From 5348fe6bcba126301a3f97e3919f7eeca1b940ea Mon Sep 17 00:00:00 2001
From: Stefan Bodewig <bodewig@apache.org>
Date: Thu, 4 Sep 2008 14:57:04 +0000
Subject: [PATCH] symlink delete now works if the link points to a parent
 directory as well.  PR 45743.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@692081 13f79535-47bb-0310-9956-ffa450edef68
---
 WHATSNEW                                      |  4 ++++
 .../ant/taskdefs/optional/unix/Symlink.java   | 20 ++++++++++++++--
 .../antunit/core/dirscanner-symlinks-test.xml | 24 +++++--------------
 .../taskdefs/optional/unix/symlink-test.xml   |  6 +++++
 4 files changed, 34 insertions(+), 20 deletions(-)

diff --git a/WHATSNEW b/WHATSNEW
index 1f25ac778..5f3e810c9 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -196,6 +196,10 @@ Fixed bugs:
    contained line feeds some excess output ended up in Ant's log.
    Bugzilla Report 45411.
 
+ * <symlink action="delete"> failed to delete a link that pointed to
+   a parent directory.
+   Bugzilla Report 45743.
+
 Other changes:
 --------------
 
diff --git a/src/main/org/apache/tools/ant/taskdefs/optional/unix/Symlink.java b/src/main/org/apache/tools/ant/taskdefs/optional/unix/Symlink.java
index 0d2d2b2e5..c64b8225d 100644
--- a/src/main/org/apache/tools/ant/taskdefs/optional/unix/Symlink.java
+++ b/src/main/org/apache/tools/ant/taskdefs/optional/unix/Symlink.java
@@ -386,13 +386,19 @@ public class Symlink extends DispatchTask {
      * <p>This is a utility method that removes a unix symlink without removing
      * the resource that the symlink points to. If it is accidentally invoked
      * on a real file, the real file will not be harmed, but an exception
-     * will be thrown when the deletion is attempted. This method works by
+     * will be thrown when the deletion is attempted.</p>
+     *
+     * <p>Normaly this method works by
      * getting the canonical path of the link, using the canonical path to
      * rename the resource (breaking the link) and then deleting the link.
      * The resource is then returned to its original name inside a finally
      * block to ensure that the resource is unharmed even in the event of
      * an exception.</p>
      *
+     * <p>There may be cases where the algorithm described above doesn't work,
+     * in that case the method tries to use the native "rm" command on
+     * the symlink instead.</p>
+     *
      * <p>Since Ant 1.8.0 this method will try to delete the File object if
      * it reports it wouldn't exist (as symlinks pointing nowhere usually do). 
      * Prior version would throw a FileNotFoundException in that case.</p>
@@ -410,12 +416,22 @@ public class Symlink extends DispatchTask {
             linkfil.delete();
             return;
         }
+
         // find the resource of the existing link:
         File canfil = linkfil.getCanonicalFile();
 
         // rename the resource, thus breaking the link:
         File temp = FILE_UTILS.createTempFile("symlink", ".tmp",
-                                              canfil.getParentFile(), false, false);
+                                              canfil.getParentFile(), false,
+                                              false);
+
+        if (FILE_UTILS.isLeadingPath(canfil, linkfil)) {
+            // link points to a parent directory, renaming the parent
+            // will rename the file
+            linkfil = new File(temp,
+                               FILE_UTILS.removeLeadingPath(canfil, linkfil));
+        }
+
         try {
             try {
                 FILE_UTILS.rename(canfil, temp);
diff --git a/src/tests/antunit/core/dirscanner-symlinks-test.xml b/src/tests/antunit/core/dirscanner-symlinks-test.xml
index 17c6e2705..3e1251207 100644
--- a/src/tests/antunit/core/dirscanner-symlinks-test.xml
+++ b/src/tests/antunit/core/dirscanner-symlinks-test.xml
@@ -81,9 +81,7 @@
     <copy todir="${output}">
       <fileset dir="${base}" followsymlinks="true"/>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}/A"/>
-    </exec>
+    <symlink action="delete" link="${base}/A"/>
     <au:assertFileExists file="${output}/A/B/file.txt"/>
   </target>
 
@@ -95,9 +93,7 @@
         <include name="A/B/*"/>
       </fileset>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}/A"/>
-    </exec>
+    <symlink action="delete" link="${base}/A"/>
     <au:assertFileExists file="${output}/A/B/file.txt"/>
   </target>
 
@@ -110,9 +106,7 @@
         <include name="A/base/A/B/*"/>
       </fileset>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}/A"/>
-    </exec>
+    <symlink action="delete" link="${base}/A"/>
     <au:assertFileExists file="${output}/A/base/A/B/file.txt"/>
   </target>
 
@@ -122,9 +116,7 @@
     <copy todir="${output}">
       <fileset dir="${base}" followsymlinks="false"/>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}/A"/>
-    </exec>
+    <symlink action="delete" link="${base}/A"/>
     <au:assertFileDoesntExist file="${output}/A/B/file.txt"/>
   </target>
 
@@ -134,9 +126,7 @@
     <copy todir="${output}">
       <fileset dir="${base}" followsymlinks="true"/>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}"/>
-    </exec>
+    <symlink action="delete" link="${base}"/>
     <assertDirIsEmpty/>
   </target>
 
@@ -146,9 +136,7 @@
     <copy todir="${output}">
       <fileset dir="${base}" followsymlinks="false"/>
     </copy>
-    <exec executable="rm">
-      <arg file="${base}"/>
-    </exec>
+    <symlink action="delete" link="${base}"/>
     <assertDirIsEmpty/>
   </target>
 
diff --git a/src/tests/antunit/taskdefs/optional/unix/symlink-test.xml b/src/tests/antunit/taskdefs/optional/unix/symlink-test.xml
index 2a1cdfa02..91bd1651b 100644
--- a/src/tests/antunit/taskdefs/optional/unix/symlink-test.xml
+++ b/src/tests/antunit/taskdefs/optional/unix/symlink-test.xml
@@ -69,4 +69,10 @@
     <au:assertFileDoesntExist file="${output}/link"/>
   </target>
 
+  <target name="testDeleteLinkToParent" depends="init" if="unix">
+    <symlink link="${output}/link" resource="${output}"/>
+    <symlink link="${output}/link" action="delete"/>
+    <au:assertFileDoesntExist file="${output}/link"/>
+  </target>
+
 </project>