Avoid fragmenting the heap too much while reconstructing the index.

net/disk_cache/simple/simple_index_file_posix.cc

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/disk_cache/simple/simple_index_file.h"
+
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace disk_cache {
+namespace {
+
+struct DirCloser {
+  void operator()(DIR* dir) { closedir(dir); }
+};
+
+typedef scoped_ptr<DIR, DirCloser> ScopedDir;
+
+}  // namespace
+
+// static
+bool SimpleIndexFile::TraverseCacheDirectory(
+    const base::FilePath& cache_path,
+    const EntryFileCallback& entry_file_callback) {
+  const ScopedDir dir(opendir(cache_path.value().c_str()));

[pasko, 2013/08/21 16:03:17]

this would closedir(NULL) if opendir() failed, is it intentional?

[Philippe, 2013/08/21 16:20:58]

Yeah, it is :) scoped_ptr<>.reset() only calls the deleter if the pointer is
non-null. But good catch anyway :)

[pasko, 2013/08/21 16:29:28]

thanks for explanation!

+  if (!dir) {
+    PLOG(ERROR) << "opendir " << cache_path.value();

[pasko, 2013/08/21 16:03:17]

I believe you can do:

PLOG(ERROR) << "opendir";

perror would print the file name (I did not check manually with PLOG though)

[Philippe, 2013/08/21 16:20:58]

Are you sure perror() prints the filename? To me it was just mapping errno to a
string. I'm 99% sure it doesn't print the name. And I did see a few of my
PLOG(ERROR) messages printed correctly (i.e. with a single occurrence of the
file path).

[pasko, 2013/08/21 16:29:28]

you are right, it does not print the dir name for opendir failures, ugh

+    return false;
+  }
+  dirent entry, *result;
+  while (readdir_r(dir.get(), &entry, &result) == 0) {
+    if (!result)
+      return true;  // The traversal completed successfully.
+    const std::string file_name(result->d_name);
+    if (file_name == "." || file_name == "..")
+      continue;
+    const base::FilePath file_path = cache_path.Append(
+        base::FilePath(file_name));
+    entry_file_callback.Run(file_path);
+  }
+  PLOG(ERROR) << "readdir_r " << cache_path.value();
+  return false;
+}
+
+}  // namespace disk_cache