hook: replace hook_list_clear() -> string_list_clear_func()

Replace the custom function with string_list_clear_func() which
is a more common pattern for clearing a string_list.

To be able to do this, rework hook_clear() into hook_free(), so
it can be passed to string_list_clear_func().

A slight complication is the need to keep a copy of the internal
cb data free() pointer, however I think it's worth it since the
API becomes cleaner, e.g. no more calls with NULL function args
like hook_list_clear(hooks, NULL).

In other words, the callers don't need to keep track of hook
internal state to determine when cleanup is necessary or not
(pass NULL) because each `struct hook` now owns its data_free
callback.

Suggested-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/hook.c b/builtin/hook.c
index e641614b84f28c15ac5448fcbbf78d30332e6434..54b737990b070cab205f8abe6d30aaad468c9b18 100644 (file)
--- a/builtin/hook.c
+++ b/builtin/hook.c
@@ -78,7 +78,7 @@ static int list(int argc, const char **argv, const char *prefix,
        }
 
 cleanup:
-       hook_list_clear(head, NULL);
+       string_list_clear_func(head, hook_free);
        free(head);
        return ret;
 }

diff --git a/hook.c b/hook.c
index b0226ed71677a9e5cd7e218246a1280ff95635b9..021110f21646a6b1cb383595bf49ff96208790b1 100644 (file)
--- a/hook.c
+++ b/hook.c
@@ -52,8 +52,10 @@ const char *find_hook(struct repository *r, const char *name)
        return path.buf;
 }
 
-static void hook_clear(struct hook *h, hook_data_free_fn cb_data_free)
+void hook_free(void *p, const char *str UNUSED)
 {
+       struct hook *h = p;
+
        if (!h)
                return;
 
@@ -64,22 +66,12 @@ static void hook_clear(struct hook *h, hook_data_free_fn cb_data_free)
                free((void *)h->u.configured.command);
        }
 
-       if (cb_data_free)
-               cb_data_free(h->feed_pipe_cb_data);
+       if (h->data_free && h->feed_pipe_cb_data)
+               h->data_free(h->feed_pipe_cb_data);
 
        free(h);
 }
 
-void hook_list_clear(struct string_list *hooks, hook_data_free_fn cb_data_free)
-{
-       struct string_list_item *item;
-
-       for_each_string_list_item(item, hooks)
-               hook_clear(item->util, cb_data_free);
-
-       string_list_clear(hooks, 0);
-}
-
 /* Helper to detect and add default "traditional" hooks from the hookdir. */
 static void list_hooks_add_default(struct repository *r, const char *hookname,
                                   struct string_list *hook_list,
@@ -100,9 +92,15 @@ static void list_hooks_add_default(struct repository *r, const char *hookname,
        if (options && options->dir)
                hook_path = absolute_path(hook_path);
 
-       /* Setup per-hook internal state cb data */
-       if (options && options->feed_pipe_cb_data_alloc)
+       /*
+        * Setup per-hook internal state callback data.
+        * When provided, the alloc/free callbacks are always provided
+        * together, so use them to alloc/free the internal hook state.
+        */
+       if (options && options->feed_pipe_cb_data_alloc) {
                h->feed_pipe_cb_data = options->feed_pipe_cb_data_alloc(options->feed_pipe_ctx);
+               h->data_free = options->feed_pipe_cb_data_free;
+       }
 
        h->kind = HOOK_TRADITIONAL;
        h->u.traditional.path = xstrdup(hook_path);
@@ -316,10 +314,16 @@ static void list_hooks_add_configured(struct repository *r,
 
                CALLOC_ARRAY(hook, 1);
 
-               if (options && options->feed_pipe_cb_data_alloc)
+               /*
+                * When provided, the alloc/free callbacks are always provided
+                * together, so use them to alloc/free the internal hook state.
+                */
+               if (options && options->feed_pipe_cb_data_alloc) {
                        hook->feed_pipe_cb_data =
                                options->feed_pipe_cb_data_alloc(
                                        options->feed_pipe_ctx);
+                       hook->data_free = options->feed_pipe_cb_data_free;
+               }
 
                hook->kind = HOOK_CONFIGURED;
                hook->u.configured.friendly_name = xstrdup(friendly_name);
@@ -362,7 +366,7 @@ int hook_exists(struct repository *r, const char *name)
 {
        struct string_list *hooks = list_hooks(r, name, NULL);
        int exists = hooks->nr > 0;
-       hook_list_clear(hooks, NULL);
+       string_list_clear_func(hooks, hook_free);
        free(hooks);
        return exists;
 }
@@ -516,7 +520,7 @@ int run_hooks_opt(struct repository *r, const char *hook_name,
        run_processes_parallel(&opts);
        ret = cb_data.rc;
 cleanup:
-       hook_list_clear(cb_data.hook_command_list, options->feed_pipe_cb_data_free);
+       string_list_clear_func(cb_data.hook_command_list, hook_free);
        free(cb_data.hook_command_list);
        run_hooks_opt_clear(options);
        return ret;

diff --git a/hook.h b/hook.h
index 965794a5b85e126114497780cf585ad7697b9a84..a56ac20ccfbb6f368d284efd3bfadf15bb259b6b 100644 (file)
--- a/hook.h
+++ b/hook.h
@@ -7,6 +7,9 @@
 
 struct repository;
 
+typedef void (*hook_data_free_fn)(void *data);
+typedef void *(*hook_data_alloc_fn)(void *init_ctx);
+
 /**
  * Represents a hook command to be run.
  * Hooks can be:
@@ -41,10 +44,15 @@ struct hook {
         * Only useful when using `run_hooks_opt.feed_pipe`, otherwise ignore it.
         */
        void *feed_pipe_cb_data;
-};
 
-typedef void (*hook_data_free_fn)(void *data);
-typedef void *(*hook_data_alloc_fn)(void *init_ctx);
+       /**
+        * Callback to free `feed_pipe_cb_data`.
+        *
+        * It is called automatically and points to the `feed_pipe_cb_data_free`
+        * provided via the `run_hook_opt` parameter.
+        */
+       hook_data_free_fn data_free;
+};
 
 struct run_hooks_opt {
        /* Environment vars to be set for each hook */
@@ -185,10 +193,10 @@ struct string_list *list_hooks(struct repository *r, const char *hookname,
                               struct run_hooks_opt *options);
 
 /**
- * Frees the memory allocated for the hook list, including the `struct hook`
- * items and their internal state.
+ * Frees a struct hook stored as the util pointer of a string_list_item.
+ * Suitable for use as a string_list_clear_func_t callback.
  */
-void hook_list_clear(struct string_list *hooks, hook_data_free_fn cb_data_free);
+void hook_free(void *p, const char *str);
 
 /**
  * Frees the hook configuration cache stored in `struct repository`.