reflog: change one->many worktree->refnames to use a string_list

Change the FLEX_ARRAY pattern added in bda3a31cc79 (reflog-expire:
Avoid creating new files in a directory inside readdir(3) loop,
2008-01-25) the string-list API instead.

This does not change any behavior, allows us to delete much of this
code as it's replaced by things we get from the string-list API for
free, as a result we need just one struct to keep track of this data,
instead of two.

The "DUP" -> "string_list_append_nodup(..., strbuf_detach(...))"
pattern here is the same as that used in a recent memory leak fix in
b202e51b154 (grep: fix a "path_list" memory leak, 2021-10-22).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/reflog.c b/builtin/reflog.c
index 6989492bf5cdd17dc7c90feade25bf4df4a05dbf..27851c6efb769ea4139567a01348ec9d2a509449 100644 (file)
--- a/builtin/reflog.c
+++ b/builtin/reflog.c
@@ -48,16 +48,9 @@ struct expire_reflog_policy_cb {
        struct commit_list *tips;
 };
 
-struct collected_reflog {
-       struct object_id oid;
-       char reflog[FLEX_ARRAY];
-};
-
-struct collect_reflog_cb {
-       struct collected_reflog **e;
-       int alloc;
-       int nr;
-       struct worktree *wt;
+struct worktree_reflogs {
+       struct worktree *worktree;
+       struct string_list reflogs;
 };
 
 /* Remember to update object flag allocation in object.h */
@@ -403,24 +396,20 @@ static void reflog_expiry_cleanup(void *cb_data)
 
 static int collect_reflog(const char *ref, const struct object_id *oid, int unused, void *cb_data)
 {
-       struct collected_reflog *e;
-       struct collect_reflog_cb *cb = cb_data;
+       struct worktree_reflogs *cb = cb_data;
+       struct worktree *worktree = cb->worktree;
        struct strbuf newref = STRBUF_INIT;
 
        /*
         * Avoid collecting the same shared ref multiple times because
         * they are available via all worktrees.
         */
-       if (!cb->wt->is_current && ref_type(ref) == REF_TYPE_NORMAL)
+       if (!worktree->is_current && ref_type(ref) == REF_TYPE_NORMAL)
                return 0;
 
-       strbuf_worktree_ref(cb->wt, &newref, ref);
-       FLEX_ALLOC_STR(e, reflog, newref.buf);
-       strbuf_release(&newref);
+       strbuf_worktree_ref(worktree, &newref, ref);
+       string_list_append_nodup(&cb->reflogs, strbuf_detach(&newref, NULL));
 
-       oidcpy(&e->oid, oid);
-       ALLOC_GROW(cb->e, cb->nr + 1, cb->alloc);
-       cb->e[cb->nr++] = e;
        return 0;
 }
 
@@ -609,33 +598,33 @@ static int cmd_reflog_expire(int argc, const char **argv, const char *prefix)
        }
 
        if (do_all) {
-               struct collect_reflog_cb collected;
+               struct worktree_reflogs collected = {
+                       .reflogs = STRING_LIST_INIT_DUP,
+               };
+               struct string_list_item *item;
                struct worktree **worktrees, **p;
-               int i;
 
-               memset(&collected, 0, sizeof(collected));
                worktrees = get_worktrees();
                for (p = worktrees; *p; p++) {
                        if (!all_worktrees && !(*p)->is_current)
                                continue;
-                       collected.wt = *p;
+                       collected.worktree = *p;
                        refs_for_each_reflog(get_worktree_ref_store(*p),
                                             collect_reflog, &collected);
                }
                free_worktrees(worktrees);
-               for (i = 0; i < collected.nr; i++) {
-                       struct collected_reflog *e = collected.e[i];
+
+               for_each_string_list_item(item, &collected.reflogs) {
                        struct expire_reflog_policy_cb cb = { .cmd = cmd };
 
-                       set_reflog_expiry_param(&cb.cmd, explicit_expiry, e->reflog);
-                       status |= reflog_expire(e->reflog, flags,
+                       set_reflog_expiry_param(&cb.cmd, explicit_expiry, item->string);
+                       status |= reflog_expire(item->string, flags,
                                                reflog_expiry_prepare,
                                                should_expire_reflog_ent,
                                                reflog_expiry_cleanup,
                                                &cb);
-                       free(e);
                }
-               free(collected.e);
+               string_list_clear(&collected.reflogs, 0);
        }
 
        for (; i < argc; i++) {