git/diff-cache.c
Junio C Hamano 40469ee9c6 [PATCH] Rename and extend read_tree_with_tree_or_commit_sha1
This patch renames read_tree_with_tree_or_commit_sha1() to
read_object_with_reference() and extends it to automatically
dereference not just "commit" objects but "tag" objects.  With
this patch, you can say e.g.:

    ls-tree $tag
    read-tree -m $(merge-base $tag $HEAD) $tag $HEAD
    diff-cache $tag
    diff-tree $tag $HEAD

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-28 16:42:27 -07:00

191 lines
4.2 KiB
C

#include "cache.h"
#include "diff.h"
static int cached_only = 0;
static int generate_patch = 0;
static int line_termination = '\n';
/* A file entry went away or appeared */
static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
{
if (generate_patch)
diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
else
printf("%s%06o\tblob\t%s\t%s%c", prefix, ntohl(mode),
sha1_to_hex(sha1), ce->name, line_termination);
}
static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
{
unsigned char *sha1 = ce->sha1;
unsigned int mode = ce->ce_mode;
if (!cached_only) {
static unsigned char no_sha1[20];
int changed;
struct stat st;
if (stat(ce->name, &st) < 0)
return -1;
changed = cache_match_stat(ce, &st);
if (changed) {
mode = create_ce_mode(st.st_mode);
sha1 = no_sha1;
}
}
*sha1p = sha1;
*modep = mode;
return 0;
}
static void show_new_file(struct cache_entry *new)
{
unsigned char *sha1;
unsigned int mode;
/* New file in the index: it might actually be different in the working copy */
if (get_stat_data(new, &sha1, &mode) < 0)
return;
show_file("+", new, sha1, mode);
}
static int show_modified(struct cache_entry *old, struct cache_entry *new)
{
unsigned int mode, oldmode;
unsigned char *sha1;
unsigned char old_sha1_hex[60];
if (get_stat_data(new, &sha1, &mode) < 0) {
show_file("-", old, old->sha1, old->ce_mode);
return -1;
}
oldmode = old->ce_mode;
if (mode == oldmode && !memcmp(sha1, old->sha1, 20))
return 0;
mode = ntohl(mode);
oldmode = ntohl(oldmode);
if (generate_patch)
diff_change(oldmode, mode,
old->sha1, sha1, old->name, NULL);
else {
strcpy(old_sha1_hex, sha1_to_hex(old->sha1));
printf("*%06o->%06o\tblob\t%s->%s\t%s%c", oldmode, mode,
old_sha1_hex, sha1_to_hex(sha1),
old->name, line_termination);
}
return 0;
}
static int diff_cache(struct cache_entry **ac, int entries)
{
while (entries) {
struct cache_entry *ce = *ac;
int same = (entries > 1) && same_name(ce, ac[1]);
switch (ce_stage(ce)) {
case 0:
/* No stage 1 entry? That means it's a new file */
if (!same) {
show_new_file(ce);
break;
}
/* Show difference between old and new */
show_modified(ac[1], ce);
break;
case 1:
/* No stage 3 (merge) entry? That means it's been deleted */
if (!same) {
show_file("-", ce, ce->sha1, ce->ce_mode);
break;
}
/* Otherwise we fall through to the "unmerged" case */
case 3:
if (generate_patch)
diff_unmerge(ce->name);
else
printf("U %s%c", ce->name, line_termination);
break;
default:
die("impossible cache entry stage");
}
/*
* Ignore all the different stages for this file,
* we've handled the relevant cases now.
*/
do {
ac++;
entries--;
} while (entries && same_name(ce, ac[0]));
}
return 0;
}
/*
* This turns all merge entries into "stage 3". That guarantees that
* when we read in the new tree (into "stage 1"), we won't lose sight
* of the fact that we had unmerged entries.
*/
static void mark_merge_entries(void)
{
int i;
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
if (!ce_stage(ce))
continue;
ce->ce_flags |= htons(CE_STAGEMASK);
}
}
static char *diff_cache_usage =
"diff-cache [-r] [-z] [-p] [--cached] <tree sha1>";
int main(int argc, char **argv)
{
unsigned char tree_sha1[20];
void *tree;
unsigned long size;
read_cache();
while (argc > 2) {
char *arg = argv[1];
argv++;
argc--;
if (!strcmp(arg, "-r")) {
/* We accept the -r flag just to look like diff-tree */
continue;
}
if (!strcmp(arg, "-p")) {
generate_patch = 1;
continue;
}
if (!strcmp(arg, "-z")) {
line_termination = '\0';
continue;
}
if (!strcmp(arg, "--cached")) {
cached_only = 1;
continue;
}
usage(diff_cache_usage);
}
if (argc != 2 || get_sha1_hex(argv[1], tree_sha1))
usage(diff_cache_usage);
mark_merge_entries();
tree = read_object_with_reference(tree_sha1, "tree", &size, 0);
if (!tree)
die("bad tree object %s", argv[1]);
if (read_tree(tree, size, 1))
die("unable to read tree object %s", argv[1]);
return diff_cache(active_cache, active_nr);
}