commit: fix a segfault when displaying a commit with unreachable parents

diff --git a/pack-check.c b/pack-check.c
index 511f29424a622f62035f1cd3428aeca7ee18f0e2..c0caaee0933382f30cc932731e1e387cc9a03c12 100644 (file)
--- a/pack-check.c
+++ b/pack-check.c
@@ -16,9 +16,9 @@ static int verify_packfile(struct packed_git *p)
        hdr = p->pack_base;
        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
                return error("Packfile %s signature mismatch", p->pack_name);
-       if (hdr->hdr_version != htonl(PACK_VERSION))
-               return error("Packfile version %d different from ours %d",
-                            ntohl(hdr->hdr_version), PACK_VERSION);
+       if (!pack_version_ok(hdr->hdr_version))
+               return error("Packfile version %d unsupported",
+                            ntohl(hdr->hdr_version));
        nr_objects = ntohl(hdr->hdr_entries);
        if (num_packed_objects(p) != nr_objects)
                return error("Packfile claims to have %d objects, "
@@ -29,12 +29,12 @@ static int verify_packfile(struct packed_git *p)
        pack_base = p->pack_base;
        SHA1_Update(&ctx, pack_base, pack_size - 20);
        SHA1_Final(sha1, &ctx);
-       if (memcmp(sha1, index_base + index_size - 40, 20))
-               return error("Packfile %s SHA1 mismatch with idx",
-                            p->pack_name);
-       if (memcmp(sha1, pack_base + pack_size - 20, 20))
+       if (hashcmp(sha1, (unsigned char *)pack_base + pack_size - 20))
                return error("Packfile %s SHA1 mismatch with itself",
                             p->pack_name);
+       if (hashcmp(sha1, (unsigned char *)index_base + index_size - 40))
+               return error("Packfile %s SHA1 mismatch with idx",
+                            p->pack_name);
 
        /* Make sure everything reachable from idx is valid.  Since we
         * have verified that nr_objects matches between idx and pack,
@@ -42,16 +42,16 @@ static int verify_packfile(struct packed_git *p)
         */
        for (i = err = 0; i < nr_objects; i++) {
                unsigned char sha1[20];
-               struct pack_entry e;
                void *data;
                char type[20];
-               unsigned long size;
+               unsigned long size, offset;
 
                if (nth_packed_object_sha1(p, i, sha1))
                        die("internal error pack-check nth-packed-object");
-               if (!find_pack_entry_one(sha1, &e, p))
+               offset = find_pack_entry_one(sha1, p);
+               if (!offset)
                        die("internal error pack-check find-pack-entry-one");
-               data = unpack_entry_gently(&e, type, &size);
+               data = unpack_entry_gently(p, offset, type, &size);
                if (!data) {
                        err = error("cannot unpack %s from %s",
                                    sha1_to_hex(sha1), p->pack_name);
@@ -70,38 +70,57 @@ static int verify_packfile(struct packed_git *p)
 }
 
 
+#define MAX_CHAIN 40
+
 static void show_pack_info(struct packed_git *p)
 {
        struct pack_header *hdr;
        int nr_objects, i;
+       unsigned int chain_histogram[MAX_CHAIN];
 
        hdr = p->pack_base;
        nr_objects = ntohl(hdr->hdr_entries);
+       memset(chain_histogram, 0, sizeof(chain_histogram));
 
        for (i = 0; i < nr_objects; i++) {
                unsigned char sha1[20], base_sha1[20];
-               struct pack_entry e;
                char type[20];
                unsigned long size;
                unsigned long store_size;
-               int delta_chain_length;
+               unsigned long offset;
+               unsigned int delta_chain_length;
 
                if (nth_packed_object_sha1(p, i, sha1))
                        die("internal error pack-check nth-packed-object");
-               if (!find_pack_entry_one(sha1, &e, p))
+               offset = find_pack_entry_one(sha1, p);
+               if (!offset)
                        die("internal error pack-check find-pack-entry-one");
 
-               packed_object_info_detail(&e, type, &size, &store_size,
+               packed_object_info_detail(p, offset, type, &size, &store_size,
                                          &delta_chain_length,
                                          base_sha1);
                printf("%s ", sha1_to_hex(sha1));
                if (!delta_chain_length)
-                       printf("%-6s %lu %u\n", type, size, e.offset);
-               else
-                       printf("%-6s %lu %u %d %s\n", type, size, e.offset,
+                       printf("%-6s %lu %lu\n", type, size, offset);
+               else {
+                       printf("%-6s %lu %lu %u %s\n", type, size, offset,
                               delta_chain_length, sha1_to_hex(base_sha1));
+                       if (delta_chain_length < MAX_CHAIN)
+                               chain_histogram[delta_chain_length]++;
+                       else
+                               chain_histogram[0]++;
+               }
        }
 
+       for (i = 0; i < MAX_CHAIN; i++) {
+               if (!chain_histogram[i])
+                       continue;
+               printf("chain length %s %d: %d object%s\n",
+                      i ? "=" : ">=",
+                      i ? i : MAX_CHAIN,
+                      chain_histogram[i],
+                      1 < chain_histogram[i] ? "s" : "");
+       }
 }
 
 int verify_pack(struct packed_git *p, int verbose)
@@ -117,7 +136,7 @@ int verify_pack(struct packed_git *p, int verbose)
        SHA1_Init(&ctx);
        SHA1_Update(&ctx, index_base, index_size - 20);
        SHA1_Final(sha1, &ctx);
-       if (memcmp(sha1, index_base + index_size - 20, 20))
+       if (hashcmp(sha1, (unsigned char *)index_base + index_size - 20))
                ret = error("Packfile index for %s SHA1 mismatch",
                            p->pack_name);