From ee71b75133d3e515172b5fbe3dccf7d3906f5a19 Mon Sep 17 00:00:00 2001
From: KWSys Robot <kwrobot@kitware.com>
Date: Wed, 27 May 2015 13:15:22 -0400
Subject: [PATCH] KWSys 2015-05-27 (61e0419f)

Extract upstream KWSys using the following shell commands.

$ git archive --prefix=upstream-kwsys/ 61e0419f | tar x
$ git shortlog --no-merges --abbrev=8 --format='%h %s' b1d560a0..61e0419f
Brad King (1):
      61e0419f SystemTools: Teach RemoveFile to tolerate missing file

Matt McCormick (1):
      9a6b7c3f cmake: Set CMP0056 to NEW
---
 CMakeLists.txt      |  3 +++
 SystemTools.cxx     | 46 ++++++++++++++++++++++++++++++---------------
 testSystemTools.cxx | 18 ++++++++++++++++++
 3 files changed, 52 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8069ee294..c88e8880f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -88,6 +88,9 @@ CMAKE_MINIMUM_REQUIRED(VERSION 2.6.3 FATAL_ERROR)
 IF(POLICY CMP0025)
   CMAKE_POLICY(SET CMP0025 NEW)
 ENDIF()
+IF(POLICY CMP0056)
+  CMAKE_POLICY(SET CMP0056 NEW)
+ENDIF()
 
 #-----------------------------------------------------------------------------
 # If a namespace is not specified, use "kwsys" and enable testing.
diff --git a/SystemTools.cxx b/SystemTools.cxx
index 6c4a7a675..c834e34d1 100644
--- a/SystemTools.cxx
+++ b/SystemTools.cxx
@@ -2674,27 +2674,43 @@ kwsys_stl::string SystemTools::GetLastSystemError()
 bool SystemTools::RemoveFile(const kwsys_stl::string& source)
 {
 #ifdef _WIN32
-  mode_t mode;
-  if ( !SystemTools::GetPermissions(source, mode) )
+  kwsys_stl::wstring const& ws =
+    SystemTools::ConvertToWindowsExtendedPath(source);
+  if (DeleteFileW(ws.c_str()))
+    {
+    return true;
+    }
+  DWORD err = GetLastError();
+  if (err == ERROR_FILE_NOT_FOUND ||
+      err == ERROR_PATH_NOT_FOUND)
+    {
+    return true;
+    }
+  if (err != ERROR_ACCESS_DENIED)
     {
     return false;
     }
-  /* Win32 unlink is stupid --- it fails if the file is read-only  */
-  SystemTools::SetPermissions(source, S_IWRITE);
-#endif
-#ifdef _WIN32
-  bool res =
-    _wunlink(SystemTools::ConvertToWindowsExtendedPath(source).c_str()) == 0;
-#else
-  bool res = unlink(source.c_str()) != 0 ? false : true;
-#endif
-#ifdef _WIN32
-  if ( !res )
+  /* The file may be read-only.  Try adding write permission.  */
+  mode_t mode;
+  if (!SystemTools::GetPermissions(source, mode) ||
+      !SystemTools::SetPermissions(source, S_IWRITE))
     {
-    SystemTools::SetPermissions(source, mode);
+    SetLastError(err);
+    return false;
     }
+  if (DeleteFileW(ws.c_str()) ||
+      GetLastError() == ERROR_FILE_NOT_FOUND ||
+      GetLastError() == ERROR_PATH_NOT_FOUND)
+    {
+    return true;
+    }
+  /* Try to restore the original permissions.  */
+  SystemTools::SetPermissions(source, mode);
+  SetLastError(err);
+  return false;
+#else
+  return unlink(source.c_str()) == 0 || errno == ENOENT;
 #endif
-  return res;
 }
 
 bool SystemTools::RemoveADirectory(const kwsys_stl::string& source)
diff --git a/testSystemTools.cxx b/testSystemTools.cxx
index 42b62497b..15d8eab1b 100644
--- a/testSystemTools.cxx
+++ b/testSystemTools.cxx
@@ -156,6 +156,24 @@ static bool CheckFileOperations()
     res = false;
     }
 
+  kwsys_stl::string const testFileMissing(testNewDir + "/testMissingFile.txt");
+  if (!kwsys::SystemTools::RemoveFile(testFileMissing))
+    {
+    std::string const& msg = kwsys::SystemTools::GetLastSystemError();
+    kwsys_ios::cerr <<
+      "RemoveFile(\"" << testFileMissing << "\") failed: " << msg << "\n";
+    res = false;
+    }
+
+  kwsys_stl::string const testFileMissingDir(testNewDir + "/missing/file.txt");
+  if (!kwsys::SystemTools::RemoveFile(testFileMissingDir))
+    {
+    std::string const& msg = kwsys::SystemTools::GetLastSystemError();
+    kwsys_ios::cerr <<
+      "RemoveFile(\"" << testFileMissingDir << "\") failed: " << msg << "\n";
+    res = false;
+    }
+
   kwsys::SystemTools::Touch(testNewFile.c_str(), true);
   if (!kwsys::SystemTools::RemoveADirectory(testNewDir))
     {