Base: WritePlatformFile now retries the operation if

base/platform_file_unittest.cc

Index: base/platform_file_unittest.cc
===================================================================
--- base/platform_file_unittest.cc	(revision 97736)
+++ base/platform_file_unittest.cc	(working copy)
@@ -37,23 +37,7 @@
 // Returns the number of bytes written.
 int WriteFully(base::PlatformFile file, int64 offset,
                const char* data, int size) {
-  int total_bytes_written = 0;
-  int bytes_written;
-  while (total_bytes_written < size) {
-    bytes_written = base::WritePlatformFile(
-        file, offset + total_bytes_written, &data[total_bytes_written],
-        size - total_bytes_written);
-
-    if ((bytes_written == 0) && (size == 0))
-      return 0;
-
-    if ((bytes_written <= 0) || (bytes_written > size - total_bytes_written))
-      return -1;
-
-    total_bytes_written += bytes_written;
-  }
-
-  return total_bytes_written;

[Scott Hess - ex-Googler, 2011/08/25 21:05:23]

I'm kinda happy you're removing this code!

I'm kinda sad that nobody noticed that the problem being solved wasn't
restricted to unit tests.  Is there any possibility that short writes for
WritePlatformFile() were intentional?

I'm nervous about the test for "Wrote more bytes than I asked you to."  I assume
it wouldn't be there unless it happened, but WTF?

[rvargas (doing something else), 2011/08/25 21:28:06]

I looked at all the callers of this code and only one has a loop, but I'm not
changing that one because it is a weird loop that writes in chunks of 1k (no
idea why).

I don't really know why someone would want to ask to write x and be happy if
only y was written... the current callers just fail whatever they are doing.
That beats me too. The first version of this code has that check and there is no
comment on the CL, so I guess it was just extremely defensive code (as in fail
the test if this ever happens). But if it happens, the test will still fail.

+  return base::WritePlatformFile(file, offset, data, size);
 }
 
 } // namespace