ENH: Added kwsys SystemTools::CreateSymlink and SystemTools::ReadSymlink.

Source/cmSystemTools.cxx

@@ -1376,20 +1376,6 @@ bool cmSystemTools::StringEndsWith(const char* str1, const char* str2)
   return !strncmp(str1 + (strlen(str1)-strlen(str2)), str2, strlen(str2));
 }
 
-#if defined(_WIN32) && !defined(__CYGWIN__)
-bool cmSystemTools::CreateSymlink(const char*, const char*)
-{
-  // Should we create a copy here?
-  return false;
-}
-#else
-bool cmSystemTools::CreateSymlink(const char* origName, const char* newName)
-{
-  return (symlink(origName, newName) >= 0);
-}
-#endif
-
-
 // compute the relative path from here to there
 std::string cmSystemTools::RelativePath(const char* local, const char* remote)
 {

Source/cmSystemTools.h

@@ -297,7 +297,6 @@ public:
   static std::string ConvertToRunCommandPath(const char* path);
   //! Check if the first string ends with the second one.
   static bool StringEndsWith(const char* str1, const char* str2);
-  static bool CreateSymlink(const char* origName, const char* newName);
   
   /** compute the relative path from local to remote.  local must 
       be a directory.  remote can be a file or a directory.  

Source/kwsys/SystemTools.cxx

@@ -2356,6 +2356,44 @@ bool SystemTools::FileIsSymlink(const char* name)
 #endif
 }
 
+#if defined(_WIN32) && !defined(__CYGWIN__)
+bool SystemTools::CreateSymlink(const char*, const char*)
+{
+  return false;
+}
+#else
+bool SystemTools::CreateSymlink(const char* origName, const char* newName)
+{
+  return symlink(origName, newName) >= 0;
+}
+#endif
+
+#if defined(_WIN32) && !defined(__CYGWIN__)
+bool SystemTools::ReadSymlink(const char*, kwsys_stl::string&)
+{
+  return false;
+}
+#else
+bool SystemTools::ReadSymlink(const char* newName,
+                              kwsys_stl::string& origName)
+{
+  char buf[KWSYS_SYSTEMTOOLS_MAXPATH+1];
+  int count =
+    static_cast<int>(readlink(newName, buf, KWSYS_SYSTEMTOOLS_MAXPATH));
+  if(count >= 0)
+    {
+    // Add null-terminator.
+    buf[count] = 0;
+    origName = buf;
+    return true;
+    }
+  else
+    {
+    return false;
+    }
+}
+#endif
+
 int SystemTools::ChangeDirectory(const char *dir)
 {
   return Chdir(dir);

Source/kwsys/SystemTools.hxx.in

@@ -588,6 +588,18 @@ public:
     unsigned long length = 256, 
     double percent_bin = 0.05);
 
+  /**
+   * Create a symbolic link if the platform supports it.  Returns whether
+   * creation succeded.
+   */
+  static bool CreateSymlink(const char* origName, const char* newName);
+
+  /**
+   * Read the contents of a symbolic link.  Returns whether reading
+   * succeded.
+   */
+  static bool ReadSymlink(const char* newName, kwsys_stl::string& origName);
+
   /**
    * Try to locate the file 'filename' in the directory 'dir'.
    * If 'filename' is a fully qualified filename, the basename of the file is