for_each_alternate_ref: use strbuf for path allocation

We have a string with ".../objects" pointing to the alternate object store, and overwrite bits of it to look at other paths in the (potential) git repository holding it. This works because the only path we care about is "refs", which is shorter than "objects". Using a strbuf to hold the path lets us get rid of some magic numbers, and makes it more obvious that the memory operations are safe. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Feb 8, 2017 at 15:52 UTC 5e8c968c6465d35c9047ab3ed522cb08d46386f5
1 file changed +14 -14
transport.c
+14 -14
@@ -1214,34 +1214,34 @@ struct alternate_refs_data {
1214 static int refs_from_alternate_cb(struct alternate_object_database *e,
1215 void *data)
1216 {
1217 - char *other;
1218 - size_t len;
1217 + struct strbuf path = STRBUF_INIT;
1218 + size_t base_len;
1219 struct remote *remote;
1220 struct transport *transport;
1221 const struct ref *extra;
1222 struct alternate_refs_data *cb = data;
1223
1224 - other = real_pathdup(e->path);
1225 - if (!other)
1226 - return 0;
1227 - len = strlen(other);
1228 -
1229 - if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1224 + if (!strbuf_realpath(&path, e->path, 0))
1225 + goto out;
1226 + if (!strbuf_strip_suffix(&path, "/objects"))
1227 goto out;
1228 + base_len = path.len;
1229 +
1230 /* Is this a git repository with refs? */
1232 - memcpy(other + len - 8, "/refs", 6);
1233 - if (!is_directory(other))
1231 + strbuf_addstr(&path, "/refs");
1232 + if (!is_directory(path.buf))
1233 goto out;
1235 - other[len - 8] = '\0';
1236 - remote = remote_get(other);
1237 - transport = transport_get(remote, other);
1234 + strbuf_setlen(&path, base_len);
1235 +
1236 + remote = remote_get(path.buf);
1237 + transport = transport_get(remote, path.buf);
1238 for (extra = transport_get_remote_refs(transport);
1239 extra;
1240 extra = extra->next)
1241 cb->fn(extra, cb->data);
1242 transport_disconnect(transport);
1243 out:
1244 - free(other);
1244 + strbuf_release(&path);
1245 return 0;
1246 }
1247