A fundamental restriction of linked working trees is that there must
only ever be a single worktree associated with a particular path, thus
"git worktree add" explicitly disallows creation of a new worktree at
the same location as an existing registered worktree. Nevertheless,
users can still "shoot themselves in the foot" by mucking with
administrative files in .git/worktree/<id>/. Worse, "git worktree move"
is careless[1] and allows a worktree to be moved atop a registered but
missing worktree (which can happen, for instance, if the worktree is on
removable media). For instance:
$ git clone foo.git
$ cd foo
$ git worktree add ../bar
$ git worktree add ../baz
$ rm -rf ../bar
$ git worktree move ../baz ../bar
$ git worktree list
.../foo beefd00f [master]
.../bar beefd00f [bar]
.../bar beefd00f [baz]
Help users recover from this form of corruption by teaching "git
worktree prune" to detect when multiple worktrees are associated with
the same path.
[1]: A subsequent commit will fix "git worktree move" validation to be
more strict.
Signed-off-by: Eric Sunshine <sunshine@xxxxxxxxxxxxxx>
---
builtin/worktree.c | 49 ++++++++++++++++++++++++++++++++++-----
t/t2401-worktree-prune.sh | 12 ++++++++++
2 files changed, 55 insertions(+), 6 deletions(-)
diff --git a/builtin/worktree.c b/builtin/worktree.c
index 706ac68751..65492752a7 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -67,7 +67,12 @@ static void delete_worktrees_dir_if_empty(void)
rmdir(git_path("worktrees")); /* ignore failed removal */
}
-static int should_prune_worktree(const char *id, struct strbuf *reason)
+/*
+ * Return true if worktree entry should be pruned, along with the reason for
+ * pruning. Otherwise, return false and the worktree's path, or NULL if it
+ * cannot be determined. Caller is responsible for freeing returned path.
+ */
+static int should_prune_worktree(const char *id, struct strbuf *reason, char **wtpath)
{
struct stat st;
char *path;
@@ -75,6 +80,7 @@ static int should_prune_worktree(const char *id, struct strbuf *reason)
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;
@@ -120,16 +126,17 @@ static int should_prune_worktree(const char *id, struct strbuf *reason)
}
path[len] = '\0';
if (!file_exists(path)) {
- free(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;
}
}
- free(path);
+ *wtpath = path;
return 0;
}
@@ -141,22 +148,52 @@ static void prune_worktree(const char *id, const char *reason)
delete_git_dir(id);
}
+static int prune_cmp(const void *a, const void *b)
+{
+ const struct string_list_item *x = a;
+ const struct string_list_item *y = b;
+ int c;
+
+ if ((c = fspathcmp(x->string, y->string)))
+ return c;
+ /* paths same; sort by .git/worktrees/<id> */
+ return strcmp(x->util, y->util);
+}
+
+static void prune_dups(struct string_list *l)
+{
+ int i;
+
+ QSORT(l->items, l->nr, prune_cmp);
+ for (i = 1; i < l->nr; i++) {
+ if (!fspathcmp(l->items[i].string, l->items[i - 1].string))
+ prune_worktree(l->items[i].util, "duplicate entry");
+ }
+}
+
static void prune_worktrees(void)
{
struct strbuf reason = STRBUF_INIT;
+ struct string_list kept = STRING_LIST_INIT_NODUP;
DIR *dir = opendir(git_path("worktrees"));
struct dirent *d;
if (!dir)
return;
while ((d = readdir(dir)) != NULL) {
+ char *path;
if (is_dot_or_dotdot(d->d_name))
continue;
strbuf_reset(&reason);
- if (!should_prune_worktree(d->d_name, &reason))
- continue;
- prune_worktree(d->d_name, reason.buf);
+ if (should_prune_worktree(d->d_name, &reason, &path))
+ prune_worktree(d->d_name, reason.buf);
+ else if (path)
+ string_list_append(&kept, path)->util = xstrdup(d->d_name);
}
closedir(dir);
+
+ prune_dups(&kept);
+ string_list_clear(&kept, 1);
+
if (!show_only)
delete_worktrees_dir_if_empty();
strbuf_release(&reason);
diff --git a/t/t2401-worktree-prune.sh b/t/t2401-worktree-prune.sh
index b7d6d5d45a..fd3916fee0 100755
--- a/t/t2401-worktree-prune.sh
+++ b/t/t2401-worktree-prune.sh
@@ -92,4 +92,16 @@ test_expect_success 'not prune proper checkouts' '
test -d .git/worktrees/nop
'
+test_expect_success 'prune duplicate (linked/linked)' '
+ test_when_finished rm -fr .git/worktrees w1 w2 &&
+ git worktree add --detach w1 &&
+ git worktree add --detach w2 &&
+ sed "s/w2/w1/" .git/worktrees/w2/gitdir >.git/worktrees/w2/gitdir.new &&
+ mv .git/worktrees/w2/gitdir.new .git/worktrees/w2/gitdir &&
+ git worktree prune --verbose >actual &&
+ test_i18ngrep "duplicate entry" actual &&
+ test -d .git/worktrees/w1 &&
+ ! test -d .git/worktrees/w2
+'
+
test_done
--
2.27.0.90.gabb59f83a2
