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git/worktree.c
Martin Ågren e8805af1c3 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>
2019-03-01 08:52:00 +09:00

585 lines
13 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]);
}
free (worktrees);
}
/**
* Update head_sha1, 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 path = STRBUF_INIT;
struct strbuf worktree_path = STRBUF_INIT;
int is_bare = 0;
strbuf_add_absolute_path(&worktree_path, get_git_common_dir());
is_bare = !strbuf_strip_suffix(&worktree_path, "/.git");
if (is_bare)
strbuf_strip_suffix(&worktree_path, "/.");
strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
worktree = xcalloc(1, sizeof(*worktree));
worktree->path = strbuf_detach(&worktree_path, NULL);
worktree->is_bare = is_bare;
add_head_info(worktree);
strbuf_release(&path);
strbuf_release(&worktree_path);
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);
if (!strbuf_strip_suffix(&worktree_path, "/.git")) {
strbuf_reset(&worktree_path);
strbuf_add_absolute_path(&worktree_path, ".");
strbuf_strip_suffix(&worktree_path, "/.");
}
strbuf_reset(&path);
strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
worktree = xcalloc(1, sizeof(*worktree));
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);
}
static int compare_worktree(const void *a_, const void *b_)
{
const struct worktree *const *a = a_;
const struct worktree *const *b = b_;
return fspathcmp((*a)->path, (*b)->path);
}
struct worktree **get_worktrees(unsigned flags)
{
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;
if (flags & GWT_SORT_LINKED)
/*
* don't sort the first item (main worktree), which will
* always be the first
*/
QSORT(list + 1, counter - 1, compare_worktree);
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 *path;
char *to_free = NULL;
if ((wt = find_worktree_by_suffix(list, arg)))
return wt;
if (prefix)
arg = to_free = prefix_filename(prefix, arg);
path = real_pathdup(arg, 0);
if (!path) {
free(to_free);
return NULL;
}
for (; *list; list++)
if (!fspathcmp(path, real_path((*list)->path)))
break;
free(path);
free(to_free);
return *list;
}
int is_main_worktree(const struct worktree *wt)
{
return !wt->id;
}
const char *worktree_lock_reason(struct worktree *wt)
{
assert(!is_main_worktree(wt));
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;
}
/* 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;
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;
}
ret = fspathcmp(path, real_path(git_common_path("worktrees/%s", wt->id)));
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);
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 &&
starts_with(target, "refs/heads/") &&
!strcmp(state.branch, target + strlen("refs/heads/")));
free(state.branch);
free(state.onto);
return found_rebase;
}
int is_worktree_being_bisected(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_bisect(wt, &state) &&
state.branch &&
starts_with(target, "refs/heads/") &&
!strcmp(state.branch, target + strlen("refs/heads/"));
free(state.branch);
return found_rebase;
}
/*
* 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(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;
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);
/*
* The check below is only known to be good for repository format
* version 0 at the time of writing this code.
*/
strbuf_addstr(&sb, "/config");
read_repository_format(&format, sb.buf);
if (format.version != 0) {
strbuf_release(&sb);
clear_repository_format(&format);
return 1;
}
clear_repository_format(&format);
/* 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;
}
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);
}
const char *worktree_ref(const struct worktree *wt, const char *refname)
{
static struct strbuf sb = STRBUF_INIT;
strbuf_reset(&sb);
strbuf_worktree_ref(wt, &sb, refname);
return sb.buf;
}
int other_head_refs(each_ref_fn fn, void *cb_data)
{
struct worktree **worktrees, **p;
int ret = 0;
worktrees = get_worktrees(0);
for (p = worktrees; *p; p++) {
struct worktree *wt = *p;
struct object_id oid;
int flag;
if (wt->is_current)
continue;
if (!refs_read_ref_full(get_main_ref_store(the_repository),
worktree_ref(wt, "HEAD"),
RESOLVE_REF_READING,
&oid, &flag))
ret = fn(worktree_ref(wt, "HEAD"), &oid, flag, cb_data);
if (ret)
break;
}
free_worktrees(worktrees);
return ret;
}