HADOOP-8954. stat executable not found on Windows. Contributed by Bikas Saha, and Ivan Mitic ported by Chris Narouth.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-trunk-win@1401528 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.branch-trunk-win.txt

@@ -14,3 +14,6 @@ branch-trunk-win changes - unreleased
   branch-trunk-win to enable initial test pass. (Raja Aluri, Davio Lao, 
   Sumadhur Reddy Bolli, Ahmed El Baz, Kanna Karanam, Chuan Liu, 
   Ivan Mitic, Chris Nauroth, and Bikas Saha via suresh)
+
+  HADOOP-8954. "stat" executable not found on Windows. (Bikas Saha, Ivan Mitic
+  ported by Chris Narouth via suresh)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/HardLink.java

@@ -25,9 +25,11 @@ import java.io.IOException;
 import java.io.InputStreamReader;
 import java.util.Arrays;
 
+import org.apache.hadoop.util.Shell;
+
 /**
  * Class for creating hardlinks.
- * Supports Unix/Linux, WinXP/2003/Vista via Cygwin, and Mac OS X.
+ * Supports Unix/Linux, Windows via winutils , and Mac OS X.
  * 
  * The HardLink class was formerly a static inner class of FSUtil,
  * and the methods provided were blatantly non-thread-safe.
@@ -41,7 +43,7 @@ public class HardLink {
 
   public enum OSType {
     OS_TYPE_UNIX,
-    OS_TYPE_WINXP,
+    OS_TYPE_WIN,
     OS_TYPE_SOLARIS,
     OS_TYPE_MAC
   }
@@ -55,7 +57,7 @@ public class HardLink {
   //methods without instantiating the HardLink object
   static { 
     osType = getOSType();
-    if (osType == OSType.OS_TYPE_WINXP) {
+    if (osType == OSType.OS_TYPE_WIN) {
       // Windows
       getHardLinkCommand = new HardLinkCGWin();
     } else {
@@ -79,14 +81,8 @@ public class HardLink {
   
   static private OSType getOSType() {
     String osName = System.getProperty("os.name");
-    if (osName.contains("Windows") &&
-            (osName.contains("XP") 
-            || osName.contains("2003") 
-            || osName.contains("Vista")
-            || osName.contains("Windows_7")
-            || osName.contains("Windows 7") 
-            || osName.contains("Windows7"))) {
-      return OSType.OS_TYPE_WINXP;
+    if (Shell.WINDOWS) {
+      return OSType.OS_TYPE_WIN;
     }
     else if (osName.contains("SunOS") 
             || osName.contains("Solaris")) {
@@ -266,14 +262,16 @@ public class HardLink {
     //unit testing (sort of) on non-Win servers
 
     static String[] hardLinkCommand = {
-                        "fsutil","hardlink","create", null, null};
+                        Shell.WINUTILS,"hardlink","create", null, null};
     static String[] hardLinkMultPrefix = {
                         "cmd","/q","/c","for", "%f", "in", "("};
     static String   hardLinkMultDir = "\\%f";
     static String[] hardLinkMultSuffix = {
-                        ")", "do", "fsutil", "hardlink", "create", null, 
+                        ")", "do", Shell.WINUTILS, "hardlink", "create", null,
                         "%f", "1>NUL"};
-    static String[] getLinkCountCommand = {"stat","-c%h", null};
+    static String[] getLinkCountCommand = {
+                        Shell.WINUTILS, "hardlink",
+                        "stat", null};
     //Windows guarantees only 8K - 1 bytes cmd length.
     //Subtract another 64b to allow for Java 'exec' overhead
     static final int maxAllowedCmdArgLength = 8*1024 - 65;
@@ -324,12 +322,6 @@ public class HardLink {
       String[] buf = new String[getLinkCountCommand.length];
       System.arraycopy(getLinkCountCommand, 0, buf, 0, 
                        getLinkCountCommand.length);
-      //The linkCount command is actually a Cygwin shell command,
-      //not a Windows shell command, so we should use "makeShellPath()"
-      //instead of "getCanonicalPath()".  However, that causes another
-      //shell exec to "cygpath.exe", and "stat.exe" actually can handle
-      //DOS-style paths (it just prints a couple hundred bytes of warning
-      //to stderr), so we use the more efficient "getCanonicalPath()".
       buf[getLinkCountCommand.length - 1] = file.getCanonicalPath();
       return buf;
     }
@@ -350,7 +342,7 @@ public class HardLink {
       //add the fixed overhead of the hardLinkMult command 
       //(prefix, suffix, and Dir suffix)
       sum += ("cmd.exe /q /c for %f in ( ) do "
-              + "fsutil hardlink create \\%f %f 1>NUL ").length();
+              + Shell.WINUTILS + " hardlink create \\%f %f 1>NUL ").length();
       return sum;
     }
     
@@ -577,14 +569,10 @@ public class HardLink {
   /* Create an IOException for failing to get link count. */
   private static IOException createIOException(File f, String message,
       String error, int exitvalue, Exception cause) {
-    
-    final String winErrMsg = "; Windows errors in getLinkCount are often due "
-         + "to Cygwin misconfiguration";
 
     final String s = "Failed to get link count on file " + f
         + ": message=" + message
         + "; error=" + error
-        + ((osType == OSType.OS_TYPE_WINXP) ? winErrMsg : "")
         + "; exit value=" + exitvalue;
     return (cause == null) ? new IOException(s) : new IOException(s, cause);
   }

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestHardLink.java

@@ -54,17 +54,6 @@ import static org.apache.hadoop.fs.HardLink.*;
  * NOTICE: This test class only tests the functionality of the OS
  * upon which the test is run! (although you're pretty safe with the
  * unix-like OS's, unless a typo sneaks in.)
- * 
- * Notes about Windows testing:  
- * (a) In order to create hardlinks, the process must be run with 
- * administrative privs, in both the account AND the invocation.
- * For instance, to run within Eclipse, the Eclipse application must be 
- * launched by right-clicking on it, and selecting "Run as Administrator" 
- * (and that option will only be available if the current user id does 
- * in fact have admin privs).
- * (b) The getLinkCount() test case will fail for Windows, unless Cygwin
- * is set up properly.  In particular, ${cygwin}/bin must be in
- * the PATH environment variable, so the cygwin utilities can be found.
  */
 public class TestHardLink {
   
@@ -221,9 +210,6 @@ public class TestHardLink {
    * Sanity check the simplest case of HardLink.getLinkCount()
    * to make sure we get back "1" for ordinary single-linked files.
    * Tests with multiply-linked files are in later test cases.
-   * 
-   * If this fails on Windows but passes on Unix, the most likely cause is 
-   * incorrect configuration of the Cygwin installation; see above.
    */
   @Test
   public void testGetLinkCount() throws IOException {
@@ -404,7 +390,7 @@ public class TestHardLink {
     assertEquals(5, win.hardLinkCommand.length); 
     assertEquals(7, win.hardLinkMultPrefix.length);
     assertEquals(8, win.hardLinkMultSuffix.length);
-    assertEquals(3, win.getLinkCountCommand.length);
+    assertEquals(4, win.getLinkCountCommand.length);
 
     assertTrue(win.hardLinkMultPrefix[4].equals("%f"));
     //make sure "%f" was not munged
@@ -415,7 +401,7 @@ public class TestHardLink {
     assertTrue(win.hardLinkMultSuffix[7].equals("1>NUL"));
     //make sure "1>NUL" was not munged
     assertEquals(5, ("1>NUL").length()); 
-    assertTrue(win.getLinkCountCommand[1].equals("-c%h"));
+    assertTrue(win.getLinkCountCommand[1].equals("hardlink"));
     //make sure "-c%h" was not munged
     assertEquals(4, ("-c%h").length()); 
   }