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