Merge branch 'ab/free-and-null'

A common pattern to free a piece of memory and assign NULL to the
pointer that used to point at it has been replaced with a new
FREE_AND_NULL() macro.

* ab/free-and-null:
  *.[ch] refactoring: make use of the FREE_AND_NULL() macro
  coccinelle: make use of the "expression" FREE_AND_NULL() rule
  coccinelle: add a rule to make "expression" code use FREE_AND_NULL()
  coccinelle: make use of the "type" FREE_AND_NULL() rule
  coccinelle: add a rule to make "type" code use FREE_AND_NULL()
  git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL

1 files changed, 5 insertions, 13 deletions

diff --git a/builtin/am.c b/builtin/am.c
index 7c7b916..c973bd9 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -484,8 +484,7 @@ static int run_applypatch_msg_hook(struct am_state *state)
 	ret = run_hook_le(NULL, "applypatch-msg", am_path(state, "final-commit"), NULL);
 
 	if (!ret) {
-		free(state->msg);
-		state->msg = NULL;
+		FREE_AND_NULL(state->msg);
 		if (read_commit_msg(state) < 0)
 			die(_("'%s' was deleted by the applypatch-msg hook"),
 				am_path(state, "final-commit"));
@@ -1074,17 +1073,10 @@ static void am_next(struct am_state *state)
 {
 	struct object_id head;
 
-	free(state->author_name);
-	state->author_name = NULL;
-
-	free(state->author_email);
-	state->author_email = NULL;
-
-	free(state->author_date);
-	state->author_date = NULL;
-
-	free(state->msg);
-	state->msg = NULL;
+	FREE_AND_NULL(state->author_name);
+	FREE_AND_NULL(state->author_email);
+	FREE_AND_NULL(state->author_date);
+	FREE_AND_NULL(state->msg);
 	state->msg_len = 0;
 
 	unlink(am_path(state, "author-script"));