[PATCH 02/13] gc: use hook library for pre-auto-gc hook

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

From: Emily Shaffer <emilyshaffer@google.com>

Move the pre-auto-gc hook away from run-command.h to and over to the
new hook.h library.

To do this introduce a simple run_hooks_oneshot() wrapper, we'll be
using it extensively for these simple cases of wanting to run a single
hook under a given name, and having it free the memory we allocate for
us.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 builtin/gc.c |  3 ++-
 hook.c       | 20 ++++++++++++++++++++
 hook.h       | 13 +++++++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/builtin/gc.c b/builtin/gc.c
index 6b3de3dd514..95939e77f53 100644
--- a/builtin/gc.c
+++ b/builtin/gc.c
@@ -32,6 +32,7 @@
 #include "remote.h"
 #include "object-store.h"
 #include "exec-cmd.h"
+#include "hook.h"
 
 #define FAILED_RUN "failed to run %s"
 
@@ -394,7 +395,7 @@ static int need_to_gc(void)
 	else
 		return 0;
 
-	if (run_hook_le(NULL, "pre-auto-gc", NULL))
+	if (run_hooks_oneshot("pre-auto-gc", NULL))
 		return 0;
 	return 1;
 }
diff --git a/hook.c b/hook.c
index 240270db64e..bfdc79e2f1a 100644
--- a/hook.c
+++ b/hook.c
@@ -141,3 +141,23 @@ int run_hooks(const char *hook_name, const char *hook_path,
 
 	return cb_data.rc;
 }
+
+int run_hooks_oneshot(const char *hook_name, struct run_hooks_opt *options)
+{
+	const char *hook_path;
+	struct run_hooks_opt hook_opt_scratch = RUN_HOOKS_OPT_INIT;
+	int ret = 0;
+
+	if (!options)
+		options = &hook_opt_scratch;
+
+	hook_path = find_hook(hook_name);
+	if (!hook_path)
+		goto cleanup;
+
+	ret = run_hooks(hook_name, hook_path, options);
+cleanup:
+	run_hooks_opt_clear(options);
+
+	return ret;
+}
diff --git a/hook.h b/hook.h
index 111c5cf9296..a2b8d4fc6bd 100644
--- a/hook.h
+++ b/hook.h
@@ -49,7 +49,20 @@ void run_hooks_opt_clear(struct run_hooks_opt *o);
 /**
  * Takes an already resolved hook found via find_hook() and runs
  * it. Does not call run_hooks_opt_clear() for you.
+ *
+ * See run_hooks_oneshot() for the simpler one-shot API.
  */
 int run_hooks(const char *hookname, const char *hook_path,
 	      struct run_hooks_opt *options);
+
+/**
+ * Calls find_hook() on your "hook_name" and runs the hooks (if any)
+ * with run_hooks().
+ *
+ * If "options" is provided calls run_hooks_opt_clear() on it for
+ * you. If "options" is NULL the default options from
+ * RUN_HOOKS_OPT_INIT will be used.
+ */
+int run_hooks_oneshot(const char *hook_name, struct run_hooks_opt *options);
+
 #endif
-- 
2.33.0.1567.g7b23ce7ed9e