.h \
 	tests/TestReadOnlyClient.cc \
+	tests/TestLogClientEnv.cc \
 	$(NULL)
 
 if SOLARIS

src/c/include/zookeeper.h

@@ -158,6 +158,9 @@ extern ZOOAPI const int ZOO_PERM_ALL;
 /* flags for zookeeper_init{,2} */
 #define ZOO_READONLY         1
 
+/** Disable logging of the client environment at initialization time. */
+#define ZOO_NO_LOG_CLIENTENV 2
+
 /** This Id represents anyone. */
 extern ZOOAPI struct Id ZOO_ANYONE_ID_UNSAFE;
 /** This Id is only usable to set ACLs. It will get substituted with the

src/c/src/zookeeper.c

@@ -1139,7 +1139,10 @@ static zhandle_t *zookeeper_init_internal(const char *host, watcher_fn watcher,
 
     // Set log callback before calling into log_env
     zh->log_callback = log_callback;
-    log_env(zh);
+
+    if (!(flags & ZOO_NO_LOG_CLIENTENV)) {
+        log_env(zh);
+    }
 
 #ifdef _WIN32
     if (Win32WSAStartup()){

src/c/tests/TestLogClientEnv.cc

@@ -0,0 +1,59 @@
+/**
+ * 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 "CppAssertHelper.h"
+
+#include <string.h>
+#include <zookeeper.h>
+
+class Zookeeper_logClientEnv : public CPPUNIT_NS::TestFixture {
+    CPPUNIT_TEST_SUITE(Zookeeper_logClientEnv);
+    CPPUNIT_TEST(testLogClientEnv);
+    CPPUNIT_TEST_SUITE_END();
+
+    static void log_no_clientenv(const char *message) {
+      CPPUNIT_ASSERT(::strstr(message, "Client environment") == NULL);
+    }
+
+    static void log_clientenv(const char *message) {
+      static int first;
+
+      if (!first) {
+        CPPUNIT_ASSERT(::strstr(message, "Client environment") != NULL);
+        first = 1;
+      }
+    }
+
+public:
+
+    void testLogClientEnv() {
+      zhandle_t* zh;
+
+      zh = zookeeper_init2("localhost:22181", NULL, 0, NULL, NULL, 0, log_clientenv);
+      CPPUNIT_ASSERT(zh != 0);
+      zookeeper_close(zh);
+
+      zh = zookeeper_init2("localhost:22181", NULL, 0, NULL, NULL, ZOO_NO_LOG_CLIENTENV, log_no_clientenv);
+      CPPUNIT_ASSERT(zh != 0);
+      zookeeper_close(zh);
+    }
+};
+
+CPPUNIT_TEST_SUITE_REGISTRATION(Zookeeper_logClientEnv);
+