builtin/show-index.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "gettext.h"
   4 #include "hash.h"
   5 #include "hex.h"
   6 #include "pack.h"
   7 #include "parse-options.h"
   8 #include "repository.h"
   9
  10 static const char *const show_index_usage[] = {
  11         "git show-index [--object-format=<hash-algorithm>]",
  12         NULL
  13 };
  14
  15 int cmd_show_index(int argc, const char **argv, const char *prefix)
  16 {
  17         int i;
  18         unsigned nr;
  19         unsigned int version;
  20         static unsigned int top_index[256];
  21         unsigned hashsz;
  22         const char *hash_name = NULL;
  23         int hash_algo;
  24         const struct option show_index_options[] = {
  25                 OPT_STRING(0, "object-format", &hash_name, N_("hash-algorithm"),
  26                            N_("specify the hash algorithm to use")),
  27                 OPT_END()
  28         };
  29
  30         argc = parse_options(argc, argv, prefix, show_index_options, show_index_usage, 0);
  31
  32         if (hash_name) {
  33                 hash_algo = hash_algo_by_name(hash_name);
  34                 if (hash_algo == GIT_HASH_UNKNOWN)
  35                         die(_("Unknown hash algorithm"));
  36                 repo_set_hash_algo(the_repository, hash_algo);
  37         }
  38
  39         hashsz = the_hash_algo->rawsz;
  40
  41         if (fread(top_index, 2 * 4, 1, stdin) != 1)
  42                 die("unable to read header");
  43         if (top_index[0] == htonl(PACK_IDX_SIGNATURE)) {
  44                 version = ntohl(top_index[1]);
  45                 if (version < 2 || version > 2)
  46                         die("unknown index version");
  47                 if (fread(top_index, 256 * 4, 1, stdin) != 1)
  48                         die("unable to read index");
  49         } else {
  50                 version = 1;
  51                 if (fread(&top_index[2], 254 * 4, 1, stdin) != 1)
  52                         die("unable to read index");
  53         }
  54         nr = 0;
  55         for (i = 0; i < 256; i++) {
  56                 unsigned n = ntohl(top_index[i]);
  57                 if (n < nr)
  58                         die("corrupt index file");
  59                 nr = n;
  60         }
  61         if (version == 1) {
  62                 for (i = 0; i < nr; i++) {
  63                         unsigned int offset, entry[(GIT_MAX_RAWSZ + 4) / sizeof(unsigned int)];
  64
  65                         if (fread(entry, 4 + hashsz, 1, stdin) != 1)
  66                                 die("unable to read entry %u/%u", i, nr);
  67                         offset = ntohl(entry[0]);
  68                         printf("%u %s\n", offset, hash_to_hex((void *)(entry+1)));
  69                 }
  70         } else {
  71                 unsigned off64_nr = 0;
  72                 struct {
  73                         struct object_id oid;
  74                         uint32_t crc;
  75                         uint32_t off;
  76                 } *entries;
  77                 ALLOC_ARRAY(entries, nr);
  78                 for (i = 0; i < nr; i++) {
  79                         if (fread(entries[i].oid.hash, hashsz, 1, stdin) != 1)
  80                                 die("unable to read sha1 %u/%u", i, nr);
  81                         entries[i].oid.algo = hash_algo_by_ptr(the_hash_algo);
  82                 }
  83                 for (i = 0; i < nr; i++)
  84                         if (fread(&entries[i].crc, 4, 1, stdin) != 1)
  85                                 die("unable to read crc %u/%u", i, nr);
  86                 for (i = 0; i < nr; i++)
  87                         if (fread(&entries[i].off, 4, 1, stdin) != 1)
  88                                 die("unable to read 32b offset %u/%u", i, nr);
  89                 for (i = 0; i < nr; i++) {
  90                         uint64_t offset;
  91                         uint32_t off = ntohl(entries[i].off);
  92                         if (!(off & 0x80000000)) {
  93                                 offset = off;
  94                         } else {
  95                                 uint32_t off64[2];
  96                                 if ((off & 0x7fffffff) != off64_nr)
  97                                         die("inconsistent 64b offset index");
  98                                 if (fread(off64, 8, 1, stdin) != 1)
  99                                         die("unable to read 64b offset %u", off64_nr);
 100                                 offset = (((uint64_t)ntohl(off64[0])) << 32) |
 101                                                      ntohl(off64[1]);
 102                                 off64_nr++;
 103                         }
 104                         printf("%" PRIuMAX " %s (%08"PRIx32")\n",
 105                                (uintmax_t) offset,
 106                                oid_to_hex(&entries[i].oid),
 107                                ntohl(entries[i].crc));
 108                 }
 109                 free(entries);
 110         }
 111         return 0;
 112 }