packfile: use get_be64() for large offsets

The pack-index version 2 format uses two 4-byte integers in network-byte order to represent one 8-byte value. The current implementation has several code clones for stitching these integers together. Use get_be64() to create an 8-byte integer from two 4-byte integers represented this way. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Derrick Stolee committed Jan 17, 2018 at 14:08 UTC ad622a256f0dd0be44ca17f58b3f5b43cedb4320
2 files changed +3 -6
pack-revindex.c
+2 -4
@@ -134,10 +134,8 @@ static void create_pack_revindex(struct packed_git *p)
134 if (!(off & 0x80000000)) {
135 p->revindex[i].offset = off;
136 } else {
137 - p->revindex[i].offset =
138 - ((uint64_t)ntohl(*off_64++)) << 32;
139 - p->revindex[i].offset |=
140 - ntohl(*off_64++);
137 + p->revindex[i].offset = get_be64(off_64);
138 + off_64 += 2;
139 }
140 p->revindex[i].nr = i;
141 }
packfile.c
+1 -2
@@ -1702,8 +1702,7 @@ off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
1702 return off;
1703 index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
1704 check_pack_index_ptr(p, index);
1705 - return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
1706 - ntohl(*((uint32_t *)(index + 4)));
1705 + return get_be64(index);
1706 }
1707 }
1708