git/worktree.c
Junio C Hamano 96a806f87a Merge branch 'rj/avoid-switching-to-already-used-branch'
A few subcommands have been taught to stop users from working on a
branch that is being used in another worktree linked to the same
repository.

* rj/avoid-switching-to-already-used-branch:
  switch: reject if the branch is already checked out elsewhere (test)
  rebase: refuse to switch to a branch already checked out elsewhere (test)
  branch: fix die_if_checked_out() when ignore_current_worktree
  worktree: introduce is_shared_symref()
2023-03-19 15:03:11 -07:00

852 lines
21 KiB
C

#include "git-compat-util.h"
#include "alloc.h"
#include "repository.h"
#include "refs.h"
#include "strbuf.h"
#include "worktree.h"
#include "dir.h"
#include "wt-status.h"
#include "config.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.
*/
int is_shared_symref(const struct worktree *wt, const char *symref,
const char *target)
{
const char *symref_target;
struct ref_store *refs;
int flags;
if (wt->is_bare)
return 0;
if (wt->is_detached && !strcmp(symref, "HEAD")) {
if (is_worktree_being_rebased(wt, target))
return 1;
if (is_worktree_being_bisected(wt, target))
return 1;
}
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))
return 1;
return 0;
}
const struct worktree *find_shared_symref(struct worktree **worktrees,
const char *symref,
const char *target)
{
for (int i = 0; worktrees[i]; i++)
if (is_shared_symref(worktrees[i], symref, target))
return worktrees[i];
return NULL;
}
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)
ret = 1;
closedir(dir);
return ret;
}
void strbuf_worktree_ref(const struct worktree *wt,
struct strbuf *sb,
const char *refname)
{
if (parse_worktree_ref(refname, NULL, NULL, NULL) ==
REF_WORKTREE_CURRENT &&
wt && !wt->is_current) {
if (is_main_worktree(wt))
strbuf_addstr(sb, "main-worktree/");
else
strbuf_addf(sb, "worktrees/%s/", wt->id);
}
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;
}
static int move_config_setting(const char *key, const char *value,
const char *from_file, const char *to_file)
{
if (git_config_set_in_file_gently(to_file, key, value))
return error(_("unable to set %s in '%s'"), key, to_file);
if (git_config_set_in_file_gently(from_file, key, NULL))
return error(_("unable to unset %s in '%s'"), key, from_file);
return 0;
}
int init_worktree_config(struct repository *r)
{
int res = 0;
int bare = 0;
struct config_set cs = { { 0 } };
const char *core_worktree;
char *common_config_file;
char *main_worktree_file;
/*
* If the extension is already enabled, then we can skip the
* upgrade process.
*/
if (repository_format_worktree_config)
return 0;
if ((res = git_config_set_gently("extensions.worktreeConfig", "true")))
return error(_("failed to set extensions.worktreeConfig setting"));
common_config_file = xstrfmt("%s/config", r->commondir);
main_worktree_file = xstrfmt("%s/config.worktree", r->commondir);
git_configset_init(&cs);
git_configset_add_file(&cs, common_config_file);
/*
* If core.bare is true in the common config file, then we need to
* move it to the main worktree's config file or it will break all
* worktrees. If it is false, then leave it in place because it
* _could_ be negating a global core.bare=true.
*/
if (!git_configset_get_bool(&cs, "core.bare", &bare) && bare) {
if ((res = move_config_setting("core.bare", "true",
common_config_file,
main_worktree_file)))
goto cleanup;
}
/*
* If core.worktree is set, then the main worktree is located
* somewhere different than the parent of the common Git dir.
* Relocate that value to avoid breaking all worktrees with this
* upgrade to worktree config.
*/
if (!git_configset_get_value(&cs, "core.worktree", &core_worktree)) {
if ((res = move_config_setting("core.worktree", core_worktree,
common_config_file,
main_worktree_file)))
goto cleanup;
}
/*
* Ensure that we use worktree config for the remaining lifetime
* of the current process.
*/
repository_format_worktree_config = 1;
cleanup:
git_configset_clear(&cs);
free(common_config_file);
free(main_worktree_file);
return res;
}