Add support for bsdiff of file system metadata blocks

test_utils.cc

Index: test_utils.cc
diff --git a/test_utils.cc b/test_utils.cc
index c1bdb48063f43bab01aef4852aa4ed4b262edb42..8ce4e56fafa0518169a5d03eca5d07ec2dddad65 100644
--- a/test_utils.cc
+++ b/test_utils.cc
@@ -178,6 +178,16 @@ void FillWithData(vector<char>* buffer) {
   }
 }
 
+void CreateEmptyExtImageAtPath(const string& path,
+                               size_t size,
+			       int block_size) {
+  EXPECT_EQ(0, System(StringPrintf("dd if=/dev/zero of=%s"
+                                   " seek=%Zu bs=1 count=1",

[petkov, 2010/12/10 00:46:55]

what's %Zu?

[thieule, 2010/12/14 23:11:21]

Looks like %Zu is outdated and the proper format is %zu for size_t.

+                                   path.c_str(), size)));
+  EXPECT_EQ(0, System(StringPrintf("mkfs.ext3 -b %d -F %s",

[petkov, 2010/12/10 00:46:55]

we use ext2 now, right?

[thieule, 2010/12/14 23:11:21]

This is a little bit more involved than just here.  I'll do the ext3 to ext2
change in a separate CL.

+                                   block_size, path.c_str())));
+}
+
 void CreateExtImageAtPath(const string& path, vector<string>* out_paths) {
   // create 10MiB sparse file
   EXPECT_EQ(0, System(StringPrintf("dd if=/dev/zero of=%s"