Mark places that need blob munging later for CRLF conversion.

Here's a patch that I think we can merge right now. There may be
other places that need this, but this at least points out the
three places that read/write working tree files for git
update-index, checkout and diff respectively. That should cover
a lot of it [jc: git-apply uses an entirely different codepath
both for reading and writing].

Some day we can actually implement it. In the meantime, this
points out a place for people to start. We *can* even start with
a really simple "we do CRLF conversion automatically, regardless
of filename" kind of approach, that just look at the data (all
three cases have the _full_ file data already in memory) and
says "ok, this is text, so let's convert to/from DOS format
directly".

THAT somebody can write in ten minutes, and it would already
make git much nicer on a DOS/Windows platform, I suspect.

And it would be totally zero-cost if you just make it a config
option (but please make it dynamic with the _default_ just being
0/1 depending on whether it's UNIX/Windows, just so that UNIX
people can _test_ it easily).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff.c

@@ -1364,6 +1364,7 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
 		s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
 		close(fd);
 		s->should_munmap = 1;
+		/* FIXME! CRLF -> LF conversion goes here, based on "s->path" */
 	}
 	else {
 		char type[20];

entry.c

@@ -89,6 +89,7 @@ static int write_entry(struct cache_entry *ce, char *path, struct checkout *stat
 			return error("git-checkout-index: unable to create file %s (%s)",
 				path, strerror(errno));
 		}
+		/* FIXME: LF -> CRLF conversion goes here, based on "ce->name" */
 		wrote = write_in_full(fd, new, size);
 		close(fd);
 		free(new);

sha1_file.c

@@ -2091,6 +2091,7 @@ int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, con
 
 	if (!type)
 		type = blob_type;
+	/* FIXME: CRLF -> LF conversion here for blobs! We'll need the path! */
 	if (write_object)
 		ret = write_sha1_file(buf, size, type, sha1);
 	else