git/worktree.c

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#include "cache.h"
#include "repository.h"
#include "refs.h"
#include "strbuf.h"
#include "worktree.h"
#include "dir.h"
2016-04-22 13:01:33 +00:00
#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",
branch: fix branch renaming not updating HEADs correctly There are two bugs that sort of work together and cause problems. Let's start with one in replace_each_worktree_head_symref. Before fa099d2322 (worktree.c: kill parse_ref() in favor of refs_resolve_ref_unsafe() - 2017-04-24), this code looks like this: if (strcmp(oldref, worktrees[i]->head_ref)) continue; set_worktree_head_symref(...); After fa099d2322, it is possible that head_ref can be NULL. However, the updated code takes the wrong exit. In the error case (NULL head_ref), we should "continue;" to the next worktree. The updated code makes us _skip_ "continue;" and update HEAD anyway. The NULL head_ref is triggered by the second bug in add_head_info (in the same commit). With the flag RESOLVE_REF_READING, resolve_ref_unsafe() will abort if it cannot resolve the target ref. For orphan checkouts, HEAD always points to an unborned branch, resolving target ref will always fail. Now we have NULL head_ref. Now we always update HEAD. Correct the logic in replace_ function so that we don't accidentally update HEAD on error. As it turns out, correcting the logic bug above breaks branch renaming completely, thanks to the second bug. "git branch -[Mm]" does two steps (on a normal checkout, no orphan!): - rename the branch on disk (e.g. refs/heads/abc to refs/heads/def) - update HEAD if it points to the branch being renamed. At the second step, since the branch pointed to by HEAD (e.g. "abc") no longer exists on disk, we run into a temporary orphan checkout situation that has been just corrected to _not_ update HEAD. But we need to update HEAD since it's not actually an orphan checkout. We need to update HEAD to move out of that orphan state. Correct add_head_info(), remove RESOLVE_REF_READING flag. With the flag gone, we should always return good "head_ref" in orphan checkouts (either temporary or permanent). With good head_ref, things start to work again. Noticed-by: Nish Aravamudan <nish.aravamudan@canonical.com> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-24 10:41:24 +00:00
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;
worktree: retire special-case normalization of main worktree path In order for "git-worktree list" to present consistent results, get_main_worktree() performs manual normalization on the repository path (returned by get_common_dir()) after passing it through strbuf_add_absolute_path(). In particular, it cleans up the path for three distinct cases when the current working directory is (1) the main worktree, (2) the .git/ subdirectory, or (3) a bare repository. The need for such special-cases is a direct consequence of employing strbuf_add_absolute_path() which, for the sake of efficiency, doesn't bother normalizing the path (such as folding out redundant path components) after making it absolute. Lack of normalization is not typically a problem since redundant path elements make no difference when working with paths at the filesystem level. However, when preparing paths for presentation, possible redundant path components make it difficult to ensure consistency. Eliminate the need for these special cases by instead making the path absolute via strbuf_add_real_path() which normalizes the path for us. Once normalized, the only case we need to handle manually is converting it to the path of the main worktree by stripping the "/.git" suffix. This stripping of the "/.git" suffix is a regular idiom in worktree-related code; for instance, it is employed by get_linked_worktree(), as well. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-31 23:32:14 +00:00
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);
worktree: update is_bare heuristics When "git branch -D <name>" is run, Git usually first checks if that branch is currently checked out. But this check is not performed if the Git directory of that repository is not at "<repo>/.git", which is the case if that repository is a submodule that has its Git directory stored as "super/.git/modules/<repo>", for example. This results in the branch being deleted even though it is checked out. This is because get_main_worktree() in worktree.c sets is_bare on a worktree only using the heuristic that a repo is bare if the worktree's path does not end in "/.git", and not bare otherwise. This is_bare code was introduced in 92718b7438 ("worktree: add details to the worktree struct", 2015-10-08), following a pre-core.bare heuristic. This patch does 2 things: - Teach get_main_worktree() to use is_bare_repository() instead, introduced in 7d1864ce67 ("Introduce is_bare_repository() and core.bare configuration variable", 2007-01-07) and updated in e90fdc39b6 ("Clean up work-tree handling", 2007-08-01). This solves the "git branch -D <name>" problem described above. However... - If a repository has core.bare=1 but the "git" command is being run from one of its secondary worktrees, is_bare_repository() returns false (which is fine, since there is a worktree available). However, treating the main worktree as non-bare when it is bare causes issues: for example, failure to delete a branch from a secondary worktree that is referred to by a main worktree's HEAD, even if that main worktree is bare. In order to avoid that, also check core.bare when setting is_bare. If core.bare=1, trust it, and otherwise, use is_bare_repository(). Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-19 17:21:28 +00:00
/*
* 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);
worktree: drop bogus and unnecessary path munging The content of .git/worktrees/<id>/gitdir must be a path of the form "/path/to/worktree/.git". Any other content would be indicative of a corrupt "gitdir" file. To determine the path of the worktree itself one merely strips the "/.git" suffix, and this is indeed how the worktree path was determined from inception. However, 5193490442 (worktree: add a function to get worktree details, 2015-10-08) extended the path manipulation in a mysterious way. If it is unable to strip "/.git" from the path, then it instead reports the current working directory as the linked worktree's path: if (!strbuf_strip_suffix(&worktree_path, "/.git")) { strbuf_reset(&worktree_path); strbuf_add_absolute_path(&worktree_path, "."); strbuf_strip_suffix(&worktree_path, "/."); } This logic is clearly bogus; it can never be generally correct behavior. It materialized out of thin air in 5193490442 with neither explanation nor tests to illustrate a case in which it would be desirable. It's possible that this logic was introduced to somehow deal with a corrupt "gitdir" file, so that it returns _some_ sort of meaningful value, but returning the current working directory is not helpful. In fact, it is quite misleading (except in the one specific case when the current directory is the worktree whose "gitdir" entry is corrupt). Moreover, reporting the corrupt value to the user, rather than fibbing about it and hiding it outright, is more helpful since it may aid in diagnosing the problem. Therefore, drop this bogus path munging and restore the logic to the original behavior of merely stripping "/.git". Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-31 23:32:13 +00:00
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(dir)) != NULL) {
struct worktree *linked = NULL;
if (is_dot_or_dotdot(d->d_name))
continue;
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 */
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)
2016-04-22 13:01:33 +00:00
{
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);
2016-04-22 13:01:33 +00:00
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;
}
2016-04-22 13:01:33 +00:00
/*
* 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(const char *symref,
const char *target)
{
const struct worktree *existing = NULL;
static struct worktree **worktrees;
int i = 0;
if (worktrees)
free_worktrees(worktrees);
worktrees = get_worktrees();
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;
2016-04-22 13:01:33 +00:00
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;
}
2016-04-22 13:01:33 +00:00
}
refs = get_worktree_ref_store(wt);
symref_target = refs_resolve_ref_unsafe(refs, symref, 0,
NULL, &flags);
worktree: handle broken symrefs in find_shared_symref() The refs_resolve_ref_unsafe() function may return NULL even with a REF_ISSYMREF flag if a symref points to a broken ref. As a result, it's possible for find_shared_symref() to segfault when it passes NULL to strcmp(). This is hard to trigger for most code paths. We typically pass HEAD to the function as the symref to resolve, and programs like "git branch" will bail much earlier if HEAD isn't valid. I did manage to trigger it through one very obscure sequence: # You have multiple notes refs which conflict. git notes add -m base git notes --ref refs/notes/foo add -m foo # There's left-over cruft in NOTES_MERGE_REF that # makes it a broken symref (in this case we point # to a syntactically invalid ref). echo "ref: refs/heads/master.lock" >.git/NOTES_MERGE_REF # You try to merge the notes. We read the broken value in # order to complain that another notes-merge is # in-progress, but we segfault in find_shared_symref(). git notes merge refs/notes/foo This is obviously silly and almost certainly impossible to trigger accidentally, but it does show that the bug is triggerable from at least one code path. In addition, it would trigger if we saw a transient filesystem error when resolving the pointed-to ref. We can fix this by treating NULL the same as a non-matching symref. Arguably we'd prefer to know if a symref points to "refs/heads/foo", but "refs/heads/foo" is broken. But refs_resolve_ref_unsafe() isn't capable of giving us that information, so this is the best we can do. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-19 17:49:36 +00:00
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;
setup: fix memory leaks with `struct repository_format` After we set up a `struct repository_format`, it owns various pieces of allocated memory. We then either use those members, because we decide we want to use the "candidate" repository format, or we discard the candidate / scratch space. In the first case, we transfer ownership of the memory to a few global variables. In the latter case, we just silently drop the struct and end up leaking memory. Introduce an initialization macro `REPOSITORY_FORMAT_INIT` and a function `clear_repository_format()`, to be used on each side of `read_repository_format()`. To have a clear and simple memory ownership, let all users of `struct repository_format` duplicate the strings that they take from it, rather than stealing the pointers. Call `clear_...()` at the start of `read_...()` instead of just zeroing the struct, since we sometimes enter the function multiple times. Thus, it is important to initialize the struct before calling `read_...()`, so document that. It's also important because we might not even call `read_...()` before we call `clear_...()`, see, e.g., builtin/init-db.c. Teach `read_...()` to clear the struct on error, so that it is reset to a safe state, and document this. (In `setup_git_directory_gently()`, we look at `repo_fmt.hash_algo` even if `repo_fmt.version` is -1, which we weren't actually supposed to do per the API. After this commit, that's ok.) We inherit the existing code's combining "error" and "no version found". Both are signalled through `version == -1` and now both cause us to clear any partial configuration we have picked up. For "extensions.*", that's fine, since they require a positive version number. For "core.bare" and "core.worktree", we're already verifying that we have a non-negative version number before using them. Signed-off-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-02-28 20:36:28 +00:00
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);
setup: fix memory leaks with `struct repository_format` After we set up a `struct repository_format`, it owns various pieces of allocated memory. We then either use those members, because we decide we want to use the "candidate" repository format, or we discard the candidate / scratch space. In the first case, we transfer ownership of the memory to a few global variables. In the latter case, we just silently drop the struct and end up leaking memory. Introduce an initialization macro `REPOSITORY_FORMAT_INIT` and a function `clear_repository_format()`, to be used on each side of `read_repository_format()`. To have a clear and simple memory ownership, let all users of `struct repository_format` duplicate the strings that they take from it, rather than stealing the pointers. Call `clear_...()` at the start of `read_...()` instead of just zeroing the struct, since we sometimes enter the function multiple times. Thus, it is important to initialize the struct before calling `read_...()`, so document that. It's also important because we might not even call `read_...()` before we call `clear_...()`, see, e.g., builtin/init-db.c. Teach `read_...()` to clear the struct on error, so that it is reset to a safe state, and document this. (In `setup_git_directory_gently()`, we look at `repo_fmt.hash_algo` even if `repo_fmt.version` is -1, which we weren't actually supposed to do per the API. After this commit, that's ok.) We inherit the existing code's combining "error" and "no version found". Both are signalled through `version == -1` and now both cause us to clear any partial configuration we have picked up. For "extensions.*", that's fine, since they require a positive version number. For "core.bare" and "core.worktree", we're already verifying that we have a non-negative version number before using them. Signed-off-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-02-28 20:36:28 +00:00
clear_repository_format(&format);
return 1;
}
setup: fix memory leaks with `struct repository_format` After we set up a `struct repository_format`, it owns various pieces of allocated memory. We then either use those members, because we decide we want to use the "candidate" repository format, or we discard the candidate / scratch space. In the first case, we transfer ownership of the memory to a few global variables. In the latter case, we just silently drop the struct and end up leaking memory. Introduce an initialization macro `REPOSITORY_FORMAT_INIT` and a function `clear_repository_format()`, to be used on each side of `read_repository_format()`. To have a clear and simple memory ownership, let all users of `struct repository_format` duplicate the strings that they take from it, rather than stealing the pointers. Call `clear_...()` at the start of `read_...()` instead of just zeroing the struct, since we sometimes enter the function multiple times. Thus, it is important to initialize the struct before calling `read_...()`, so document that. It's also important because we might not even call `read_...()` before we call `clear_...()`, see, e.g., builtin/init-db.c. Teach `read_...()` to clear the struct on error, so that it is reset to a safe state, and document this. (In `setup_git_directory_gently()`, we look at `repo_fmt.hash_algo` even if `repo_fmt.version` is -1, which we weren't actually supposed to do per the API. After this commit, that's ok.) We inherit the existing code's combining "error" and "no version found". Both are signalled through `version == -1` and now both cause us to clear any partial configuration we have picked up. For "extensions.*", that's fine, since they require a positive version number. For "core.bare" and "core.worktree", we're already verifying that we have a non-negative version number before using them. Signed-off-by: Martin Ågren <martin.agren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-02-28 20:36:28 +00:00
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;
while ((d = readdir(dir)) != NULL) {
if (is_dot_or_dotdot(d->d_name))
continue;
ret = 1;
break;
}
closedir(dir);
return ret;
}
refs: new ref types to make per-worktree refs visible to all worktrees One of the problems with multiple worktree is accessing per-worktree refs of one worktree from another worktree. This was sort of solved by multiple ref store, where the code can open the ref store of another worktree and has access to the ref space of that worktree. The problem with this is reporting. "HEAD" in another ref space is also called "HEAD" like in the current ref space. In order to differentiate them, all the code must somehow carry the ref store around and print something like "HEAD from this ref store". But that is not feasible (or possible with a _lot_ of work). With the current design, we pass a reference around as a string (so called "refname"). Extending this design to pass a string _and_ a ref store is a nightmare, especially when handling extended SHA-1 syntax. So we do it another way. Instead of entering a separate ref space, we make refs from other worktrees available in the current ref space. So "HEAD" is always HEAD of the current worktree, but then we can have "worktrees/blah/HEAD" to denote HEAD from a worktree named "blah". This syntax coincidentally matches the underlying directory structure which makes implementation a bit easier. The main worktree has to be treated specially because well... it's special from the beginning. So HEAD from the main worktree is acccessible via the name "main-worktree/HEAD" instead of "worktrees/main/HEAD" because "main" could be just another secondary worktree. This patch also makes it possible to specify refs from one worktree in another one, e.g. git log worktrees/foo/HEAD Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-21 08:08:54 +00:00
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_read_ref_full(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;
}
worktree: teach `repair` to fix multi-directional breakage `git worktree repair` knows how to repair the two-way links between the repository and a worktree as long as a link in one or the other direction is sound. For instance, if a linked worktree is moved (without using `git worktree move`), repair is possible because the worktree still knows the location of the repository even though the repository no longer knows where the worktree is. Similarly, if the repository is moved, repair is possible since the repository still knows the locations of the worktrees even though the worktrees no longer know where the repository is. However, if both the repository and the worktrees are moved, then links are severed in both directions, and no repair is possible. This is the case even when the new worktree locations are specified as arguments to `git worktree repair`. The reason for this limitation is twofold. First, when `repair` consults the worktree's gitfile (/path/to/worktree/.git) to determine the corresponding <repo>/worktrees/<id>/gitdir file to fix, <repo> is the old path to the repository, thus it is unable to fix the `gitdir` file at its new location since it doesn't know where it is. Second, when `repair` consults <repo>/worktrees/<id>/gitdir to find the location of the worktree's gitfile (/path/to/worktree/.git), the path recorded in `gitdir` is the old location of the worktree's gitfile, thus it is unable to repair the gitfile since it doesn't know where it is. Fix these shortcomings by teaching `repair` to attempt to infer the new location of the <repo>/worktrees/<id>/gitdir file when the location recorded in the worktree's gitfile has become stale but the file is otherwise well-formed. The inference is intentionally simple-minded. For each worktree path specified as an argument, `git worktree repair` manually reads the ".git" gitfile at that location and, if it is well-formed, extracts the <id>. It then searches for a corresponding <id> in <repo>/worktrees/ and, if found, concludes that there is a reasonable match and updates <repo>/worktrees/<id>/gitdir to point at the specified worktree path. In order for <repo> to be known, `git worktree repair` must be run in the main worktree or bare repository. `git worktree repair` first attempts to repair each incoming /path/to/worktree/.git gitfile to point at the repository, and then attempts to repair outgoing <repo>/worktrees/<id>/gitdir files to point at the worktrees. This sequence was chosen arbitrarily when originally implemented since the order of fixes is immaterial as long as one side of the two-way link between the repository and a worktree is sound. However, for this new repair technique to work, the order must be reversed. This is because the new inference mechanism, when it is successful, allows the outgoing <repo>/worktrees/<id>/gitdir file to be repaired, thus fixing one side of the two-way link. Once that side is fixed, the other side can be fixed by the existing repair mechanism, hence the order of repairs is now significant. Two safeguards are employed to avoid hijacking a worktree from a different repository if the user accidentally specifies a foreign worktree as an argument. The first, as described above, is that it requires an <id> match between the repository and the worktree. That itself is not foolproof for preventing hijack, so the second safeguard is that the inference will only kick in if the worktree's /path/to/worktree/.git gitfile does not point at a repository. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-21 08:16:01 +00:00
/*
* 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;
worktree: teach `repair` to fix multi-directional breakage `git worktree repair` knows how to repair the two-way links between the repository and a worktree as long as a link in one or the other direction is sound. For instance, if a linked worktree is moved (without using `git worktree move`), repair is possible because the worktree still knows the location of the repository even though the repository no longer knows where the worktree is. Similarly, if the repository is moved, repair is possible since the repository still knows the locations of the worktrees even though the worktrees no longer know where the repository is. However, if both the repository and the worktrees are moved, then links are severed in both directions, and no repair is possible. This is the case even when the new worktree locations are specified as arguments to `git worktree repair`. The reason for this limitation is twofold. First, when `repair` consults the worktree's gitfile (/path/to/worktree/.git) to determine the corresponding <repo>/worktrees/<id>/gitdir file to fix, <repo> is the old path to the repository, thus it is unable to fix the `gitdir` file at its new location since it doesn't know where it is. Second, when `repair` consults <repo>/worktrees/<id>/gitdir to find the location of the worktree's gitfile (/path/to/worktree/.git), the path recorded in `gitdir` is the old location of the worktree's gitfile, thus it is unable to repair the gitfile since it doesn't know where it is. Fix these shortcomings by teaching `repair` to attempt to infer the new location of the <repo>/worktrees/<id>/gitdir file when the location recorded in the worktree's gitfile has become stale but the file is otherwise well-formed. The inference is intentionally simple-minded. For each worktree path specified as an argument, `git worktree repair` manually reads the ".git" gitfile at that location and, if it is well-formed, extracts the <id>. It then searches for a corresponding <id> in <repo>/worktrees/ and, if found, concludes that there is a reasonable match and updates <repo>/worktrees/<id>/gitdir to point at the specified worktree path. In order for <repo> to be known, `git worktree repair` must be run in the main worktree or bare repository. `git worktree repair` first attempts to repair each incoming /path/to/worktree/.git gitfile to point at the repository, and then attempts to repair outgoing <repo>/worktrees/<id>/gitdir files to point at the worktrees. This sequence was chosen arbitrarily when originally implemented since the order of fixes is immaterial as long as one side of the two-way link between the repository and a worktree is sound. However, for this new repair technique to work, the order must be reversed. This is because the new inference mechanism, when it is successful, allows the outgoing <repo>/worktrees/<id>/gitdir file to be repaired, thus fixing one side of the two-way link. Once that side is fixed, the other side can be fixed by the existing repair mechanism, hence the order of repairs is now significant. Two safeguards are employed to avoid hijacking a worktree from a different repository if the user accidentally specifies a foreign worktree as an argument. The first, as described above, is that it requires an <id> match between the repository and the worktree. That itself is not foolproof for preventing hijack, so the second safeguard is that the inference will only kick in if the worktree's /path/to/worktree/.git gitfile does not point at a repository. Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-12-21 08:16:01 +00:00
} 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;
}