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
  41         status = lstat(path, &st);
  42         if (status < 0 || S_ISDIR(st.st_mode)) {
  43                 /* When we used to have "path" and now we want to add
  44                  * "path/file", we need a way to remove "path" before
  45                  * being able to add "path/file".  However,
  46                  * "git-update-index --remove path" would not work.
  47                  * --force-remove can be used but this is more user
  48                  * friendly, especially since we can do the opposite
  49                  * case just fine without --force-remove.
  50                  */
  51                 if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
  52                         if (allow_remove) {
  53                                 if (remove_file_from_cache(path))
  54                                         return error("%s: cannot remove from the index",
  55                                                      path);
  56                                 else
  57                                         return 0;
  58                         } else if (status < 0) {
  59                                 return error("%s: does not exist and --remove not passed",
  60                                              path);
  61                         }
  62                 }
  63                 if (0 == status)
  64                         return error("%s: is a directory - add files inside instead",
  65                                      path);
  66                 else
  67                         return error("lstat(\"%s\"): %s", path,
  68                                      strerror(errno));
  69         }
  70
  71         namelen = strlen(path);
  72         size = cache_entry_size(namelen);
  73         ce = xmalloc(size);
  74         memset(ce, 0, size);
  75         memcpy(ce->name, path, namelen);
  76         fill_stat_cache_info(ce, &st);
  77
  78         ce->ce_mode = create_ce_mode(st.st_mode);
  79         if (!trust_executable_bit) {
  80                 /* If there is an existing entry, pick the mode bits
  81                  * from it.
  82                  */
  83                 int pos = cache_name_pos(path, namelen);
  84                 if (0 <= pos)
  85                         ce->ce_mode = active_cache[pos]->ce_mode;
  86         }
  87         ce->ce_flags = htons(namelen);
  88
  89         if (index_path(ce->sha1, path, &st, !info_only))
  90                 return -1;
  91         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
  92         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
  93         if (add_cache_entry(ce, option))
  94                 return error("%s: cannot add to the index - missing --add option?",
  95                              path);
  96         return 0;
  97 }
  98
  99 /*
 100  * "refresh" does not calculate a new sha1 file or bring the
 101  * cache up-to-date for mode/content changes. But what it
 102  * _does_ do is to "re-match" the stat information of a file
 103  * with the cache, so that you can refresh the cache for a
 104  * file that hasn't been changed but where the stat entry is
 105  * out of date.
 106  *
 107  * For example, you'd want to do this after doing a "git-read-tree",
 108  * to link up the stat cache details with the proper files.
 109  */
 110 static struct cache_entry *refresh_entry(struct cache_entry *ce)
 111 {
 112         struct stat st;
 113         struct cache_entry *updated;
 114         int changed, size;
 115
 116         if (lstat(ce->name, &st) < 0)
 117                 return ERR_PTR(-errno);
 118
 119         changed = ce_match_stat(ce, &st);
 120         if (!changed)
 121                 return NULL;
 122
 123         if (ce_modified(ce, &st))
 124                 return ERR_PTR(-EINVAL);
 125
 126         size = ce_size(ce);
 127         updated = xmalloc(size);
 128         memcpy(updated, ce, size);
 129         fill_stat_cache_info(updated, &st);
 130         return updated;
 131 }
 132
 133 static int refresh_cache(void)
 134 {
 135         int i;
 136         int has_errors = 0;
 137
 138         for (i = 0; i < active_nr; i++) {
 139                 struct cache_entry *ce, *new;
 140                 ce = active_cache[i];
 141                 if (ce_stage(ce)) {
 142                         while ((i < active_nr) &&
 143                                ! strcmp(active_cache[i]->name, ce->name))
 144                                 i++;
 145                         i--;
 146                         if (allow_unmerged)
 147                                 continue;
 148                         printf("%s: needs merge\n", ce->name);
 149                         has_errors = 1;
 150                         continue;
 151                 }
 152
 153                 new = refresh_entry(ce);
 154                 if (!new)
 155                         continue;
 156                 if (IS_ERR(new)) {
 157                         if (not_new && PTR_ERR(new) == -ENOENT)
 158                                 continue;
 159                         if (quiet)
 160                                 continue;
 161                         printf("%s: needs update\n", ce->name);
 162                         has_errors = 1;
 163                         continue;
 164                 }
 165                 active_cache_changed = 1;
 166                 /* You can NOT just free active_cache[i] here, since it
 167                  * might not be necessarily malloc()ed but can also come
 168                  * from mmap(). */
 169                 active_cache[i] = new;
 170         }
 171         return has_errors;
 172 }
 173
 174 /*
 175  * We fundamentally don't like some paths: we don't want
 176  * dot or dot-dot anywhere, and for obvious reasons don't
 177  * want to recurse into ".git" either.
 178  *
 179  * Also, we don't want double slashes or slashes at the
 180  * end that can make pathnames ambiguous.
 181  */
 182 static int verify_dotfile(const char *rest)
 183 {
 184         /*
 185          * The first character was '.', but that
 186          * has already been discarded, we now test
 187          * the rest.
 188          */
 189         switch (*rest) {
 190         /* "." is not allowed */
 191         case '\0': case '/':
 192                 return 0;
 193
 194         /*
 195          * ".git" followed by  NUL or slash is bad. This
 196          * shares the path end test with the ".." case.
 197          */
 198         case 'g':
 199                 if (rest[1] != 'i')
 200                         break;
 201                 if (rest[2] != 't')
 202                         break;
 203                 rest += 2;
 204         /* fallthrough */
 205         case '.':
 206                 if (rest[1] == '\0' || rest[1] == '/')
 207                         return 0;
 208         }
 209         return 1;
 210 }
 211
 212 static int verify_path(const char *path)
 213 {
 214         char c;
 215
 216         goto inside;
 217         for (;;) {
 218                 if (!c)
 219                         return 1;
 220                 if (c == '/') {
 221 inside:
 222                         c = *path++;
 223                         switch (c) {
 224                         default:
 225                                 continue;
 226                         case '/': case '\0':
 227                                 break;
 228                         case '.':
 229                                 if (verify_dotfile(path))
 230                                         continue;
 231                         }
 232                         return 0;
 233                 }
 234                 c = *path++;
 235         }
 236 }
 237
 238 static int add_cacheinfo(const char *arg1, const char *arg2, const char *arg3)
 239 {
 240         int size, len, option;
 241         unsigned int mode;
 242         unsigned char sha1[20];
 243         struct cache_entry *ce;
 244
 245         if (sscanf(arg1, "%o", &mode) != 1)
 246                 return -1;
 247         if (get_sha1_hex(arg2, sha1))
 248                 return -1;
 249         if (!verify_path(arg3))
 250                 return -1;
 251
 252         len = strlen(arg3);
 253         size = cache_entry_size(len);
 254         ce = xmalloc(size);
 255         memset(ce, 0, size);
 256
 257         memcpy(ce->sha1, sha1, 20);
 258         memcpy(ce->name, arg3, len);
 259         ce->ce_flags = htons(len);
 260         ce->ce_mode = create_ce_mode(mode);
 261         option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
 262         option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
 263         return add_cache_entry(ce, option);
 264 }
 265
 266 static int chmod_path(int flip, const char *path)
 267 {
 268         int pos;
 269         struct cache_entry *ce;
 270         unsigned int mode;
 271
 272         pos = cache_name_pos(path, strlen(path));
 273         if (pos < 0)
 274                 return -1;
 275         ce = active_cache[pos];
 276         mode = ntohl(ce->ce_mode);
 277         if (!S_ISREG(mode))
 278                 return -1;
 279         switch (flip) {
 280         case '+':
 281                 ce->ce_mode |= htonl(0111); break;
 282         case '-':
 283                 ce->ce_mode &= htonl(~0111); break;
 284         default:
 285                 return -1;
 286         }
 287         active_cache_changed = 1;
 288         return 0;
 289 }
 290
 291 static struct cache_file cache_file;
 292
 293 static void update_one(const char *path, const char *prefix, int prefix_length)
 294 {
 295         const char *p = prefix_path(prefix, prefix_length, path);
 296         if (!verify_path(p)) {
 297                 fprintf(stderr, "Ignoring path %s\n", path);
 298                 return;
 299         }
 300         if (force_remove) {
 301                 if (remove_file_from_cache(p))
 302                         die("git-update-index: unable to remove %s", path);
 303                 return;
 304         }
 305         if (add_file_to_cache(p))
 306                 die("Unable to process file %s", path);
 307 }
 308
 309 static void read_index_info(int line_termination)
 310 {
 311         struct strbuf buf;
 312         strbuf_init(&buf);
 313         while (1) {
 314                 char *ptr;
 315                 unsigned char sha1[20];
 316                 unsigned int mode;
 317
 318                 read_line(&buf, stdin, line_termination);
 319                 if (buf.eof)
 320                         break;
 321
 322                 mode = strtoul(buf.buf, &ptr, 8);
 323                 if (ptr == buf.buf || *ptr != ' ' ||
 324                     get_sha1_hex(ptr + 1, sha1) ||
 325                     ptr[41] != '\t')
 326                         goto bad_line;
 327
 328                 ptr += 42;
 329                 if (!verify_path(ptr)) {
 330                         fprintf(stderr, "Ignoring path %s\n", ptr);
 331                         continue;
 332                 }
 333
 334                 if (!mode) {
 335                         /* mode == 0 means there is no such path -- remove */
 336                         if (remove_file_from_cache(ptr))
 337                                 die("git-update-index: unable to remove %s",
 338                                     ptr);
 339                 }
 340                 else {
 341                         /* mode ' ' sha1 '\t' name
 342                          * ptr[-1] points at tab,
 343                          * ptr[-41] is at the beginning of sha1
 344                          */
 345                         ptr[-42] = ptr[-1] = 0;
 346                         if (add_cacheinfo(buf.buf, ptr-41, ptr))
 347                                 die("git-update-index: unable to update %s",
 348                                     ptr);
 349                 }
 350                 continue;
 351
 352         bad_line:
 353                 die("malformed index info %s", buf.buf);
 354         }
 355 }
 356
 357 int main(int argc, const char **argv)
 358 {
 359         int i, newfd, entries, has_errors = 0, line_termination = '\n';
 360         int allow_options = 1;
 361         int read_from_stdin = 0;
 362         const char *prefix = setup_git_directory();
 363         int prefix_length = prefix ? strlen(prefix) : 0;
 364
 365         git_config(git_default_config);
 366
 367         newfd = hold_index_file_for_update(&cache_file, get_index_file());
 368         if (newfd < 0)
 369                 die("unable to create new cachefile");
 370
 371         entries = read_cache();
 372         if (entries < 0)
 373                 die("cache corrupted");
 374
 375         for (i = 1 ; i < argc; i++) {
 376                 const char *path = argv[i];
 377
 378                 if (allow_options && *path == '-') {
 379                         if (!strcmp(path, "--")) {
 380                                 allow_options = 0;
 381                                 continue;
 382                         }
 383                         if (!strcmp(path, "-q")) {
 384                                 quiet = 1;
 385                                 continue;
 386                         }
 387                         if (!strcmp(path, "--add")) {
 388                                 allow_add = 1;
 389                                 continue;
 390                         }
 391                         if (!strcmp(path, "--replace")) {
 392                                 allow_replace = 1;
 393                                 continue;
 394                         }
 395                         if (!strcmp(path, "--remove")) {
 396                                 allow_remove = 1;
 397                                 continue;
 398                         }
 399                         if (!strcmp(path, "--unmerged")) {
 400                                 allow_unmerged = 1;
 401                                 continue;
 402                         }
 403                         if (!strcmp(path, "--refresh")) {
 404                                 has_errors |= refresh_cache();
 405                                 continue;
 406                         }
 407                         if (!strcmp(path, "--cacheinfo")) {
 408                                 if (i+3 >= argc)
 409                                         die("git-update-index: --cacheinfo <mode> <sha1> <path>");
 410                                 if (add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
 411                                         die("git-update-index: --cacheinfo cannot add %s", argv[i+3]);
 412                                 i += 3;
 413                                 continue;
 414                         }
 415                         if (!strcmp(path, "--chmod=-x") ||
 416                             !strcmp(path, "--chmod=+x")) {
 417                                 if (argc <= i+1)
 418                                         die("git-update-index: %s <path>", path);
 419                                 if (chmod_path(path[8], argv[++i]))
 420                                         die("git-update-index: %s cannot chmod %s", path, argv[i]);
 421                                 continue;
 422                         }
 423                         if (!strcmp(path, "--info-only")) {
 424                                 info_only = 1;
 425                                 continue;
 426                         }
 427                         if (!strcmp(path, "--force-remove")) {
 428                                 force_remove = 1;
 429                                 continue;
 430                         }
 431                         if (!strcmp(path, "-z")) {
 432                                 line_termination = 0;
 433                                 continue;
 434                         }
 435                         if (!strcmp(path, "--stdin")) {
 436                                 if (i != argc - 1)
 437                                         die("--stdin must be at the end");
 438                                 read_from_stdin = 1;
 439                                 break;
 440                         }
 441                         if (!strcmp(path, "--index-info")) {
 442                                 allow_add = allow_replace = allow_remove = 1;
 443                                 read_index_info(line_termination);
 444                                 continue;
 445                         }
 446                         if (!strcmp(path, "--ignore-missing")) {
 447                                 not_new = 1;
 448                                 continue;
 449                         }
 450                         die("unknown option %s", path);
 451                 }
 452                 update_one(path, prefix, prefix_length);
 453         }
 454         if (read_from_stdin) {
 455                 struct strbuf buf;
 456                 strbuf_init(&buf);
 457                 while (1) {
 458                         read_line(&buf, stdin, line_termination);
 459                         if (buf.eof)
 460                                 break;
 461                         update_one(buf.buf, prefix, prefix_length);
 462                 }
 463         }
 464         if (active_cache_changed) {
 465                 if (write_cache(newfd, active_cache, active_nr) ||
 466                     commit_index_file(&cache_file))
 467                         die("Unable to write new cachefile");
 468         }
 469
 470         return has_errors ? 1 : 0;
 471 }