git/diff-lib.c
Junio C Hamano 671eaaac0c Merge branch 'js/diff-cached-fsmonitor-fix'
"git diff --cached" codepath did not fill the necessary stat
information for a file when fsmonitor knows it is clean and ended
up behaving as if it is not clean, which has been corrected.

* js/diff-cached-fsmonitor-fix:
  diff-lib: fix check_removed when fsmonitor is on
2023-09-20 10:44:57 -07:00

713 lines
19 KiB
C

/*
* Copyright (C) 2005 Junio C Hamano
*/
#include "git-compat-util.h"
#include "quote.h"
#include "commit.h"
#include "diff.h"
#include "diffcore.h"
#include "gettext.h"
#include "hash.h"
#include "hex.h"
#include "object-name.h"
#include "read-cache.h"
#include "revision.h"
#include "cache-tree.h"
#include "unpack-trees.h"
#include "refs.h"
#include "repository.h"
#include "submodule.h"
#include "symlinks.h"
#include "trace.h"
#include "dir.h"
#include "fsmonitor.h"
#include "commit-reach.h"
/*
* diff-files
*/
/*
* Has the work tree entity been removed?
*
* Return 1 if it was removed from the work tree, 0 if an entity to be
* compared with the cache entry ce still exists (the latter includes
* the case where a directory that is not a submodule repository
* exists for ce that is a submodule -- it is a submodule that is not
* checked out). Return negative for an error.
*/
static int check_removed(const struct cache_entry *ce, struct stat *st)
{
if (lstat(ce->name, st) < 0) {
if (!is_missing_file_error(errno))
return -1;
return 1;
}
if (has_symlink_leading_path(ce->name, ce_namelen(ce)))
return 1;
if (S_ISDIR(st->st_mode)) {
struct object_id sub;
/*
* If ce is already a gitlink, we can have a plain
* directory (i.e. the submodule is not checked out),
* or a checked out submodule. Either case this is not
* a case where something was removed from the work tree,
* so we will return 0.
*
* Otherwise, if the directory is not a submodule
* repository, that means ce which was a blob turned into
* a directory --- the blob was removed!
*/
if (!S_ISGITLINK(ce->ce_mode) &&
resolve_gitlink_ref(ce->name, "HEAD", &sub))
return 1;
}
return 0;
}
/*
* Has a file changed or has a submodule new commits or a dirty work tree?
*
* Return 1 when changes are detected, 0 otherwise. If the DIRTY_SUBMODULES
* option is set, the caller does not only want to know if a submodule is
* modified at all but wants to know all the conditions that are met (new
* commits, untracked content and/or modified content).
*/
static int match_stat_with_submodule(struct diff_options *diffopt,
const struct cache_entry *ce,
struct stat *st, unsigned ce_option,
unsigned *dirty_submodule)
{
int changed = ie_match_stat(diffopt->repo->index, ce, st, ce_option);
if (S_ISGITLINK(ce->ce_mode)) {
struct diff_flags orig_flags = diffopt->flags;
if (!diffopt->flags.override_submodule_config)
set_diffopt_flags_from_submodule_config(diffopt, ce->name);
if (diffopt->flags.ignore_submodules)
changed = 0;
else if (!diffopt->flags.ignore_dirty_submodules &&
(!changed || diffopt->flags.dirty_submodules))
*dirty_submodule = is_submodule_modified(ce->name,
diffopt->flags.ignore_untracked_in_submodules);
diffopt->flags = orig_flags;
}
return changed;
}
void run_diff_files(struct rev_info *revs, unsigned int option)
{
int entries, i;
int diff_unmerged_stage = revs->max_count;
unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
? CE_MATCH_RACY_IS_DIRTY : 0);
uint64_t start = getnanotime();
struct index_state *istate = revs->diffopt.repo->index;
diff_set_mnemonic_prefix(&revs->diffopt, "i/", "w/");
refresh_fsmonitor(istate);
if (diff_unmerged_stage < 0)
diff_unmerged_stage = 2;
entries = istate->cache_nr;
for (i = 0; i < entries; i++) {
unsigned int oldmode, newmode;
struct cache_entry *ce = istate->cache[i];
int changed;
unsigned dirty_submodule = 0;
const struct object_id *old_oid, *new_oid;
if (diff_can_quit_early(&revs->diffopt))
break;
if (!ce_path_match(istate, ce, &revs->prune_data, NULL))
continue;
if (revs->diffopt.prefix &&
strncmp(ce->name, revs->diffopt.prefix, revs->diffopt.prefix_length))
continue;
if (ce_stage(ce)) {
struct combine_diff_path *dpath;
struct diff_filepair *pair;
unsigned int wt_mode = 0;
int num_compare_stages = 0;
size_t path_len;
struct stat st;
path_len = ce_namelen(ce);
dpath = xmalloc(combine_diff_path_size(5, path_len));
dpath->path = (char *) &(dpath->parent[5]);
dpath->next = NULL;
memcpy(dpath->path, ce->name, path_len);
dpath->path[path_len] = '\0';
oidclr(&dpath->oid);
memset(&(dpath->parent[0]), 0,
sizeof(struct combine_diff_parent)*5);
changed = check_removed(ce, &st);
if (!changed)
wt_mode = ce_mode_from_stat(ce, st.st_mode);
else {
if (changed < 0) {
perror(ce->name);
continue;
}
wt_mode = 0;
}
dpath->mode = wt_mode;
while (i < entries) {
struct cache_entry *nce = istate->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++;
oidcpy(&dpath->parent[stage - 2].oid,
&nce->oid);
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);
free(dpath);
continue;
}
FREE_AND_NULL(dpath);
/*
* Show the diff for the 'ce' if we found the one
* from the desired stage.
*/
pair = diff_unmerge(&revs->diffopt, ce->name);
if (wt_mode)
pair->two->mode = wt_mode;
if (ce_stage(ce) != diff_unmerged_stage)
continue;
}
if (ce_uptodate(ce) || ce_skip_worktree(ce))
continue;
/*
* When CE_VALID is set (via "update-index --assume-unchanged"
* or via adding paths while core.ignorestat is set to true),
* the user has promised that the working tree file for that
* path will not be modified. When CE_FSMONITOR_VALID is true,
* the fsmonitor knows that the path hasn't been modified since
* we refreshed the cached stat information. In either case,
* we do not have to stat to see if the path has been removed
* or modified.
*/
if (ce->ce_flags & (CE_VALID | CE_FSMONITOR_VALID)) {
changed = 0;
newmode = ce->ce_mode;
} else {
struct stat st;
changed = check_removed(ce, &st);
if (changed) {
if (changed < 0) {
perror(ce->name);
continue;
}
diff_addremove(&revs->diffopt, '-', ce->ce_mode,
&ce->oid,
!is_null_oid(&ce->oid),
ce->name, 0);
continue;
} else if (revs->diffopt.ita_invisible_in_index &&
ce_intent_to_add(ce)) {
newmode = ce_mode_from_stat(ce, st.st_mode);
diff_addremove(&revs->diffopt, '+', newmode,
null_oid(), 0, ce->name, 0);
continue;
}
changed = match_stat_with_submodule(&revs->diffopt, ce, &st,
ce_option, &dirty_submodule);
newmode = ce_mode_from_stat(ce, st.st_mode);
}
if (!changed && !dirty_submodule) {
ce_mark_uptodate(ce);
mark_fsmonitor_valid(istate, ce);
if (!revs->diffopt.flags.find_copies_harder)
continue;
}
oldmode = ce->ce_mode;
old_oid = &ce->oid;
new_oid = changed ? null_oid() : &ce->oid;
diff_change(&revs->diffopt, oldmode, newmode,
old_oid, new_oid,
!is_null_oid(old_oid),
!is_null_oid(new_oid),
ce->name, 0, dirty_submodule);
}
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
trace_performance_since(start, "diff-files");
}
/*
* diff-index
*/
/* A file entry went away or appeared */
static void diff_index_show_file(struct rev_info *revs,
const char *prefix,
const struct cache_entry *ce,
const struct object_id *oid, int oid_valid,
unsigned int mode,
unsigned dirty_submodule)
{
diff_addremove(&revs->diffopt, prefix[0], mode,
oid, oid_valid, ce->name, dirty_submodule);
}
static int get_stat_data(const struct index_state *istate,
const struct cache_entry *ce,
const struct object_id **oidp,
unsigned int *modep,
int cached, int match_missing,
unsigned *dirty_submodule, struct diff_options *diffopt)
{
const struct object_id *oid = &ce->oid;
unsigned int mode = ce->ce_mode;
if (!cached && !ce_uptodate(ce)) {
int changed;
struct stat st;
changed = check_removed(ce, &st);
if (changed < 0)
return -1;
else if (changed) {
if (match_missing) {
*oidp = oid;
*modep = mode;
return 0;
}
return -1;
}
changed = match_stat_with_submodule(diffopt, ce, &st,
0, dirty_submodule);
if (changed) {
mode = ce_mode_from_stat(ce, st.st_mode);
oid = null_oid();
}
}
*oidp = oid;
*modep = mode;
return 0;
}
static void show_new_file(struct rev_info *revs,
const struct cache_entry *new_file,
int cached, int match_missing)
{
const struct object_id *oid;
unsigned int mode;
unsigned dirty_submodule = 0;
struct index_state *istate = revs->diffopt.repo->index;
if (new_file && S_ISSPARSEDIR(new_file->ce_mode)) {
diff_tree_oid(NULL, &new_file->oid, new_file->name, &revs->diffopt);
return;
}
/*
* New file in the index: it might actually be different in
* the working tree.
*/
if (get_stat_data(istate, new_file, &oid, &mode, cached, match_missing,
&dirty_submodule, &revs->diffopt) < 0)
return;
diff_index_show_file(revs, "+", new_file, oid, !is_null_oid(oid), mode, dirty_submodule);
}
static int show_modified(struct rev_info *revs,
const struct cache_entry *old_entry,
const struct cache_entry *new_entry,
int report_missing,
int cached, int match_missing)
{
unsigned int mode, oldmode;
const struct object_id *oid;
unsigned dirty_submodule = 0;
struct index_state *istate = revs->diffopt.repo->index;
assert(S_ISSPARSEDIR(old_entry->ce_mode) ==
S_ISSPARSEDIR(new_entry->ce_mode));
/*
* If both are sparse directory entries, then expand the
* modifications to the file level. If only one was a sparse
* directory, then they appear as an add and delete instead of
* a modification.
*/
if (S_ISSPARSEDIR(new_entry->ce_mode)) {
diff_tree_oid(&old_entry->oid, &new_entry->oid, new_entry->name, &revs->diffopt);
return 0;
}
if (get_stat_data(istate, new_entry, &oid, &mode, cached, match_missing,
&dirty_submodule, &revs->diffopt) < 0) {
if (report_missing)
diff_index_show_file(revs, "-", old_entry,
&old_entry->oid, 1, old_entry->ce_mode,
0);
return -1;
}
if (revs->combine_merges && !cached &&
(!oideq(oid, &old_entry->oid) || !oideq(&old_entry->oid, &new_entry->oid))) {
struct combine_diff_path *p;
int pathlen = ce_namelen(new_entry);
p = xmalloc(combine_diff_path_size(2, pathlen));
p->path = (char *) &p->parent[2];
p->next = NULL;
memcpy(p->path, new_entry->name, pathlen);
p->path[pathlen] = 0;
p->mode = mode;
oidclr(&p->oid);
memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
p->parent[0].status = DIFF_STATUS_MODIFIED;
p->parent[0].mode = new_entry->ce_mode;
oidcpy(&p->parent[0].oid, &new_entry->oid);
p->parent[1].status = DIFF_STATUS_MODIFIED;
p->parent[1].mode = old_entry->ce_mode;
oidcpy(&p->parent[1].oid, &old_entry->oid);
show_combined_diff(p, 2, revs);
free(p);
return 0;
}
oldmode = old_entry->ce_mode;
if (mode == oldmode && oideq(oid, &old_entry->oid) && !dirty_submodule &&
!revs->diffopt.flags.find_copies_harder)
return 0;
diff_change(&revs->diffopt, oldmode, mode,
&old_entry->oid, oid, 1, !is_null_oid(oid),
old_entry->name, 0, dirty_submodule);
return 0;
}
/*
* 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,
const struct cache_entry *idx,
const struct cache_entry *tree)
{
struct rev_info *revs = o->unpack_data;
int match_missing, cached;
/*
* i-t-a entries do not actually exist in the index (if we're
* looking at its content)
*/
if (o->index_only &&
revs->diffopt.ita_invisible_in_index &&
idx && ce_intent_to_add(idx)) {
idx = NULL;
if (!tree)
return; /* nothing to diff.. */
}
/* if the entry is not checked out, don't examine work tree */
cached = o->index_only ||
(idx && ((idx->ce_flags & CE_VALID) || ce_skip_worktree(idx)));
match_missing = revs->match_missing;
if (cached && idx && ce_stage(idx)) {
struct diff_filepair *pair;
pair = diff_unmerge(&revs->diffopt, idx->name);
if (tree)
fill_filespec(pair->one, &tree->oid, 1,
tree->ce_mode);
return;
}
/*
* Something added to the tree?
*/
if (!tree) {
show_new_file(revs, idx, cached, match_missing);
return;
}
/*
* Something removed from the tree?
*/
if (!idx) {
if (S_ISSPARSEDIR(tree->ce_mode)) {
diff_tree_oid(&tree->oid, NULL, tree->name, &revs->diffopt);
return;
}
diff_index_show_file(revs, "-", tree, &tree->oid, 1,
tree->ce_mode, 0);
return;
}
/* Show difference between old and new */
show_modified(revs, tree, idx, 1, cached, match_missing);
}
/*
* 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 advance o->pos to skip what we have already processed.
*
* 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(const struct cache_entry * const *src,
struct unpack_trees_options *o)
{
const struct cache_entry *idx = src[0];
const struct cache_entry *tree = src[1];
struct rev_info *revs = o->unpack_data;
/*
* 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(revs->diffopt.repo->index,
idx ? idx : tree,
&revs->prune_data, NULL)) {
do_oneway_diff(o, idx, tree);
if (diff_can_quit_early(&revs->diffopt)) {
o->exiting_early = 1;
return -1;
}
}
return 0;
}
static int diff_cache(struct rev_info *revs,
const struct object_id *tree_oid,
const char *tree_name,
int cached)
{
struct tree *tree;
struct tree_desc t;
struct unpack_trees_options opts;
tree = parse_tree_indirect(tree_oid);
if (!tree)
return error("bad tree object %s",
tree_name ? tree_name : oid_to_hex(tree_oid));
memset(&opts, 0, sizeof(opts));
opts.head_idx = 1;
opts.index_only = cached;
opts.diff_index_cached = (cached &&
!revs->diffopt.flags.find_copies_harder);
opts.merge = 1;
opts.fn = oneway_diff;
opts.unpack_data = revs;
opts.src_index = revs->diffopt.repo->index;
opts.dst_index = NULL;
opts.pathspec = &revs->diffopt.pathspec;
opts.pathspec->recursive = 1;
init_tree_desc(&t, tree->buffer, tree->size);
return unpack_trees(1, &t, &opts);
}
void diff_get_merge_base(const struct rev_info *revs, struct object_id *mb)
{
int i;
struct commit *mb_child[2] = {0};
struct commit_list *merge_bases;
for (i = 0; i < revs->pending.nr; i++) {
struct object *obj = revs->pending.objects[i].item;
if (obj->flags)
die(_("--merge-base does not work with ranges"));
if (obj->type != OBJ_COMMIT)
die(_("--merge-base only works with commits"));
}
/*
* This check must go after the for loop above because A...B
* ranges produce three pending commits, resulting in a
* misleading error message.
*/
if (revs->pending.nr < 1 || revs->pending.nr > 2)
BUG("unexpected revs->pending.nr: %d", revs->pending.nr);
for (i = 0; i < revs->pending.nr; i++)
mb_child[i] = lookup_commit_reference(the_repository, &revs->pending.objects[i].item->oid);
if (revs->pending.nr == 1) {
struct object_id oid;
if (repo_get_oid(the_repository, "HEAD", &oid))
die(_("unable to get HEAD"));
mb_child[1] = lookup_commit_reference(the_repository, &oid);
}
merge_bases = repo_get_merge_bases(the_repository, mb_child[0], mb_child[1]);
if (!merge_bases)
die(_("no merge base found"));
if (merge_bases->next)
die(_("multiple merge bases found"));
oidcpy(mb, &merge_bases->item->object.oid);
free_commit_list(merge_bases);
}
void run_diff_index(struct rev_info *revs, unsigned int option)
{
struct object_array_entry *ent;
int cached = !!(option & DIFF_INDEX_CACHED);
int merge_base = !!(option & DIFF_INDEX_MERGE_BASE);
struct object_id oid;
const char *name;
char merge_base_hex[GIT_MAX_HEXSZ + 1];
struct index_state *istate = revs->diffopt.repo->index;
if (revs->pending.nr != 1)
BUG("run_diff_index must be passed exactly one tree");
trace_performance_enter();
ent = revs->pending.objects;
refresh_fsmonitor(istate);
if (merge_base) {
diff_get_merge_base(revs, &oid);
name = oid_to_hex_r(merge_base_hex, &oid);
} else {
oidcpy(&oid, &ent->item->oid);
name = ent->name;
}
if (diff_cache(revs, &oid, name, cached))
exit(128);
diff_set_mnemonic_prefix(&revs->diffopt, "c/", cached ? "i/" : "w/");
diffcore_fix_diff_index();
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
trace_performance_leave("diff-index");
}
int do_diff_cache(const struct object_id *tree_oid, struct diff_options *opt)
{
struct rev_info revs;
repo_init_revisions(opt->repo, &revs, NULL);
copy_pathspec(&revs.prune_data, &opt->pathspec);
diff_setup_done(&revs.diffopt);
revs.diffopt = *opt;
if (diff_cache(&revs, tree_oid, NULL, 1))
exit(128);
release_revisions(&revs);
return 0;
}
int index_differs_from(struct repository *r,
const char *def, const struct diff_flags *flags,
int ita_invisible_in_index)
{
struct rev_info rev;
struct setup_revision_opt opt;
unsigned has_changes;
repo_init_revisions(r, &rev, NULL);
memset(&opt, 0, sizeof(opt));
opt.def = def;
setup_revisions(0, NULL, &rev, &opt);
rev.diffopt.flags.quick = 1;
rev.diffopt.flags.exit_with_status = 1;
if (flags) {
diff_flags_or(&rev.diffopt.flags, flags);
/*
* Now that flags are merged, honor override_submodule_config
* and ignore_submodules from passed flags.
*/
if (flags->override_submodule_config)
rev.diffopt.flags.ignore_submodules = flags->ignore_submodules;
}
rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
run_diff_index(&rev, DIFF_INDEX_CACHED);
has_changes = rev.diffopt.flags.has_changes;
release_revisions(&rev);
return (has_changes != 0);
}
static struct strbuf *idiff_prefix_cb(struct diff_options *opt UNUSED, void *data)
{
return data;
}
void show_interdiff(const struct object_id *oid1, const struct object_id *oid2,
int indent, struct diff_options *diffopt)
{
struct diff_options opts;
struct strbuf prefix = STRBUF_INIT;
memcpy(&opts, diffopt, sizeof(opts));
opts.output_format = DIFF_FORMAT_PATCH;
opts.output_prefix = idiff_prefix_cb;
strbuf_addchars(&prefix, ' ', indent);
opts.output_prefix_data = &prefix;
diff_setup_done(&opts);
diff_tree_oid(oid1, oid2, "", &opts);
diffcore_std(&opts);
diff_flush(&opts);
strbuf_release(&prefix);
}