From 02e32b7debbcbe5910c11a515801751b349577d7 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 24 Sep 2015 17:08:24 -0400 Subject: [PATCH] notes: document length of fanout path with a constant We know that a fanned-out sha1 in a notes tree cannot be more than "aa/bb/cc/...", and we have an assert() to confirm that. But let's factor out that length into a constant so we can be sure it is used consistently. And even though we assert() earlier, let's replace a strcpy with xsnprintf, so it is clear to a reader that all cases are covered. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- notes.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/notes.c b/notes.c index eacd2a61d..db7792213 100644 --- a/notes.c +++ b/notes.c @@ -539,6 +539,9 @@ static unsigned char determine_fanout(struct int_node *tree, unsigned char n, return fanout + 1; } +/* hex SHA1 + 19 * '/' + NUL */ +#define FANOUT_PATH_MAX 40 + 19 + 1 + static void construct_path_with_fanout(const unsigned char *sha1, unsigned char fanout, char *path) { @@ -551,7 +554,7 @@ static void construct_path_with_fanout(const unsigned char *sha1, path[i++] = '/'; fanout--; } - strcpy(path + i, hex_sha1 + j); + xsnprintf(path + i, FANOUT_PATH_MAX - i, "%s", hex_sha1 + j); } static int for_each_note_helper(struct notes_tree *t, struct int_node *tree, @@ -562,7 +565,7 @@ static int for_each_note_helper(struct notes_tree *t, struct int_node *tree, void *p; int ret = 0; struct leaf_node *l; - static char path[40 + 19 + 1]; /* hex SHA1 + 19 * '/' + NUL */ + static char path[FANOUT_PATH_MAX]; fanout = determine_fanout(tree, n, fanout); for (i = 0; i < 16; i++) { @@ -595,7 +598,7 @@ static int for_each_note_helper(struct notes_tree *t, struct int_node *tree, /* invoke callback with subtree */ unsigned int path_len = l->key_sha1[19] * 2 + fanout; - assert(path_len < 40 + 19); + assert(path_len < FANOUT_PATH_MAX - 1); construct_path_with_fanout(l->key_sha1, fanout, path); /* Create trailing slash, if needed */