fsck-cache.c

   1 #include <sys/types.h>
   2 #include <dirent.h>
   3
   4 #include "cache.h"
   5 #include "commit.h"
   6 #include "tree.h"
   7 #include "blob.h"
   8 #include "tag.h"
   9 #include "pack.h"
  10
  11 #define REACHABLE 0x0001
  12
  13 static int show_root = 0;
  14 static int show_tags = 0;
  15 static int show_unreachable = 0;
  16 static int standalone = 0;
  17 static int check_full = 0;
  18 static int keep_cache_objects = 0;
  19 static unsigned char head_sha1[20];
  20
  21 static void check_connectivity(void)
  22 {
  23         int i;
  24
  25         /* Look up all the requirements, warn about missing objects.. */
  26         for (i = 0; i < nr_objs; i++) {
  27                 struct object *obj = objs[i];
  28                 struct object_list *refs;
  29
  30                 if (!obj->parsed) {
  31                         if (!standalone && has_sha1_file(obj->sha1))
  32                                 ; /* it is in pack */
  33                         else
  34                                 printf("missing %s %s\n",
  35                                        obj->type, sha1_to_hex(obj->sha1));
  36                         continue;
  37                 }
  38
  39                 for (refs = obj->refs; refs; refs = refs->next) {
  40                         if (refs->item->parsed ||
  41                             (!standalone && has_sha1_file(refs->item->sha1)))
  42                                 continue;
  43                         printf("broken link from %7s %s\n",
  44                                obj->type, sha1_to_hex(obj->sha1));
  45                         printf("              to %7s %s\n",
  46                                refs->item->type, sha1_to_hex(refs->item->sha1));
  47                 }
  48
  49                 if (show_unreachable && !(obj->flags & REACHABLE)) {
  50                         printf("unreachable %s %s\n",
  51                                obj->type, sha1_to_hex(obj->sha1));
  52                         continue;
  53                 }
  54
  55                 if (!obj->used) {
  56                         printf("dangling %s %s\n", obj->type,
  57                                sha1_to_hex(obj->sha1));
  58                 }
  59         }
  60 }
  61
  62 /*
  63  * The entries in a tree are ordered in the _path_ order,
  64  * which means that a directory entry is ordered by adding
  65  * a slash to the end of it.
  66  *
  67  * So a directory called "a" is ordered _after_ a file
  68  * called "a.c", because "a/" sorts after "a.c".
  69  */
  70 #define TREE_UNORDERED (-1)
  71 #define TREE_HAS_DUPS  (-2)
  72
  73 static int verify_ordered(struct tree_entry_list *a, struct tree_entry_list *b)
  74 {
  75         int len1 = strlen(a->name);
  76         int len2 = strlen(b->name);
  77         int len = len1 < len2 ? len1 : len2;
  78         unsigned char c1, c2;
  79         int cmp;
  80
  81         cmp = memcmp(a->name, b->name, len);
  82         if (cmp < 0)
  83                 return 0;
  84         if (cmp > 0)
  85                 return TREE_UNORDERED;
  86
  87         /*
  88          * Ok, the first <len> characters are the same.
  89          * Now we need to order the next one, but turn
  90          * a '\0' into a '/' for a directory entry.
  91          */
  92         c1 = a->name[len];
  93         c2 = b->name[len];
  94         if (!c1 && !c2)
  95                 /*
  96                  * git-write-tree used to write out a nonsense tree that has
  97                  * entries with the same name, one blob and one tree.  Make
  98                  * sure we do not have duplicate entries.
  99                  */
 100                 return TREE_HAS_DUPS;
 101         if (!c1 && a->directory)
 102                 c1 = '/';
 103         if (!c2 && b->directory)
 104                 c2 = '/';
 105         return c1 < c2 ? 0 : TREE_UNORDERED;
 106 }
 107
 108 static int fsck_tree(struct tree *item)
 109 {
 110         int has_full_path = 0;
 111         struct tree_entry_list *entry, *last;
 112
 113         last = NULL;
 114         for (entry = item->entries; entry; entry = entry->next) {
 115                 if (strchr(entry->name, '/'))
 116                         has_full_path = 1;
 117
 118                 switch (entry->mode) {
 119                 /*
 120                  * Standard modes..
 121                  */
 122                 case S_IFREG | 0755:
 123                 case S_IFREG | 0644:
 124                 case S_IFLNK:
 125                 case S_IFDIR:
 126                         break;
 127                 /*
 128                  * This is nonstandard, but we had a few of these
 129                  * early on when we honored the full set of mode
 130                  * bits..
 131                  */
 132                 case S_IFREG | 0664:
 133                         break;
 134                 default:
 135                         printf("tree %s has entry %o %s\n",
 136                                 sha1_to_hex(item->object.sha1),
 137                                 entry->mode, entry->name);
 138                 }
 139
 140                 if (last) {
 141                         switch (verify_ordered(last, entry)) {
 142                         case TREE_UNORDERED:
 143                                 fprintf(stderr, "tree %s not ordered\n",
 144                                         sha1_to_hex(item->object.sha1));
 145                                 return -1;
 146                         case TREE_HAS_DUPS:
 147                                 fprintf(stderr, "tree %s has duplicate entries for '%s'\n",
 148                                         sha1_to_hex(item->object.sha1),
 149                                         entry->name);
 150                                 return -1;
 151                         default:
 152                                 break;
 153                         }
 154                 }
 155
 156                 last = entry;
 157         }
 158
 159         if (has_full_path) {
 160                 fprintf(stderr, "warning: git-fsck-cache: tree %s "
 161                         "has full pathnames in it\n",
 162                         sha1_to_hex(item->object.sha1));
 163         }
 164
 165         return 0;
 166 }
 167
 168 static int fsck_commit(struct commit *commit)
 169 {
 170         free(commit->buffer);
 171         commit->buffer = NULL;
 172         if (!commit->tree)
 173                 return -1;
 174         if (!commit->parents && show_root)
 175                 printf("root %s\n", sha1_to_hex(commit->object.sha1));
 176         if (!commit->date)
 177                 printf("bad commit date in %s\n",
 178                        sha1_to_hex(commit->object.sha1));
 179         return 0;
 180 }
 181
 182 static int fsck_tag(struct tag *tag)
 183 {
 184         struct object *tagged = tag->tagged;
 185
 186         if (!tagged) {
 187                 printf("bad object in tag %s\n", sha1_to_hex(tag->object.sha1));
 188                 return -1;
 189         }
 190         if (!show_tags)
 191                 return 0;
 192
 193         printf("tagged %s %s", tagged->type, sha1_to_hex(tagged->sha1));
 194         printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
 195         return 0;
 196 }
 197
 198 static int fsck_sha1(unsigned char *sha1)
 199 {
 200         struct object *obj = parse_object(sha1);
 201         if (!obj)
 202                 return -1;
 203         if (obj->type == blob_type)
 204                 return 0;
 205         if (obj->type == tree_type)
 206                 return fsck_tree((struct tree *) obj);
 207         if (obj->type == commit_type)
 208                 return fsck_commit((struct commit *) obj);
 209         if (obj->type == tag_type)
 210                 return fsck_tag((struct tag *) obj);
 211         return -1;
 212 }
 213
 214 /*
 215  * This is the sorting chunk size: make it reasonably
 216  * big so that we can sort well..
 217  */
 218 #define MAX_SHA1_ENTRIES (1024)
 219
 220 struct sha1_entry {
 221         unsigned long ino;
 222         unsigned char sha1[20];
 223 };
 224
 225 static struct {
 226         unsigned long nr;
 227         struct sha1_entry *entry[MAX_SHA1_ENTRIES];
 228 } sha1_list;
 229
 230 static int ino_compare(const void *_a, const void *_b)
 231 {
 232         const struct sha1_entry *a = _a, *b = _b;
 233         unsigned long ino1 = a->ino, ino2 = b->ino;
 234         return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
 235 }
 236
 237 static void fsck_sha1_list(void)
 238 {
 239         int i, nr = sha1_list.nr;
 240
 241         qsort(sha1_list.entry, nr, sizeof(struct sha1_entry *), ino_compare);
 242         for (i = 0; i < nr; i++) {
 243                 struct sha1_entry *entry = sha1_list.entry[i];
 244                 unsigned char *sha1 = entry->sha1;
 245
 246                 sha1_list.entry[i] = NULL;
 247                 if (fsck_sha1(sha1) < 0)
 248                         fprintf(stderr, "bad sha1 entry '%s'\n", sha1_to_hex(sha1));
 249                 free(entry);
 250         }
 251         sha1_list.nr = 0;
 252 }
 253
 254 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
 255 {
 256         struct sha1_entry *entry = xmalloc(sizeof(*entry));
 257         int nr;
 258
 259         entry->ino = ino;
 260         memcpy(entry->sha1, sha1, 20);
 261         nr = sha1_list.nr;
 262         if (nr == MAX_SHA1_ENTRIES) {
 263                 fsck_sha1_list();
 264                 nr = 0;
 265         }
 266         sha1_list.entry[nr] = entry;
 267         sha1_list.nr = ++nr;
 268 }
 269
 270 static int fsck_dir(int i, char *path)
 271 {
 272         DIR *dir = opendir(path);
 273         struct dirent *de;
 274
 275         if (!dir) {
 276                 return error("missing sha1 directory '%s'", path);
 277         }
 278
 279         while ((de = readdir(dir)) != NULL) {
 280                 char name[100];
 281                 unsigned char sha1[20];
 282                 int len = strlen(de->d_name);
 283
 284                 switch (len) {
 285                 case 2:
 286                         if (de->d_name[1] != '.')
 287                                 break;
 288                 case 1:
 289                         if (de->d_name[0] != '.')
 290                                 break;
 291                         continue;
 292                 case 38:
 293                         sprintf(name, "%02x", i);
 294                         memcpy(name+2, de->d_name, len+1);
 295                         if (get_sha1_hex(name, sha1) < 0)
 296                                 break;
 297                         add_sha1_list(sha1, de->d_ino);
 298                         continue;
 299                 }
 300                 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 301         }
 302         closedir(dir);
 303         return 0;
 304 }
 305
 306 static int read_sha1_reference(const char *path)
 307 {
 308         char hexname[60];
 309         unsigned char sha1[20];
 310         int fd = open(path, O_RDONLY), len;
 311         struct object *obj;
 312
 313         if (fd < 0)
 314                 return -1;
 315
 316         len = read(fd, hexname, sizeof(hexname));
 317         close(fd);
 318         if (len < 40)
 319                 return -1;
 320
 321         if (get_sha1_hex(hexname, sha1) < 0)
 322                 return -1;
 323
 324         obj = lookup_object(sha1);
 325         if (!obj) {
 326                 if (!standalone && has_sha1_file(sha1))
 327                         return 0; /* it is in pack */
 328                 return error("%s: invalid sha1 pointer %.40s", path, hexname);
 329         }
 330
 331         obj->used = 1;
 332         mark_reachable(obj, REACHABLE);
 333         return 0;
 334 }
 335
 336 static int find_file_objects(const char *base, const char *name)
 337 {
 338         int baselen = strlen(base);
 339         int namelen = strlen(name);
 340         char *path = xmalloc(baselen + namelen + 2);
 341         struct stat st;
 342
 343         memcpy(path, base, baselen);
 344         path[baselen] = '/';
 345         memcpy(path + baselen + 1, name, namelen+1);
 346         if (stat(path, &st) < 0)
 347                 return 0;
 348
 349         /*
 350          * Recurse into directories
 351          */
 352         if (S_ISDIR(st.st_mode)) {
 353                 int count = 0;
 354                 DIR *dir = opendir(path);
 355                 if (dir) {
 356                         struct dirent *de;
 357                         while ((de = readdir(dir)) != NULL) {
 358                                 if (de->d_name[0] == '.')
 359                                         continue;
 360                                 count += find_file_objects(path, de->d_name);
 361                         }
 362                         closedir(dir);
 363                 }
 364                 return count;
 365         }
 366         if (S_ISREG(st.st_mode))
 367                 return read_sha1_reference(path) == 0;
 368         return 0;
 369 }
 370
 371 static void get_default_heads(void)
 372 {
 373         char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
 374         int count = find_file_objects(git_dir, "refs");
 375         if (!count)
 376                 die("No default references");
 377 }
 378
 379 static void fsck_object_dir(const char *path)
 380 {
 381         int i;
 382         for (i = 0; i < 256; i++) {
 383                 static char dir[4096];
 384                 sprintf(dir, "%s/%02x", path, i);
 385                 fsck_dir(i, dir);
 386         }
 387         fsck_sha1_list();
 388 }
 389
 390 int main(int argc, char **argv)
 391 {
 392         int i, heads;
 393
 394         for (i = 1; i < argc; i++) {
 395                 const char *arg = argv[i];
 396
 397                 if (!strcmp(arg, "--unreachable")) {
 398                         show_unreachable = 1;
 399                         continue;
 400                 }
 401                 if (!strcmp(arg, "--tags")) {
 402                         show_tags = 1;
 403                         continue;
 404                 }
 405                 if (!strcmp(arg, "--root")) {
 406                         show_root = 1;
 407                         continue;
 408                 }
 409                 if (!strcmp(arg, "--cache")) {
 410                         keep_cache_objects = 1;
 411                         continue;
 412                 }
 413                 if (!strcmp(arg, "--standalone")) {
 414                         standalone = 1;
 415                         continue;
 416                 }
 417                 if (!strcmp(arg, "--full")) {
 418                         check_full = 1;
 419                         continue;
 420                 }
 421                 if (*arg == '-')
 422                         usage("git-fsck-cache [--tags] [[--unreachable] [--cache] [--standalone | --full] <head-sha1>*]");
 423         }
 424
 425         if (standalone && check_full)
 426                 die("Only one of --standalone or --full can be used.");
 427         if (standalone)
 428                 unsetenv("GIT_ALTERNATE_OBJECT_DIRECTORIES");
 429
 430         fsck_object_dir(get_object_directory());
 431         if (check_full) {
 432                 int j;
 433                 struct packed_git *p;
 434                 prepare_alt_odb();
 435                 for (j = 0; alt_odb[j].base; j++) {
 436                         alt_odb[j].name[-1] = 0; /* was slash */
 437                         fsck_object_dir(alt_odb[j].base);
 438                         alt_odb[j].name[-1] = '/';
 439                 }
 440                 prepare_packed_git();
 441                 for (p = packed_git; p; p = p->next)
 442                         /* verify gives error messages itself */
 443                         verify_pack(p);
 444
 445                 for (p = packed_git; p; p = p->next) {
 446                         int num = num_packed_objects(p);
 447                         for (i = 0; i < num; i++) {
 448                                 unsigned char sha1[20];
 449                                 nth_packed_object_sha1(p, i, sha1);
 450                                 if (fsck_sha1(sha1) < 0)
 451                                         fprintf(stderr, "bad sha1 entry '%s'\n", sha1_to_hex(sha1));
 452
 453                         }
 454                 }
 455         }
 456
 457         heads = 0;
 458         for (i = 1; i < argc; i++) {
 459                 const char *arg = argv[i];
 460
 461                 if (*arg == '-')
 462                         continue;
 463
 464                 if (!get_sha1(arg, head_sha1)) {
 465                         struct object *obj = lookup_object(head_sha1);
 466
 467                         /* Error is printed by lookup_object(). */
 468                         if (!obj)
 469                                 continue;
 470
 471                         obj->used = 1;
 472                         mark_reachable(obj, REACHABLE);
 473                         heads++;
 474                         continue;
 475                 }
 476                 error("expected sha1, got %s", arg);
 477         }
 478
 479         /*
 480          * If we've not been given any explicit head information, do the
 481          * default ones from .git/refs. We also consider the index file
 482          * in this case (ie this implies --cache).
 483          */
 484         if (!heads) {
 485                 get_default_heads();
 486                 keep_cache_objects = 1;
 487         }
 488
 489         if (keep_cache_objects) {
 490                 int i;
 491                 read_cache();
 492                 for (i = 0; i < active_nr; i++) {
 493                         struct blob *blob = lookup_blob(active_cache[i]->sha1);
 494                         struct object *obj;
 495                         if (!blob)
 496                                 continue;
 497                         obj = &blob->object;
 498                         obj->used = 1;
 499                         mark_reachable(obj, REACHABLE);
 500                 }
 501         }
 502
 503         check_connectivity();
 504         return 0;
 505 }