Make sure we close the file_handle when we create (but not open) a new file

1. Add FileUtilProxy::Create that does not leave a file_handle opened.
2. Update the file_util_operation to use FileUtilProxy::Create instead of FileUtilProxy::CreateOrOpen so that no other tasks get queued in before we close the handle.

BUG=58424,58473
TEST=fast/filesystem/

Review URL: http://codereview.chromium.org/3717001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62192 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 29 insertions, 1 deletions

diff --git a/base/file_util_proxy.cc b/base/file_util_proxy.cc
index b3b18f8..9cfff63 100644
--- a/base/file_util_proxy.cc
+++ b/base/file_util_proxy.cc
@@ -119,12 +119,14 @@ class RelayCreateOrOpen : public MessageLoopRelay {
       scoped_refptr<base::MessageLoopProxy> message_loop_proxy,
       const FilePath& file_path,
       int file_flags,
+      bool return_no_handle,
       base::FileUtilProxy::CreateOrOpenCallback* callback)
       : message_loop_proxy_(message_loop_proxy),
         file_path_(file_path),
         file_flags_(file_flags),
         callback_(callback),
         file_handle_(base::kInvalidPlatformFileValue),
+        return_no_handle_(return_no_handle),
         created_(false) {
     DCHECK(callback);
   }
@@ -139,6 +141,13 @@ class RelayCreateOrOpen : public MessageLoopRelay {
     base::PlatformFileError error_code = base::PLATFORM_FILE_OK;
     file_handle_ = base::CreatePlatformFile(file_path_, file_flags_,
                                             &created_, &error_code);
+    // If the return_no_handle is true the caller is not interested
+    // in the file_handle_.  Close it right now.
+    if (return_no_handle_ && file_handle_ != base::kInvalidPlatformFileValue) {
+      // We don't check the return value here.
+      base::ClosePlatformFile(file_handle_);
+      file_handle_ = base::kInvalidPlatformFileValue;
+    }
     set_error_code(error_code);
   }
 
@@ -154,6 +163,7 @@ class RelayCreateOrOpen : public MessageLoopRelay {
   int file_flags_;
   base::FileUtilProxy::CreateOrOpenCallback* callback_;
   base::PlatformFile file_handle_;
+  bool return_no_handle_;
   bool created_;
 };
 
@@ -680,7 +690,18 @@ bool FileUtilProxy::CreateOrOpen(
     const FilePath& file_path, int file_flags,
     CreateOrOpenCallback* callback) {
   return Start(FROM_HERE, message_loop_proxy, new RelayCreateOrOpen(
-      message_loop_proxy, file_path, file_flags, callback));
+      message_loop_proxy, file_path, file_flags, false /* return_no_handle */,
+      callback));
+}
+
+// static
+bool FileUtilProxy::Create(
+    scoped_refptr<MessageLoopProxy> message_loop_proxy,
+    const FilePath& file_path, int file_flags,
+    CreateOrOpenCallback* callback) {
+  return Start(FROM_HERE, message_loop_proxy, new RelayCreateOrOpen(
+      message_loop_proxy, file_path, file_flags, true /* return_no_handle */,
+      callback));
 }
 
 // static
diff --git a/base/file_util_proxy.h b/base/file_util_proxy.h
index e716ab7..11fc988 100644
--- a/base/file_util_proxy.h
+++ b/base/file_util_proxy.h
@@ -48,6 +48,13 @@ class FileUtilProxy {
                            int file_flags,
                            CreateOrOpenCallback* callback);
 
+  // Creates a file with the given flags.  This one is a variation of
+  // CreateOrOpen but it doesn't return a file handle.
+  static bool Create(scoped_refptr<MessageLoopProxy> message_loop_proxy,
+                     const FilePath& file_path,
+                     int file_flags,
+                     CreateOrOpenCallback* callback);
+
   // Creates a temporary file for writing.  The path and an open file handle
   // are returned.  It is invalid to pass NULL for the callback.
   typedef Callback3<base::PlatformFileError /* error code */,