Merge branch 'np/pack-check'

* np/pack-check:
  make verify-pack a bit more useful with bad packs

pack-check.c

@@ -25,10 +25,10 @@ static int verify_packfile(struct packed_git *p,
 	off_t index_size = p->index_size;
 	const unsigned char *index_base = p->index_data;
 	SHA_CTX ctx;
-	unsigned char sha1[20];
-	off_t offset = 0, pack_sig = p->pack_size - 20;
+	unsigned char sha1[20], *pack_sig;
+	off_t offset = 0, pack_sig_ofs = p->pack_size - 20;
 	uint32_t nr_objects, i;
-	int err;
+	int err = 0;
 	struct idx_entry *entries;
 
 	/* Note that the pack header checks are actually performed by
@@ -38,21 +38,22 @@ static int verify_packfile(struct packed_git *p,
 	 */
 
 	SHA1_Init(&ctx);
-	while (offset < pack_sig) {
+	while (offset < pack_sig_ofs) {
 		unsigned int remaining;
 		unsigned char *in = use_pack(p, w_curs, offset, &remaining);
 		offset += remaining;
-		if (offset > pack_sig)
-			remaining -= (unsigned int)(offset - pack_sig);
+		if (offset > pack_sig_ofs)
+			remaining -= (unsigned int)(offset - pack_sig_ofs);
 		SHA1_Update(&ctx, in, remaining);
 	}
 	SHA1_Final(sha1, &ctx);
-	if (hashcmp(sha1, use_pack(p, w_curs, pack_sig, NULL)))
-		return error("Packfile %s SHA1 mismatch with itself",
-			     p->pack_name);
-	if (hashcmp(sha1, index_base + index_size - 40))
-		return error("Packfile %s SHA1 mismatch with idx",
-			     p->pack_name);
+	pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
+	if (hashcmp(sha1, pack_sig))
+		err = error("%s SHA1 checksum mismatch",
+			    p->pack_name);
+	if (hashcmp(index_base + index_size - 40, pack_sig))
+		err = error("%s SHA1 does not match its inddex",
+			    p->pack_name);
 	unuse_pack(w_curs);
 
 	/* Make sure everything reachable from idx is valid.  Since we
@@ -72,22 +73,23 @@ static int verify_packfile(struct packed_git *p,
 	}
 	qsort(entries, nr_objects, sizeof(*entries), compare_entries);
 
-	for (i = 0, err = 0; i < nr_objects; i++) {
+	for (i = 0; i < nr_objects; i++) {
 		void *data;
 		enum object_type type;
 		unsigned long size;
 
 		data = unpack_entry(p, entries[i].offset, &type, &size);
 		if (!data) {
-			err = error("cannot unpack %s from %s",
-				    sha1_to_hex(entries[i].sha1), p->pack_name);
-			continue;
+			err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
+				    sha1_to_hex(entries[i].sha1), p->pack_name,
+				    (uintmax_t)entries[i].offset);
+			break;
 		}
 		if (check_sha1_signature(entries[i].sha1, data, size, typename(type))) {
 			err = error("packed %s from %s is corrupt",
 				    sha1_to_hex(entries[i].sha1), p->pack_name);
 			free(data);
-			continue;
+			break;
 		}
 		free(data);
 	}
@@ -158,37 +160,34 @@ int verify_pack(struct packed_git *p, int verbose)
 	const unsigned char *index_base;
 	SHA_CTX ctx;
 	unsigned char sha1[20];
-	int ret;
+	int err = 0;
+	struct pack_window *w_curs = NULL;
 
 	if (open_pack_index(p))
 		return error("packfile %s index not opened", p->pack_name);
 	index_size = p->index_size;
 	index_base = p->index_data;
 
-	ret = 0;
 	/* Verify SHA1 sum of the index file */
 	SHA1_Init(&ctx);
 	SHA1_Update(&ctx, index_base, (unsigned int)(index_size - 20));
 	SHA1_Final(sha1, &ctx);
 	if (hashcmp(sha1, index_base + index_size - 20))
-		ret = error("Packfile index for %s SHA1 mismatch",
+		err = error("Packfile index for %s SHA1 mismatch",
 			    p->pack_name);
 
-	if (!ret) {
-		/* Verify pack file */
-		struct pack_window *w_curs = NULL;
-		ret = verify_packfile(p, &w_curs);
-		unuse_pack(&w_curs);
-	}
+	/* Verify pack file */
+	err |= verify_packfile(p, &w_curs);
+	unuse_pack(&w_curs);
 
 	if (verbose) {
-		if (ret)
+		if (err)
 			printf("%s: bad\n", p->pack_name);
 		else {
 			show_pack_info(p);
 			printf("%s: ok\n", p->pack_name);
 		}
 	}
 
-	return ret;
+	return err;
 }