Merge "Fix infinite loop when using extents."

am: db7f0c8

* commit 'db7f0c891478b726567611468a65453a14f80559':
  Fix infinite loop when using extents.

Change-Id: I6a7899619fea9e31a84e99c12c753a722fd5aac7

bspatch.cc

@@ -112,7 +112,7 @@ bool WriteAll(const std::unique_ptr<FileInterface>& file,
               size_t size) {
   size_t offset = 0, written;
   while (offset < size) {
-    if (!file->Write(data + offset, size - offset, &written))
+    if (!file->Write(data + offset, size - offset, &written) || written == 0)
       return false;
     offset += written;
   }

memory_file.cc

@@ -35,6 +35,9 @@ bool MemoryFile::Seek(off_t pos) {
 bool MemoryFile::Close() {
   if (!WriteAll(file_, buffer_.data(), buffer_.size()))
     return false;
+  // Prevent writing |buffer_| to |file_| again if Close() is called more than
+  // once.
+  buffer_.clear();
   return file_->Close();
 }