midx: drop unused parameters from add_midx_to_chain()

When loading a chained midx, we build up an array of hashes, one per
layer of the chain. But since the chain is also represented by the
linked list of multi_pack_index structs, nobody actually reads this
array. We pass it to add_midx_to_chain(), but the parameters are
completely ignored.

So we can drop those unused parameters. And then we can see that its
sole caller, load_midx_chain_fd_st(), only cares about one layer hash at a
time (for parsing each line and feeding it to the single-layer midx
code). So we can replace the array with a single object_id on the stack.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/midx.c b/midx.c
index c867b2b6c2b38f9994f75d78b00e3d3d5a1ab656..ca98bfd7c644fece17d47679c6044747c3798c16 100644 (file)
--- a/midx.c
+++ b/midx.c
@@ -264,9 +264,7 @@ static int open_multi_pack_index_chain(const char *chain_file,
 }
 
 static int add_midx_to_chain(struct multi_pack_index *midx,
-                            struct multi_pack_index *midx_chain,
-                            struct object_id *oids,
-                            int n)
+                            struct multi_pack_index *midx_chain)
 {
        if (midx_chain) {
                if (unsigned_add_overflows(midx_chain->num_packs,
@@ -300,21 +298,20 @@ static struct multi_pack_index *load_midx_chain_fd_st(const char *object_dir,
 {
        struct multi_pack_index *midx_chain = NULL;
        struct strbuf buf = STRBUF_INIT;
-       struct object_id *layers = NULL;
        int valid = 1;
        uint32_t i, count;
        FILE *fp = xfdopen(fd, "r");
 
        count = st->st_size / (the_hash_algo->hexsz + 1);
-       CALLOC_ARRAY(layers, count);
 
        for (i = 0; i < count; i++) {
                struct multi_pack_index *m;
+               struct object_id layer;
 
                if (strbuf_getline_lf(&buf, fp) == EOF)
                        break;
 
-               if (get_oid_hex(buf.buf, &layers[i])) {
+               if (get_oid_hex(buf.buf, &layer)) {
                        warning(_("invalid multi-pack-index chain: line '%s' "
                                  "not a hash"),
                                buf.buf);
@@ -325,12 +322,12 @@ static struct multi_pack_index *load_midx_chain_fd_st(const char *object_dir,
                valid = 0;
 
                strbuf_reset(&buf);
-               get_split_midx_filename_ext(&buf, object_dir, layers[i].hash,
+               get_split_midx_filename_ext(&buf, object_dir, layer.hash,
                                            MIDX_EXT_MIDX);
                m = load_multi_pack_index_one(object_dir, buf.buf, local);
 
                if (m) {
-                       if (add_midx_to_chain(m, midx_chain, layers, i)) {
+                       if (add_midx_to_chain(m, midx_chain)) {
                                midx_chain = m;
                                valid = 1;
                        } else {
@@ -343,7 +340,6 @@ static struct multi_pack_index *load_midx_chain_fd_st(const char *object_dir,
                }
        }
 
-       free(layers);
        fclose(fp);
        strbuf_release(&buf);