[PATCH] clean up pack index handling a bit
[git/git.git] / 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 off_t index_size = p->index_size;
8 const unsigned char *index_base = p->index_data;
9 SHA_CTX ctx;
10 unsigned char sha1[20];
11 off_t offset = 0, pack_sig = p->pack_size - 20;
12 uint32_t nr_objects, i;
13 int err;
14
15 /* Note that the pack header checks are actually performed by
16 * use_pack when it first opens the pack file. If anything
17 * goes wrong during those checks then the call will die out
18 * immediately.
19 */
20
21 SHA1_Init(&ctx);
22 while (offset < pack_sig) {
23 unsigned int remaining;
24 unsigned char *in = use_pack(p, w_curs, offset, &remaining);
25 offset += remaining;
26 if (offset > pack_sig)
27 remaining -= (unsigned int)(offset - pack_sig);
28 SHA1_Update(&ctx, in, remaining);
29 }
30 SHA1_Final(sha1, &ctx);
31 if (hashcmp(sha1, use_pack(p, w_curs, pack_sig, NULL)))
32 return error("Packfile %s SHA1 mismatch with itself",
33 p->pack_name);
34 if (hashcmp(sha1, index_base + index_size - 40))
35 return error("Packfile %s SHA1 mismatch with idx",
36 p->pack_name);
37 unuse_pack(w_curs);
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 nr_objects = num_packed_objects(p);
44 for (i = 0, err = 0; i < nr_objects; i++) {
45 unsigned char sha1[20];
46 void *data;
47 enum object_type type;
48 unsigned long size;
49 off_t offset;
50
51 if (nth_packed_object_sha1(p, i, sha1))
52 die("internal error pack-check nth-packed-object");
53 offset = find_pack_entry_one(sha1, p);
54 if (!offset)
55 die("internal error pack-check find-pack-entry-one");
56 data = unpack_entry(p, offset, &type, &size);
57 if (!data) {
58 err = error("cannot unpack %s from %s",
59 sha1_to_hex(sha1), p->pack_name);
60 continue;
61 }
62 if (check_sha1_signature(sha1, data, size, typename(type))) {
63 err = error("packed %s from %s is corrupt",
64 sha1_to_hex(sha1), p->pack_name);
65 free(data);
66 continue;
67 }
68 free(data);
69 }
70
71 return err;
72 }
73
74
75 #define MAX_CHAIN 40
76
77 static void show_pack_info(struct packed_git *p)
78 {
79 uint32_t nr_objects, i, chain_histogram[MAX_CHAIN];
80
81 nr_objects = num_packed_objects(p);
82 memset(chain_histogram, 0, sizeof(chain_histogram));
83
84 for (i = 0; i < nr_objects; i++) {
85 unsigned char sha1[20], base_sha1[20];
86 const char *type;
87 unsigned long size;
88 unsigned long store_size;
89 off_t offset;
90 unsigned int delta_chain_length;
91
92 if (nth_packed_object_sha1(p, i, sha1))
93 die("internal error pack-check nth-packed-object");
94 offset = find_pack_entry_one(sha1, p);
95 if (!offset)
96 die("internal error pack-check find-pack-entry-one");
97
98 type = packed_object_info_detail(p, offset, &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 %"PRIuMAX"\n",
104 type, size, (uintmax_t)offset);
105 else {
106 printf("%-6s %lu %"PRIuMAX" %u %s\n",
107 type, size, (uintmax_t)offset,
108 delta_chain_length, sha1_to_hex(base_sha1));
109 if (delta_chain_length < MAX_CHAIN)
110 chain_histogram[delta_chain_length]++;
111 else
112 chain_histogram[0]++;
113 }
114 }
115
116 for (i = 0; i < MAX_CHAIN; i++) {
117 if (!chain_histogram[i])
118 continue;
119 printf("chain length %s %d: %d object%s\n",
120 i ? "=" : ">=",
121 i ? i : MAX_CHAIN,
122 chain_histogram[i],
123 1 < chain_histogram[i] ? "s" : "");
124 }
125 }
126
127 int verify_pack(struct packed_git *p, int verbose)
128 {
129 off_t index_size = p->index_size;
130 const unsigned char *index_base = p->index_data;
131 SHA_CTX ctx;
132 unsigned char sha1[20];
133 int ret;
134
135 ret = 0;
136 /* Verify SHA1 sum of the index file */
137 SHA1_Init(&ctx);
138 SHA1_Update(&ctx, index_base, (unsigned int)(index_size - 20));
139 SHA1_Final(sha1, &ctx);
140 if (hashcmp(sha1, index_base + index_size - 20))
141 ret = error("Packfile index for %s SHA1 mismatch",
142 p->pack_name);
143
144 if (!ret) {
145 /* Verify pack file */
146 struct pack_window *w_curs = NULL;
147 ret = verify_packfile(p, &w_curs);
148 unuse_pack(&w_curs);
149 }
150
151 if (verbose) {
152 if (ret)
153 printf("%s: bad\n", p->pack_name);
154 else {
155 show_pack_info(p);
156 printf("%s: ok\n", p->pack_name);
157 }
158 }
159
160 return ret;
161 }