update-index.c

   1 /*
   2  * GIT - The information manager from hell
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  */
   6 #include "cache.h"
   7 #include "strbuf.h"
   8
   9 /*
  10  * Default to not allowing changes to the list of files. The
  11  * tool doesn't actually care, but this makes it harder to add
  12  * files to the revision control by mistake by doing something
  13  * like "git-update-index *" and suddenly having all the object
  14  * files be revision controlled.
  15  */
  16 static int allow_add = 0, allow_remove = 0, allow_replace = 0, allow_unmerged = 0, not_new = 0, quiet = 0, info_only = 0;
  17 static int force_remove;
  18
  19 /* Three functions to allow overloaded pointer return; see linux/err.h */
  20 static inline void *ERR_PTR(long error)
  21 {
  22         return (void *) error;
  23 }
  24
  25 static inline long PTR_ERR(const void *ptr)
  26 {
  27         return (long) ptr;
  28 }
  29
  30 static inline long IS_ERR(const void *ptr)
  31 {
  32         return (unsigned long)ptr > (unsigned long)-1000L;
  33 }
  34
  35 static int add_file_to_cache(const char *path)
  36 {
  37         int size, namelen, option, status;
  38         struct cache_entry *ce;
  39         struct stat st;
  40         int fd;
  41         char *target;
  42
  43         status = lstat(path, &st);
  44         if (status < 0 || S_ISDIR(st.st_mode)) {
  45                 /* When we used to have "path" and now we want to add
  46                  * "path/file", we need a way to remove "path" before
  47                  * being able to add "path/file".  However,
  48                  * "git-update-index --remove path" would not work.
  49                  * --force-remove can be used but this is more user
  50                  * friendly, especially since we can do the opposite
  51                  * case just fine without --force-remove.
  52                  */
  53                 if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
  54                         if (allow_remove) {
  55                                 if (remove_file_from_cache(path))
  56                                         return error("%s: cannot remove from the index",
  57                                                      path);
  58                                 else
  59                                         return 0;
  60                         } else if (status < 0) {
  61                                 return error("%s: does not exist and --remove not passed",
  62                                              path);
  63                         }
  64                 }
  65                 if (0 == status)
  66                         return error("%s: is a directory - add files inside instead",
  67                                      path);
  68                 else
  69                         return error("lstat(\"%s\"): %s", path,
  70                                      strerror(errno));
  71         }
  72         namelen = strlen(path);
  73         size = cache_entry_size(namelen);
  74         ce = xmalloc(size);
  75         memset(ce, 0, size);
  76         memcpy(ce->name, path, namelen);
  77         fill_stat_cache_info(ce, &st);
  78         ce->ce_mode = create_ce_mode(st.st_mode);
  79         ce->ce_flags = htons(namelen);
  80         switch (st.st_mode & S_IFMT) {
  81         case S_IFREG:
  82                 fd = open(path, O_RDONLY);
  83                 if (fd < 0)
  84                         return error("open(\"%s\"): %s", path, strerror(errno));
  85                 if (index_fd(ce->sha1, fd, &st, !info_only, NULL) < 0)
  86                         return error("%s: failed to insert into database", path);
  87                 break;
  88         case S_IFLNK:
  89                 target = xmalloc(st.st_size+1);
  90                 if (readlink(path, target, st.st_size+1) != st.st_size) {
  91                         char *errstr = strerror(errno);
  92                         free(target);
  93                         return error("readlink(\"%s\"): %s", path,
  94                                      errstr);
  95                 }
  96                 if (info_only) {
  97                         unsigned char hdr[50];
  98                         int hdrlen;
  99                         write_sha1_file_prepare(target, st.st_size, "blob",
 100                                                 ce->sha1, hdr, &hdrlen);
 101                 } else if (write_sha1_file(target, st.st_size, "blob", ce->sha1))
 102                         return error("%s: failed to insert into database", path);
 103                 free(target);
 104                 break;
 105         default:
 106                 return error("%s: unsupported file type", path);
 107         }
 108         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
 109         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
 110         if (add_cache_entry(ce, option))
 111                 return error("%s: cannot add to the index - missing --add option?",
 112                              path);
 113         return 0;
 114 }
 115
 116 /*
 117  * "refresh" does not calculate a new sha1 file or bring the
 118  * cache up-to-date for mode/content changes. But what it
 119  * _does_ do is to "re-match" the stat information of a file
 120  * with the cache, so that you can refresh the cache for a
 121  * file that hasn't been changed but where the stat entry is
 122  * out of date.
 123  *
 124  * For example, you'd want to do this after doing a "git-read-tree",
 125  * to link up the stat cache details with the proper files.
 126  */
 127 static struct cache_entry *refresh_entry(struct cache_entry *ce)
 128 {
 129         struct stat st;
 130         struct cache_entry *updated;
 131         int changed, size;
 132
 133         if (lstat(ce->name, &st) < 0)
 134                 return ERR_PTR(-errno);
 135
 136         changed = ce_match_stat(ce, &st);
 137         if (!changed)
 138                 return NULL;
 139
 140         if (ce_modified(ce, &st))
 141                 return ERR_PTR(-EINVAL);
 142
 143         size = ce_size(ce);
 144         updated = xmalloc(size);
 145         memcpy(updated, ce, size);
 146         fill_stat_cache_info(updated, &st);
 147         return updated;
 148 }
 149
 150 static int refresh_cache(void)
 151 {
 152         int i;
 153         int has_errors = 0;
 154
 155         for (i = 0; i < active_nr; i++) {
 156                 struct cache_entry *ce, *new;
 157                 ce = active_cache[i];
 158                 if (ce_stage(ce)) {
 159                         while ((i < active_nr) &&
 160                                ! strcmp(active_cache[i]->name, ce->name))
 161                                 i++;
 162                         i--;
 163                         if (allow_unmerged)
 164                                 continue;
 165                         printf("%s: needs merge\n", ce->name);
 166                         has_errors = 1;
 167                         continue;
 168                 }
 169
 170                 new = refresh_entry(ce);
 171                 if (!new)
 172                         continue;
 173                 if (IS_ERR(new)) {
 174                         if (not_new && PTR_ERR(new) == -ENOENT)
 175                                 continue;
 176                         if (quiet)
 177                                 continue;
 178                         printf("%s: needs update\n", ce->name);
 179                         has_errors = 1;
 180                         continue;
 181                 }
 182                 active_cache_changed = 1;
 183                 /* You can NOT just free active_cache[i] here, since it
 184                  * might not be necessarily malloc()ed but can also come
 185                  * from mmap(). */
 186                 active_cache[i] = new;
 187         }
 188         return has_errors;
 189 }
 190
 191 /*
 192  * We fundamentally don't like some paths: we don't want
 193  * dot or dot-dot anywhere, and for obvious reasons don't
 194  * want to recurse into ".git" either.
 195  *
 196  * Also, we don't want double slashes or slashes at the
 197  * end that can make pathnames ambiguous.
 198  */
 199 static int verify_dotfile(const char *rest)
 200 {
 201         /*
 202          * The first character was '.', but that
 203          * has already been discarded, we now test
 204          * the rest.
 205          */
 206         switch (*rest) {
 207         /* "." is not allowed */
 208         case '\0': case '/':
 209                 return 0;
 210
 211         /*
 212          * ".git" followed by  NUL or slash is bad. This
 213          * shares the path end test with the ".." case.
 214          */
 215         case 'g':
 216                 if (rest[1] != 'i')
 217                         break;
 218                 if (rest[2] != 't')
 219                         break;
 220                 rest += 2;
 221         /* fallthrough */
 222         case '.':
 223                 if (rest[1] == '\0' || rest[1] == '/')
 224                         return 0;
 225         }
 226         return 1;
 227 }
 228
 229 static int verify_path(const char *path)
 230 {
 231         char c;
 232
 233         goto inside;
 234         for (;;) {
 235                 if (!c)
 236                         return 1;
 237                 if (c == '/') {
 238 inside:
 239                         c = *path++;
 240                         switch (c) {
 241                         default:
 242                                 continue;
 243                         case '/': case '\0':
 244                                 break;
 245                         case '.':
 246                                 if (verify_dotfile(path))
 247                                         continue;
 248                         }
 249                         return 0;
 250                 }
 251                 c = *path++;
 252         }
 253 }
 254
 255 static int add_cacheinfo(const char *arg1, const char *arg2, const char *arg3)
 256 {
 257         int size, len, option;
 258         unsigned int mode;
 259         unsigned char sha1[20];
 260         struct cache_entry *ce;
 261
 262         if (sscanf(arg1, "%o", &mode) != 1)
 263                 return -1;
 264         if (get_sha1_hex(arg2, sha1))
 265                 return -1;
 266         if (!verify_path(arg3))
 267                 return -1;
 268
 269         len = strlen(arg3);
 270         size = cache_entry_size(len);
 271         ce = xmalloc(size);
 272         memset(ce, 0, size);
 273
 274         memcpy(ce->sha1, sha1, 20);
 275         memcpy(ce->name, arg3, len);
 276         ce->ce_flags = htons(len);
 277         ce->ce_mode = create_ce_mode(mode);
 278         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
 279         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
 280         return add_cache_entry(ce, option);
 281 }
 282
 283 static struct cache_file cache_file;
 284
 285
 286 static void update_one(const char *path, const char *prefix, int prefix_length)
 287 {
 288         const char *p = prefix_path(prefix, prefix_length, path);
 289         if (!verify_path(p)) {
 290                 fprintf(stderr, "Ignoring path %s\n", path);
 291                 return;
 292         }
 293         if (force_remove) {
 294                 if (remove_file_from_cache(p))
 295                         die("git-update-index: unable to remove %s", path);
 296                 return;
 297         }
 298         if (add_file_to_cache(p))
 299                 die("Unable to process file %s", path);
 300 }
 301
 302 int main(int argc, const char **argv)
 303 {
 304         int i, newfd, entries, has_errors = 0, line_termination = '\n';
 305         int allow_options = 1;
 306         int read_from_stdin = 0;
 307         const char *prefix = setup_git_directory();
 308         int prefix_length = prefix ? strlen(prefix) : 0;
 309
 310         newfd = hold_index_file_for_update(&cache_file, get_index_file());
 311         if (newfd < 0)
 312                 die("unable to create new cachefile");
 313
 314         entries = read_cache();
 315         if (entries < 0)
 316                 die("cache corrupted");
 317
 318         for (i = 1 ; i < argc; i++) {
 319                 const char *path = argv[i];
 320
 321                 if (allow_options && *path == '-') {
 322                         if (!strcmp(path, "--")) {
 323                                 allow_options = 0;
 324                                 continue;
 325                         }
 326                         if (!strcmp(path, "-q")) {
 327                                 quiet = 1;
 328                                 continue;
 329                         }
 330                         if (!strcmp(path, "--add")) {
 331                                 allow_add = 1;
 332                                 continue;
 333                         }
 334                         if (!strcmp(path, "--replace")) {
 335                                 allow_replace = 1;
 336                                 continue;
 337                         }
 338                         if (!strcmp(path, "--remove")) {
 339                                 allow_remove = 1;
 340                                 continue;
 341                         }
 342                         if (!strcmp(path, "--unmerged")) {
 343                                 allow_unmerged = 1;
 344                                 continue;
 345                         }
 346                         if (!strcmp(path, "--refresh")) {
 347                                 has_errors |= refresh_cache();
 348                                 continue;
 349                         }
 350                         if (!strcmp(path, "--cacheinfo")) {
 351                                 if (i+3 >= argc)
 352                                         die("git-update-index: --cacheinfo <mode> <sha1> <path>");
 353                                 if (add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
 354                                         die("git-update-index: --cacheinfo cannot add %s", argv[i+3]);
 355                                 i += 3;
 356                                 continue;
 357                         }
 358                         if (!strcmp(path, "--info-only")) {
 359                                 info_only = 1;
 360                                 continue;
 361                         }
 362                         if (!strcmp(path, "--force-remove")) {
 363                                 force_remove = 1;
 364                                 continue;
 365                         }
 366                         if (!strcmp(path, "-z")) {
 367                                 line_termination = 0;
 368                                 continue;
 369                         }
 370                         if (!strcmp(path, "--stdin")) {
 371                                 if (i != argc - 1)
 372                                         die("--stdin must be at the end");
 373                                 read_from_stdin = 1;
 374                                 break;
 375                         }
 376                         if (!strcmp(path, "--ignore-missing")) {
 377                                 not_new = 1;
 378                                 continue;
 379                         }
 380                         die("unknown option %s", path);
 381                 }
 382                 update_one(path, prefix, prefix_length);
 383         }
 384         if (read_from_stdin) {
 385                 struct strbuf buf;
 386                 strbuf_init(&buf);
 387                 while (1) {
 388                         read_line(&buf, stdin, line_termination);
 389                         if (buf.eof)
 390                                 break;
 391                         update_one(buf.buf, prefix, prefix_length);
 392                 }
 393         }
 394         if (write_cache(newfd, active_cache, active_nr) ||
 395             commit_index_file(&cache_file))
 396                 die("Unable to write new cachefile");
 397
 398         return has_errors ? 1 : 0;
 399 }