git/worktree.c
Ævar Arnfjörð Bjarmason ce14de03db refs API: remove "failure_errno" from refs_resolve_ref_unsafe()
Remove the now-unused "failure_errno" parameter from the
refs_resolve_ref_unsafe() signature. In my recent 96f6623ada (Merge
branch 'ab/refs-errno-cleanup', 2021-11-29) series we made all of its
callers explicitly request the errno via an output parameter.

As that series shows all but one caller ended up passing in a
boilerplate "ignore_errno", since they only cared about whether the
return value was NULL or not, i.e. if the ref could be resolved.

There was one small issue with that series fixed with a follow-up in
31e3912369 (Merge branch 'ab/refs-errno-cleanup', 2022-01-14) a small
bug in that series was fixed.

After those two there was one caller left in sequencer.c that used the
"failure_errno', but as of the preceding commit it uses a boilerplate
"ignore_errno" instead.

This leaves the public refs API without any use of "failure_errno" at
all. We could still do with a bit of cleanup and generalization
between refs.c and refs/files-backend.c before the "reftable"
integration lands, but that's all internal to the reference code
itself.

So let's remove this output parameter. Not only isn't it used now, but
it's unlikely that we'll want it again in the future. We'd like to
slowly move the refs API to a more file-backend independent way of
communicating error codes, having it use a "failure_errno" was only
the first step in that direction. If this or any other function needs
to communicate what specifically is wrong with the requested "refname"
it'll be better to have the function set some output enum of
well-defined error states than piggy-backend on "errno".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-26 15:58:41 -08:00

823 lines
20 KiB
C

#include "cache.h"
#include "repository.h"
#include "refs.h"
#include "strbuf.h"
#include "worktree.h"
#include "dir.h"
#include "wt-status.h"
void free_worktrees(struct worktree **worktrees)
{
int i = 0;
for (i = 0; worktrees[i]; i++) {
free(worktrees[i]->path);
free(worktrees[i]->id);
free(worktrees[i]->head_ref);
free(worktrees[i]->lock_reason);
free(worktrees[i]->prune_reason);
free(worktrees[i]);
}
free (worktrees);
}
/**
* Update head_oid, head_ref and is_detached of the given worktree
*/
static void add_head_info(struct worktree *wt)
{
int flags;
const char *target;
target = refs_resolve_ref_unsafe(get_worktree_ref_store(wt),
"HEAD",
0,
&wt->head_oid, &flags);
if (!target)
return;
if (flags & REF_ISSYMREF)
wt->head_ref = xstrdup(target);
else
wt->is_detached = 1;
}
/**
* get the main worktree
*/
static struct worktree *get_main_worktree(void)
{
struct worktree *worktree = NULL;
struct strbuf worktree_path = STRBUF_INIT;
strbuf_add_real_path(&worktree_path, get_git_common_dir());
strbuf_strip_suffix(&worktree_path, "/.git");
CALLOC_ARRAY(worktree, 1);
worktree->path = strbuf_detach(&worktree_path, NULL);
/*
* NEEDSWORK: If this function is called from a secondary worktree and
* config.worktree is present, is_bare_repository_cfg will reflect the
* contents of config.worktree, not the contents of the main worktree.
* This means that worktree->is_bare may be set to 0 even if the main
* worktree is configured to be bare.
*/
worktree->is_bare = (is_bare_repository_cfg == 1) ||
is_bare_repository();
add_head_info(worktree);
return worktree;
}
static struct worktree *get_linked_worktree(const char *id)
{
struct worktree *worktree = NULL;
struct strbuf path = STRBUF_INIT;
struct strbuf worktree_path = STRBUF_INIT;
if (!id)
die("Missing linked worktree name");
strbuf_git_common_path(&path, the_repository, "worktrees/%s/gitdir", id);
if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
/* invalid gitdir file */
goto done;
strbuf_rtrim(&worktree_path);
strbuf_strip_suffix(&worktree_path, "/.git");
CALLOC_ARRAY(worktree, 1);
worktree->path = strbuf_detach(&worktree_path, NULL);
worktree->id = xstrdup(id);
add_head_info(worktree);
done:
strbuf_release(&path);
strbuf_release(&worktree_path);
return worktree;
}
static void mark_current_worktree(struct worktree **worktrees)
{
char *git_dir = absolute_pathdup(get_git_dir());
int i;
for (i = 0; worktrees[i]; i++) {
struct worktree *wt = worktrees[i];
const char *wt_git_dir = get_worktree_git_dir(wt);
if (!fspathcmp(git_dir, absolute_path(wt_git_dir))) {
wt->is_current = 1;
break;
}
}
free(git_dir);
}
struct worktree **get_worktrees(void)
{
struct worktree **list = NULL;
struct strbuf path = STRBUF_INIT;
DIR *dir;
struct dirent *d;
int counter = 0, alloc = 2;
ALLOC_ARRAY(list, alloc);
list[counter++] = get_main_worktree();
strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
dir = opendir(path.buf);
strbuf_release(&path);
if (dir) {
while ((d = readdir_skip_dot_and_dotdot(dir)) != NULL) {
struct worktree *linked = NULL;
if ((linked = get_linked_worktree(d->d_name))) {
ALLOC_GROW(list, counter + 1, alloc);
list[counter++] = linked;
}
}
closedir(dir);
}
ALLOC_GROW(list, counter + 1, alloc);
list[counter] = NULL;
mark_current_worktree(list);
return list;
}
const char *get_worktree_git_dir(const struct worktree *wt)
{
if (!wt)
return get_git_dir();
else if (!wt->id)
return get_git_common_dir();
else
return git_common_path("worktrees/%s", wt->id);
}
static struct worktree *find_worktree_by_suffix(struct worktree **list,
const char *suffix)
{
struct worktree *found = NULL;
int nr_found = 0, suffixlen;
suffixlen = strlen(suffix);
if (!suffixlen)
return NULL;
for (; *list && nr_found < 2; list++) {
const char *path = (*list)->path;
int pathlen = strlen(path);
int start = pathlen - suffixlen;
/* suffix must start at directory boundary */
if ((!start || (start > 0 && is_dir_sep(path[start - 1]))) &&
!fspathcmp(suffix, path + start)) {
found = *list;
nr_found++;
}
}
return nr_found == 1 ? found : NULL;
}
struct worktree *find_worktree(struct worktree **list,
const char *prefix,
const char *arg)
{
struct worktree *wt;
char *to_free = NULL;
if ((wt = find_worktree_by_suffix(list, arg)))
return wt;
if (prefix)
arg = to_free = prefix_filename(prefix, arg);
wt = find_worktree_by_path(list, arg);
free(to_free);
return wt;
}
struct worktree *find_worktree_by_path(struct worktree **list, const char *p)
{
struct strbuf wt_path = STRBUF_INIT;
char *path = real_pathdup(p, 0);
if (!path)
return NULL;
for (; *list; list++) {
if (!strbuf_realpath(&wt_path, (*list)->path, 0))
continue;
if (!fspathcmp(path, wt_path.buf))
break;
}
free(path);
strbuf_release(&wt_path);
return *list;
}
int is_main_worktree(const struct worktree *wt)
{
return !wt->id;
}
const char *worktree_lock_reason(struct worktree *wt)
{
if (is_main_worktree(wt))
return NULL;
if (!wt->lock_reason_valid) {
struct strbuf path = STRBUF_INIT;
strbuf_addstr(&path, worktree_git_path(wt, "locked"));
if (file_exists(path.buf)) {
struct strbuf lock_reason = STRBUF_INIT;
if (strbuf_read_file(&lock_reason, path.buf, 0) < 0)
die_errno(_("failed to read '%s'"), path.buf);
strbuf_trim(&lock_reason);
wt->lock_reason = strbuf_detach(&lock_reason, NULL);
} else
wt->lock_reason = NULL;
wt->lock_reason_valid = 1;
strbuf_release(&path);
}
return wt->lock_reason;
}
const char *worktree_prune_reason(struct worktree *wt, timestamp_t expire)
{
struct strbuf reason = STRBUF_INIT;
char *path = NULL;
if (is_main_worktree(wt))
return NULL;
if (wt->prune_reason_valid)
return wt->prune_reason;
if (should_prune_worktree(wt->id, &reason, &path, expire))
wt->prune_reason = strbuf_detach(&reason, NULL);
wt->prune_reason_valid = 1;
strbuf_release(&reason);
free(path);
return wt->prune_reason;
}
/* convenient wrapper to deal with NULL strbuf */
__attribute__((format (printf, 2, 3)))
static void strbuf_addf_gently(struct strbuf *buf, const char *fmt, ...)
{
va_list params;
if (!buf)
return;
va_start(params, fmt);
strbuf_vaddf(buf, fmt, params);
va_end(params);
}
int validate_worktree(const struct worktree *wt, struct strbuf *errmsg,
unsigned flags)
{
struct strbuf wt_path = STRBUF_INIT;
struct strbuf realpath = STRBUF_INIT;
char *path = NULL;
int err, ret = -1;
strbuf_addf(&wt_path, "%s/.git", wt->path);
if (is_main_worktree(wt)) {
if (is_directory(wt_path.buf)) {
ret = 0;
goto done;
}
/*
* Main worktree using .git file to point to the
* repository would make it impossible to know where
* the actual worktree is if this function is executed
* from another worktree. No .git file support for now.
*/
strbuf_addf_gently(errmsg,
_("'%s' at main working tree is not the repository directory"),
wt_path.buf);
goto done;
}
/*
* Make sure "gitdir" file points to a real .git file and that
* file points back here.
*/
if (!is_absolute_path(wt->path)) {
strbuf_addf_gently(errmsg,
_("'%s' file does not contain absolute path to the working tree location"),
git_common_path("worktrees/%s/gitdir", wt->id));
goto done;
}
if (flags & WT_VALIDATE_WORKTREE_MISSING_OK &&
!file_exists(wt->path)) {
ret = 0;
goto done;
}
if (!file_exists(wt_path.buf)) {
strbuf_addf_gently(errmsg, _("'%s' does not exist"), wt_path.buf);
goto done;
}
path = xstrdup_or_null(read_gitfile_gently(wt_path.buf, &err));
if (!path) {
strbuf_addf_gently(errmsg, _("'%s' is not a .git file, error code %d"),
wt_path.buf, err);
goto done;
}
strbuf_realpath(&realpath, git_common_path("worktrees/%s", wt->id), 1);
ret = fspathcmp(path, realpath.buf);
if (ret)
strbuf_addf_gently(errmsg, _("'%s' does not point back to '%s'"),
wt->path, git_common_path("worktrees/%s", wt->id));
done:
free(path);
strbuf_release(&wt_path);
strbuf_release(&realpath);
return ret;
}
void update_worktree_location(struct worktree *wt, const char *path_)
{
struct strbuf path = STRBUF_INIT;
if (is_main_worktree(wt))
BUG("can't relocate main worktree");
strbuf_realpath(&path, path_, 1);
if (fspathcmp(wt->path, path.buf)) {
write_file(git_common_path("worktrees/%s/gitdir", wt->id),
"%s/.git", path.buf);
free(wt->path);
wt->path = strbuf_detach(&path, NULL);
}
strbuf_release(&path);
}
int is_worktree_being_rebased(const struct worktree *wt,
const char *target)
{
struct wt_status_state state;
int found_rebase;
memset(&state, 0, sizeof(state));
found_rebase = wt_status_check_rebase(wt, &state) &&
(state.rebase_in_progress ||
state.rebase_interactive_in_progress) &&
state.branch &&
skip_prefix(target, "refs/heads/", &target) &&
!strcmp(state.branch, target);
wt_status_state_free_buffers(&state);
return found_rebase;
}
int is_worktree_being_bisected(const struct worktree *wt,
const char *target)
{
struct wt_status_state state;
int found_bisect;
memset(&state, 0, sizeof(state));
found_bisect = wt_status_check_bisect(wt, &state) &&
state.branch &&
skip_prefix(target, "refs/heads/", &target) &&
!strcmp(state.branch, target);
wt_status_state_free_buffers(&state);
return found_bisect;
}
/*
* note: this function should be able to detect shared symref even if
* HEAD is temporarily detached (e.g. in the middle of rebase or
* bisect). New commands that do similar things should update this
* function as well.
*/
const struct worktree *find_shared_symref(struct worktree **worktrees,
const char *symref,
const char *target)
{
const struct worktree *existing = NULL;
int i = 0;
for (i = 0; worktrees[i]; i++) {
struct worktree *wt = worktrees[i];
const char *symref_target;
struct ref_store *refs;
int flags;
if (wt->is_bare)
continue;
if (wt->is_detached && !strcmp(symref, "HEAD")) {
if (is_worktree_being_rebased(wt, target)) {
existing = wt;
break;
}
if (is_worktree_being_bisected(wt, target)) {
existing = wt;
break;
}
}
refs = get_worktree_ref_store(wt);
symref_target = refs_resolve_ref_unsafe(refs, symref, 0,
NULL, &flags);
if ((flags & REF_ISSYMREF) &&
symref_target && !strcmp(symref_target, target)) {
existing = wt;
break;
}
}
return existing;
}
int submodule_uses_worktrees(const char *path)
{
char *submodule_gitdir;
struct strbuf sb = STRBUF_INIT, err = STRBUF_INIT;
DIR *dir;
struct dirent *d;
int ret = 0;
struct repository_format format = REPOSITORY_FORMAT_INIT;
submodule_gitdir = git_pathdup_submodule(path, "%s", "");
if (!submodule_gitdir)
return 0;
/* The env would be set for the superproject. */
get_common_dir_noenv(&sb, submodule_gitdir);
free(submodule_gitdir);
strbuf_addstr(&sb, "/config");
read_repository_format(&format, sb.buf);
if (verify_repository_format(&format, &err)) {
strbuf_release(&err);
strbuf_release(&sb);
clear_repository_format(&format);
return 1;
}
clear_repository_format(&format);
strbuf_release(&err);
/* Replace config by worktrees. */
strbuf_setlen(&sb, sb.len - strlen("config"));
strbuf_addstr(&sb, "worktrees");
/* See if there is any file inside the worktrees directory. */
dir = opendir(sb.buf);
strbuf_release(&sb);
if (!dir)
return 0;
d = readdir_skip_dot_and_dotdot(dir);
if (d != NULL)
ret = 1;
closedir(dir);
return ret;
}
int parse_worktree_ref(const char *worktree_ref, const char **name,
int *name_length, const char **ref)
{
if (skip_prefix(worktree_ref, "main-worktree/", &worktree_ref)) {
if (!*worktree_ref)
return -1;
if (name)
*name = NULL;
if (name_length)
*name_length = 0;
if (ref)
*ref = worktree_ref;
return 0;
}
if (skip_prefix(worktree_ref, "worktrees/", &worktree_ref)) {
const char *slash = strchr(worktree_ref, '/');
if (!slash || slash == worktree_ref || !slash[1])
return -1;
if (name)
*name = worktree_ref;
if (name_length)
*name_length = slash - worktree_ref;
if (ref)
*ref = slash + 1;
return 0;
}
return -1;
}
void strbuf_worktree_ref(const struct worktree *wt,
struct strbuf *sb,
const char *refname)
{
switch (ref_type(refname)) {
case REF_TYPE_PSEUDOREF:
case REF_TYPE_PER_WORKTREE:
if (wt && !wt->is_current) {
if (is_main_worktree(wt))
strbuf_addstr(sb, "main-worktree/");
else
strbuf_addf(sb, "worktrees/%s/", wt->id);
}
break;
case REF_TYPE_MAIN_PSEUDOREF:
case REF_TYPE_OTHER_PSEUDOREF:
break;
case REF_TYPE_NORMAL:
/*
* For shared refs, don't prefix worktrees/ or
* main-worktree/. It's not necessary and
* files-backend.c can't handle it anyway.
*/
break;
}
strbuf_addstr(sb, refname);
}
int other_head_refs(each_ref_fn fn, void *cb_data)
{
struct worktree **worktrees, **p;
struct strbuf refname = STRBUF_INIT;
int ret = 0;
worktrees = get_worktrees();
for (p = worktrees; *p; p++) {
struct worktree *wt = *p;
struct object_id oid;
int flag;
if (wt->is_current)
continue;
strbuf_reset(&refname);
strbuf_worktree_ref(wt, &refname, "HEAD");
if (refs_resolve_ref_unsafe(get_main_ref_store(the_repository),
refname.buf,
RESOLVE_REF_READING,
&oid, &flag))
ret = fn(refname.buf, &oid, flag, cb_data);
if (ret)
break;
}
free_worktrees(worktrees);
strbuf_release(&refname);
return ret;
}
/*
* Repair worktree's /path/to/worktree/.git file if missing, corrupt, or not
* pointing at <repo>/worktrees/<id>.
*/
static void repair_gitfile(struct worktree *wt,
worktree_repair_fn fn, void *cb_data)
{
struct strbuf dotgit = STRBUF_INIT;
struct strbuf repo = STRBUF_INIT;
char *backlink;
const char *repair = NULL;
int err;
/* missing worktree can't be repaired */
if (!file_exists(wt->path))
return;
if (!is_directory(wt->path)) {
fn(1, wt->path, _("not a directory"), cb_data);
return;
}
strbuf_realpath(&repo, git_common_path("worktrees/%s", wt->id), 1);
strbuf_addf(&dotgit, "%s/.git", wt->path);
backlink = xstrdup_or_null(read_gitfile_gently(dotgit.buf, &err));
if (err == READ_GITFILE_ERR_NOT_A_FILE)
fn(1, wt->path, _(".git is not a file"), cb_data);
else if (err)
repair = _(".git file broken");
else if (fspathcmp(backlink, repo.buf))
repair = _(".git file incorrect");
if (repair) {
fn(0, wt->path, repair, cb_data);
write_file(dotgit.buf, "gitdir: %s", repo.buf);
}
free(backlink);
strbuf_release(&repo);
strbuf_release(&dotgit);
}
static void repair_noop(int iserr, const char *path, const char *msg,
void *cb_data)
{
/* nothing */
}
void repair_worktrees(worktree_repair_fn fn, void *cb_data)
{
struct worktree **worktrees = get_worktrees();
struct worktree **wt = worktrees + 1; /* +1 skips main worktree */
if (!fn)
fn = repair_noop;
for (; *wt; wt++)
repair_gitfile(*wt, fn, cb_data);
free_worktrees(worktrees);
}
static int is_main_worktree_path(const char *path)
{
struct strbuf target = STRBUF_INIT;
struct strbuf maindir = STRBUF_INIT;
int cmp;
strbuf_add_real_path(&target, path);
strbuf_strip_suffix(&target, "/.git");
strbuf_add_real_path(&maindir, get_git_common_dir());
strbuf_strip_suffix(&maindir, "/.git");
cmp = fspathcmp(maindir.buf, target.buf);
strbuf_release(&maindir);
strbuf_release(&target);
return !cmp;
}
/*
* If both the main worktree and linked worktree have been moved, then the
* gitfile /path/to/worktree/.git won't point into the repository, thus we
* won't know which <repo>/worktrees/<id>/gitdir to repair. However, we may
* be able to infer the gitdir by manually reading /path/to/worktree/.git,
* extracting the <id>, and checking if <repo>/worktrees/<id> exists.
*/
static char *infer_backlink(const char *gitfile)
{
struct strbuf actual = STRBUF_INIT;
struct strbuf inferred = STRBUF_INIT;
const char *id;
if (strbuf_read_file(&actual, gitfile, 0) < 0)
goto error;
if (!starts_with(actual.buf, "gitdir:"))
goto error;
if (!(id = find_last_dir_sep(actual.buf)))
goto error;
strbuf_trim(&actual);
id++; /* advance past '/' to point at <id> */
if (!*id)
goto error;
strbuf_git_common_path(&inferred, the_repository, "worktrees/%s", id);
if (!is_directory(inferred.buf))
goto error;
strbuf_release(&actual);
return strbuf_detach(&inferred, NULL);
error:
strbuf_release(&actual);
strbuf_release(&inferred);
return NULL;
}
/*
* Repair <repo>/worktrees/<id>/gitdir if missing, corrupt, or not pointing at
* the worktree's path.
*/
void repair_worktree_at_path(const char *path,
worktree_repair_fn fn, void *cb_data)
{
struct strbuf dotgit = STRBUF_INIT;
struct strbuf realdotgit = STRBUF_INIT;
struct strbuf gitdir = STRBUF_INIT;
struct strbuf olddotgit = STRBUF_INIT;
char *backlink = NULL;
const char *repair = NULL;
int err;
if (!fn)
fn = repair_noop;
if (is_main_worktree_path(path))
goto done;
strbuf_addf(&dotgit, "%s/.git", path);
if (!strbuf_realpath(&realdotgit, dotgit.buf, 0)) {
fn(1, path, _("not a valid path"), cb_data);
goto done;
}
backlink = xstrdup_or_null(read_gitfile_gently(realdotgit.buf, &err));
if (err == READ_GITFILE_ERR_NOT_A_FILE) {
fn(1, realdotgit.buf, _("unable to locate repository; .git is not a file"), cb_data);
goto done;
} else if (err == READ_GITFILE_ERR_NOT_A_REPO) {
if (!(backlink = infer_backlink(realdotgit.buf))) {
fn(1, realdotgit.buf, _("unable to locate repository; .git file does not reference a repository"), cb_data);
goto done;
}
} else if (err) {
fn(1, realdotgit.buf, _("unable to locate repository; .git file broken"), cb_data);
goto done;
}
strbuf_addf(&gitdir, "%s/gitdir", backlink);
if (strbuf_read_file(&olddotgit, gitdir.buf, 0) < 0)
repair = _("gitdir unreadable");
else {
strbuf_rtrim(&olddotgit);
if (fspathcmp(olddotgit.buf, realdotgit.buf))
repair = _("gitdir incorrect");
}
if (repair) {
fn(0, gitdir.buf, repair, cb_data);
write_file(gitdir.buf, "%s", realdotgit.buf);
}
done:
free(backlink);
strbuf_release(&olddotgit);
strbuf_release(&gitdir);
strbuf_release(&realdotgit);
strbuf_release(&dotgit);
}
int should_prune_worktree(const char *id, struct strbuf *reason, char **wtpath, timestamp_t expire)
{
struct stat st;
char *path;
int fd;
size_t len;
ssize_t read_result;
*wtpath = NULL;
if (!is_directory(git_path("worktrees/%s", id))) {
strbuf_addstr(reason, _("not a valid directory"));
return 1;
}
if (file_exists(git_path("worktrees/%s/locked", id)))
return 0;
if (stat(git_path("worktrees/%s/gitdir", id), &st)) {
strbuf_addstr(reason, _("gitdir file does not exist"));
return 1;
}
fd = open(git_path("worktrees/%s/gitdir", id), O_RDONLY);
if (fd < 0) {
strbuf_addf(reason, _("unable to read gitdir file (%s)"),
strerror(errno));
return 1;
}
len = xsize_t(st.st_size);
path = xmallocz(len);
read_result = read_in_full(fd, path, len);
if (read_result < 0) {
strbuf_addf(reason, _("unable to read gitdir file (%s)"),
strerror(errno));
close(fd);
free(path);
return 1;
}
close(fd);
if (read_result != len) {
strbuf_addf(reason,
_("short read (expected %"PRIuMAX" bytes, read %"PRIuMAX")"),
(uintmax_t)len, (uintmax_t)read_result);
free(path);
return 1;
}
while (len && (path[len - 1] == '\n' || path[len - 1] == '\r'))
len--;
if (!len) {
strbuf_addstr(reason, _("invalid gitdir file"));
free(path);
return 1;
}
path[len] = '\0';
if (!file_exists(path)) {
if (stat(git_path("worktrees/%s/index", id), &st) ||
st.st_mtime <= expire) {
strbuf_addstr(reason, _("gitdir file points to non-existent location"));
free(path);
return 1;
} else {
*wtpath = path;
return 0;
}
}
*wtpath = path;
return 0;
}