sha1_file: use hex_to_bytes()

The path of a loose object contains its hash value encoded into two
substrings of 2 and 38 hexadecimal digits separated by a slash.  The
first part is handed to for_each_file_in_obj_subdir() in decoded form as
subdir_nr.  The current code builds a full hexadecimal representation of
the hash in a temporary buffer, then uses get_oid_hex() to decode it.

Avoid the intermediate step by taking subdir_nr as-is and using
hex_to_bytes() directly on the second substring.  That's shorter and
easier.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sha1_file.c b/sha1_file.c
index 10c3a0083dedee98dc3d48267ad349589adef3f0..a3c32d91d11c51d0f4e33e3a2f93fd1b5f891123 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1884,6 +1884,7 @@ int for_each_file_in_obj_subdir(unsigned int subdir_nr,
        DIR *dir;
        struct dirent *de;
        int r = 0;
+       struct object_id oid;
 
        if (subdir_nr > 0xff)
                BUG("invalid loose object subdirectory: %x", subdir_nr);
@@ -1901,6 +1902,8 @@ int for_each_file_in_obj_subdir(unsigned int subdir_nr,
                return r;
        }
 
+       oid.hash[0] = subdir_nr;
+
        while ((de = readdir(dir))) {
                if (is_dot_or_dotdot(de->d_name))
                        continue;
@@ -1908,20 +1911,15 @@ int for_each_file_in_obj_subdir(unsigned int subdir_nr,
                strbuf_setlen(path, baselen);
                strbuf_addf(path, "/%s", de->d_name);
 
-               if (strlen(de->d_name) == GIT_SHA1_HEXSZ - 2)  {
-                       char hex[GIT_MAX_HEXSZ+1];
-                       struct object_id oid;
-
-                       xsnprintf(hex, sizeof(hex), "%02x%s",
-                                 subdir_nr, de->d_name);
-                       if (!get_oid_hex(hex, &oid)) {
-                               if (obj_cb) {
-                                       r = obj_cb(&oid, path->buf, data);
-                                       if (r)
-                                               break;
-                               }
-                               continue;
+               if (strlen(de->d_name) == GIT_SHA1_HEXSZ - 2 &&
+                   !hex_to_bytes(oid.hash + 1, de->d_name,
+                                 GIT_SHA1_RAWSZ - 1)) {
+                       if (obj_cb) {
+                               r = obj_cb(&oid, path->buf, data);
+                               if (r)
+                                       break;
                        }
+                       continue;
                }
 
                if (cruft_cb) {