Fix a bug in file_util::Delete() where symlinks are not handled right

With this patch, file_util::Delete() uses lstat64() instead of stat64(), so that Delete() checks the existence of the symbolic link itself not a file pointed by the symlink. This allows us to delete a symbolic link when it points to a non-existent file. 

BUG=119430
TEST=base_unittests::FileUtilTest.* passes.

Review URL: https://chromiumcodereview.appspot.com/10690047

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@145060 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 7122db29d3965050505f7294f073d83f80ea7835
diff --git a/base/file_util_unittest.cc b/base/file_util_unittest.cc
index ea8918b..55f2039 100644
--- a/base/file_util_unittest.cc
+++ b/base/file_util_unittest.cc
@@ -744,6 +744,48 @@
   EXPECT_FALSE(file_util::PathExists(file_name));
 }
 
+#if defined(OS_POSIX)
+TEST_F(FileUtilTest, DeleteSymlinkToExistentFile) {
+  // Create a file
+  FilePath file_name = temp_dir_.path().Append(FPL("Test DeleteFile 2.txt"));
+  CreateTextFile(file_name, bogus_content);
+  ASSERT_TRUE(file_util::PathExists(file_name));
+
+  // Create a symlink to the file
+  FilePath file_link = temp_dir_.path().Append("file_link_2");
+  ASSERT_TRUE(file_util::CreateSymbolicLink(file_name, file_link))
+      << "Failed to create symlink.";
+
+  // Delete the symbolic link
+  EXPECT_TRUE(file_util::Delete(file_link, false));
+
+  // Make sure original file is not deleted
+  EXPECT_FALSE(file_util::PathExists(file_link));
+  EXPECT_TRUE(file_util::PathExists(file_name));
+}
+
+TEST_F(FileUtilTest, DeleteSymlinkToNonExistentFile) {
+  // Create a non-existent file path
+  FilePath non_existent = temp_dir_.path().Append(FPL("Test DeleteFile 3.txt"));
+  EXPECT_FALSE(file_util::PathExists(non_existent));
+
+  // Create a symlink to the non-existent file
+  FilePath file_link = temp_dir_.path().Append("file_link_3");
+  ASSERT_TRUE(file_util::CreateSymbolicLink(non_existent, file_link))
+      << "Failed to create symlink.";
+
+  // Make sure the symbolic link is exist
+  EXPECT_TRUE(file_util::IsLink(file_link));
+  EXPECT_FALSE(file_util::PathExists(file_link));
+
+  // Delete the symbolic link
+  EXPECT_TRUE(file_util::Delete(file_link, false));
+
+  // Make sure the symbolic link is deleted
+  EXPECT_FALSE(file_util::IsLink(file_link));
+}
+#endif  // defined(OS_POSIX)
+
 #if defined(OS_WIN)
 // Tests that the Delete function works for wild cards, especially
 // with the recursion flag.  Also coincidentally tests PathExists.