[PATCH] Fix in-place editing in crlf_to_git and ident_to_git.

[Pierre Habouzit <madcoder@debian.org>]

When crlf_to_git or ident_to_git are called "in place", the buffer already
is big enough and should not be resized (as it could make the buffer address
change, hence invalidate the `src' pointers !).

Also fix the growth length at the same time: we want to replace the buffer
content (not append) in those functions as they are filters.

Thanks to Bernt Hansen for the bug report.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
---

  This patch is done on top of master, as strbuf's have been merged.
This is a major issue.

 convert.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/convert.c b/convert.c
index 0d5e909..4664197 100644
--- a/convert.c
+++ b/convert.c
@@ -110,7 +110,9 @@ static int crlf_to_git(const char *path, const char *src, size_t len,
 			return 0;
 	}
 
-	strbuf_grow(buf, len);
+	/* only grow if not in place */
+	if (src != buf->buf)
+		strbuf_grow(buf, len - buf->len);
 	dst = buf->buf;
 	if (action == CRLF_GUESS) {
 		/*
@@ -281,12 +283,12 @@ static int apply_filter(const char *path, const char *src, size_t len,
 		ret = 0;
 	}
 	if (close(pipe_feed[0])) {
-		ret = error("read from external filter %s failed", cmd);
+		error("read from external filter %s failed", cmd);
 		ret = 0;
 	}
 	status = finish_command(&child_process);
 	if (status) {
-		ret = error("external filter %s failed %d", cmd, -status);
+		error("external filter %s failed %d", cmd, -status);
 		ret = 0;
 	}
 
@@ -422,7 +424,9 @@ static int ident_to_git(const char *path, const char *src, size_t len,
 	if (!ident || !count_ident(src, len))
 		return 0;
 
-	strbuf_grow(buf, len);
+	/* only grow if not in place */
+	if (src != buf->buf)
+		strbuf_grow(buf, len - buf->len);
 	dst = buf->buf;
 	for (;;) {
 		dollar = memchr(src, '$', len);
-- 
1.5.3.4.207.gc79d4-dirty