mirror of
https://github.com/git/git
synced 2024-08-25 02:35:46 +00:00
![Johannes Schindelin](/assets/img/avatar_default.png)
Without this bug fix, t7519's four "status doesn't detect unreported modifications" test cases would fail occasionally (and, oddly enough, *a lot* more frequently on Windows). The reason is that these test cases intentionally use the side effect of `git status` to re-write the index if any updates were detected: they first clean the worktree, run `git status` to update the index as well as show the output to the casual reader, then make the worktree dirty again and expect no changes to reported if running with a mocked fsmonitor hook. The problem with this strategy was that the index was written during said `git status` on the clean worktree for the *wrong* reason: not because the index was marked as changed (it wasn't), but because the recorded mtimes were racy with the index' own mtime. As the mtime granularity on Windows is 100 nanoseconds (see e.g. https://docs.microsoft.com/en-us/windows/desktop/SysInfo/file-times), the mtimes of the files are often enough *not* racy with the index', so that that `git status` call currently does not always update the index (including the fsmonitor extension), causing the test case to fail. The obvious fix: if we change *any* index entry's `CE_FSMONITOR_VALID` flag, we should also mark the index as changed. That will cause the index to be written upon `git status`, *including* an updated fsmonitor extension. Side note: Even though the reader might think that the t7519 issue should be *much* more prevalent on Linux, given that the ext4 filesystem (that seems to be used by every Linux distribution) stores mtimes in nanosecond precision. However, ext4 uses `current_kernel_time()` (see https://unix.stackexchange.com/questions/11599#comment762968_11599; it is *amazingly* hard to find any proper source of information about such ext4 questions) whose accuracy seems to depend on many factors but is safely worse than the 100-nanosecond granularity of NTFS (again, it is *horribly* hard to find anything remotely authoritative about this question). So it seems that the racy index condition that hid the bug fixed by this patch simply is a lot more likely on Linux than on Windows. But not impossible ;-) Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
574 lines
15 KiB
C
574 lines
15 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 "unpack-trees.h"
|
|
#include "refs.h"
|
|
#include "submodule.h"
|
|
#include "dir.h"
|
|
#include "fsmonitor.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;
|
|
}
|
|
|
|
int 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/");
|
|
|
|
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 (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->dense_combined_merges,
|
|
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;
|
|
|
|
/* If CE_VALID is set, don't look at workdir for file removal */
|
|
if (ce->ce_flags & CE_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)) {
|
|
diff_addremove(&revs->diffopt, '+', ce->ce_mode,
|
|
the_hash_algo->empty_tree, 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");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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 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;
|
|
|
|
/*
|
|
* New file in the index: it might actually be different in
|
|
* the working tree.
|
|
*/
|
|
if (get_stat_data(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;
|
|
|
|
if (get_stat_data(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->dense_combined_merges, 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)));
|
|
/*
|
|
* 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".
|
|
*/
|
|
match_missing = !revs->ignore_merges;
|
|
|
|
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) {
|
|
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);
|
|
}
|
|
|
|
int run_diff_index(struct rev_info *revs, int cached)
|
|
{
|
|
struct object_array_entry *ent;
|
|
|
|
if (revs->pending.nr != 1)
|
|
BUG("run_diff_index must be passed exactly one tree");
|
|
|
|
trace_performance_enter();
|
|
ent = revs->pending.objects;
|
|
if (diff_cache(revs, &ent->item->oid, ent->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");
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
revs.diffopt = *opt;
|
|
|
|
if (diff_cache(&revs, tree_oid, NULL, 1))
|
|
exit(128);
|
|
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;
|
|
|
|
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);
|
|
rev.diffopt.ita_invisible_in_index = ita_invisible_in_index;
|
|
run_diff_index(&rev, 1);
|
|
object_array_clear(&rev.pending);
|
|
return (rev.diffopt.flags.has_changes != 0);
|
|
}
|