@matheusbsbs / matheus-bagliano / commits / d28eec2673

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>

Eric Sunshine committed Sep 17, 2013 at 03:06 UTC d28eec267374c476de490bff736a627da94575c5

3 files changed +8 -7

dir.c

+1 -1

@@ -889,7 +889,7 @@ enum exist_status {

889 */

890 static enum exist_status directory_exists_in_index_icase(const char *dirname, int len)

891 {

892 - const struct cache_entry *ce = cache_dir_exists(dirname, len + 1);

892 + const struct cache_entry *ce = cache_dir_exists(dirname, len);

893 unsigned char endchar;

894

895 if (!ce)

name-hash.c

+6 -5

@@ -58,9 +58,9 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,

58 {

59 /*

60 * Throw each directory component in the hash for quick lookup

61 - * during a git status. Directory components are stored with their

61 + * during a git status. Directory components are stored without their

62 * closing slash. Despite submodules being a directory, they never

63 - * reach this point, because they are stored without a closing slash

63 + * reach this point, because they are stored

64 * in index_state.name_hash (as ordinary cache_entries).

65 *

66 * Note that the cache_entry stored with the dir_entry merely

@@ -78,6 +78,7 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,

78 namelen--;

79 if (namelen <= 0)

80 return NULL;

81 + namelen--;

83 /* lookup existing entry for that directory */

84 dir = find_dir_entry(istate, ce->name, namelen);

@@ -97,7 +98,7 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate,

98 }

100 /* recursively add missing parent directories */

100 - dir->parent = hash_dir_entry(istate, ce, namelen - 1);

101 + dir->parent = hash_dir_entry(istate, ce, namelen);

102 }

103 return dir;

104 }

@@ -237,7 +238,7 @@ struct cache_entry *index_dir_exists(struct index_state *istate, const char *nam

238 * in the dir-hash, submodules are stored in the name-hash, so check

239 * there, as well.

240 */

240 - ce = index_file_exists(istate, name, namelen - 1, 1);

241 + ce = index_file_exists(istate, name, namelen, 1);

242 if (ce && S_ISGITLINK(ce->ce_mode))

243 return ce;

244

@@ -265,7 +266,7 @@ struct cache_entry *index_file_exists(struct index_state *istate, const char *na

266 struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int icase)

267 {

268 if (namelen > 0 && name[namelen - 1] == '/')

268 - return index_dir_exists(istate, name, namelen);

269 + return index_dir_exists(istate, name, namelen - 1);

270 return index_file_exists(istate, name, namelen, icase);

271 }

272

read-cache.c

+1 -1

@@ -643,7 +643,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,

643 if (*ptr == '/') {

644 struct cache_entry *foundce;

645 ++ptr;

646 - foundce = index_dir_exists(istate, ce->name, ptr - ce->name);

646 + foundce = index_dir_exists(istate, ce->name, ptr - ce->name - 1);

647 if (foundce) {

648 memcpy((void *)startPtr, foundce->name + (startPtr - ce->name), ptr - startPtr);

649 startPtr = ptr;