[PATCH] verify-pack updates.

[git.git] / pack-check.c

diff --git a/pack-check.c b/pack-check.c
new file mode 100644 (file)
index 0000000..9c72397
--- /dev/null
+++ b/pack-check.c
@@ -0,0 +1,112 @@
+#include "cache.h"
+#include "pack.h"
+
+static int verify_packfile(struct packed_git *p)
+{
+       unsigned long index_size = p->index_size;
+       void *index_base = p->index_base;
+       SHA_CTX ctx;
+       unsigned char sha1[20];
+       unsigned long pack_size = p->pack_size;
+       void *pack_base;
+       struct pack_header *hdr;
+       int nr_objects, err, i;
+
+       /* Header consistency check */
+       hdr = p->pack_base;
+       if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
+               return error("Packfile 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);
+       nr_objects = ntohl(hdr->hdr_entries);
+       if (num_packed_objects(p) != nr_objects)
+               return error("Packfile claims to have %d objects, "
+                            "while idx size expects %d", nr_objects,
+                            num_packed_objects(p));
+
+       SHA1_Init(&ctx);
+       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))
+               return error("Packfile %s SHA1 mismatch with itself",
+                            p->pack_name);
+
+       /* Make sure everything reachable from idx is valid.  Since we
+        * have verified that nr_objects matches between idx and pack,
+        * we do not do scan-streaming check on the pack file.
+        */
+       for (i = err = 0; i < nr_objects; i++) {
+               unsigned char sha1[20];
+               struct pack_entry e;
+               void *data;
+               char type[20];
+               unsigned long size;
+
+               if (nth_packed_object_sha1(p, i, sha1))
+                       die("internal error pack-check nth-packed-object");
+               if (!find_pack_entry_one(sha1, &e, p))
+                       die("internal error pack-check find-pack-entry-one");
+               data = unpack_entry_gently(&e, type, &size);
+               if (!data) {
+                       err = error("cannot unpack %s from %s",
+                                   sha1_to_hex(sha1), p->pack_name);
+                       continue;
+               }
+               if (check_sha1_signature(sha1, data, size, type)) {
+                       err = error("cannot packed %s from %s corrupt",
+                                   sha1_to_hex(sha1), p->pack_name);
+                       free(data);
+                       continue;
+               }
+               free(data);
+       }
+
+       return err;
+}
+
+
+static void show_pack_info(struct packed_git *p)
+{
+       /* Next round */
+}
+
+int verify_pack(struct packed_git *p, int verbose)
+{
+       unsigned long index_size = p->index_size;
+       void *index_base = p->index_base;
+       SHA_CTX ctx;
+       unsigned char sha1[20];
+       int ret;
+
+       ret = 0;
+       /* Verify SHA1 sum of the index file */
+       SHA1_Init(&ctx);
+       SHA1_Update(&ctx, index_base, index_size - 20);
+       SHA1_Final(sha1, &ctx);
+       if (memcmp(sha1, index_base + index_size - 20, 20))
+               ret = error("Packfile index for %s SHA1 mismatch",
+                           p->pack_name);
+
+       if (!ret) {
+               /* Verify pack file */
+               use_packed_git(p);
+               ret = verify_packfile(p);
+               unuse_packed_git(p);
+       }
+
+       if (verbose) {
+               if (ret)
+                       printf("%s: bad\n", p->pack_name);
+               else {
+                       show_pack_info(p);
+                       printf("%s: ok\n", p->pack_name);
+               }
+       }
+
+       return ret;
+}