entry.con commit Merge branch 'rs/fsck-obj-leakfix' into maint (c3b931e)
   1#include "cache.h"
   2#include "blob.h"
   3#include "dir.h"
   4#include "streaming.h"
   5#include "submodule.h"
   6
   7static void create_directories(const char *path, int path_len,
   8                               const struct checkout *state)
   9{
  10        char *buf = xmallocz(path_len);
  11        int len = 0;
  12
  13        while (len < path_len) {
  14                do {
  15                        buf[len] = path[len];
  16                        len++;
  17                } while (len < path_len && path[len] != '/');
  18                if (len >= path_len)
  19                        break;
  20                buf[len] = 0;
  21
  22                /*
  23                 * For 'checkout-index --prefix=<dir>', <dir> is
  24                 * allowed to be a symlink to an existing directory,
  25                 * and we set 'state->base_dir_len' below, such that
  26                 * we test the path components of the prefix with the
  27                 * stat() function instead of the lstat() function.
  28                 */
  29                if (has_dirs_only_path(buf, len, state->base_dir_len))
  30                        continue; /* ok, it is already a directory. */
  31
  32                /*
  33                 * If this mkdir() would fail, it could be that there
  34                 * is already a symlink or something else exists
  35                 * there, therefore we then try to unlink it and try
  36                 * one more time to create the directory.
  37                 */
  38                if (mkdir(buf, 0777)) {
  39                        if (errno == EEXIST && state->force &&
  40                            !unlink_or_warn(buf) && !mkdir(buf, 0777))
  41                                continue;
  42                        die_errno("cannot create directory at '%s'", buf);
  43                }
  44        }
  45        free(buf);
  46}
  47
  48static void remove_subtree(struct strbuf *path)
  49{
  50        DIR *dir = opendir(path->buf);
  51        struct dirent *de;
  52        int origlen = path->len;
  53
  54        if (!dir)
  55                die_errno("cannot opendir '%s'", path->buf);
  56        while ((de = readdir(dir)) != NULL) {
  57                struct stat st;
  58
  59                if (is_dot_or_dotdot(de->d_name))
  60                        continue;
  61
  62                strbuf_addch(path, '/');
  63                strbuf_addstr(path, de->d_name);
  64                if (lstat(path->buf, &st))
  65                        die_errno("cannot lstat '%s'", path->buf);
  66                if (S_ISDIR(st.st_mode))
  67                        remove_subtree(path);
  68                else if (unlink(path->buf))
  69                        die_errno("cannot unlink '%s'", path->buf);
  70                strbuf_setlen(path, origlen);
  71        }
  72        closedir(dir);
  73        if (rmdir(path->buf))
  74                die_errno("cannot rmdir '%s'", path->buf);
  75}
  76
  77static int create_file(const char *path, unsigned int mode)
  78{
  79        mode = (mode & 0100) ? 0777 : 0666;
  80        return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
  81}
  82
  83static void *read_blob_entry(const struct cache_entry *ce, unsigned long *size)
  84{
  85        enum object_type type;
  86        void *new = read_sha1_file(ce->oid.hash, &type, size);
  87
  88        if (new) {
  89                if (type == OBJ_BLOB)
  90                        return new;
  91                free(new);
  92        }
  93        return NULL;
  94}
  95
  96static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
  97{
  98        int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
  99        if (to_tempfile) {
 100                xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
 101                          symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
 102                return mkstemp(path);
 103        } else {
 104                return create_file(path, !symlink ? ce->ce_mode : 0666);
 105        }
 106}
 107
 108static int fstat_output(int fd, const struct checkout *state, struct stat *st)
 109{
 110        /* use fstat() only when path == ce->name */
 111        if (fstat_is_reliable() &&
 112            state->refresh_cache && !state->base_dir_len) {
 113                fstat(fd, st);
 114                return 1;
 115        }
 116        return 0;
 117}
 118
 119static int streaming_write_entry(const struct cache_entry *ce, char *path,
 120                                 struct stream_filter *filter,
 121                                 const struct checkout *state, int to_tempfile,
 122                                 int *fstat_done, struct stat *statbuf)
 123{
 124        int result = 0;
 125        int fd;
 126
 127        fd = open_output_fd(path, ce, to_tempfile);
 128        if (fd < 0)
 129                return -1;
 130
 131        result |= stream_blob_to_fd(fd, &ce->oid, filter, 1);
 132        *fstat_done = fstat_output(fd, state, statbuf);
 133        result |= close(fd);
 134
 135        if (result)
 136                unlink(path);
 137        return result;
 138}
 139
 140void enable_delayed_checkout(struct checkout *state)
 141{
 142        if (!state->delayed_checkout) {
 143                state->delayed_checkout = xmalloc(sizeof(*state->delayed_checkout));
 144                state->delayed_checkout->state = CE_CAN_DELAY;
 145                string_list_init(&state->delayed_checkout->filters, 0);
 146                string_list_init(&state->delayed_checkout->paths, 0);
 147        }
 148}
 149
 150static int remove_available_paths(struct string_list_item *item, void *cb_data)
 151{
 152        struct string_list *available_paths = cb_data;
 153        struct string_list_item *available;
 154
 155        available = string_list_lookup(available_paths, item->string);
 156        if (available)
 157                available->util = (void *)item->string;
 158        return !available;
 159}
 160
 161int finish_delayed_checkout(struct checkout *state)
 162{
 163        int errs = 0;
 164        struct string_list_item *filter, *path;
 165        struct delayed_checkout *dco = state->delayed_checkout;
 166
 167        if (!state->delayed_checkout)
 168                return errs;
 169
 170        dco->state = CE_RETRY;
 171        while (dco->filters.nr > 0) {
 172                for_each_string_list_item(filter, &dco->filters) {
 173                        struct string_list available_paths = STRING_LIST_INIT_NODUP;
 174
 175                        if (!async_query_available_blobs(filter->string, &available_paths)) {
 176                                /* Filter reported an error */
 177                                errs = 1;
 178                                filter->string = "";
 179                                continue;
 180                        }
 181                        if (available_paths.nr <= 0) {
 182                                /*
 183                                 * Filter responded with no entries. That means
 184                                 * the filter is done and we can remove the
 185                                 * filter from the list (see
 186                                 * "string_list_remove_empty_items" call below).
 187                                 */
 188                                filter->string = "";
 189                                continue;
 190                        }
 191
 192                        /*
 193                         * In dco->paths we store a list of all delayed paths.
 194                         * The filter just send us a list of available paths.
 195                         * Remove them from the list.
 196                         */
 197                        filter_string_list(&dco->paths, 0,
 198                                &remove_available_paths, &available_paths);
 199
 200                        for_each_string_list_item(path, &available_paths) {
 201                                struct cache_entry* ce;
 202
 203                                if (!path->util) {
 204                                        error("external filter '%s' signaled that '%s' "
 205                                              "is now available although it has not been "
 206                                              "delayed earlier",
 207                                              filter->string, path->string);
 208                                        errs |= 1;
 209
 210                                        /*
 211                                         * Do not ask the filter for available blobs,
 212                                         * again, as the filter is likely buggy.
 213                                         */
 214                                        filter->string = "";
 215                                        continue;
 216                                }
 217                                ce = index_file_exists(state->istate, path->string,
 218                                                       strlen(path->string), 0);
 219                                errs |= (ce ? checkout_entry(ce, state, NULL) : 1);
 220                        }
 221                }
 222                string_list_remove_empty_items(&dco->filters, 0);
 223        }
 224        string_list_clear(&dco->filters, 0);
 225
 226        /* At this point we should not have any delayed paths anymore. */
 227        errs |= dco->paths.nr;
 228        for_each_string_list_item(path, &dco->paths) {
 229                error("'%s' was not filtered properly", path->string);
 230        }
 231        string_list_clear(&dco->paths, 0);
 232
 233        free(dco);
 234        state->delayed_checkout = NULL;
 235
 236        return errs;
 237}
 238
 239static int write_entry(struct cache_entry *ce,
 240                       char *path, const struct checkout *state, int to_tempfile)
 241{
 242        unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
 243        int fd, ret, fstat_done = 0;
 244        char *new;
 245        struct strbuf buf = STRBUF_INIT;
 246        unsigned long size;
 247        size_t wrote, newsize = 0;
 248        struct stat st;
 249        const struct submodule *sub;
 250
 251        if (ce_mode_s_ifmt == S_IFREG) {
 252                struct stream_filter *filter = get_stream_filter(ce->name,
 253                                                                 ce->oid.hash);
 254                if (filter &&
 255                    !streaming_write_entry(ce, path, filter,
 256                                           state, to_tempfile,
 257                                           &fstat_done, &st))
 258                        goto finish;
 259        }
 260
 261        switch (ce_mode_s_ifmt) {
 262        case S_IFREG:
 263        case S_IFLNK:
 264                new = read_blob_entry(ce, &size);
 265                if (!new)
 266                        return error("unable to read sha1 file of %s (%s)",
 267                                path, oid_to_hex(&ce->oid));
 268
 269                if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
 270                        ret = symlink(new, path);
 271                        free(new);
 272                        if (ret)
 273                                return error_errno("unable to create symlink %s",
 274                                                   path);
 275                        break;
 276                }
 277
 278                /*
 279                 * Convert from git internal format to working tree format
 280                 */
 281                if (ce_mode_s_ifmt == S_IFREG) {
 282                        struct delayed_checkout *dco = state->delayed_checkout;
 283                        if (dco && dco->state != CE_NO_DELAY) {
 284                                /* Do not send the blob in case of a retry. */
 285                                if (dco->state == CE_RETRY) {
 286                                        new = NULL;
 287                                        size = 0;
 288                                }
 289                                ret = async_convert_to_working_tree(
 290                                        ce->name, new, size, &buf, dco);
 291                                if (ret && string_list_has_string(&dco->paths, ce->name)) {
 292                                        free(new);
 293                                        goto finish;
 294                                }
 295                        } else
 296                                ret = convert_to_working_tree(
 297                                        ce->name, new, size, &buf);
 298
 299                        if (ret) {
 300                                free(new);
 301                                new = strbuf_detach(&buf, &newsize);
 302                                size = newsize;
 303                        }
 304                        /*
 305                         * No "else" here as errors from convert are OK at this
 306                         * point. If the error would have been fatal (e.g.
 307                         * filter is required), then we would have died already.
 308                         */
 309                }
 310
 311                fd = open_output_fd(path, ce, to_tempfile);
 312                if (fd < 0) {
 313                        free(new);
 314                        return error_errno("unable to create file %s", path);
 315                }
 316
 317                wrote = write_in_full(fd, new, size);
 318                if (!to_tempfile)
 319                        fstat_done = fstat_output(fd, state, &st);
 320                close(fd);
 321                free(new);
 322                if (wrote != size)
 323                        return error("unable to write file %s", path);
 324                break;
 325        case S_IFGITLINK:
 326                if (to_tempfile)
 327                        return error("cannot create temporary submodule %s", path);
 328                if (mkdir(path, 0777) < 0)
 329                        return error("cannot create submodule directory %s", path);
 330                sub = submodule_from_ce(ce);
 331                if (sub)
 332                        return submodule_move_head(ce->name,
 333                                NULL, oid_to_hex(&ce->oid),
 334                                state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 335                break;
 336        default:
 337                return error("unknown file mode for %s in index", path);
 338        }
 339
 340finish:
 341        if (state->refresh_cache) {
 342                assert(state->istate);
 343                if (!fstat_done)
 344                        lstat(ce->name, &st);
 345                fill_stat_cache_info(ce, &st);
 346                ce->ce_flags |= CE_UPDATE_IN_BASE;
 347                state->istate->cache_changed |= CE_ENTRY_CHANGED;
 348        }
 349        return 0;
 350}
 351
 352/*
 353 * This is like 'lstat()', except it refuses to follow symlinks
 354 * in the path, after skipping "skiplen".
 355 */
 356static int check_path(const char *path, int len, struct stat *st, int skiplen)
 357{
 358        const char *slash = path + len;
 359
 360        while (path < slash && *slash != '/')
 361                slash--;
 362        if (!has_dirs_only_path(path, slash - path, skiplen)) {
 363                errno = ENOENT;
 364                return -1;
 365        }
 366        return lstat(path, st);
 367}
 368
 369/*
 370 * Write the contents from ce out to the working tree.
 371 *
 372 * When topath[] is not NULL, instead of writing to the working tree
 373 * file named by ce, a temporary file is created by this function and
 374 * its name is returned in topath[], which must be able to hold at
 375 * least TEMPORARY_FILENAME_LENGTH bytes long.
 376 */
 377int checkout_entry(struct cache_entry *ce,
 378                   const struct checkout *state, char *topath)
 379{
 380        static struct strbuf path = STRBUF_INIT;
 381        struct stat st;
 382
 383        if (topath)
 384                return write_entry(ce, topath, state, 1);
 385
 386        strbuf_reset(&path);
 387        strbuf_add(&path, state->base_dir, state->base_dir_len);
 388        strbuf_add(&path, ce->name, ce_namelen(ce));
 389
 390        if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
 391                const struct submodule *sub;
 392                unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
 393                /*
 394                 * Needs to be checked before !changed returns early,
 395                 * as the possibly empty directory was not changed
 396                 */
 397                sub = submodule_from_ce(ce);
 398                if (sub) {
 399                        int err;
 400                        if (!is_submodule_populated_gently(ce->name, &err)) {
 401                                struct stat sb;
 402                                if (lstat(ce->name, &sb))
 403                                        die(_("could not stat file '%s'"), ce->name);
 404                                if (!(st.st_mode & S_IFDIR))
 405                                        unlink_or_warn(ce->name);
 406
 407                                return submodule_move_head(ce->name,
 408                                        NULL, oid_to_hex(&ce->oid), 0);
 409                        } else
 410                                return submodule_move_head(ce->name,
 411                                        "HEAD", oid_to_hex(&ce->oid),
 412                                        state->force ? SUBMODULE_MOVE_HEAD_FORCE : 0);
 413                }
 414
 415                if (!changed)
 416                        return 0;
 417                if (!state->force) {
 418                        if (!state->quiet)
 419                                fprintf(stderr,
 420                                        "%s already exists, no checkout\n",
 421                                        path.buf);
 422                        return -1;
 423                }
 424
 425                /*
 426                 * We unlink the old file, to get the new one with the
 427                 * right permissions (including umask, which is nasty
 428                 * to emulate by hand - much easier to let the system
 429                 * just do the right thing)
 430                 */
 431                if (S_ISDIR(st.st_mode)) {
 432                        /* If it is a gitlink, leave it alone! */
 433                        if (S_ISGITLINK(ce->ce_mode))
 434                                return 0;
 435                        if (!state->force)
 436                                return error("%s is a directory", path.buf);
 437                        remove_subtree(&path);
 438                } else if (unlink(path.buf))
 439                        return error_errno("unable to unlink old '%s'", path.buf);
 440        } else if (state->not_new)
 441                return 0;
 442
 443        create_directories(path.buf, path.len, state);
 444        return write_entry(ce, path.buf, state, 0);
 445}