"git pull --tags": error out with a better message.
[git] / show-index.c
1 #include "cache.h"
2 #include "pack.h"
3
4 int main(int argc, char **argv)
5 {
6         int i;
7         unsigned nr;
8         unsigned int version;
9         static unsigned int top_index[256];
10
11         if (fread(top_index, 2 * 4, 1, stdin) != 1)
12                 die("unable to read header");
13         if (top_index[0] == htonl(PACK_IDX_SIGNATURE)) {
14                 version = ntohl(top_index[1]);
15                 if (version < 2 || version > 2)
16                         die("unknown index version");
17                 if (fread(top_index, 256 * 4, 1, stdin) != 1)
18                         die("unable to read index");
19         } else {
20                 version = 1;
21                 if (fread(&top_index[2], 254 * 4, 1, stdin) != 1)
22                         die("unable to read index");
23         }
24         nr = 0;
25         for (i = 0; i < 256; i++) {
26                 unsigned n = ntohl(top_index[i]);
27                 if (n < nr)
28                         die("corrupt index file");
29                 nr = n;
30         }
31         if (version == 1) {
32                 for (i = 0; i < nr; i++) {
33                         unsigned int offset, entry[6];
34
35                         if (fread(entry, 4 + 20, 1, stdin) != 1)
36                                 die("unable to read entry %u/%u", i, nr);
37                         offset = ntohl(entry[0]);
38                         printf("%u %s\n", offset, sha1_to_hex((void *)(entry+1)));
39                 }
40         } else {
41                 unsigned off64_nr = 0;
42                 struct {
43                         unsigned char sha1[20];
44                         uint32_t crc;
45                         uint32_t off;
46                 } *entries = xmalloc(nr * sizeof(entries[0]));
47                 for (i = 0; i < nr; i++)
48                         if (fread(entries[i].sha1, 20, 1, stdin) != 1)
49                                 die("unable to read sha1 %u/%u", i, nr);
50                 for (i = 0; i < nr; i++)
51                         if (fread(&entries[i].crc, 4, 1, stdin) != 1)
52                                 die("unable to read crc %u/%u", i, nr);
53                 for (i = 0; i < nr; i++)
54                         if (fread(&entries[i].off, 4, 1, stdin) != 1)
55                                 die("unable to read 32b offset %u/%u", i, nr);
56                 for (i = 0; i < nr; i++) {
57                         uint64_t offset;
58                         uint32_t off = ntohl(entries[i].off);
59                         if (!(off & 0x80000000)) {
60                                 offset = off;
61                         } else {
62                                 uint32_t off64[2];
63                                 if ((off & 0x7fffffff) != off64_nr)
64                                         die("inconsistent 64b offset index");
65                                 if (fread(off64, 8, 1, stdin) != 1)
66                                         die("unable to read 64b offset %u", off64_nr);
67                                 offset = (((uint64_t)ntohl(off64[0])) << 32) |
68                                                      ntohl(off64[1]);
69                                 off64_nr++;
70                         }
71                         printf("%" PRIuMAX " %s (%08x)\n", (uintmax_t) offset,
72                                sha1_to_hex(entries[i].sha1),
73                                ntohl(entries[i].crc));
74                 }
75                 free(entries);
76         }
77         return 0;
78 }