name-hash: stop storing trailing '/' on paths in index_state.dir_hash

When 5102c617 (Add case insensitivity support for directories when using
git status, 2010-10-03) added directories to the name-hash there was
only a single hash table in which both real cache entries and leading
directory prefixes were registered. To distinguish between the two types
of entries, directories were stored with a trailing '/'.

2092678c (name-hash.c: fix endless loop with core.ignorecase=true,
2013-02-28), however, moved directories to a separate hash table
(index_state.dir_hash) but retained the (now) redundant trailing '/',
thus callers continue to bear the burden of ensuring the slash's
presence before searching the index for a directory. Eliminate this
redundancy by storing paths in the dir-hash without the trailing '/'.

An important benefit of this change is that it eliminates undocumented
and dangerous behavior of dir.c:directory_exists_in_index_icase() in
which it assumes not only that it can validly access one character
beyond the end of its incoming directory argument, but also that that
character will unconditionally be a '/'. This perilous behavior was
"tolerated" because the string passed in by its lone caller always had a
'/' in that position, however, things broke [1] when 2eac2a4c (ls-files
-k: a directory only can be killed if the index has a non-directory,
2013-08-15) added a new caller which failed to respect the undocumented
assumption.

[1]: http://thread.gmane.org/gmane.comp.version-control.git/232727

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Eric Sunshine
2013-09-17 03:06:16 -04:00
committed by Junio C Hamano
parent ebbd7439b1
commit d28eec2673
3 changed files with 8 additions and 7 deletions

2
dir.c
View File

@ -889,7 +889,7 @@ enum exist_status {
*/
static enum exist_status directory_exists_in_index_icase(const char *dirname, int len)
{
const struct cache_entry *ce = cache_dir_exists(dirname, len + 1);
const struct cache_entry *ce = cache_dir_exists(dirname, len);
unsigned char endchar;
if (!ce)