src/futils.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "futils.h"
   9
  10 #include "runtime.h"
  11 #include "strmap.h"
  12 #include "hash.h"
  13 #include <ctype.h>
  14 #if GIT_WIN32
  15 #include "win32/findfile.h"
  16 #endif
  17
  18 int git_futils_mkpath2file(const char *file_path, const mode_t mode)
  19 {
  20         return git_futils_mkdir(
  21                 file_path, mode,
  22                 GIT_MKDIR_PATH | GIT_MKDIR_SKIP_LAST | GIT_MKDIR_VERIFY_DIR);
  23 }
  24
  25 int git_futils_mktmp(git_buf *path_out, const char *filename, mode_t mode)
  26 {
  27         int fd;
  28         mode_t mask;
  29
  30         p_umask(mask = p_umask(0));
  31
  32         git_buf_sets(path_out, filename);
  33         git_buf_puts(path_out, "_git2_XXXXXX");
  34
  35         if (git_buf_oom(path_out))
  36                 return -1;
  37
  38         if ((fd = p_mkstemp(path_out->ptr)) < 0) {
  39                 git_error_set(GIT_ERROR_OS,
  40                         "failed to create temporary file '%s'", path_out->ptr);
  41                 return -1;
  42         }
  43
  44         if (p_chmod(path_out->ptr, (mode & ~mask))) {
  45                 git_error_set(GIT_ERROR_OS,
  46                         "failed to set permissions on file '%s'", path_out->ptr);
  47                 return -1;
  48         }
  49
  50         return fd;
  51 }
  52
  53 int git_futils_creat_withpath(const char *path, const mode_t dirmode, const mode_t mode)
  54 {
  55         int fd;
  56
  57         if (git_futils_mkpath2file(path, dirmode) < 0)
  58                 return -1;
  59
  60         fd = p_creat(path, mode);
  61         if (fd < 0) {
  62                 git_error_set(GIT_ERROR_OS, "failed to create file '%s'", path);
  63                 return -1;
  64         }
  65
  66         return fd;
  67 }
  68
  69 int git_futils_creat_locked(const char *path, const mode_t mode)
  70 {
  71         int fd = p_open(path, O_WRONLY | O_CREAT | O_EXCL | O_BINARY | O_CLOEXEC,
  72                 mode);
  73
  74         if (fd < 0) {
  75                 int error = errno;
  76                 git_error_set(GIT_ERROR_OS, "failed to create locked file '%s'", path);
  77                 switch (error) {
  78                 case EEXIST:
  79                         return GIT_ELOCKED;
  80                 case ENOENT:
  81                         return GIT_ENOTFOUND;
  82                 default:
  83                         return -1;
  84                 }
  85         }
  86
  87         return fd;
  88 }
  89
  90 int git_futils_creat_locked_withpath(const char *path, const mode_t dirmode, const mode_t mode)
  91 {
  92         if (git_futils_mkpath2file(path, dirmode) < 0)
  93                 return -1;
  94
  95         return git_futils_creat_locked(path, mode);
  96 }
  97
  98 int git_futils_open_ro(const char *path)
  99 {
 100         int fd = p_open(path, O_RDONLY);
 101         if (fd < 0)
 102                 return git_path_set_error(errno, path, "open");
 103         return fd;
 104 }
 105
 106 int git_futils_truncate(const char *path, int mode)
 107 {
 108         int fd = p_open(path, O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, mode);
 109         if (fd < 0)
 110                 return git_path_set_error(errno, path, "open");
 111
 112         close(fd);
 113         return 0;
 114 }
 115
 116 int git_futils_filesize(uint64_t *out, git_file fd)
 117 {
 118         struct stat sb;
 119
 120         if (p_fstat(fd, &sb)) {
 121                 git_error_set(GIT_ERROR_OS, "failed to stat file descriptor");
 122                 return -1;
 123         }
 124
 125         if (sb.st_size < 0) {
 126                 git_error_set(GIT_ERROR_INVALID, "invalid file size");
 127                 return -1;
 128         }
 129
 130         *out = sb.st_size;
 131         return 0;
 132 }
 133
 134 mode_t git_futils_canonical_mode(mode_t raw_mode)
 135 {
 136         if (S_ISREG(raw_mode))
 137                 return S_IFREG | GIT_PERMS_CANONICAL(raw_mode);
 138         else if (S_ISLNK(raw_mode))
 139                 return S_IFLNK;
 140         else if (S_ISGITLINK(raw_mode))
 141                 return S_IFGITLINK;
 142         else if (S_ISDIR(raw_mode))
 143                 return S_IFDIR;
 144         else
 145                 return 0;
 146 }
 147
 148 int git_futils_readbuffer_fd(git_buf *buf, git_file fd, size_t len)
 149 {
 150         ssize_t read_size = 0;
 151         size_t alloc_len;
 152
 153         git_buf_clear(buf);
 154
 155         if (!git__is_ssizet(len)) {
 156                 git_error_set(GIT_ERROR_INVALID, "read too large");
 157                 return -1;
 158         }
 159
 160         GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, len, 1);
 161         if (git_buf_grow(buf, alloc_len) < 0)
 162                 return -1;
 163
 164         /* p_read loops internally to read len bytes */
 165         read_size = p_read(fd, buf->ptr, len);
 166
 167         if (read_size != (ssize_t)len) {
 168                 git_error_set(GIT_ERROR_OS, "failed to read descriptor");
 169                 git_buf_dispose(buf);
 170                 return -1;
 171         }
 172
 173         buf->ptr[read_size] = '\0';
 174         buf->size = read_size;
 175
 176         return 0;
 177 }
 178
 179 int git_futils_readbuffer_updated(
 180         git_buf *out, const char *path, git_oid *checksum, int *updated)
 181 {
 182         int error;
 183         git_file fd;
 184         struct stat st;
 185         git_buf buf = GIT_BUF_INIT;
 186         git_oid checksum_new;
 187
 188         GIT_ASSERT_ARG(out);
 189         GIT_ASSERT_ARG(path && *path);
 190
 191         if (updated != NULL)
 192                 *updated = 0;
 193
 194         if (p_stat(path, &st) < 0)
 195                 return git_path_set_error(errno, path, "stat");
 196
 197
 198         if (S_ISDIR(st.st_mode)) {
 199                 git_error_set(GIT_ERROR_INVALID, "requested file is a directory");
 200                 return GIT_ENOTFOUND;
 201         }
 202
 203         if (!git__is_sizet(st.st_size+1)) {
 204                 git_error_set(GIT_ERROR_OS, "invalid regular file stat for '%s'", path);
 205                 return -1;
 206         }
 207
 208         if ((fd = git_futils_open_ro(path)) < 0)
 209                 return fd;
 210
 211         if (git_futils_readbuffer_fd(&buf, fd, (size_t)st.st_size) < 0) {
 212                 p_close(fd);
 213                 return -1;
 214         }
 215
 216         p_close(fd);
 217
 218         if (checksum) {
 219                 if ((error = git_hash_buf(&checksum_new, buf.ptr, buf.size)) < 0) {
 220                         git_buf_dispose(&buf);
 221                         return error;
 222                 }
 223
 224                 /*
 225                  * If we were given a checksum, we only want to use it if it's different
 226                  */
 227                 if (!git_oid__cmp(checksum, &checksum_new)) {
 228                         git_buf_dispose(&buf);
 229                         if (updated)
 230                                 *updated = 0;
 231
 232                         return 0;
 233                 }
 234
 235                 git_oid_cpy(checksum, &checksum_new);
 236         }
 237
 238         /*
 239          * If we're here, the file did change, or the user didn't have an old version
 240          */
 241         if (updated != NULL)
 242                 *updated = 1;
 243
 244         git_buf_swap(out, &buf);
 245         git_buf_dispose(&buf);
 246
 247         return 0;
 248 }
 249
 250 int git_futils_readbuffer(git_buf *buf, const char *path)
 251 {
 252         return git_futils_readbuffer_updated(buf, path, NULL, NULL);
 253 }
 254
 255 int git_futils_writebuffer(
 256         const git_buf *buf,     const char *path, int flags, mode_t mode)
 257 {
 258         int fd, do_fsync = 0, error = 0;
 259
 260         if (!flags)
 261                 flags = O_CREAT | O_TRUNC | O_WRONLY;
 262
 263         if ((flags & O_FSYNC) != 0)
 264                 do_fsync = 1;
 265
 266         flags &= ~O_FSYNC;
 267
 268         if (!mode)
 269                 mode = GIT_FILEMODE_BLOB;
 270
 271         if ((fd = p_open(path, flags, mode)) < 0) {
 272                 git_error_set(GIT_ERROR_OS, "could not open '%s' for writing", path);
 273                 return fd;
 274         }
 275
 276         if ((error = p_write(fd, git_buf_cstr(buf), git_buf_len(buf))) < 0) {
 277                 git_error_set(GIT_ERROR_OS, "could not write to '%s'", path);
 278                 (void)p_close(fd);
 279                 return error;
 280         }
 281
 282         if (do_fsync && (error = p_fsync(fd)) < 0) {
 283                 git_error_set(GIT_ERROR_OS, "could not fsync '%s'", path);
 284                 p_close(fd);
 285                 return error;
 286         }
 287
 288         if ((error = p_close(fd)) < 0) {
 289                 git_error_set(GIT_ERROR_OS, "error while closing '%s'", path);
 290                 return error;
 291         }
 292
 293         if (do_fsync && (flags & O_CREAT))
 294                 error = git_futils_fsync_parent(path);
 295
 296         return error;
 297 }
 298
 299 int git_futils_mv_withpath(const char *from, const char *to, const mode_t dirmode)
 300 {
 301         if (git_futils_mkpath2file(to, dirmode) < 0)
 302                 return -1;
 303
 304         if (p_rename(from, to) < 0) {
 305                 git_error_set(GIT_ERROR_OS, "failed to rename '%s' to '%s'", from, to);
 306                 return -1;
 307         }
 308
 309         return 0;
 310 }
 311
 312 int git_futils_mmap_ro(git_map *out, git_file fd, off64_t begin, size_t len)
 313 {
 314         return p_mmap(out, len, GIT_PROT_READ, GIT_MAP_SHARED, fd, begin);
 315 }
 316
 317 int git_futils_mmap_ro_file(git_map *out, const char *path)
 318 {
 319         git_file fd = git_futils_open_ro(path);
 320         uint64_t len;
 321         int result;
 322
 323         if (fd < 0)
 324                 return fd;
 325
 326         if ((result = git_futils_filesize(&len, fd)) < 0)
 327                 goto out;
 328
 329         if (!git__is_sizet(len)) {
 330                 git_error_set(GIT_ERROR_OS, "file `%s` too large to mmap", path);
 331                 result = -1;
 332                 goto out;
 333         }
 334
 335         result = git_futils_mmap_ro(out, fd, 0, (size_t)len);
 336 out:
 337         p_close(fd);
 338         return result;
 339 }
 340
 341 void git_futils_mmap_free(git_map *out)
 342 {
 343         p_munmap(out);
 344 }
 345
 346 GIT_INLINE(int) mkdir_validate_dir(
 347         const char *path,
 348         struct stat *st,
 349         mode_t mode,
 350         uint32_t flags,
 351         struct git_futils_mkdir_options *opts)
 352 {
 353         /* with exclusive create, existing dir is an error */
 354         if ((flags & GIT_MKDIR_EXCL) != 0) {
 355                 git_error_set(GIT_ERROR_FILESYSTEM,
 356                         "failed to make directory '%s': directory exists", path);
 357                 return GIT_EEXISTS;
 358         }
 359
 360         if ((S_ISREG(st->st_mode) && (flags & GIT_MKDIR_REMOVE_FILES)) ||
 361                 (S_ISLNK(st->st_mode) && (flags & GIT_MKDIR_REMOVE_SYMLINKS))) {
 362                 if (p_unlink(path) < 0) {
 363                         git_error_set(GIT_ERROR_OS, "failed to remove %s '%s'",
 364                                 S_ISLNK(st->st_mode) ? "symlink" : "file", path);
 365                         return GIT_EEXISTS;
 366                 }
 367
 368                 opts->perfdata.mkdir_calls++;
 369
 370                 if (p_mkdir(path, mode) < 0) {
 371                         git_error_set(GIT_ERROR_OS, "failed to make directory '%s'", path);
 372                         return GIT_EEXISTS;
 373                 }
 374         }
 375
 376         else if (S_ISLNK(st->st_mode)) {
 377                 /* Re-stat the target, make sure it's a directory */
 378                 opts->perfdata.stat_calls++;
 379
 380                 if (p_stat(path, st) < 0) {
 381                         git_error_set(GIT_ERROR_OS, "failed to make directory '%s'", path);
 382                         return GIT_EEXISTS;
 383                 }
 384         }
 385
 386         else if (!S_ISDIR(st->st_mode)) {
 387                 git_error_set(GIT_ERROR_FILESYSTEM,
 388                         "failed to make directory '%s': directory exists", path);
 389                 return GIT_EEXISTS;
 390         }
 391
 392         return 0;
 393 }
 394
 395 GIT_INLINE(int) mkdir_validate_mode(
 396         const char *path,
 397         struct stat *st,
 398         bool terminal_path,
 399         mode_t mode,
 400         uint32_t flags,
 401         struct git_futils_mkdir_options *opts)
 402 {
 403         if (((terminal_path && (flags & GIT_MKDIR_CHMOD) != 0) ||
 404                 (flags & GIT_MKDIR_CHMOD_PATH) != 0) && st->st_mode != mode) {
 405
 406                 opts->perfdata.chmod_calls++;
 407
 408                 if (p_chmod(path, mode) < 0) {
 409                         git_error_set(GIT_ERROR_OS, "failed to set permissions on '%s'", path);
 410                         return -1;
 411                 }
 412         }
 413
 414         return 0;
 415 }
 416
 417 GIT_INLINE(int) mkdir_canonicalize(
 418         git_buf *path,
 419         uint32_t flags)
 420 {
 421         ssize_t root_len;
 422
 423         if (path->size == 0) {
 424                 git_error_set(GIT_ERROR_OS, "attempt to create empty path");
 425                 return -1;
 426         }
 427
 428         /* Trim trailing slashes (except the root) */
 429         if ((root_len = git_path_root(path->ptr)) < 0)
 430                 root_len = 0;
 431         else
 432                 root_len++;
 433
 434         while (path->size > (size_t)root_len && path->ptr[path->size - 1] == '/')
 435                 path->ptr[--path->size] = '\0';
 436
 437         /* if we are not supposed to made the last element, truncate it */
 438         if ((flags & GIT_MKDIR_SKIP_LAST2) != 0) {
 439                 git_path_dirname_r(path, path->ptr);
 440                 flags |= GIT_MKDIR_SKIP_LAST;
 441         }
 442         if ((flags & GIT_MKDIR_SKIP_LAST) != 0) {
 443                 git_path_dirname_r(path, path->ptr);
 444         }
 445
 446         /* We were either given the root path (or trimmed it to
 447         * the root), we don't have anything to do.
 448         */
 449         if (path->size <= (size_t)root_len)
 450                 git_buf_clear(path);
 451
 452         return 0;
 453 }
 454
 455 int git_futils_mkdir(
 456         const char *path,
 457         mode_t mode,
 458         uint32_t flags)
 459 {
 460         git_buf make_path = GIT_BUF_INIT, parent_path = GIT_BUF_INIT;
 461         const char *relative;
 462         struct git_futils_mkdir_options opts = { 0 };
 463         struct stat st;
 464         size_t depth = 0;
 465         int len = 0, root_len, error;
 466
 467         if ((error = git_buf_puts(&make_path, path)) < 0 ||
 468                 (error = mkdir_canonicalize(&make_path, flags)) < 0 ||
 469                 (error = git_buf_puts(&parent_path, make_path.ptr)) < 0 ||
 470                 make_path.size == 0)
 471                 goto done;
 472
 473         root_len = git_path_root(make_path.ptr);
 474
 475         /* find the first parent directory that exists.  this will be used
 476          * as the base to dirname_relative.
 477          */
 478         for (relative = make_path.ptr; parent_path.size; ) {
 479                 error = p_lstat(parent_path.ptr, &st);
 480
 481                 if (error == 0) {
 482                         break;
 483                 } else if (errno != ENOENT) {
 484                         git_error_set(GIT_ERROR_OS, "failed to stat '%s'", parent_path.ptr);
 485                         error = -1;
 486                         goto done;
 487                 }
 488
 489                 depth++;
 490
 491                 /* examine the parent of the current path */
 492                 if ((len = git_path_dirname_r(&parent_path, parent_path.ptr)) < 0) {
 493                         error = len;
 494                         goto done;
 495                 }
 496
 497                 GIT_ASSERT(len);
 498
 499                 /*
 500                  * We've walked all the given path's parents and it's either relative
 501                  * (the parent is simply '.') or rooted (the length is less than or
 502                  * equal to length of the root path).  The path may be less than the
 503                  * root path length on Windows, where `C:` == `C:/`.
 504                  */
 505                 if ((len == 1 && parent_path.ptr[0] == '.') ||
 506                     (len == 1 && parent_path.ptr[0] == '/') ||
 507                     len <= root_len) {
 508                         relative = make_path.ptr;
 509                         break;
 510                 }
 511
 512                 relative = make_path.ptr + len + 1;
 513
 514                 /* not recursive? just make this directory relative to its parent. */
 515                 if ((flags & GIT_MKDIR_PATH) == 0)
 516                         break;
 517         }
 518
 519         /* we found an item at the location we're trying to create,
 520          * validate it.
 521          */
 522         if (depth == 0) {
 523                 error = mkdir_validate_dir(make_path.ptr, &st, mode, flags, &opts);
 524
 525                 if (!error)
 526                         error = mkdir_validate_mode(
 527                                 make_path.ptr, &st, true, mode, flags, &opts);
 528
 529                 goto done;
 530         }
 531
 532         /* we already took `SKIP_LAST` and `SKIP_LAST2` into account when
 533          * canonicalizing `make_path`.
 534          */
 535         flags &= ~(GIT_MKDIR_SKIP_LAST2 | GIT_MKDIR_SKIP_LAST);
 536
 537         error = git_futils_mkdir_relative(relative,
 538                 parent_path.size ? parent_path.ptr : NULL, mode, flags, &opts);
 539
 540 done:
 541         git_buf_dispose(&make_path);
 542         git_buf_dispose(&parent_path);
 543         return error;
 544 }
 545
 546 int git_futils_mkdir_r(const char *path, const mode_t mode)
 547 {
 548         return git_futils_mkdir(path, mode, GIT_MKDIR_PATH);
 549 }
 550
 551 int git_futils_mkdir_relative(
 552         const char *relative_path,
 553         const char *base,
 554         mode_t mode,
 555         uint32_t flags,
 556         struct git_futils_mkdir_options *opts)
 557 {
 558         git_buf make_path = GIT_BUF_INIT;
 559         ssize_t root = 0, min_root_len;
 560         char lastch = '/', *tail;
 561         struct stat st;
 562         struct git_futils_mkdir_options empty_opts = {0};
 563         int error;
 564
 565         if (!opts)
 566                 opts = &empty_opts;
 567
 568         /* build path and find "root" where we should start calling mkdir */
 569         if (git_path_join_unrooted(&make_path, relative_path, base, &root) < 0)
 570                 return -1;
 571
 572         if ((error = mkdir_canonicalize(&make_path, flags)) < 0 ||
 573                 make_path.size == 0)
 574                 goto done;
 575
 576         /* if we are not supposed to make the whole path, reset root */
 577         if ((flags & GIT_MKDIR_PATH) == 0)
 578                 root = git_buf_rfind(&make_path, '/');
 579
 580         /* advance root past drive name or network mount prefix */
 581         min_root_len = git_path_root(make_path.ptr);
 582         if (root < min_root_len)
 583                 root = min_root_len;
 584         while (root >= 0 && make_path.ptr[root] == '/')
 585                 ++root;
 586
 587         /* clip root to make_path length */
 588         if (root > (ssize_t)make_path.size)
 589                 root = (ssize_t)make_path.size; /* i.e. NUL byte of string */
 590         if (root < 0)
 591                 root = 0;
 592
 593         /* walk down tail of path making each directory */
 594         for (tail = &make_path.ptr[root]; *tail; *tail = lastch) {
 595                 bool mkdir_attempted = false;
 596
 597                 /* advance tail to include next path component */
 598                 while (*tail == '/')
 599                         tail++;
 600                 while (*tail && *tail != '/')
 601                         tail++;
 602
 603                 /* truncate path at next component */
 604                 lastch = *tail;
 605                 *tail = '\0';
 606                 st.st_mode = 0;
 607
 608                 if (opts->dir_map && git_strmap_exists(opts->dir_map, make_path.ptr))
 609                         continue;
 610
 611                 /* See what's going on with this path component */
 612                 opts->perfdata.stat_calls++;
 613
 614 retry_lstat:
 615                 if (p_lstat(make_path.ptr, &st) < 0) {
 616                         if (mkdir_attempted || errno != ENOENT) {
 617                                 git_error_set(GIT_ERROR_OS, "cannot access component in path '%s'", make_path.ptr);
 618                                 error = -1;
 619                                 goto done;
 620                         }
 621
 622                         git_error_clear();
 623                         opts->perfdata.mkdir_calls++;
 624                         mkdir_attempted = true;
 625                         if (p_mkdir(make_path.ptr, mode) < 0) {
 626                                 if (errno == EEXIST)
 627                                         goto retry_lstat;
 628                                 git_error_set(GIT_ERROR_OS, "failed to make directory '%s'", make_path.ptr);
 629                                 error = -1;
 630                                 goto done;
 631                         }
 632                 } else {
 633                         if ((error = mkdir_validate_dir(
 634                                 make_path.ptr, &st, mode, flags, opts)) < 0)
 635                                 goto done;
 636                 }
 637
 638                 /* chmod if requested and necessary */
 639                 if ((error = mkdir_validate_mode(
 640                         make_path.ptr, &st, (lastch == '\0'), mode, flags, opts)) < 0)
 641                         goto done;
 642
 643                 if (opts->dir_map && opts->pool) {
 644                         char *cache_path;
 645                         size_t alloc_size;
 646
 647                         GIT_ERROR_CHECK_ALLOC_ADD(&alloc_size, make_path.size, 1);
 648                         cache_path = git_pool_malloc(opts->pool, alloc_size);
 649                         GIT_ERROR_CHECK_ALLOC(cache_path);
 650
 651                         memcpy(cache_path, make_path.ptr, make_path.size + 1);
 652
 653                         if ((error = git_strmap_set(opts->dir_map, cache_path, cache_path)) < 0)
 654                                 goto done;
 655                 }
 656         }
 657
 658         error = 0;
 659
 660         /* check that full path really is a directory if requested & needed */
 661         if ((flags & GIT_MKDIR_VERIFY_DIR) != 0 &&
 662                 lastch != '\0') {
 663                 opts->perfdata.stat_calls++;
 664
 665                 if (p_stat(make_path.ptr, &st) < 0 || !S_ISDIR(st.st_mode)) {
 666                         git_error_set(GIT_ERROR_OS, "path is not a directory '%s'",
 667                                 make_path.ptr);
 668                         error = GIT_ENOTFOUND;
 669                 }
 670         }
 671
 672 done:
 673         git_buf_dispose(&make_path);
 674         return error;
 675 }
 676
 677 typedef struct {
 678         const char *base;
 679         size_t baselen;
 680         uint32_t flags;
 681         int depth;
 682 } futils__rmdir_data;
 683
 684 #define FUTILS_MAX_DEPTH 100
 685
 686 static int futils__error_cannot_rmdir(const char *path, const char *filemsg)
 687 {
 688         if (filemsg)
 689                 git_error_set(GIT_ERROR_OS, "could not remove directory '%s': %s",
 690                                    path, filemsg);
 691         else
 692                 git_error_set(GIT_ERROR_OS, "could not remove directory '%s'", path);
 693
 694         return -1;
 695 }
 696
 697 static int futils__rm_first_parent(git_buf *path, const char *ceiling)
 698 {
 699         int error = GIT_ENOTFOUND;
 700         struct stat st;
 701
 702         while (error == GIT_ENOTFOUND) {
 703                 git_buf_rtruncate_at_char(path, '/');
 704
 705                 if (!path->size || git__prefixcmp(path->ptr, ceiling) != 0)
 706                         error = 0;
 707                 else if (p_lstat_posixly(path->ptr, &st) == 0) {
 708                         if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode))
 709                                 error = p_unlink(path->ptr);
 710                         else if (!S_ISDIR(st.st_mode))
 711                                 error = -1; /* fail to remove non-regular file */
 712                 } else if (errno != ENOTDIR)
 713                         error = -1;
 714         }
 715
 716         if (error)
 717                 futils__error_cannot_rmdir(path->ptr, "cannot remove parent");
 718
 719         return error;
 720 }
 721
 722 static int futils__rmdir_recurs_foreach(void *opaque, git_buf *path)
 723 {
 724         int error = 0;
 725         futils__rmdir_data *data = opaque;
 726         struct stat st;
 727
 728         if (data->depth > FUTILS_MAX_DEPTH)
 729                 error = futils__error_cannot_rmdir(
 730                         path->ptr, "directory nesting too deep");
 731
 732         else if ((error = p_lstat_posixly(path->ptr, &st)) < 0) {
 733                 if (errno == ENOENT)
 734                         error = 0;
 735                 else if (errno == ENOTDIR) {
 736                         /* asked to remove a/b/c/d/e and a/b is a normal file */
 737                         if ((data->flags & GIT_RMDIR_REMOVE_BLOCKERS) != 0)
 738                                 error = futils__rm_first_parent(path, data->base);
 739                         else
 740                                 futils__error_cannot_rmdir(
 741                                         path->ptr, "parent is not directory");
 742                 }
 743                 else
 744                         error = git_path_set_error(errno, path->ptr, "rmdir");
 745         }
 746
 747         else if (S_ISDIR(st.st_mode)) {
 748                 data->depth++;
 749
 750                 error = git_path_direach(path, 0, futils__rmdir_recurs_foreach, data);
 751
 752                 data->depth--;
 753
 754                 if (error < 0)
 755                         return error;
 756
 757                 if (data->depth == 0 && (data->flags & GIT_RMDIR_SKIP_ROOT) != 0)
 758                         return error;
 759
 760                 if ((error = p_rmdir(path->ptr)) < 0) {
 761                         if ((data->flags & GIT_RMDIR_SKIP_NONEMPTY) != 0 &&
 762                                 (errno == ENOTEMPTY || errno == EEXIST || errno == EBUSY))
 763                                 error = 0;
 764                         else
 765                                 error = git_path_set_error(errno, path->ptr, "rmdir");
 766                 }
 767         }
 768
 769         else if ((data->flags & GIT_RMDIR_REMOVE_FILES) != 0) {
 770                 if (p_unlink(path->ptr) < 0)
 771                         error = git_path_set_error(errno, path->ptr, "remove");
 772         }
 773
 774         else if ((data->flags & GIT_RMDIR_SKIP_NONEMPTY) == 0)
 775                 error = futils__error_cannot_rmdir(path->ptr, "still present");
 776
 777         return error;
 778 }
 779
 780 static int futils__rmdir_empty_parent(void *opaque, const char *path)
 781 {
 782         futils__rmdir_data *data = opaque;
 783         int error = 0;
 784
 785         if (strlen(path) <= data->baselen)
 786                 error = GIT_ITEROVER;
 787
 788         else if (p_rmdir(path) < 0) {
 789                 int en = errno;
 790
 791                 if (en == ENOENT || en == ENOTDIR) {
 792                         /* do nothing */
 793                 } else if ((data->flags & GIT_RMDIR_SKIP_NONEMPTY) == 0 &&
 794                         en == EBUSY) {
 795                         error = git_path_set_error(errno, path, "rmdir");
 796                 } else if (en == ENOTEMPTY || en == EEXIST || en == EBUSY) {
 797                         error = GIT_ITEROVER;
 798                 } else {
 799                         error = git_path_set_error(errno, path, "rmdir");
 800                 }
 801         }
 802
 803         return error;
 804 }
 805
 806 int git_futils_rmdir_r(
 807         const char *path, const char *base, uint32_t flags)
 808 {
 809         int error;
 810         git_buf fullpath = GIT_BUF_INIT;
 811         futils__rmdir_data data;
 812
 813         /* build path and find "root" where we should start calling mkdir */
 814         if (git_path_join_unrooted(&fullpath, path, base, NULL) < 0)
 815                 return -1;
 816
 817         memset(&data, 0, sizeof(data));
 818         data.base    = base ? base : "";
 819         data.baselen = base ? strlen(base) : 0;
 820         data.flags   = flags;
 821
 822         error = futils__rmdir_recurs_foreach(&data, &fullpath);
 823
 824         /* remove now-empty parents if requested */
 825         if (!error && (flags & GIT_RMDIR_EMPTY_PARENTS) != 0)
 826                 error = git_path_walk_up(
 827                         &fullpath, base, futils__rmdir_empty_parent, &data);
 828
 829         if (error == GIT_ITEROVER) {
 830                 git_error_clear();
 831                 error = 0;
 832         }
 833
 834         git_buf_dispose(&fullpath);
 835
 836         return error;
 837 }
 838
 839 int git_futils_fake_symlink(const char *target, const char *path)
 840 {
 841         int retcode = GIT_ERROR;
 842         int fd = git_futils_creat_withpath(path, 0755, 0644);
 843         if (fd >= 0) {
 844                 retcode = p_write(fd, target, strlen(target));
 845                 p_close(fd);
 846         }
 847         return retcode;
 848 }
 849
 850 static int cp_by_fd(int ifd, int ofd, bool close_fd_when_done)
 851 {
 852         int error = 0;
 853         char buffer[FILEIO_BUFSIZE];
 854         ssize_t len = 0;
 855
 856         while (!error && (len = p_read(ifd, buffer, sizeof(buffer))) > 0)
 857                 /* p_write() does not have the same semantics as write().  It loops
 858                  * internally and will return 0 when it has completed writing.
 859                  */
 860                 error = p_write(ofd, buffer, len);
 861
 862         if (len < 0) {
 863                 git_error_set(GIT_ERROR_OS, "read error while copying file");
 864                 error = (int)len;
 865         }
 866
 867         if (error < 0)
 868                 git_error_set(GIT_ERROR_OS, "write error while copying file");
 869
 870         if (close_fd_when_done) {
 871                 p_close(ifd);
 872                 p_close(ofd);
 873         }
 874
 875         return error;
 876 }
 877
 878 int git_futils_cp(const char *from, const char *to, mode_t filemode)
 879 {
 880         int ifd, ofd;
 881
 882         if ((ifd = git_futils_open_ro(from)) < 0)
 883                 return ifd;
 884
 885         if ((ofd = p_open(to, O_WRONLY | O_CREAT | O_EXCL, filemode)) < 0) {
 886                 p_close(ifd);
 887                 return git_path_set_error(errno, to, "open for writing");
 888         }
 889
 890         return cp_by_fd(ifd, ofd, true);
 891 }
 892
 893 int git_futils_touch(const char *path, time_t *when)
 894 {
 895         struct p_timeval times[2];
 896         int ret;
 897
 898         times[0].tv_sec =  times[1].tv_sec  = when ? *when : time(NULL);
 899         times[0].tv_usec = times[1].tv_usec = 0;
 900
 901         ret = p_utimes(path, times);
 902
 903         return (ret < 0) ? git_path_set_error(errno, path, "touch") : 0;
 904 }
 905
 906 static int cp_link(const char *from, const char *to, size_t link_size)
 907 {
 908         int error = 0;
 909         ssize_t read_len;
 910         char *link_data;
 911         size_t alloc_size;
 912
 913         GIT_ERROR_CHECK_ALLOC_ADD(&alloc_size, link_size, 1);
 914         link_data = git__malloc(alloc_size);
 915         GIT_ERROR_CHECK_ALLOC(link_data);
 916
 917         read_len = p_readlink(from, link_data, link_size);
 918         if (read_len != (ssize_t)link_size) {
 919                 git_error_set(GIT_ERROR_OS, "failed to read symlink data for '%s'", from);
 920                 error = -1;
 921         }
 922         else {
 923                 link_data[read_len] = '\0';
 924
 925                 if (p_symlink(link_data, to) < 0) {
 926                         git_error_set(GIT_ERROR_OS, "could not symlink '%s' as '%s'",
 927                                 link_data, to);
 928                         error = -1;
 929                 }
 930         }
 931
 932         git__free(link_data);
 933         return error;
 934 }
 935
 936 typedef struct {
 937         const char *to_root;
 938         git_buf to;
 939         ssize_t from_prefix;
 940         uint32_t flags;
 941         uint32_t mkdir_flags;
 942         mode_t dirmode;
 943 } cp_r_info;
 944
 945 #define GIT_CPDIR__MKDIR_DONE_FOR_TO_ROOT (1u << 10)
 946
 947 static int _cp_r_mkdir(cp_r_info *info, git_buf *from)
 948 {
 949         int error = 0;
 950
 951         /* create root directory the first time we need to create a directory */
 952         if ((info->flags & GIT_CPDIR__MKDIR_DONE_FOR_TO_ROOT) == 0) {
 953                 error = git_futils_mkdir(
 954                         info->to_root, info->dirmode,
 955                         (info->flags & GIT_CPDIR_CHMOD_DIRS) ? GIT_MKDIR_CHMOD : 0);
 956
 957                 info->flags |= GIT_CPDIR__MKDIR_DONE_FOR_TO_ROOT;
 958         }
 959
 960         /* create directory with root as base to prevent excess chmods */
 961         if (!error)
 962                 error = git_futils_mkdir_relative(
 963                         from->ptr + info->from_prefix, info->to_root,
 964                         info->dirmode, info->mkdir_flags, NULL);
 965
 966         return error;
 967 }
 968
 969 static int _cp_r_callback(void *ref, git_buf *from)
 970 {
 971         int error = 0;
 972         cp_r_info *info = ref;
 973         struct stat from_st, to_st;
 974         bool exists = false;
 975
 976         if ((info->flags & GIT_CPDIR_COPY_DOTFILES) == 0 &&
 977                 from->ptr[git_path_basename_offset(from)] == '.')
 978                 return 0;
 979
 980         if ((error = git_buf_joinpath(
 981                         &info->to, info->to_root, from->ptr + info->from_prefix)) < 0)
 982                 return error;
 983
 984         if (!(error = git_path_lstat(info->to.ptr, &to_st)))
 985                 exists = true;
 986         else if (error != GIT_ENOTFOUND)
 987                 return error;
 988         else {
 989                 git_error_clear();
 990                 error = 0;
 991         }
 992
 993         if ((error = git_path_lstat(from->ptr, &from_st)) < 0)
 994                 return error;
 995
 996         if (S_ISDIR(from_st.st_mode)) {
 997                 mode_t oldmode = info->dirmode;
 998
 999                 /* if we are not chmod'ing, then overwrite dirmode */
1000                 if ((info->flags & GIT_CPDIR_CHMOD_DIRS) == 0)
1001                         info->dirmode = from_st.st_mode;
1002
1003                 /* make directory now if CREATE_EMPTY_DIRS is requested and needed */
1004                 if (!exists && (info->flags & GIT_CPDIR_CREATE_EMPTY_DIRS) != 0)
1005                         error = _cp_r_mkdir(info, from);
1006
1007                 /* recurse onto target directory */
1008                 if (!error && (!exists || S_ISDIR(to_st.st_mode)))
1009                         error = git_path_direach(from, 0, _cp_r_callback, info);
1010
1011                 if (oldmode != 0)
1012                         info->dirmode = oldmode;
1013
1014                 return error;
1015         }
1016
1017         if (exists) {
1018                 if ((info->flags & GIT_CPDIR_OVERWRITE) == 0)
1019                         return 0;
1020
1021                 if (p_unlink(info->to.ptr) < 0) {
1022                         git_error_set(GIT_ERROR_OS, "cannot overwrite existing file '%s'",
1023                                 info->to.ptr);
1024                         return GIT_EEXISTS;
1025                 }
1026         }
1027
1028         /* Done if this isn't a regular file or a symlink */
1029         if (!S_ISREG(from_st.st_mode) &&
1030                 (!S_ISLNK(from_st.st_mode) ||
1031                  (info->flags & GIT_CPDIR_COPY_SYMLINKS) == 0))
1032                 return 0;
1033
1034         /* Make container directory on demand if needed */
1035         if ((info->flags & GIT_CPDIR_CREATE_EMPTY_DIRS) == 0 &&
1036                 (error = _cp_r_mkdir(info, from)) < 0)
1037                 return error;
1038
1039         /* make symlink or regular file */
1040         if (info->flags & GIT_CPDIR_LINK_FILES) {
1041                 if ((error = p_link(from->ptr, info->to.ptr)) < 0)
1042                         git_error_set(GIT_ERROR_OS, "failed to link '%s'", from->ptr);
1043         } else if (S_ISLNK(from_st.st_mode)) {
1044                 error = cp_link(from->ptr, info->to.ptr, (size_t)from_st.st_size);
1045         } else {
1046                 mode_t usemode = from_st.st_mode;
1047
1048                 if ((info->flags & GIT_CPDIR_SIMPLE_TO_MODE) != 0)
1049                         usemode = GIT_PERMS_FOR_WRITE(usemode);
1050
1051                 error = git_futils_cp(from->ptr, info->to.ptr, usemode);
1052         }
1053
1054         return error;
1055 }
1056
1057 int git_futils_cp_r(
1058         const char *from,
1059         const char *to,
1060         uint32_t flags,
1061         mode_t dirmode)
1062 {
1063         int error;
1064         git_buf path = GIT_BUF_INIT;
1065         cp_r_info info;
1066
1067         if (git_buf_joinpath(&path, from, "") < 0) /* ensure trailing slash */
1068                 return -1;
1069
1070         memset(&info, 0, sizeof(info));
1071         info.to_root = to;
1072         info.flags   = flags;
1073         info.dirmode = dirmode;
1074         info.from_prefix = path.size;
1075         git_buf_init(&info.to, 0);
1076
1077         /* precalculate mkdir flags */
1078         if ((flags & GIT_CPDIR_CREATE_EMPTY_DIRS) == 0) {
1079                 /* if not creating empty dirs, then use mkdir to create the path on
1080                  * demand right before files are copied.
1081                  */
1082                 info.mkdir_flags = GIT_MKDIR_PATH | GIT_MKDIR_SKIP_LAST;
1083                 if ((flags & GIT_CPDIR_CHMOD_DIRS) != 0)
1084                         info.mkdir_flags |= GIT_MKDIR_CHMOD_PATH;
1085         } else {
1086                 /* otherwise, we will do simple mkdir as directories are encountered */
1087                 info.mkdir_flags =
1088                         ((flags & GIT_CPDIR_CHMOD_DIRS) != 0) ? GIT_MKDIR_CHMOD : 0;
1089         }
1090
1091         error = _cp_r_callback(&info, &path);
1092
1093         git_buf_dispose(&path);
1094         git_buf_dispose(&info.to);
1095
1096         return error;
1097 }
1098
1099 int git_futils_filestamp_check(
1100         git_futils_filestamp *stamp, const char *path)
1101 {
1102         struct stat st;
1103
1104         /* if the stamp is NULL, then always reload */
1105         if (stamp == NULL)
1106                 return 1;
1107
1108         if (p_stat(path, &st) < 0)
1109                 return GIT_ENOTFOUND;
1110
1111         if (stamp->mtime.tv_sec == st.st_mtime &&
1112 #if defined(GIT_USE_NSEC)
1113                 stamp->mtime.tv_nsec == st.st_mtime_nsec &&
1114 #endif
1115                 stamp->size  == (uint64_t)st.st_size   &&
1116                 stamp->ino   == (unsigned int)st.st_ino)
1117                 return 0;
1118
1119         stamp->mtime.tv_sec = st.st_mtime;
1120 #if defined(GIT_USE_NSEC)
1121         stamp->mtime.tv_nsec = st.st_mtime_nsec;
1122 #endif
1123         stamp->size  = (uint64_t)st.st_size;
1124         stamp->ino   = (unsigned int)st.st_ino;
1125
1126         return 1;
1127 }
1128
1129 void git_futils_filestamp_set(
1130         git_futils_filestamp *target, const git_futils_filestamp *source)
1131 {
1132         if (source)
1133                 memcpy(target, source, sizeof(*target));
1134         else
1135                 memset(target, 0, sizeof(*target));
1136 }
1137
1138
1139 void git_futils_filestamp_set_from_stat(
1140         git_futils_filestamp *stamp, struct stat *st)
1141 {
1142         if (st) {
1143                 stamp->mtime.tv_sec = st->st_mtime;
1144 #if defined(GIT_USE_NSEC)
1145                 stamp->mtime.tv_nsec = st->st_mtime_nsec;
1146 #else
1147                 stamp->mtime.tv_nsec = 0;
1148 #endif
1149                 stamp->size  = (uint64_t)st->st_size;
1150                 stamp->ino   = (unsigned int)st->st_ino;
1151         } else {
1152                 memset(stamp, 0, sizeof(*stamp));
1153         }
1154 }
1155
1156 int git_futils_fsync_dir(const char *path)
1157 {
1158 #ifdef GIT_WIN32
1159         GIT_UNUSED(path);
1160         return 0;
1161 #else
1162         int fd, error = -1;
1163
1164         if ((fd = p_open(path, O_RDONLY)) < 0) {
1165                 git_error_set(GIT_ERROR_OS, "failed to open directory '%s' for fsync", path);
1166                 return -1;
1167         }
1168
1169         if ((error = p_fsync(fd)) < 0)
1170                 git_error_set(GIT_ERROR_OS, "failed to fsync directory '%s'", path);
1171
1172         p_close(fd);
1173         return error;
1174 #endif
1175 }
1176
1177 int git_futils_fsync_parent(const char *path)
1178 {
1179         char *parent;
1180         int error;
1181
1182         if ((parent = git_path_dirname(path)) == NULL)
1183                 return -1;
1184
1185         error = git_futils_fsync_dir(parent);
1186         git__free(parent);
1187         return error;
1188 }