pack-objects: abstract away hash algorithm

Instead of using hard-coded instances of the constant 20, use
the_hash_algo to look up the correct constant.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 907e1123317922e553b076c98427c043c2ec468d..f0145236135e9857eb2015de8764cb88781a5fd9 100644 (file)
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -264,6 +264,7 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
        enum object_type type;
        void *buf;
        struct git_istream *st = NULL;
+       const unsigned hashsz = the_hash_algo->rawsz;
 
        if (!usable_delta) {
                if (entry->type == OBJ_BLOB &&
@@ -320,7 +321,7 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
                dheader[pos] = ofs & 127;
                while (ofs >>= 7)
                        dheader[--pos] = 128 | (--ofs & 127);
-               if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+               if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
@@ -332,19 +333,19 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent
        } else if (type == OBJ_REF_DELTA) {
                /*
                 * Deltas with a base reference contain
-                * an additional 20 bytes for the base sha1.
+                * additional bytes for the base object ID.
                 */
-               if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+               if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
                        return 0;
                }
                hashwrite(f, header, hdrlen);
-               hashwrite(f, entry->delta->idx.oid.hash, 20);
-               hdrlen += 20;
+               hashwrite(f, entry->delta->idx.oid.hash, hashsz);
+               hdrlen += hashsz;
        } else {
-               if (limit && hdrlen + datalen + 20 >= limit) {
+               if (limit && hdrlen + datalen + hashsz >= limit) {
                        if (st)
                                close_istream(st);
                        free(buf);
@@ -376,6 +377,7 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
        unsigned char header[MAX_PACK_OBJECT_HEADER],
                      dheader[MAX_PACK_OBJECT_HEADER];
        unsigned hdrlen;
+       const unsigned hashsz = the_hash_algo->rawsz;
 
        if (entry->delta)
                type = (allow_ofs_delta && entry->delta->idx.offset) ?
@@ -411,7 +413,7 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
                dheader[pos] = ofs & 127;
                while (ofs >>= 7)
                        dheader[--pos] = 128 | (--ofs & 127);
-               if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
+               if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
@@ -420,16 +422,16 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
                hdrlen += sizeof(dheader) - pos;
                reused_delta++;
        } else if (type == OBJ_REF_DELTA) {
-               if (limit && hdrlen + 20 + datalen + 20 >= limit) {
+               if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
                hashwrite(f, header, hdrlen);
-               hashwrite(f, entry->delta->idx.oid.hash, 20);
-               hdrlen += 20;
+               hashwrite(f, entry->delta->idx.oid.hash, hashsz);
+               hdrlen += hashsz;
                reused_delta++;
        } else {
-               if (limit && hdrlen + datalen + 20 >= limit) {
+               if (limit && hdrlen + datalen + hashsz >= limit) {
                        unuse_pack(&w_curs);
                        return 0;
                }
@@ -752,7 +754,7 @@ static off_t write_reused_pack(struct hashfile *f)
                die_errno("unable to seek in reused packfile");
 
        if (reuse_packfile_offset < 0)
-               reuse_packfile_offset = reuse_packfile->pack_size - 20;
+               reuse_packfile_offset = reuse_packfile->pack_size - the_hash_algo->rawsz;
 
        total = to_write = reuse_packfile_offset - sizeof(struct pack_header);
 
@@ -1438,7 +1440,7 @@ static void check_object(struct object_entry *entry)
                        if (reuse_delta && !entry->preferred_base)
                                base_ref = use_pack(p, &w_curs,
                                                entry->in_pack_offset + used, NULL);
-                       entry->in_pack_header_size = used + 20;
+                       entry->in_pack_header_size = used + the_hash_algo->rawsz;
                        break;
                case OBJ_OFS_DELTA:
                        buf = use_pack(p, &w_curs,
@@ -1850,7 +1852,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src,
        /* Now some size filtering heuristics. */
        trg_size = trg_entry->size;
        if (!trg_entry->delta) {
-               max_size = trg_size/2 - 20;
+               max_size = trg_size/2 - the_hash_algo->rawsz;
                ref_depth = 1;
        } else {
                max_size = trg_entry->delta_size;