Upstream android file related code.

base/base_paths_android.cc

+// Copyright (c) 2011 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 "base/base_paths.h"
+
+#include <unistd.h>
+
+#include "base/logging.h"
+#include "base/android_os.h"

[darin (slow to review), 2011/06/20 18:44:01]

this CL does not have this android_os.h file, and i don't see that in the tree. 
is it in a different CL that i can see?  it might help to be able to reference
it when reviewing this code.

[michaelbai, 2011/06/20 22:50:36]

I will provide it in next CL.

+
+namespace base {
+
+const char kSelfExe[] = "/proc/self/exe";
+
+bool PathProviderAndroid(int key, FilePath* result) {
+  switch (key) {
+    case base::FILE_EXE: {
+      char bin_dir[PATH_MAX + 1];
+      int bin_dir_size = readlink(kSelfExe, bin_dir, PATH_MAX);
+      if (bin_dir_size < 0 || bin_dir_size > PATH_MAX) {
+        NOTREACHED() << "Unable to resolve " << kSelfExe << ".";
+        return false;
+      }
+      bin_dir[bin_dir_size] = 0;
+      *result = FilePath(bin_dir);
+      return true;
+    }
+    case base::FILE_MODULE:
+      NOTIMPLEMENTED();
+      return false;
+    case base::DIR_MODULE: {

[darin (slow to review), 2011/06/20 18:44:01]

this is supposed to be directory of the currently executing code.  are you sure
this GetLibDirectory does that?  judging by the name, i'd guess not.  maybe a
TODO comment is at least warranted if you don't care about the distinction in
practice?

by the way, it can make it difficult for other developers to make use of
DIR_MODULE in new ways if it is not properly implemented.

[michaelbai, 2011/06/20 22:50:36]

As we discussed, implemented FILE_MODULE and used default implementation for
DIR_MODULE

+      AndroidOS* aos = AndroidOS::GetSharedInstance();
+      DCHECK(aos);
+      *result = aos->GetLibDirectory();
+      return true;
+    }
+    case base::DIR_SOURCE_ROOT:
+      // This const is only used for tests. Files in this directory are pushed
+      // to the device via android_run_test.sh.

[darin (slow to review), 2011/06/20 18:44:01]

android_run_test.sh is also not part of this CL.  be careful about adding
comments that refer to files.  they can become easily stale.

[michaelbai, 2011/06/20 22:50:36]

Done.

+      *result = FilePath(FILE_PATH_LITERAL("/data/local/tmp/"));
+      return true;
+    case base::DIR_CACHE: {
+      AndroidOS* aos = AndroidOS::GetSharedInstance();
+      DCHECK(aos);
+      *result = aos->GetCacheDirectory();
+      return true;
+    }
+    default:
+      // Note: the path system expects this function to override the default
+      // behavior. So no need to log an error if we don't support a given
+      // path. The system will just use the default.
+      return false;
+  }
+}
+
+}  // namespace base