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, 3 insertions, 6 deletions

diff --git a/dir.c b/dir.c
index f6795473f7..332f9d8095 100644
--- a/dir.c
+++ b/dir.c
@@ -2127,8 +2127,7 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,
 		for (i = j = 0; j < dir->nr; j++) {
 			if (i &&
 			    check_dir_entry_contains(dir->entries[i - 1], dir->entries[j])) {
-				free(dir->entries[j]);
-				dir->entries[j] = NULL;
+				FREE_AND_NULL(dir->entries[j]);
 			} else {
 				dir->entries[i++] = dir->entries[j];
 			}
@@ -2154,8 +2153,7 @@ int read_directory(struct dir_struct *dir, struct index_state *istate,
 		     dir->untracked->dir_invalidated))
 			istate->cache_changed |= UNTRACKED_CHANGED;
 		if (dir->untracked != istate->untracked) {
-			free(dir->untracked);
-			dir->untracked = NULL;
+			FREE_AND_NULL(dir->untracked);
 		}
 	}
 	return dir->nr;
@@ -2498,8 +2496,7 @@ void write_untracked_extension(struct strbuf *out, struct untracked_cache *untra
 	strbuf_addbuf(out, &untracked->ident);
 
 	strbuf_add(out, ouc, ouc_size(len));
-	free(ouc);
-	ouc = NULL;
+	FREE_AND_NULL(ouc);
 
 	if (!untracked->root) {
 		varint_len = encode_varint(0, varbuf);