fsck-cache: fix SIGSEGV on bad tag object
[git.git] / fsck-cache.c
blobfb0d82f3320b7971d50d73893d777e3ddf1bd73b
1 #include <sys/types.h>
2 #include <dirent.h>
4 #include "cache.h"
5 #include "commit.h"
6 #include "tree.h"
7 #include "blob.h"
8 #include "tag.h"
10 #define REACHABLE 0x0001
12 static int show_root = 0;
13 static int show_tags = 0;
14 static int show_unreachable = 0;
15 static unsigned char head_sha1[20];
17 static void check_connectivity(void)
19 int i;
21 /* Look up all the requirements, warn about missing objects.. */
22 for (i = 0; i < nr_objs; i++) {
23 struct object *obj = objs[i];
24 struct object_list *refs;
26 if (!obj->parsed) {
27 printf("missing %s %s\n", obj->type, sha1_to_hex(obj->sha1));
28 continue;
31 for (refs = obj->refs; refs; refs = refs->next) {
32 if (refs->item->parsed)
33 continue;
34 printf("broken link from %7s %s\n",
35 obj->type, sha1_to_hex(obj->sha1));
36 printf(" to %7s %s\n",
37 refs->item->type, sha1_to_hex(refs->item->sha1));
40 /* Don't bother with tag reachability. */
41 if (obj->type == tag_type)
42 continue;
44 if (show_unreachable && !(obj->flags & REACHABLE)) {
45 printf("unreachable %s %s\n", obj->type, sha1_to_hex(obj->sha1));
46 continue;
49 if (!obj->used) {
50 printf("dangling %s %s\n", obj->type,
51 sha1_to_hex(obj->sha1));
57 * The entries in a tree are ordered in the _path_ order,
58 * which means that a directory entry is ordered by adding
59 * a slash to the end of it.
61 * So a directory called "a" is ordered _after_ a file
62 * called "a.c", because "a/" sorts after "a.c".
64 static int verify_ordered(struct tree_entry_list *a, struct tree_entry_list *b)
66 int len1 = strlen(a->name);
67 int len2 = strlen(b->name);
68 int len = len1 < len2 ? len1 : len2;
69 unsigned char c1, c2;
70 int cmp;
72 cmp = memcmp(a->name, b->name, len);
73 if (cmp < 0)
74 return 0;
75 if (cmp > 0)
76 return -1;
79 * Ok, the first <len> characters are the same.
80 * Now we need to order the next one, but turn
81 * a '\0' into a '/' for a directory entry.
83 c1 = a->name[len];
84 c2 = b->name[len];
85 if (!c1 && a->directory)
86 c1 = '/';
87 if (!c2 && b->directory)
88 c2 = '/';
89 return c1 < c2 ? 0 : -1;
92 static int fsck_tree(struct tree *item)
94 int has_full_path = 0;
95 struct tree_entry_list *entry, *last;
97 last = NULL;
98 for (entry = item->entries; entry; entry = entry->next) {
99 if (strchr(entry->name, '/'))
100 has_full_path = 1;
102 if (last) {
103 if (verify_ordered(last, entry) < 0) {
104 fprintf(stderr, "tree %s not ordered\n",
105 sha1_to_hex(item->object.sha1));
106 return -1;
110 last = entry;
113 if (has_full_path) {
114 fprintf(stderr, "warning: fsck-cache: tree %s "
115 "has full pathnames in it\n",
116 sha1_to_hex(item->object.sha1));
119 return 0;
122 static int fsck_commit(struct commit *commit)
124 if (!commit->tree)
125 return -1;
126 if (!commit->parents && show_root)
127 printf("root %s\n", sha1_to_hex(commit->object.sha1));
128 if (!commit->date)
129 printf("bad commit date in %s\n",
130 sha1_to_hex(commit->object.sha1));
131 return 0;
134 static int fsck_tag(struct tag *tag)
136 struct object *tagged = tag->tagged;
138 if (!tagged) {
139 printf("bad object in tag %s\n", sha1_to_hex(tag->object.sha1));
140 return -1;
142 if (!show_tags)
143 return 0;
145 printf("tagged %s %s", tagged->type, sha1_to_hex(tagged->sha1));
146 printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
147 return 0;
150 static int fsck_sha1(unsigned char *sha1)
152 struct object *obj = parse_object(sha1);
153 if (!obj)
154 return -1;
155 if (obj->type == blob_type)
156 return 0;
157 if (obj->type == tree_type)
158 return fsck_tree((struct tree *) obj);
159 if (obj->type == commit_type)
160 return fsck_commit((struct commit *) obj);
161 if (obj->type == tag_type)
162 return fsck_tag((struct tag *) obj);
163 return -1;
167 * This is the sorting chunk size: make it reasonably
168 * big so that we can sort well..
170 #define MAX_SHA1_ENTRIES (1024)
172 struct sha1_entry {
173 unsigned long ino;
174 unsigned char sha1[20];
177 static struct {
178 unsigned long nr;
179 struct sha1_entry *entry[MAX_SHA1_ENTRIES];
180 } sha1_list;
182 static int ino_compare(const void *_a, const void *_b)
184 const struct sha1_entry *a = _a, *b = _b;
185 unsigned long ino1 = a->ino, ino2 = b->ino;
186 return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
189 static void fsck_sha1_list(void)
191 int i, nr = sha1_list.nr;
193 qsort(sha1_list.entry, nr, sizeof(struct sha1_entry *), ino_compare);
194 for (i = 0; i < nr; i++) {
195 struct sha1_entry *entry = sha1_list.entry[i];
196 unsigned char *sha1 = entry->sha1;
198 sha1_list.entry[i] = NULL;
199 if (fsck_sha1(sha1) < 0)
200 fprintf(stderr, "bad sha1 entry '%s'\n", sha1_to_hex(sha1));
201 free(entry);
203 sha1_list.nr = 0;
206 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
208 struct sha1_entry *entry = xmalloc(sizeof(*entry));
209 int nr;
211 entry->ino = ino;
212 memcpy(entry->sha1, sha1, 20);
213 nr = sha1_list.nr;
214 if (nr == MAX_SHA1_ENTRIES) {
215 fsck_sha1_list();
216 nr = 0;
218 sha1_list.entry[nr] = entry;
219 sha1_list.nr = ++nr;
222 static int fsck_dir(int i, char *path)
224 DIR *dir = opendir(path);
225 struct dirent *de;
227 if (!dir) {
228 return error("missing sha1 directory '%s'", path);
231 while ((de = readdir(dir)) != NULL) {
232 char name[100];
233 unsigned char sha1[20];
234 int len = strlen(de->d_name);
236 switch (len) {
237 case 2:
238 if (de->d_name[1] != '.')
239 break;
240 case 1:
241 if (de->d_name[0] != '.')
242 break;
243 continue;
244 case 38:
245 sprintf(name, "%02x", i);
246 memcpy(name+2, de->d_name, len+1);
247 if (get_sha1_hex(name, sha1) < 0)
248 break;
249 add_sha1_list(sha1, de->d_ino);
250 continue;
252 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
254 closedir(dir);
255 return 0;
258 int main(int argc, char **argv)
260 int i, heads;
261 char *sha1_dir;
263 for (i = 1; i < argc; i++) {
264 const char *arg = argv[i];
266 if (!strcmp(arg, "--unreachable")) {
267 show_unreachable = 1;
268 continue;
270 if (!strcmp(arg, "--tags")) {
271 show_tags = 1;
272 continue;
274 if (!strcmp(arg, "--root")) {
275 show_root = 1;
276 continue;
278 if (*arg == '-')
279 usage("fsck-cache [--tags] [[--unreachable] <head-sha1>*]");
282 sha1_dir = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
283 for (i = 0; i < 256; i++) {
284 static char dir[4096];
285 sprintf(dir, "%s/%02x", sha1_dir, i);
286 fsck_dir(i, dir);
288 fsck_sha1_list();
290 heads = 0;
291 for (i = 1; i < argc; i++) {
292 const char *arg = argv[i];
294 if (*arg == '-')
295 continue;
297 if (!get_sha1(arg, head_sha1)) {
298 struct commit *commit = lookup_commit(head_sha1);
299 struct object *obj;
301 /* Error is printed by lookup_commit(). */
302 if (!commit)
303 continue;
305 obj = &commit->object;
306 obj->used = 1;
307 mark_reachable(obj, REACHABLE);
308 heads++;
309 continue;
311 error("expected sha1, got %s", arg);
314 if (!heads) {
315 if (show_unreachable) {
316 fprintf(stderr, "unable to do reachability without a head\n");
317 show_unreachable = 0;
319 fprintf(stderr, "expect dangling commits - potential heads - due to lack of head information\n");
322 check_connectivity();
323 return 0;