Shawn PearceChange unpack_entry_gently and its helper functions to use offsets rather than addresses and left counts to supply pack position information. In most cases this makes the code easier to follow, and it reduces the number of local variables in a few functions. It also better prepares this code for mapping partial segments of packs and altering what regions of a pack are mapped while unpacking an entry.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org> --- sha1_file.c | 33 +++++++++++++++------------------ 1 files changed, 15 insertions(+), 18 deletions(-)
Show changes to sha1_file.c +15 −18
diff --git a/sha1_file.c b/sha1_file.c index e6d47c1..558ec4a 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -1041,9 +1041,9 @@ static int packed_object_info(struct pac return 0; } -static void *unpack_compressed_entry(unsigned char *data, - unsigned long size, - unsigned long left) +static void *unpack_compressed_entry(struct packed_git *p, + unsigned long offset, + unsigned long size) { int st; z_stream stream; @@ -1052,8 +1052,8 @@ static void *unpack_compressed_entry(uns buffer = xmalloc(size + 1); buffer[size] = 0; memset(&stream, 0, sizeof(stream)); - stream.next_in = data; - stream.avail_in = left; + stream.next_in = (unsigned char*)p->pack_base + offset; + stream.avail_in = p->pack_size - offset; stream.next_out = buffer; stream.avail_out = size; @@ -1068,21 +1068,22 @@ static void *unpack_compressed_entry(uns return buffer; } -static void *unpack_delta_entry(unsigned char *base_sha1, +static void *unpack_delta_entry(struct packed_git *p, + unsigned long offset, unsigned long delta_size, - unsigned long left, char *type, - unsigned long *sizep, - struct packed_git *p) + unsigned long *sizep) { struct pack_entry base_ent; void *delta_data, *result, *base; unsigned long result_size, base_size; + unsigned char* base_sha1; - if (left < 20) + if ((offset + 20) >= p->pack_size) die("truncated pack file"); /* The base entry _must_ be in the same pack */ + base_sha1 = (unsigned char*)p->pack_base + offset; if (!find_pack_entry_one(base_sha1, &base_ent, p)) die("failed to find delta-pack base object %s", sha1_to_hex(base_sha1)); @@ -1091,8 +1092,7 @@ static void *unpack_delta_entry(unsigned die("failed to read delta-pack base object %s", sha1_to_hex(base_sha1)); - delta_data = unpack_compressed_entry(base_sha1 + 20, - delta_size, left - 20); + delta_data = unpack_compressed_entry(p, offset + 20, delta_size); result = patch_delta(base, base_size, delta_data, delta_size, &result_size); @@ -1124,23 +1124,20 @@ void *unpack_entry_gently(struct pack_en char *type, unsigned long *sizep) { struct packed_git *p = entry->p; - unsigned long offset, size, left; - unsigned char *pack; + unsigned long offset, size; enum object_type kind; offset = unpack_object_header(p, entry->offset, &kind, &size); - pack = (unsigned char *) p->pack_base + offset; - left = p->pack_size - offset; switch (kind) { case OBJ_DELTA: - return unpack_delta_entry(pack, size, left, type, sizep, p); + return unpack_delta_entry(p, offset, size, type, sizep); case OBJ_COMMIT: case OBJ_TREE: case OBJ_BLOB: case OBJ_TAG: strcpy(type, type_names[kind]); *sizep = size; - return unpack_compressed_entry(pack, size, left); + return unpack_compressed_entry(p, offset, size); default: return NULL; }
-- 1.4.2.g6580