git-bisect: fix wrong usage of read(1)
[alt-git.git] / pack-check.c
blobf4898732dd8cd8ad2d8599cb13e0d9d96dda753b
1 #include "cache.h"
2 #include "pack.h"
3 #include "pack-revindex.h"
5 struct idx_entry
7 const unsigned char *sha1;
8 off_t offset;
9 };
11 static int compare_entries(const void *e1, const void *e2)
13 const struct idx_entry *entry1 = e1;
14 const struct idx_entry *entry2 = e2;
15 if (entry1->offset < entry2->offset)
16 return -1;
17 if (entry1->offset > entry2->offset)
18 return 1;
19 return 0;
22 static int verify_packfile(struct packed_git *p,
23 struct pack_window **w_curs)
25 off_t index_size = p->index_size;
26 const unsigned char *index_base = p->index_data;
27 SHA_CTX ctx;
28 unsigned char sha1[20], *pack_sig;
29 off_t offset = 0, pack_sig_ofs = p->pack_size - 20;
30 uint32_t nr_objects, i;
31 int err = 0;
32 struct idx_entry *entries;
34 /* Note that the pack header checks are actually performed by
35 * use_pack when it first opens the pack file. If anything
36 * goes wrong during those checks then the call will die out
37 * immediately.
40 SHA1_Init(&ctx);
41 while (offset < pack_sig_ofs) {
42 unsigned int remaining;
43 unsigned char *in = use_pack(p, w_curs, offset, &remaining);
44 offset += remaining;
45 if (offset > pack_sig_ofs)
46 remaining -= (unsigned int)(offset - pack_sig_ofs);
47 SHA1_Update(&ctx, in, remaining);
49 SHA1_Final(sha1, &ctx);
50 pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
51 if (hashcmp(sha1, pack_sig))
52 err = error("%s SHA1 checksum mismatch",
53 p->pack_name);
54 if (hashcmp(index_base + index_size - 40, pack_sig))
55 err = error("%s SHA1 does not match its inddex",
56 p->pack_name);
57 unuse_pack(w_curs);
59 /* Make sure everything reachable from idx is valid. Since we
60 * have verified that nr_objects matches between idx and pack,
61 * we do not do scan-streaming check on the pack file.
63 nr_objects = p->num_objects;
64 entries = xmalloc(nr_objects * sizeof(*entries));
65 /* first sort entries by pack offset, since unpacking them is more efficient that way */
66 for (i = 0; i < nr_objects; i++) {
67 entries[i].sha1 = nth_packed_object_sha1(p, i);
68 if (!entries[i].sha1)
69 die("internal error pack-check nth-packed-object");
70 entries[i].offset = find_pack_entry_one(entries[i].sha1, p);
71 if (!entries[i].offset)
72 die("internal error pack-check find-pack-entry-one");
74 qsort(entries, nr_objects, sizeof(*entries), compare_entries);
76 for (i = 0; i < nr_objects; i++) {
77 void *data;
78 enum object_type type;
79 unsigned long size;
81 data = unpack_entry(p, entries[i].offset, &type, &size);
82 if (!data) {
83 err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
84 sha1_to_hex(entries[i].sha1), p->pack_name,
85 (uintmax_t)entries[i].offset);
86 break;
88 if (check_sha1_signature(entries[i].sha1, data, size, typename(type))) {
89 err = error("packed %s from %s is corrupt",
90 sha1_to_hex(entries[i].sha1), p->pack_name);
91 free(data);
92 break;
94 free(data);
96 free(entries);
98 return err;
102 #define MAX_CHAIN 50
104 static void show_pack_info(struct packed_git *p)
106 uint32_t nr_objects, i, chain_histogram[MAX_CHAIN+1];
108 nr_objects = p->num_objects;
109 memset(chain_histogram, 0, sizeof(chain_histogram));
110 init_pack_revindex();
112 for (i = 0; i < nr_objects; i++) {
113 const unsigned char *sha1;
114 unsigned char base_sha1[20];
115 const char *type;
116 unsigned long size;
117 unsigned long store_size;
118 off_t offset;
119 unsigned int delta_chain_length;
121 sha1 = nth_packed_object_sha1(p, i);
122 if (!sha1)
123 die("internal error pack-check nth-packed-object");
124 offset = find_pack_entry_one(sha1, p);
125 if (!offset)
126 die("internal error pack-check find-pack-entry-one");
128 type = packed_object_info_detail(p, offset, &size, &store_size,
129 &delta_chain_length,
130 base_sha1);
131 printf("%s ", sha1_to_hex(sha1));
132 if (!delta_chain_length)
133 printf("%-6s %lu %lu %"PRIuMAX"\n",
134 type, size, store_size, (uintmax_t)offset);
135 else {
136 printf("%-6s %lu %lu %"PRIuMAX" %u %s\n",
137 type, size, store_size, (uintmax_t)offset,
138 delta_chain_length, sha1_to_hex(base_sha1));
139 if (delta_chain_length <= MAX_CHAIN)
140 chain_histogram[delta_chain_length]++;
141 else
142 chain_histogram[0]++;
146 for (i = 0; i <= MAX_CHAIN; i++) {
147 if (!chain_histogram[i])
148 continue;
149 printf("chain length = %d: %d object%s\n", i,
150 chain_histogram[i], chain_histogram[i] > 1 ? "s" : "");
152 if (chain_histogram[0])
153 printf("chain length > %d: %d object%s\n", MAX_CHAIN,
154 chain_histogram[0], chain_histogram[0] > 1 ? "s" : "");
157 int verify_pack(struct packed_git *p, int verbose)
159 off_t index_size;
160 const unsigned char *index_base;
161 SHA_CTX ctx;
162 unsigned char sha1[20];
163 int err = 0;
164 struct pack_window *w_curs = NULL;
166 if (open_pack_index(p))
167 return error("packfile %s index not opened", p->pack_name);
168 index_size = p->index_size;
169 index_base = p->index_data;
171 /* Verify SHA1 sum of the index file */
172 SHA1_Init(&ctx);
173 SHA1_Update(&ctx, index_base, (unsigned int)(index_size - 20));
174 SHA1_Final(sha1, &ctx);
175 if (hashcmp(sha1, index_base + index_size - 20))
176 err = error("Packfile index for %s SHA1 mismatch",
177 p->pack_name);
179 /* Verify pack file */
180 err |= verify_packfile(p, &w_curs);
181 unuse_pack(&w_curs);
183 if (verbose) {
184 if (err)
185 printf("%s: bad\n", p->pack_name);
186 else {
187 show_pack_info(p);
188 printf("%s: ok\n", p->pack_name);
192 return err;