pathspec: apply "*.c" optimization from exclude

When a pattern contains only a single asterisk as wildcard,
e.g. "foo*bar", after literally comparing the leading part "foo" with
the string, we can compare the tail of the string and make sure it
matches "bar", instead of running fnmatch() on "*bar" against the
remainder of the string.

-O2 build on linux-2.6, without the patch:

$ time git rev-list --quiet HEAD -- '*.c'

real    0m40.770s
user    0m40.290s
sys     0m0.256s

With the patch

$ time ~/w/git/git rev-list --quiet HEAD -- '*.c'

real    0m34.288s
user    0m33.997s
sys     0m0.205s

The above command is not supposed to be widely popular. It's chosen
because it exercises pathspec matching a lot. The point is it cuts
down matching time for popular patterns like *.c, which could be used
as pathspec in other places.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nguyễn Thái Ngọc Duy 2012-11-24 11:33:50 +07:00 committed by Junio C Hamano
parent 5d74762d87
commit 8c6abbcd27
4 changed files with 24 additions and 4 deletions

View File

@ -473,6 +473,8 @@ extern int index_name_is_other(const struct index_state *, const char *, int);
extern int ie_match_stat(const struct index_state *, struct cache_entry *, struct stat *, unsigned int);
extern int ie_modified(const struct index_state *, struct cache_entry *, struct stat *, unsigned int);
#define PATHSPEC_ONESTAR 1 /* the pathspec pattern sastisfies GFNM_ONESTAR */
struct pathspec {
const char **raw; /* get_pathspec() result, not freed by free_pathspec() */
int nr;
@ -483,6 +485,7 @@ struct pathspec {
const char *match;
int len;
int nowildcard_len;
int flags;
} *items;
};

18
dir.c
View File

@ -46,6 +46,13 @@ inline int git_fnmatch(const char *pattern, const char *string,
pattern += prefix;
string += prefix;
}
if (flags & GFNM_ONESTAR) {
int pattern_len = strlen(++pattern);
int string_len = strlen(string);
return string_len < pattern_len ||
strcmp(pattern,
string + string_len - pattern_len);
}
return fnmatch(pattern, string, fnm_flags);
}
@ -246,7 +253,9 @@ static int match_pathspec_item(const struct pathspec_item *item, int prefix,
}
if (item->nowildcard_len < item->len &&
!git_fnmatch(match, name, 0, item->nowildcard_len - prefix))
!git_fnmatch(match, name,
item->flags & PATHSPEC_ONESTAR ? GFNM_ONESTAR : 0,
item->nowildcard_len - prefix))
return MATCHED_FNMATCH;
return 0;
@ -1446,8 +1455,13 @@ int init_pathspec(struct pathspec *pathspec, const char **paths)
item->match = path;
item->len = strlen(path);
item->nowildcard_len = simple_length(path);
if (item->nowildcard_len < item->len)
item->flags = 0;
if (item->nowildcard_len < item->len) {
pathspec->has_wildcard = 1;
if (path[item->nowildcard_len] == '*' &&
no_wildcard(path + item->nowildcard_len + 1))
item->flags |= PATHSPEC_ONESTAR;
}
}
qsort(pathspec->items, pathspec->nr,

1
dir.h
View File

@ -143,6 +143,7 @@ extern int fnmatch_icase(const char *pattern, const char *string, int flags);
* The prefix part of pattern must not contains wildcards.
*/
#define GFNM_PATHNAME 1 /* similar to FNM_PATHNAME */
#define GFNM_ONESTAR 2 /* there is only _one_ wildcard, a star */
extern int git_fnmatch(const char *pattern, const char *string,
int flags, int prefix);

View File

@ -628,7 +628,8 @@ enum interesting tree_entry_interesting(const struct name_entry *entry,
if (item->nowildcard_len < item->len) {
if (!git_fnmatch(match + baselen, entry->path,
0, item->nowildcard_len - baselen))
item->flags & PATHSPEC_ONESTAR ? GFNM_ONESTAR : 0,
item->nowildcard_len - baselen))
return entry_interesting;
/*
@ -654,7 +655,8 @@ match_wildcards:
strbuf_add(base, entry->path, pathlen);
if (!git_fnmatch(match, base->buf + base_offset,
0, item->nowildcard_len)) {
item->flags & PATHSPEC_ONESTAR ? GFNM_ONESTAR : 0,
item->nowildcard_len)) {
strbuf_setlen(base, base_offset + baselen);
return entry_interesting;
}