stash: remove now superfluos help for "stash push"
[git.git] / pack-check.c
blob073c1fbd46dfeeb215c209aa0659768e72b81c3b
1 #include "cache.h"
2 #include "pack.h"
3 #include "pack-revindex.h"
4 #include "progress.h"
5 #include "packfile.h"
7 struct idx_entry {
8 off_t offset;
9 union idx_entry_object {
10 const unsigned char *hash;
11 struct object_id *oid;
12 } oid;
13 unsigned int nr;
16 static int compare_entries(const void *e1, const void *e2)
18 const struct idx_entry *entry1 = e1;
19 const struct idx_entry *entry2 = e2;
20 if (entry1->offset < entry2->offset)
21 return -1;
22 if (entry1->offset > entry2->offset)
23 return 1;
24 return 0;
27 int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
28 off_t offset, off_t len, unsigned int nr)
30 const uint32_t *index_crc;
31 uint32_t data_crc = crc32(0, NULL, 0);
33 do {
34 unsigned long avail;
35 void *data = use_pack(p, w_curs, offset, &avail);
36 if (avail > len)
37 avail = len;
38 data_crc = crc32(data_crc, data, avail);
39 offset += avail;
40 len -= avail;
41 } while (len);
43 index_crc = p->index_data;
44 index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
46 return data_crc != ntohl(*index_crc);
49 static int verify_packfile(struct packed_git *p,
50 struct pack_window **w_curs,
51 verify_fn fn,
52 struct progress *progress, uint32_t base_count)
55 off_t index_size = p->index_size;
56 const unsigned char *index_base = p->index_data;
57 git_SHA_CTX ctx;
58 unsigned char hash[GIT_MAX_RAWSZ], *pack_sig;
59 off_t offset = 0, pack_sig_ofs = 0;
60 uint32_t nr_objects, i;
61 int err = 0;
62 struct idx_entry *entries;
64 if (!is_pack_valid(p))
65 return error("packfile %s cannot be accessed", p->pack_name);
67 git_SHA1_Init(&ctx);
68 do {
69 unsigned long remaining;
70 unsigned char *in = use_pack(p, w_curs, offset, &remaining);
71 offset += remaining;
72 if (!pack_sig_ofs)
73 pack_sig_ofs = p->pack_size - 20;
74 if (offset > pack_sig_ofs)
75 remaining -= (unsigned int)(offset - pack_sig_ofs);
76 git_SHA1_Update(&ctx, in, remaining);
77 } while (offset < pack_sig_ofs);
78 git_SHA1_Final(hash, &ctx);
79 pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
80 if (hashcmp(hash, pack_sig))
81 err = error("%s SHA1 checksum mismatch",
82 p->pack_name);
83 if (hashcmp(index_base + index_size - 40, pack_sig))
84 err = error("%s SHA1 does not match its index",
85 p->pack_name);
86 unuse_pack(w_curs);
88 /* Make sure everything reachable from idx is valid. Since we
89 * have verified that nr_objects matches between idx and pack,
90 * we do not do scan-streaming check on the pack file.
92 nr_objects = p->num_objects;
93 ALLOC_ARRAY(entries, nr_objects + 1);
94 entries[nr_objects].offset = pack_sig_ofs;
95 /* first sort entries by pack offset, since unpacking them is more efficient that way */
96 for (i = 0; i < nr_objects; i++) {
97 entries[i].oid.hash = nth_packed_object_sha1(p, i);
98 if (!entries[i].oid.hash)
99 die("internal error pack-check nth-packed-object");
100 entries[i].offset = nth_packed_object_offset(p, i);
101 entries[i].nr = i;
103 QSORT(entries, nr_objects, compare_entries);
105 for (i = 0; i < nr_objects; i++) {
106 void *data;
107 enum object_type type;
108 unsigned long size;
109 off_t curpos;
110 int data_valid;
112 if (p->index_version > 1) {
113 off_t offset = entries[i].offset;
114 off_t len = entries[i+1].offset - offset;
115 unsigned int nr = entries[i].nr;
116 if (check_pack_crc(p, w_curs, offset, len, nr))
117 err = error("index CRC mismatch for object %s "
118 "from %s at offset %"PRIuMAX"",
119 oid_to_hex(entries[i].oid.oid),
120 p->pack_name, (uintmax_t)offset);
123 curpos = entries[i].offset;
124 type = unpack_object_header(p, w_curs, &curpos, &size);
125 unuse_pack(w_curs);
127 if (type == OBJ_BLOB && big_file_threshold <= size) {
129 * Let check_sha1_signature() check it with
130 * the streaming interface; no point slurping
131 * the data in-core only to discard.
133 data = NULL;
134 data_valid = 0;
135 } else {
136 data = unpack_entry(p, entries[i].offset, &type, &size);
137 data_valid = 1;
140 if (data_valid && !data)
141 err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
142 oid_to_hex(entries[i].oid.oid), p->pack_name,
143 (uintmax_t)entries[i].offset);
144 else if (check_sha1_signature(entries[i].oid.hash, data, size, typename(type)))
145 err = error("packed %s from %s is corrupt",
146 oid_to_hex(entries[i].oid.oid), p->pack_name);
147 else if (fn) {
148 int eaten = 0;
149 err |= fn(entries[i].oid.oid, type, size, data, &eaten);
150 if (eaten)
151 data = NULL;
153 if (((base_count + i) & 1023) == 0)
154 display_progress(progress, base_count + i);
155 free(data);
158 display_progress(progress, base_count + i);
159 free(entries);
161 return err;
164 int verify_pack_index(struct packed_git *p)
166 off_t index_size;
167 const unsigned char *index_base;
168 git_SHA_CTX ctx;
169 unsigned char sha1[20];
170 int err = 0;
172 if (open_pack_index(p))
173 return error("packfile %s index not opened", p->pack_name);
174 index_size = p->index_size;
175 index_base = p->index_data;
177 /* Verify SHA1 sum of the index file */
178 git_SHA1_Init(&ctx);
179 git_SHA1_Update(&ctx, index_base, (unsigned int)(index_size - 20));
180 git_SHA1_Final(sha1, &ctx);
181 if (hashcmp(sha1, index_base + index_size - 20))
182 err = error("Packfile index for %s SHA1 mismatch",
183 p->pack_name);
184 return err;
187 int verify_pack(struct packed_git *p, verify_fn fn,
188 struct progress *progress, uint32_t base_count)
190 int err = 0;
191 struct pack_window *w_curs = NULL;
193 err |= verify_pack_index(p);
194 if (!p->index_data)
195 return -1;
197 err |= verify_packfile(p, &w_curs, fn, progress, base_count);
198 unuse_pack(&w_curs);
200 return err;