git.oblomov.eu Git - git/blob - pack-check.c

   1 #include "cache.h"
   2 #include "pack.h"
   3
   4 static int verify_packfile(struct packed_git *p,
   5                 struct pack_window **w_curs)
   6 {
   7         unsigned long index_size = p->index_size;
   8         void *index_base = p->index_base;
   9         SHA_CTX ctx;
  10         unsigned char sha1[20];
  11         unsigned long pack_size = p->pack_size;
  12         void *pack_base;
  13         struct pack_header *hdr;
  14         int nr_objects, err, i;
  15
  16         /* Header consistency check */
  17         pack_base = use_pack(p, w_curs, 0, NULL);
  18         hdr = (struct pack_header*)pack_base;
  19         if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
  20                 return error("Packfile %s signature mismatch", p->pack_name);
  21         if (!pack_version_ok(hdr->hdr_version))
  22                 return error("Packfile version %d unsupported",
  23                              ntohl(hdr->hdr_version));
  24         nr_objects = ntohl(hdr->hdr_entries);
  25         if (num_packed_objects(p) != nr_objects)
  26                 return error("Packfile claims to have %d objects, "
  27                              "while idx size expects %d", nr_objects,
  28                              num_packed_objects(p));
  29
  30         SHA1_Init(&ctx);
  31         SHA1_Update(&ctx, pack_base, pack_size - 20);
  32         SHA1_Final(sha1, &ctx);
  33         if (hashcmp(sha1, (unsigned char *)pack_base + pack_size - 20))
  34                 return error("Packfile %s SHA1 mismatch with itself",
  35                              p->pack_name);
  36         if (hashcmp(sha1, (unsigned char *)index_base + index_size - 40))
  37                 return error("Packfile %s SHA1 mismatch with idx",
  38                              p->pack_name);
  39
  40         /* Make sure everything reachable from idx is valid.  Since we
  41          * have verified that nr_objects matches between idx and pack,
  42          * we do not do scan-streaming check on the pack file.
  43          */
  44         for (i = err = 0; i < nr_objects; i++) {
  45                 unsigned char sha1[20];
  46                 void *data;
  47                 char type[20];
  48                 unsigned long size, offset;
  49
  50                 if (nth_packed_object_sha1(p, i, sha1))
  51                         die("internal error pack-check nth-packed-object");
  52                 offset = find_pack_entry_one(sha1, p);
  53                 if (!offset)
  54                         die("internal error pack-check find-pack-entry-one");
  55                 data = unpack_entry(p, offset, type, &size);
  56                 if (!data) {
  57                         err = error("cannot unpack %s from %s",
  58                                     sha1_to_hex(sha1), p->pack_name);
  59                         continue;
  60                 }
  61                 if (check_sha1_signature(sha1, data, size, type)) {
  62                         err = error("packed %s from %s is corrupt",
  63                                     sha1_to_hex(sha1), p->pack_name);
  64                         free(data);
  65                         continue;
  66                 }
  67                 free(data);
  68         }
  69
  70         return err;
  71 }
  72
  73
  74 #define MAX_CHAIN 40
  75
  76 static void show_pack_info(struct packed_git *p,
  77                 struct pack_window **w_curs)
  78 {
  79         struct pack_header *hdr;
  80         int nr_objects, i;
  81         unsigned int chain_histogram[MAX_CHAIN];
  82
  83         hdr = (struct pack_header*)use_pack(p, w_curs, 0, NULL);
  84         nr_objects = ntohl(hdr->hdr_entries);
  85         memset(chain_histogram, 0, sizeof(chain_histogram));
  86
  87         for (i = 0; i < nr_objects; i++) {
  88                 unsigned char sha1[20], base_sha1[20];
  89                 char type[20];
  90                 unsigned long size;
  91                 unsigned long store_size;
  92                 unsigned long offset;
  93                 unsigned int delta_chain_length;
  94
  95                 if (nth_packed_object_sha1(p, i, sha1))
  96                         die("internal error pack-check nth-packed-object");
  97                 offset = find_pack_entry_one(sha1, p);
  98                 if (!offset)
  99                         die("internal error pack-check find-pack-entry-one");
 100
 101                 packed_object_info_detail(p, offset, type, &size, &store_size,
 102                                           &delta_chain_length,
 103                                           base_sha1);
 104                 printf("%s ", sha1_to_hex(sha1));
 105                 if (!delta_chain_length)
 106                         printf("%-6s %lu %lu\n", type, size, offset);
 107                 else {
 108                         printf("%-6s %lu %lu %u %s\n", type, size, offset,
 109                                delta_chain_length, sha1_to_hex(base_sha1));
 110                         if (delta_chain_length < MAX_CHAIN)
 111                                 chain_histogram[delta_chain_length]++;
 112                         else
 113                                 chain_histogram[0]++;
 114                 }
 115         }
 116
 117         for (i = 0; i < MAX_CHAIN; i++) {
 118                 if (!chain_histogram[i])
 119                         continue;
 120                 printf("chain length %s %d: %d object%s\n",
 121                        i ? "=" : ">=",
 122                        i ? i : MAX_CHAIN,
 123                        chain_histogram[i],
 124                        1 < chain_histogram[i] ? "s" : "");
 125         }
 126 }
 127
 128 int verify_pack(struct packed_git *p, int verbose)
 129 {
 130         unsigned long index_size = p->index_size;
 131         void *index_base = p->index_base;
 132         SHA_CTX ctx;
 133         unsigned char sha1[20];
 134         int ret;
 135
 136         ret = 0;
 137         /* Verify SHA1 sum of the index file */
 138         SHA1_Init(&ctx);
 139         SHA1_Update(&ctx, index_base, index_size - 20);
 140         SHA1_Final(sha1, &ctx);
 141         if (hashcmp(sha1, (unsigned char *)index_base + index_size - 20))
 142                 ret = error("Packfile index for %s SHA1 mismatch",
 143                             p->pack_name);
 144
 145         if (!ret) {
 146                 /* Verify pack file */
 147                 struct pack_window *w_curs = NULL;
 148                 ret = verify_packfile(p, &w_curs);
 149                 unuse_pack(&w_curs);
 150         }
 151
 152         if (verbose) {
 153                 if (ret)
 154                         printf("%s: bad\n", p->pack_name);
 155                 else {
 156                         struct pack_window *w_curs = NULL;
 157                         show_pack_info(p, &w_curs);
 158                         unuse_pack(&w_curs);
 159                         printf("%s: ok\n", p->pack_name);
 160                 }
 161         }
 162
 163         return ret;
 164 }