git/diff-lib.c
Junio C Hamano 5c21ac0e7c Libified diff-index: backward compatibility fix.
"diff-index -m" does not mean "do not ignore merges", but means
"pretend missing files match the index".

The previous round tried to address this, but failed because
setup_revisions() ate "-m" flag before the caller had a chance
to intervene.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-04-22 04:03:32 -07:00

345 lines
7.9 KiB
C

/*
* Copyright (C) 2005 Junio C Hamano
*/
#include "cache.h"
#include "quote.h"
#include "commit.h"
#include "diff.h"
#include "diffcore.h"
#include "revision.h"
/*
* diff-files
*/
int run_diff_files(struct rev_info *revs, int silent_on_removed)
{
int entries, i;
int diff_unmerged_stage = revs->max_count;
if (diff_unmerged_stage < 0)
diff_unmerged_stage = 2;
entries = read_cache();
if (entries < 0) {
perror("read_cache");
return -1;
}
for (i = 0; i < entries; i++) {
struct stat st;
unsigned int oldmode, newmode;
struct cache_entry *ce = active_cache[i];
int changed;
if (!ce_path_match(ce, revs->prune_data))
continue;
if (ce_stage(ce)) {
struct {
struct combine_diff_path p;
struct combine_diff_parent filler[5];
} combine;
int num_compare_stages = 0;
combine.p.next = NULL;
combine.p.len = ce_namelen(ce);
combine.p.path = xmalloc(combine.p.len + 1);
memcpy(combine.p.path, ce->name, combine.p.len);
combine.p.path[combine.p.len] = 0;
combine.p.mode = 0;
memset(combine.p.sha1, 0, 20);
memset(&combine.p.parent[0], 0,
sizeof(combine.filler));
while (i < entries) {
struct cache_entry *nce = active_cache[i];
int stage;
if (strcmp(ce->name, nce->name))
break;
/* Stage #2 (ours) is the first parent,
* stage #3 (theirs) is the second.
*/
stage = ce_stage(nce);
if (2 <= stage) {
int mode = ntohl(nce->ce_mode);
num_compare_stages++;
memcpy(combine.p.parent[stage-2].sha1,
nce->sha1, 20);
combine.p.parent[stage-2].mode =
canon_mode(mode);
combine.p.parent[stage-2].status =
DIFF_STATUS_MODIFIED;
}
/* diff against the proper unmerged stage */
if (stage == diff_unmerged_stage)
ce = nce;
i++;
}
/*
* Compensate for loop update
*/
i--;
if (revs->combine_merges && num_compare_stages == 2) {
show_combined_diff(&combine.p, 2,
revs->dense_combined_merges,
revs);
free(combine.p.path);
continue;
}
free(combine.p.path);
/*
* Show the diff for the 'ce' if we found the one
* from the desired stage.
*/
diff_unmerge(&revs->diffopt, ce->name);
if (ce_stage(ce) != diff_unmerged_stage)
continue;
}
if (lstat(ce->name, &st) < 0) {
if (errno != ENOENT && errno != ENOTDIR) {
perror(ce->name);
continue;
}
if (silent_on_removed)
continue;
diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
ce->sha1, ce->name, NULL);
continue;
}
changed = ce_match_stat(ce, &st, 0);
if (!changed && !revs->diffopt.find_copies_harder)
continue;
oldmode = ntohl(ce->ce_mode);
newmode = canon_mode(st.st_mode);
if (!trust_executable_bit &&
S_ISREG(newmode) && S_ISREG(oldmode) &&
((newmode ^ oldmode) == 0111))
newmode = oldmode;
diff_change(&revs->diffopt, oldmode, newmode,
ce->sha1, (changed ? null_sha1 : ce->sha1),
ce->name, NULL);
}
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
return 0;
}
/*
* diff-index
*/
/* A file entry went away or appeared */
static void diff_index_show_file(struct rev_info *revs,
const char *prefix,
struct cache_entry *ce,
unsigned char *sha1, unsigned int mode)
{
diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
sha1, ce->name, NULL);
}
static int get_stat_data(struct cache_entry *ce,
unsigned char **sha1p,
unsigned int *modep,
int cached, int match_missing)
{
unsigned char *sha1 = ce->sha1;
unsigned int mode = ce->ce_mode;
if (!cached) {
static unsigned char no_sha1[20];
int changed;
struct stat st;
if (lstat(ce->name, &st) < 0) {
if (errno == ENOENT && match_missing) {
*sha1p = sha1;
*modep = mode;
return 0;
}
return -1;
}
changed = ce_match_stat(ce, &st, 0);
if (changed) {
mode = create_ce_mode(st.st_mode);
if (!trust_executable_bit && S_ISREG(st.st_mode))
mode = ce->ce_mode;
sha1 = no_sha1;
}
}
*sha1p = sha1;
*modep = mode;
return 0;
}
static void show_new_file(struct rev_info *revs,
struct cache_entry *new,
int cached, int match_missing)
{
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, cached, match_missing) < 0)
return;
diff_index_show_file(revs, "+", new, sha1, mode);
}
static int show_modified(struct rev_info *revs,
struct cache_entry *old,
struct cache_entry *new,
int report_missing,
int cached, int match_missing)
{
unsigned int mode, oldmode;
unsigned char *sha1;
if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
if (report_missing)
diff_index_show_file(revs, "-", old,
old->sha1, old->ce_mode);
return -1;
}
oldmode = old->ce_mode;
if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
!revs->diffopt.find_copies_harder)
return 0;
mode = ntohl(mode);
oldmode = ntohl(oldmode);
diff_change(&revs->diffopt, oldmode, mode,
old->sha1, sha1, old->name, NULL);
return 0;
}
static int diff_cache(struct rev_info *revs,
struct cache_entry **ac, int entries,
const char **pathspec,
int cached, int match_missing)
{
while (entries) {
struct cache_entry *ce = *ac;
int same = (entries > 1) && ce_same_name(ce, ac[1]);
if (!ce_path_match(ce, pathspec))
goto skip_entry;
switch (ce_stage(ce)) {
case 0:
/* No stage 1 entry? That means it's a new file */
if (!same) {
show_new_file(revs, ce, cached, match_missing);
break;
}
/* Show difference between old and new */
show_modified(revs,ac[1], ce, 1,
cached, match_missing);
break;
case 1:
/* No stage 3 (merge) entry?
* That means it's been deleted.
*/
if (!same) {
diff_index_show_file(revs, "-", ce,
ce->sha1, ce->ce_mode);
break;
}
/* We come here with ce pointing at stage 1
* (original tree) and ac[1] pointing at stage
* 3 (unmerged). show-modified with
* report-missing set to false does not say the
* file is deleted but reports true if work
* tree does not have it, in which case we
* fall through to report the unmerged state.
* Otherwise, we show the differences between
* the original tree and the work tree.
*/
if (!cached &&
!show_modified(revs, ce, ac[1], 0,
cached, match_missing))
break;
/* fallthru */
case 3:
diff_unmerge(&revs->diffopt, ce->name);
break;
default:
die("impossible cache entry stage");
}
skip_entry:
/*
* Ignore all the different stages for this file,
* we've handled the relevant cases now.
*/
do {
ac++;
entries--;
} while (entries && ce_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);
}
}
int run_diff_index(struct rev_info *revs, int cached)
{
int ret;
struct object *ent;
struct tree *tree;
const char *tree_name;
int match_missing = 0;
/*
* Backward compatibility wart - "diff-index -m" does
* not mean "do not ignore merges", but totally different.
*/
if (!revs->ignore_merges)
match_missing = 1;
if (read_cache() < 0) {
perror("read_cache");
return -1;
}
mark_merge_entries();
ent = revs->pending_objects->item;
tree_name = revs->pending_objects->name;
tree = parse_tree_indirect(ent->sha1);
if (!tree)
return error("bad tree object %s", tree_name);
if (read_tree(tree, 1, revs->prune_data))
return error("unable to read tree object %s", tree_name);
ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
cached, match_missing);
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
return ret;
}