When a directory contains read-only files, try to make them writable when recursively deleting on W…

runtime/bin/directory_win.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "bin/directory.h"
 
 #include <errno.h>
 #include <sys/stat.h>
 
 #include "bin/platform.h"
@@ skipping 180 matching lines @@
 static bool DeleteFile(char* file_name,
                        char* path,
                        int path_length) {
   size_t written = snprintf(path + path_length,
                             MAX_PATH - path_length,
                             "%s",
                             file_name);
   if (written != strlen(file_name)) {
     return false;
   }
-  return (DeleteFile(path) != 0);
+
+  if (DeleteFile(path) != 0) {
+    return true;
+  }
+
+  // If we failed because the file is read-only, make it writeable and try
+  // again. This mirrors Linux/Mac where a directory containing read-only files
+  // can still be recursively deleted.
+  if (GetLastError() == ERROR_ACCESS_DENIED) {
+    DWORD attributes = GetFileAttributes(path);
+    if (attributes == INVALID_FILE_ATTRIBUTES) {
+      return false;
+    }
+
+    if ((attributes & FILE_ATTRIBUTE_READONLY) == FILE_ATTRIBUTE_READONLY) {
+      attributes &= ~FILE_ATTRIBUTE_READONLY;
+
+      if (SetFileAttributes(path, attributes) == 0) {
+        return false;
+      }
+
+      return DeleteFile(path) != 0;
+    }
+  }
 }
 
 
 static bool DeleteDir(char* dir_name,
                       char* path,
                       int path_length) {
   if (strcmp(dir_name, ".") != 0 &&
       strcmp(dir_name, "..") != 0) {
     size_t written = snprintf(path + path_length,
                               MAX_PATH - path_length,
                               "%s",
                               dir_name);
     if (written != strlen(dir_name)) {
       return false;
     }
     return DeleteRecursively(path);
   }
   return true;
 }
 
 
 static bool DeleteEntry(LPWIN32_FIND_DATA find_file_data,
                         char* path,
                         int path_length) {
   DWORD attributes = find_file_data->dwFileAttributes;
+
   if ((attributes & FILE_ATTRIBUTE_DIRECTORY) != 0) {
     return DeleteDir(find_file_data->cFileName, path, path_length);
   } else {
     return DeleteFile(find_file_data->cFileName, path, path_length);
   }
 }
 
 
 static bool DeleteRecursively(const char* dir_name) {
   // If the directory is a junction, it's pointing to some other place in the
@@ skipping 163 matching lines @@
   // MoveFile does not allow replacing exising directories. Therefore,
   // if the new_path is currently a directory we need to delete it
   // first.
   if (new_exists == EXISTS) {
     bool success = DeleteRecursively(new_path);
     if (!success) return false;
   }
   DWORD flags = MOVEFILE_WRITE_THROUGH;
   return (MoveFileEx(path, new_path, flags) != 0);
 }