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
  10 #define REACHABLE 0x0001
  11
  12 static int show_root = 0;
  13 static int show_tags = 0;
  14 static int show_unreachable = 0;
  15 static int keep_cache_objects = 0;
  16 static unsigned char head_sha1[20];
  17
  18 static void check_connectivity(void)
  19 {
  20         int i;
  21
  22         /* Look up all the requirements, warn about missing objects.. */
  23         for (i = 0; i < nr_objs; i++) {
  24                 struct object *obj = objs[i];
  25                 struct object_list *refs;
  26
  27                 if (!obj->parsed) {
  28                         printf("missing %s %s\n",
  29                                obj->type, sha1_to_hex(obj->sha1));
  30                         continue;
  31                 }
  32
  33                 for (refs = obj->refs; refs; refs = refs->next) {
  34                         if (refs->item->parsed)
  35                                 continue;
  36                         printf("broken link from %7s %s\n",
  37                                obj->type, sha1_to_hex(obj->sha1));
  38                         printf("              to %7s %s\n",
  39                                refs->item->type, sha1_to_hex(refs->item->sha1));
  40                 }
  41
  42                 if (show_unreachable && !(obj->flags & REACHABLE)) {
  43                         printf("unreachable %s %s\n",
  44                                obj->type, sha1_to_hex(obj->sha1));
  45                         continue;
  46                 }
  47
  48                 if (!obj->used) {
  49                         printf("dangling %s %s\n", obj->type,
  50                                sha1_to_hex(obj->sha1));
  51                 }
  52         }
  53 }
  54
  55 /*
  56  * The entries in a tree are ordered in the _path_ order,
  57  * which means that a directory entry is ordered by adding
  58  * a slash to the end of it.
  59  *
  60  * So a directory called "a" is ordered _after_ a file
  61  * called "a.c", because "a/" sorts after "a.c".
  62  */
  63 #define TREE_UNORDERED (-1)
  64 #define TREE_HAS_DUPS  (-2)
  65
  66 static int verify_ordered(struct tree_entry_list *a, struct tree_entry_list *b)
  67 {
  68         int len1 = strlen(a->name);
  69         int len2 = strlen(b->name);
  70         int len = len1 < len2 ? len1 : len2;
  71         unsigned char c1, c2;
  72         int cmp;
  73
  74         cmp = memcmp(a->name, b->name, len);
  75         if (cmp < 0)
  76                 return 0;
  77         if (cmp > 0)
  78                 return TREE_UNORDERED;
  79
  80         /*
  81          * Ok, the first <len> characters are the same.
  82          * Now we need to order the next one, but turn
  83          * a '\0' into a '/' for a directory entry.
  84          */
  85         c1 = a->name[len];
  86         c2 = b->name[len];
  87         if (!c1 && !c2)
  88                 /*
  89                  * git-write-tree used to write out a nonsense tree that has
  90                  * entries with the same name, one blob and one tree.  Make
  91                  * sure we do not have duplicate entries.
  92                  */
  93                 return TREE_HAS_DUPS;
  94         if (!c1 && a->directory)
  95                 c1 = '/';
  96         if (!c2 && b->directory)
  97                 c2 = '/';
  98         return c1 < c2 ? 0 : TREE_UNORDERED;
  99 }
 100
 101 static int fsck_tree(struct tree *item)
 102 {
 103         int has_full_path = 0;
 104         struct tree_entry_list *entry, *last;
 105
 106         last = NULL;
 107         for (entry = item->entries; entry; entry = entry->next) {
 108                 if (strchr(entry->name, '/'))
 109                         has_full_path = 1;
 110
 111                 switch (entry->mode) {
 112                 /*
 113                  * Standard modes..
 114                  */
 115                 case S_IFREG | 0755:
 116                 case S_IFREG | 0644:
 117                 case S_IFLNK:
 118                 case S_IFDIR:
 119                         break;
 120                 /*
 121                  * This is nonstandard, but we had a few of these
 122                  * early on when we honored the full set of mode
 123                  * bits..
 124                  */
 125                 case S_IFREG | 0664:
 126                         break;
 127                 default:
 128                         printf("tree %s has entry %o %s\n",
 129                                 sha1_to_hex(item->object.sha1),
 130                                 entry->mode, entry->name);
 131                 }
 132
 133                 if (last) {
 134                         switch (verify_ordered(last, entry)) {
 135                         case TREE_UNORDERED:
 136                                 fprintf(stderr, "tree %s not ordered\n",
 137                                         sha1_to_hex(item->object.sha1));
 138                                 return -1;
 139                         case TREE_HAS_DUPS:
 140                                 fprintf(stderr, "tree %s has duplicate entries for '%s'\n",
 141                                         sha1_to_hex(item->object.sha1),
 142                                         entry->name);
 143                                 return -1;
 144                         default:
 145                                 break;
 146                         }
 147                 }
 148
 149                 last = entry;
 150         }
 151
 152         if (has_full_path) {
 153                 fprintf(stderr, "warning: git-fsck-cache: tree %s "
 154                         "has full pathnames in it\n",
 155                         sha1_to_hex(item->object.sha1));
 156         }
 157
 158         return 0;
 159 }
 160
 161 static int fsck_commit(struct commit *commit)
 162 {
 163         free(commit->buffer);
 164         commit->buffer = NULL;
 165         if (!commit->tree)
 166                 return -1;
 167         if (!commit->parents && show_root)
 168                 printf("root %s\n", sha1_to_hex(commit->object.sha1));
 169         if (!commit->date)
 170                 printf("bad commit date in %s\n",
 171                        sha1_to_hex(commit->object.sha1));
 172         return 0;
 173 }
 174
 175 static int fsck_tag(struct tag *tag)
 176 {
 177         struct object *tagged = tag->tagged;
 178
 179         if (!tagged) {
 180                 printf("bad object in tag %s\n", sha1_to_hex(tag->object.sha1));
 181                 return -1;
 182         }
 183         if (!show_tags)
 184                 return 0;
 185
 186         printf("tagged %s %s", tagged->type, sha1_to_hex(tagged->sha1));
 187         printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
 188         return 0;
 189 }
 190
 191 static int fsck_sha1(unsigned char *sha1)
 192 {
 193         struct object *obj = parse_object(sha1);
 194         if (!obj)
 195                 return -1;
 196         if (obj->type == blob_type)
 197                 return 0;
 198         if (obj->type == tree_type)
 199                 return fsck_tree((struct tree *) obj);
 200         if (obj->type == commit_type)
 201                 return fsck_commit((struct commit *) obj);
 202         if (obj->type == tag_type)
 203                 return fsck_tag((struct tag *) obj);
 204         return -1;
 205 }
 206
 207 /*
 208  * This is the sorting chunk size: make it reasonably
 209  * big so that we can sort well..
 210  */
 211 #define MAX_SHA1_ENTRIES (1024)
 212
 213 struct sha1_entry {
 214         unsigned long ino;
 215         unsigned char sha1[20];
 216 };
 217
 218 static struct {
 219         unsigned long nr;
 220         struct sha1_entry *entry[MAX_SHA1_ENTRIES];
 221 } sha1_list;
 222
 223 static int ino_compare(const void *_a, const void *_b)
 224 {
 225         const struct sha1_entry *a = _a, *b = _b;
 226         unsigned long ino1 = a->ino, ino2 = b->ino;
 227         return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
 228 }
 229
 230 static void fsck_sha1_list(void)
 231 {
 232         int i, nr = sha1_list.nr;
 233
 234         qsort(sha1_list.entry, nr, sizeof(struct sha1_entry *), ino_compare);
 235         for (i = 0; i < nr; i++) {
 236                 struct sha1_entry *entry = sha1_list.entry[i];
 237                 unsigned char *sha1 = entry->sha1;
 238
 239                 sha1_list.entry[i] = NULL;
 240                 if (fsck_sha1(sha1) < 0)
 241                         fprintf(stderr, "bad sha1 entry '%s'\n", sha1_to_hex(sha1));
 242                 free(entry);
 243         }
 244         sha1_list.nr = 0;
 245 }
 246
 247 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
 248 {
 249         struct sha1_entry *entry = xmalloc(sizeof(*entry));
 250         int nr;
 251
 252         entry->ino = ino;
 253         memcpy(entry->sha1, sha1, 20);
 254         nr = sha1_list.nr;
 255         if (nr == MAX_SHA1_ENTRIES) {
 256                 fsck_sha1_list();
 257                 nr = 0;
 258         }
 259         sha1_list.entry[nr] = entry;
 260         sha1_list.nr = ++nr;
 261 }
 262
 263 static int fsck_dir(int i, char *path)
 264 {
 265         DIR *dir = opendir(path);
 266         struct dirent *de;
 267
 268         if (!dir) {
 269                 return error("missing sha1 directory '%s'", path);
 270         }
 271
 272         while ((de = readdir(dir)) != NULL) {
 273                 char name[100];
 274                 unsigned char sha1[20];
 275                 int len = strlen(de->d_name);
 276
 277                 switch (len) {
 278                 case 2:
 279                         if (de->d_name[1] != '.')
 280                                 break;
 281                 case 1:
 282                         if (de->d_name[0] != '.')
 283                                 break;
 284                         continue;
 285                 case 38:
 286                         sprintf(name, "%02x", i);
 287                         memcpy(name+2, de->d_name, len+1);
 288                         if (get_sha1_hex(name, sha1) < 0)
 289                                 break;
 290                         add_sha1_list(sha1, de->d_ino);
 291                         continue;
 292                 }
 293                 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 294         }
 295         closedir(dir);
 296         return 0;
 297 }
 298
 299 static int read_sha1_reference(const char *path)
 300 {
 301         char hexname[60];
 302         unsigned char sha1[20];
 303         int fd = open(path, O_RDONLY), len;
 304         struct object *obj;
 305
 306         if (fd < 0)
 307                 return -1;
 308
 309         len = read(fd, hexname, sizeof(hexname));
 310         close(fd);
 311         if (len < 40)
 312                 return -1;
 313
 314         if (get_sha1_hex(hexname, sha1) < 0)
 315                 return -1;
 316
 317         obj = lookup_object(sha1);
 318         if (!obj)
 319                 return error("%s: invalid sha1 pointer %.40s", path, hexname);
 320
 321         obj->used = 1;
 322         mark_reachable(obj, REACHABLE);
 323         return 0;
 324 }
 325
 326 static int find_file_objects(const char *base, const char *name)
 327 {
 328         int baselen = strlen(base);
 329         int namelen = strlen(name);
 330         char *path = xmalloc(baselen + namelen + 2);
 331         struct stat st;
 332
 333         memcpy(path, base, baselen);
 334         path[baselen] = '/';
 335         memcpy(path + baselen + 1, name, namelen+1);
 336         if (stat(path, &st) < 0)
 337                 return 0;
 338
 339         /*
 340          * Recurse into directories
 341          */
 342         if (S_ISDIR(st.st_mode)) {
 343                 int count = 0;
 344                 DIR *dir = opendir(path);
 345                 if (dir) {
 346                         struct dirent *de;
 347                         while ((de = readdir(dir)) != NULL) {
 348                                 if (de->d_name[0] == '.')
 349                                         continue;
 350                                 count += find_file_objects(path, de->d_name);
 351                         }
 352                         closedir(dir);
 353                 }
 354                 return count;
 355         }
 356         if (S_ISREG(st.st_mode))
 357                 return read_sha1_reference(path) == 0;
 358         return 0;
 359 }
 360
 361 static void get_default_heads(void)
 362 {
 363         char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
 364         int count = find_file_objects(git_dir, "refs");
 365         if (!count)
 366                 die("No default references");
 367 }
 368
 369 int main(int argc, char **argv)
 370 {
 371         int i, heads;
 372         char *sha1_dir;
 373
 374         for (i = 1; i < argc; i++) {
 375                 const char *arg = argv[i];
 376
 377                 if (!strcmp(arg, "--unreachable")) {
 378                         show_unreachable = 1;
 379                         continue;
 380                 }
 381                 if (!strcmp(arg, "--tags")) {
 382                         show_tags = 1;
 383                         continue;
 384                 }
 385                 if (!strcmp(arg, "--root")) {
 386                         show_root = 1;
 387                         continue;
 388                 }
 389                 if (!strcmp(arg, "--cache")) {
 390                         keep_cache_objects = 1;
 391                         continue;
 392                 }
 393                 if (*arg == '-')
 394                         usage("git-fsck-cache [--tags] [[--unreachable] [--cache] <head-sha1>*]");
 395         }
 396
 397         sha1_dir = get_object_directory();
 398         for (i = 0; i < 256; i++) {
 399                 static char dir[4096];
 400                 sprintf(dir, "%s/%02x", sha1_dir, i);
 401                 fsck_dir(i, dir);
 402         }
 403         fsck_sha1_list();
 404
 405         heads = 0;
 406         for (i = 1; i < argc; i++) {
 407                 const char *arg = argv[i];
 408
 409                 if (*arg == '-')
 410                         continue;
 411
 412                 if (!get_sha1(arg, head_sha1)) {
 413                         struct object *obj = lookup_object(head_sha1);
 414
 415                         /* Error is printed by lookup_object(). */
 416                         if (!obj)
 417                                 continue;
 418
 419                         obj->used = 1;
 420                         mark_reachable(obj, REACHABLE);
 421                         heads++;
 422                         continue;
 423                 }
 424                 error("expected sha1, got %s", arg);
 425         }
 426
 427         /*
 428          * If we've not been given any explicit head information, do the
 429          * default ones from .git/refs. We also consider the index file
 430          * in this case (ie this implies --cache).
 431          */
 432         if (!heads) {
 433                 get_default_heads();
 434                 keep_cache_objects = 1;
 435         }
 436
 437         if (keep_cache_objects) {
 438                 int i;
 439                 read_cache();
 440                 for (i = 0; i < active_nr; i++) {
 441                         struct blob *blob = lookup_blob(active_cache[i]->sha1);
 442                         struct object *obj;
 443                         if (!blob)
 444                                 continue;
 445                         obj = &blob->object;
 446                         obj->used = 1;
 447                         mark_reachable(obj, REACHABLE);
 448                 }
 449         }
 450
 451         check_connectivity();
 452         return 0;
 453 }