git-commit-vandalism/tree-walk.h
Linus Torvalds 304de2d2d6 Avoid unnecessary strlen() calls
This is a micro-optimization that grew out of the mailing list discussion
about "strlen()" showing up in profiles.

We used to pass regular C strings around to the low-level tree walking
routines, and while this worked fine, it meant that we needed to call
strlen() on strings that the caller always actually knew the size of
anyway.

So pass the length of the string down wih the string, and avoid
unnecessary calls to strlen(). Also, when extracting a pathname from a
tree entry, use "tree_entry_len()" instead of strlen(), since the length
of the pathname is directly calculable from the decoded tree entry itself
without having to actually do another strlen().

This shaves off another ~5-10% from some loads that are very tree
intensive (notably doing commit filtering by a pathspec).

Signed-off-by: Linus Torvalds  <torvalds@linux-foundation.org>"
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-18 15:36:59 -07:00

36 lines
987 B
C

#ifndef TREE_WALK_H
#define TREE_WALK_H
struct tree_desc {
const void *buf;
unsigned long size;
};
struct name_entry {
const unsigned char *sha1;
const char *path;
unsigned int mode;
int pathlen;
};
static inline int tree_entry_len(const char *name, const unsigned char *sha1)
{
return (char *)sha1 - (char *)name - 1;
}
void update_tree_entry(struct tree_desc *);
const unsigned char *tree_entry_extract(struct tree_desc *, const char **, unsigned int *);
/* Helper function that does both of the above and returns true for success */
int tree_entry(struct tree_desc *, struct name_entry *);
void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1);
typedef void (*traverse_callback_t)(int n, unsigned long mask, struct name_entry *entry, const char *base);
void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback);
int get_tree_entry(const unsigned char *, const char *, unsigned char *, unsigned *);
#endif