Introduce xmalloc and xrealloc to die gracefully with a descriptive
message when out of memory, rather than taking a SIGSEGV.
Signed-off-by: Christopher Li<chrislgit@chrisli.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We should _not_ mark a blob object "parsed" just because we
looked it up: it gets marked that way only once we've actually
seen it. Otherwise we can never notice a missing blob.