git/diff-lib.c

796 строки
19 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"
#include "cache-tree.h"
#include "path-list.h"
#include "unpack-trees.h"
/*
* diff-files
*/
static int read_directory(const char *path, struct path_list *list)
{
DIR *dir;
struct dirent *e;
if (!(dir = opendir(path)))
return error("Could not open directory %s", path);
while ((e = readdir(dir)))
if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
path_list_insert(e->d_name, list);
closedir(dir);
return 0;
}
static int get_mode(const char *path, int *mode)
{
struct stat st;
if (!path || !strcmp(path, "/dev/null"))
*mode = 0;
else if (!strcmp(path, "-"))
*mode = create_ce_mode(0666);
else if (stat(path, &st))
return error("Could not access '%s'", path);
else
*mode = st.st_mode;
return 0;
}
static int queue_diff(struct diff_options *o,
const char *name1, const char *name2)
{
int mode1 = 0, mode2 = 0;
if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
return -1;
if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
return error("file/directory conflict: %s, %s", name1, name2);
if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
char buffer1[PATH_MAX], buffer2[PATH_MAX];
struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
int len1 = 0, len2 = 0, i1, i2, ret = 0;
if (name1 && read_directory(name1, &p1))
return -1;
if (name2 && read_directory(name2, &p2)) {
path_list_clear(&p1, 0);
return -1;
}
if (name1) {
len1 = strlen(name1);
if (len1 > 0 && name1[len1 - 1] == '/')
len1--;
memcpy(buffer1, name1, len1);
buffer1[len1++] = '/';
}
if (name2) {
len2 = strlen(name2);
if (len2 > 0 && name2[len2 - 1] == '/')
len2--;
memcpy(buffer2, name2, len2);
buffer2[len2++] = '/';
}
for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
const char *n1, *n2;
int comp;
if (i1 == p1.nr)
comp = 1;
else if (i2 == p2.nr)
comp = -1;
else
comp = strcmp(p1.items[i1].path,
p2.items[i2].path);
if (comp > 0)
n1 = NULL;
else {
n1 = buffer1;
strncpy(buffer1 + len1, p1.items[i1++].path,
PATH_MAX - len1);
}
if (comp < 0)
n2 = NULL;
else {
n2 = buffer2;
strncpy(buffer2 + len2, p2.items[i2++].path,
PATH_MAX - len2);
}
ret = queue_diff(o, n1, n2);
}
path_list_clear(&p1, 0);
path_list_clear(&p2, 0);
return ret;
} else {
struct diff_filespec *d1, *d2;
if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
unsigned tmp;
const char *tmp_c;
tmp = mode1; mode1 = mode2; mode2 = tmp;
tmp_c = name1; name1 = name2; name2 = tmp_c;
}
if (!name1)
name1 = "/dev/null";
if (!name2)
name2 = "/dev/null";
d1 = alloc_filespec(name1);
d2 = alloc_filespec(name2);
fill_filespec(d1, null_sha1, mode1);
fill_filespec(d2, null_sha1, mode2);
diff_queue(&diff_queued_diff, d1, d2);
return 0;
}
}
/*
* Does the path name a blob in the working tree, or a directory
* in the working tree?
*/
static int is_in_index(const char *path)
{
int len, pos;
struct cache_entry *ce;
len = strlen(path);
while (path[len-1] == '/')
len--;
if (!len)
return 1; /* "." */
pos = cache_name_pos(path, len);
if (0 <= pos)
return 1;
pos = -1 - pos;
while (pos < active_nr) {
ce = active_cache[pos++];
if (ce_namelen(ce) <= len ||
strncmp(ce->name, path, len) ||
(ce->name[len] > '/'))
break; /* path cannot be a prefix */
if (ce->name[len] == '/')
return 1;
}
return 0;
}
static int handle_diff_files_args(struct rev_info *revs,
int argc, const char **argv,
unsigned int *options)
{
*options = 0;
/* revs->max_count == -2 means --no-index */
while (1 < argc && argv[1][0] == '-') {
if (!strcmp(argv[1], "--base"))
revs->max_count = 1;
else if (!strcmp(argv[1], "--ours"))
revs->max_count = 2;
else if (!strcmp(argv[1], "--theirs"))
revs->max_count = 3;
else if (!strcmp(argv[1], "-n") ||
!strcmp(argv[1], "--no-index")) {
revs->max_count = -2;
DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
}
else if (!strcmp(argv[1], "-q"))
*options |= DIFF_SILENT_ON_REMOVED;
else
return error("invalid option: %s", argv[1]);
argv++; argc--;
}
if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
/*
* If two files are specified, and at least one is untracked,
* default to no-index.
*/
read_cache();
if (!is_in_index(revs->diffopt.paths[0]) ||
!is_in_index(revs->diffopt.paths[1])) {
revs->max_count = -2;
DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
}
}
/*
* Make sure there are NO revision (i.e. pending object) parameter,
* rev.max_count is reasonable (0 <= n <= 3),
* there is no other revision filtering parameters.
*/
if (revs->pending.nr || revs->max_count > 3 ||
revs->min_age != -1 || revs->max_age != -1)
return error("no revision allowed with diff-files");
if (revs->max_count == -1 &&
(revs->diffopt.output_format & DIFF_FORMAT_PATCH))
revs->combine_merges = revs->dense_combined_merges = 1;
return 0;
}
static int is_outside_repo(const char *path, int nongit, const char *prefix)
{
int i;
if (nongit || !strcmp(path, "-") || is_absolute_path(path))
return 1;
if (prefixcmp(path, "../"))
return 0;
if (!prefix)
return 1;
for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
while (i > 0 && prefix[i - 1] != '/')
i--;
if (--i < 0)
return 1;
path += 3;
}
return 0;
}
int setup_diff_no_index(struct rev_info *revs,
int argc, const char ** argv, int nongit, const char *prefix)
{
int i;
for (i = 1; i < argc; i++)
if (argv[i][0] != '-' || argv[i][1] == '\0')
break;
else if (!strcmp(argv[i], "--")) {
i++;
break;
} else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
i = argc - 3;
DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
break;
}
if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
!is_outside_repo(argv[i], nongit, prefix)))
return -1;
diff_setup(&revs->diffopt);
for (i = 1; i < argc - 2; )
if (!strcmp(argv[i], "--no-index"))
i++;
else {
int j = diff_opt_parse(&revs->diffopt,
argv + i, argc - i);
if (!j)
die("invalid diff option/value: %s", argv[i]);
i += j;
}
if (prefix) {
int len = strlen(prefix);
revs->diffopt.paths = xcalloc(2, sizeof(char*));
for (i = 0; i < 2; i++) {
const char *p = argv[argc - 2 + i];
/*
* stdin should be spelled as '-'; if you have
* path that is '-', spell it as ./-.
*/
p = (strcmp(p, "-")
? xstrdup(prefix_filename(prefix, len, p))
: p);
revs->diffopt.paths[i] = p;
}
}
else
revs->diffopt.paths = argv + argc - 2;
revs->diffopt.nr_paths = 2;
DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
revs->max_count = -2;
if (diff_setup_done(&revs->diffopt) < 0)
die("diff_setup_done failed");
return 0;
}
int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
{
unsigned int options;
if (handle_diff_files_args(revs, argc, argv, &options))
return -1;
if (DIFF_OPT_TST(&revs->diffopt, NO_INDEX)) {
if (revs->diffopt.nr_paths != 2)
return error("need two files/directories with --no-index");
if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
revs->diffopt.paths[1]))
return -1;
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
/*
* The return code for --no-index imitates diff(1):
* 0 = no changes, 1 = changes, else error
*/
return revs->diffopt.found_changes;
}
if (read_cache() < 0) {
perror("read_cache");
return -1;
}
return run_diff_files(revs, options);
}
int run_diff_files(struct rev_info *revs, unsigned int option)
{
int entries, i;
int diff_unmerged_stage = revs->max_count;
int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
? CE_MATCH_RACY_IS_DIRTY : 0);
if (diff_unmerged_stage < 0)
diff_unmerged_stage = 2;
entries = active_nr;
for (i = 0; i < entries; i++) {
struct stat st;
unsigned int oldmode, newmode;
struct cache_entry *ce = active_cache[i];
int changed;
if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
break;
if (!ce_path_match(ce, revs->prune_data))
continue;
if (ce_stage(ce)) {
struct combine_diff_path *dpath;
int num_compare_stages = 0;
size_t path_len;
path_len = ce_namelen(ce);
dpath = xmalloc(combine_diff_path_size(5, path_len));
dpath->path = (char *) &(dpath->parent[5]);
dpath->next = NULL;
dpath->len = path_len;
memcpy(dpath->path, ce->name, path_len);
dpath->path[path_len] = '\0';
hashclr(dpath->sha1);
memset(&(dpath->parent[0]), 0,
sizeof(struct combine_diff_parent)*5);
if (lstat(ce->name, &st) < 0) {
if (errno != ENOENT && errno != ENOTDIR) {
perror(ce->name);
continue;
}
if (silent_on_removed)
continue;
}
else
dpath->mode = ce_mode_from_stat(ce, st.st_mode);
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 = nce->ce_mode;
num_compare_stages++;
hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
dpath->parent[stage-2].mode = ce_mode_from_stat(nce, mode);
dpath->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(dpath, 2,
revs->dense_combined_merges,
revs);
free(dpath);
continue;
}
free(dpath);
dpath = NULL;
/*
* Show the diff for the 'ce' if we found the one
* from the desired stage.
*/
diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
if (ce_stage(ce) != diff_unmerged_stage)
continue;
}
if (ce_uptodate(ce))
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, '-', ce->ce_mode,
ce->sha1, ce->name, NULL);
continue;
}
changed = ce_match_stat(ce, &st, ce_option);
if (!changed && !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
continue;
oldmode = ce->ce_mode;
newmode = ce_mode_from_stat(ce, st.st_mode);
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,
const unsigned char *sha1, unsigned int mode)
{
diff_addremove(&revs->diffopt, prefix[0], mode,
sha1, ce->name, NULL);
}
static int get_stat_data(struct cache_entry *ce,
const unsigned char **sha1p,
unsigned int *modep,
int cached, int match_missing)
{
const unsigned char *sha1 = ce->sha1;
unsigned int mode = ce->ce_mode;
if (!cached) {
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 = ce_mode_from_stat(ce, st.st_mode);
sha1 = null_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)
{
const 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;
const 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;
}
if (revs->combine_merges && !cached &&
(hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
struct combine_diff_path *p;
int pathlen = ce_namelen(new);
p = xmalloc(combine_diff_path_size(2, pathlen));
p->path = (char *) &p->parent[2];
p->next = NULL;
p->len = pathlen;
memcpy(p->path, new->name, pathlen);
p->path[pathlen] = 0;
p->mode = mode;
hashclr(p->sha1);
memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
p->parent[0].status = DIFF_STATUS_MODIFIED;
p->parent[0].mode = new->ce_mode;
hashcpy(p->parent[0].sha1, new->sha1);
p->parent[1].status = DIFF_STATUS_MODIFIED;
p->parent[1].mode = old->ce_mode;
hashcpy(p->parent[1].sha1, old->sha1);
show_combined_diff(p, 2, revs->dense_combined_merges, revs);
free(p);
return 0;
}
oldmode = old->ce_mode;
if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
return 0;
diff_change(&revs->diffopt, oldmode, mode,
old->sha1, sha1, old->name, NULL);
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 |= CE_STAGEMASK;
}
}
/*
* This gets a mix of an existing index and a tree, one pathname entry
* at a time. The index entry may be a single stage-0 one, but it could
* also be multiple unmerged entries (in which case idx_pos/idx_nr will
* give you the position and number of entries in the index).
*/
static void do_oneway_diff(struct unpack_trees_options *o,
struct cache_entry *idx,
struct cache_entry *tree,
int idx_pos, int idx_nr)
{
struct rev_info *revs = o->unpack_data;
int match_missing, cached;
/*
* Backward compatibility wart - "diff-index -m" does
* not mean "do not ignore merges", but "match_missing".
*
* But with the revision flag parsing, that's found in
* "!revs->ignore_merges".
*/
cached = o->index_only;
match_missing = !revs->ignore_merges;
if (cached && idx && ce_stage(idx)) {
if (tree)
diff_unmerge(&revs->diffopt, idx->name, idx->ce_mode, idx->sha1);
return;
}
/*
* Something added to the tree?
*/
if (!tree) {
show_new_file(revs, idx, cached, match_missing);
return;
}
/*
* Something removed from the tree?
*/
if (!idx) {
diff_index_show_file(revs, "-", tree, tree->sha1, tree->ce_mode);
return;
}
/* Show difference between old and new */
show_modified(revs, tree, idx, 1, cached, match_missing);
}
/*
* Count how many index entries go with the first one
*/
static inline int count_skip(const struct cache_entry *src, int pos)
{
int skip = 1;
/* We can only have multiple entries if the first one is not stage-0 */
if (ce_stage(src)) {
struct cache_entry **p = active_cache + pos;
int namelen = ce_namelen(src);
for (;;) {
const struct cache_entry *ce;
pos++;
if (pos >= active_nr)
break;
ce = *++p;
if (ce_namelen(ce) != namelen)
break;
if (memcmp(ce->name, src->name, namelen))
break;
skip++;
}
}
return skip;
}
/*
* The unpack_trees() interface is designed for merging, so
* the different source entries are designed primarily for
* the source trees, with the old index being really mainly
* used for being replaced by the result.
*
* For diffing, the index is more important, and we only have a
* single tree.
*
* We're supposed to return how many index entries we want to skip.
*
* This wrapper makes it all more readable, and takes care of all
* the fairly complex unpack_trees() semantic requirements, including
* the skipping, the path matching, the type conflict cases etc.
*/
static int oneway_diff(struct cache_entry **src,
struct unpack_trees_options *o,
int index_pos)
{
int skip = 0;
struct cache_entry *idx = src[0];
struct cache_entry *tree = src[1];
struct rev_info *revs = o->unpack_data;
if (index_pos >= 0)
skip = count_skip(idx, index_pos);
/*
* Unpack-trees generates a DF/conflict entry if
* there was a directory in the index and a tree
* in the tree. From a diff standpoint, that's a
* delete of the tree and a create of the file.
*/
if (tree == o->df_conflict_entry)
tree = NULL;
if (ce_path_match(idx ? idx : tree, revs->prune_data))
do_oneway_diff(o, idx, tree, index_pos, skip);
return skip;
}
int run_diff_index(struct rev_info *revs, int cached)
{
struct object *ent;
struct tree *tree;
const char *tree_name;
struct unpack_trees_options opts;
struct tree_desc t;
mark_merge_entries();
ent = revs->pending.objects[0].item;
tree_name = revs->pending.objects[0].name;
tree = parse_tree_indirect(ent->sha1);
if (!tree)
return error("bad tree object %s", tree_name);
memset(&opts, 0, sizeof(opts));
opts.head_idx = 1;
opts.index_only = cached;
opts.merge = 1;
opts.fn = oneway_diff;
opts.unpack_data = revs;
init_tree_desc(&t, tree->buffer, tree->size);
if (unpack_trees(1, &t, &opts))
exit(128);
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
return 0;
}
int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
{
struct tree *tree;
struct rev_info revs;
int i;
struct cache_entry **dst;
struct cache_entry *last = NULL;
struct unpack_trees_options opts;
struct tree_desc t;
/*
* This is used by git-blame to run diff-cache internally;
* it potentially needs to repeatedly run this, so we will
* start by removing the higher order entries the last round
* left behind.
*/
dst = active_cache;
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
if (ce_stage(ce)) {
if (last && !strcmp(ce->name, last->name))
continue;
cache_tree_invalidate_path(active_cache_tree,
ce->name);
last = ce;
ce->ce_flags |= CE_REMOVE;
}
*dst++ = ce;
}
active_nr = dst - active_cache;
init_revisions(&revs, NULL);
revs.prune_data = opt->paths;
tree = parse_tree_indirect(tree_sha1);
if (!tree)
die("bad tree object %s", sha1_to_hex(tree_sha1));
memset(&opts, 0, sizeof(opts));
opts.head_idx = 1;
opts.index_only = 1;
opts.merge = 1;
opts.fn = oneway_diff;
opts.unpack_data = &revs;
init_tree_desc(&t, tree->buffer, tree->size);
if (unpack_trees(1, &t, &opts))
exit(128);
return 0;
}