src/filesys.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "filesys.h"
  21 #include "util/string.h"
  22 #include <iostream>
  23 #include <cstdio>
  24 #include <cstdlib>
  25 #include <cstring>
  26 #include <cerrno>
  27 #include <fstream>
  28 #include "log.h"
  29 #include "config.h"
  30 #include "porting.h"
  31 #ifndef SERVER
  32 #include "irr_ptr.h"
  33 #endif
  34
  35 namespace fs
  36 {
  37
  38 #ifdef _WIN32
  39
  40 /***********
  41  * Windows *
  42  ***********/
  43
  44 #define _WIN32_WINNT 0x0501
  45 #include <windows.h>
  46 #include <shlwapi.h>
  47 #include <io.h>
  48 #include <direct.h>
  49
  50 std::vector<DirListNode> GetDirListing(const std::string &pathstring)
  51 {
  52         std::vector<DirListNode> listing;
  53
  54         WIN32_FIND_DATA FindFileData;
  55         HANDLE hFind = INVALID_HANDLE_VALUE;
  56         DWORD dwError;
  57
  58         std::string dirSpec = pathstring + "\\*";
  59
  60         // Find the first file in the directory.
  61         hFind = FindFirstFile(dirSpec.c_str(), &FindFileData);
  62
  63         if (hFind == INVALID_HANDLE_VALUE) {
  64                 dwError = GetLastError();
  65                 if (dwError != ERROR_FILE_NOT_FOUND && dwError != ERROR_PATH_NOT_FOUND) {
  66                         errorstream << "GetDirListing: FindFirstFile error."
  67                                         << " Error is " << dwError << std::endl;
  68                 }
  69         } else {
  70                 // NOTE:
  71                 // Be very sure to not include '..' in the results, it will
  72                 // result in an epic failure when deleting stuff.
  73
  74                 DirListNode node;
  75                 node.name = FindFileData.cFileName;
  76                 node.dir = FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
  77                 if (node.name != "." && node.name != "..")
  78                         listing.push_back(node);
  79
  80                 // List all the other files in the directory.
  81                 while (FindNextFile(hFind, &FindFileData) != 0) {
  82                         DirListNode node;
  83                         node.name = FindFileData.cFileName;
  84                         node.dir = FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY;
  85                         if(node.name != "." && node.name != "..")
  86                                 listing.push_back(node);
  87                 }
  88
  89                 dwError = GetLastError();
  90                 FindClose(hFind);
  91                 if (dwError != ERROR_NO_MORE_FILES) {
  92                         errorstream << "GetDirListing: FindNextFile error."
  93                                         << " Error is " << dwError << std::endl;
  94                         listing.clear();
  95                         return listing;
  96                 }
  97         }
  98         return listing;
  99 }
 100
 101 bool CreateDir(const std::string &path)
 102 {
 103         bool r = CreateDirectory(path.c_str(), NULL);
 104         if(r == true)
 105                 return true;
 106         if(GetLastError() == ERROR_ALREADY_EXISTS)
 107                 return true;
 108         return false;
 109 }
 110
 111 bool PathExists(const std::string &path)
 112 {
 113         return (GetFileAttributes(path.c_str()) != INVALID_FILE_ATTRIBUTES);
 114 }
 115
 116 bool IsPathAbsolute(const std::string &path)
 117 {
 118         return !PathIsRelative(path.c_str());
 119 }
 120
 121 bool IsDir(const std::string &path)
 122 {
 123         DWORD attr = GetFileAttributes(path.c_str());
 124         return (attr != INVALID_FILE_ATTRIBUTES &&
 125                         (attr & FILE_ATTRIBUTE_DIRECTORY));
 126 }
 127
 128 bool IsDirDelimiter(char c)
 129 {
 130         return c == '/' || c == '\\';
 131 }
 132
 133 bool RecursiveDelete(const std::string &path)
 134 {
 135         infostream << "Recursively deleting \"" << path << "\"" << std::endl;
 136         if (!IsDir(path)) {
 137                 infostream << "RecursiveDelete: Deleting file  " << path << std::endl;
 138                 if (!DeleteFile(path.c_str())) {
 139                         errorstream << "RecursiveDelete: Failed to delete file "
 140                                         << path << std::endl;
 141                         return false;
 142                 }
 143                 return true;
 144         }
 145         infostream << "RecursiveDelete: Deleting content of directory "
 146                         << path << std::endl;
 147         std::vector<DirListNode> content = GetDirListing(path);
 148         for (const DirListNode &n: content) {
 149                 std::string fullpath = path + DIR_DELIM + n.name;
 150                 if (!RecursiveDelete(fullpath)) {
 151                         errorstream << "RecursiveDelete: Failed to recurse to "
 152                                         << fullpath << std::endl;
 153                         return false;
 154                 }
 155         }
 156         infostream << "RecursiveDelete: Deleting directory " << path << std::endl;
 157         if (!RemoveDirectory(path.c_str())) {
 158                 errorstream << "Failed to recursively delete directory "
 159                                 << path << std::endl;
 160                 return false;
 161         }
 162         return true;
 163 }
 164
 165 bool DeleteSingleFileOrEmptyDirectory(const std::string &path)
 166 {
 167         DWORD attr = GetFileAttributes(path.c_str());
 168         bool is_directory = (attr != INVALID_FILE_ATTRIBUTES &&
 169                         (attr & FILE_ATTRIBUTE_DIRECTORY));
 170         if(!is_directory)
 171         {
 172                 bool did = DeleteFile(path.c_str());
 173                 return did;
 174         }
 175         else
 176         {
 177                 bool did = RemoveDirectory(path.c_str());
 178                 return did;
 179         }
 180 }
 181
 182 std::string TempPath()
 183 {
 184         DWORD bufsize = GetTempPath(0, NULL);
 185         if(bufsize == 0){
 186                 errorstream<<"GetTempPath failed, error = "<<GetLastError()<<std::endl;
 187                 return "";
 188         }
 189         std::string buf;
 190         buf.resize(bufsize);
 191         DWORD len = GetTempPath(bufsize, &buf[0]);
 192         if(len == 0 || len > bufsize){
 193                 errorstream<<"GetTempPath failed, error = "<<GetLastError()<<std::endl;
 194                 return "";
 195         }
 196         buf.resize(len);
 197         return buf;
 198 }
 199
 200 std::string CreateTempFile()
 201 {
 202         std::string path = TempPath() + DIR_DELIM "MT_XXXXXX";
 203         _mktemp_s(&path[0], path.size() + 1); // modifies path
 204         HANDLE file = CreateFile(path.c_str(), GENERIC_WRITE, 0, nullptr,
 205                 CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, nullptr);
 206         if (file == INVALID_HANDLE_VALUE)
 207                 return "";
 208         CloseHandle(file);
 209         return path;
 210 }
 211
 212 #else
 213
 214 /*********
 215  * POSIX *
 216  *********/
 217
 218 #include <sys/types.h>
 219 #include <dirent.h>
 220 #include <sys/stat.h>
 221 #include <sys/wait.h>
 222 #include <unistd.h>
 223
 224 std::vector<DirListNode> GetDirListing(const std::string &pathstring)
 225 {
 226         std::vector<DirListNode> listing;
 227
 228         DIR *dp;
 229         struct dirent *dirp;
 230         if((dp = opendir(pathstring.c_str())) == NULL) {
 231                 //infostream<<"Error("<<errno<<") opening "<<pathstring<<std::endl;
 232                 return listing;
 233         }
 234
 235         while ((dirp = readdir(dp)) != NULL) {
 236                 // NOTE:
 237                 // Be very sure to not include '..' in the results, it will
 238                 // result in an epic failure when deleting stuff.
 239                 if(strcmp(dirp->d_name, ".") == 0 || strcmp(dirp->d_name, "..") == 0)
 240                         continue;
 241
 242                 DirListNode node;
 243                 node.name = dirp->d_name;
 244
 245                 int isdir = -1; // -1 means unknown
 246
 247                 /*
 248                         POSIX doesn't define d_type member of struct dirent and
 249                         certain filesystems on glibc/Linux will only return
 250                         DT_UNKNOWN for the d_type member.
 251
 252                         Also we don't know whether symlinks are directories or not.
 253                 */
 254 #ifdef _DIRENT_HAVE_D_TYPE
 255                 if(dirp->d_type != DT_UNKNOWN && dirp->d_type != DT_LNK)
 256                         isdir = (dirp->d_type == DT_DIR);
 257 #endif /* _DIRENT_HAVE_D_TYPE */
 258
 259                 /*
 260                         Was d_type DT_UNKNOWN, DT_LNK or nonexistent?
 261                         If so, try stat().
 262                 */
 263                 if(isdir == -1) {
 264                         struct stat statbuf{};
 265                         if (stat((pathstring + "/" + node.name).c_str(), &statbuf))
 266                                 continue;
 267                         isdir = ((statbuf.st_mode & S_IFDIR) == S_IFDIR);
 268                 }
 269                 node.dir = isdir;
 270                 listing.push_back(node);
 271         }
 272         closedir(dp);
 273
 274         return listing;
 275 }
 276
 277 bool CreateDir(const std::string &path)
 278 {
 279         int r = mkdir(path.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
 280         if (r == 0) {
 281                 return true;
 282         }
 283
 284         // If already exists, return true
 285         if (errno == EEXIST)
 286                 return true;
 287         return false;
 288
 289 }
 290
 291 bool PathExists(const std::string &path)
 292 {
 293         struct stat st{};
 294         return (stat(path.c_str(),&st) == 0);
 295 }
 296
 297 bool IsPathAbsolute(const std::string &path)
 298 {
 299         return path[0] == '/';
 300 }
 301
 302 bool IsDir(const std::string &path)
 303 {
 304         struct stat statbuf{};
 305         if(stat(path.c_str(), &statbuf))
 306                 return false; // Actually error; but certainly not a directory
 307         return ((statbuf.st_mode & S_IFDIR) == S_IFDIR);
 308 }
 309
 310 bool IsDirDelimiter(char c)
 311 {
 312         return c == '/';
 313 }
 314
 315 bool RecursiveDelete(const std::string &path)
 316 {
 317         /*
 318                 Execute the 'rm' command directly, by fork() and execve()
 319         */
 320
 321         infostream<<"Removing \""<<path<<"\""<<std::endl;
 322
 323         pid_t child_pid = fork();
 324
 325         if(child_pid == 0)
 326         {
 327                 // Child
 328                 const char *argv[4] = {
 329 #ifdef __ANDROID__
 330                         "/system/bin/rm",
 331 #else
 332                         "/bin/rm",
 333 #endif
 334                         "-rf",
 335                         path.c_str(),
 336                         NULL
 337                 };
 338
 339                 verbosestream<<"Executing '"<<argv[0]<<"' '"<<argv[1]<<"' '"
 340                                 <<argv[2]<<"'"<<std::endl;
 341
 342                 execv(argv[0], const_cast<char**>(argv));
 343
 344                 // Execv shouldn't return. Failed.
 345                 _exit(1);
 346         }
 347         else
 348         {
 349                 // Parent
 350                 int child_status;
 351                 pid_t tpid;
 352                 do{
 353                         tpid = wait(&child_status);
 354                 }while(tpid != child_pid);
 355                 return (child_status == 0);
 356         }
 357 }
 358
 359 bool DeleteSingleFileOrEmptyDirectory(const std::string &path)
 360 {
 361         if (IsDir(path)) {
 362                 bool did = (rmdir(path.c_str()) == 0);
 363                 if (!did)
 364                         errorstream << "rmdir errno: " << errno << ": " << strerror(errno)
 365                                         << std::endl;
 366                 return did;
 367         }
 368
 369         bool did = (unlink(path.c_str()) == 0);
 370         if (!did)
 371                 errorstream << "unlink errno: " << errno << ": " << strerror(errno)
 372                                 << std::endl;
 373         return did;
 374 }
 375
 376 std::string TempPath()
 377 {
 378         /*
 379                 Should the environment variables TMPDIR, TMP and TEMP
 380                 and the macro P_tmpdir (if defined by stdio.h) be checked
 381                 before falling back on /tmp?
 382
 383                 Probably not, because this function is intended to be
 384                 compatible with lua's os.tmpname which under the default
 385                 configuration hardcodes mkstemp("/tmp/lua_XXXXXX").
 386         */
 387
 388 #ifdef __ANDROID__
 389         return porting::path_cache;
 390 #else
 391         return DIR_DELIM "tmp";
 392 #endif
 393 }
 394
 395 std::string CreateTempFile()
 396 {
 397         std::string path = TempPath() + DIR_DELIM "MT_XXXXXX";
 398         int fd = mkstemp(&path[0]); // modifies path
 399         if (fd == -1)
 400                 return "";
 401         close(fd);
 402         return path;
 403 }
 404
 405 #endif
 406
 407 /****************************
 408  * portable implementations *
 409  ****************************/
 410
 411 void GetRecursiveDirs(std::vector<std::string> &dirs, const std::string &dir)
 412 {
 413         static const std::set<char> chars_to_ignore = { '_', '.' };
 414         if (dir.empty() || !IsDir(dir))
 415                 return;
 416         dirs.push_back(dir);
 417         fs::GetRecursiveSubPaths(dir, dirs, false, chars_to_ignore);
 418 }
 419
 420 std::vector<std::string> GetRecursiveDirs(const std::string &dir)
 421 {
 422         std::vector<std::string> result;
 423         GetRecursiveDirs(result, dir);
 424         return result;
 425 }
 426
 427 void GetRecursiveSubPaths(const std::string &path,
 428                   std::vector<std::string> &dst,
 429                   bool list_files,
 430                   const std::set<char> &ignore)
 431 {
 432         std::vector<DirListNode> content = GetDirListing(path);
 433         for (const auto &n : content) {
 434                 std::string fullpath = path + DIR_DELIM + n.name;
 435                 if (ignore.count(n.name[0]))
 436                         continue;
 437                 if (list_files || n.dir)
 438                         dst.push_back(fullpath);
 439                 if (n.dir)
 440                         GetRecursiveSubPaths(fullpath, dst, list_files, ignore);
 441         }
 442 }
 443
 444 bool RecursiveDeleteContent(const std::string &path)
 445 {
 446         infostream<<"Removing content of \""<<path<<"\""<<std::endl;
 447         std::vector<DirListNode> list = GetDirListing(path);
 448         for (const DirListNode &dln : list) {
 449                 if(trim(dln.name) == "." || trim(dln.name) == "..")
 450                         continue;
 451                 std::string childpath = path + DIR_DELIM + dln.name;
 452                 bool r = RecursiveDelete(childpath);
 453                 if(!r) {
 454                         errorstream << "Removing \"" << childpath << "\" failed" << std::endl;
 455                         return false;
 456                 }
 457         }
 458         return true;
 459 }
 460
 461 bool CreateAllDirs(const std::string &path)
 462 {
 463
 464         std::vector<std::string> tocreate;
 465         std::string basepath = path;
 466         while(!PathExists(basepath))
 467         {
 468                 tocreate.push_back(basepath);
 469                 basepath = RemoveLastPathComponent(basepath);
 470                 if(basepath.empty())
 471                         break;
 472         }
 473         for(int i=tocreate.size()-1;i>=0;i--)
 474                 if(!CreateDir(tocreate[i]))
 475                         return false;
 476         return true;
 477 }
 478
 479 bool CopyFileContents(const std::string &source, const std::string &target)
 480 {
 481         FILE *sourcefile = fopen(source.c_str(), "rb");
 482         if(sourcefile == NULL){
 483                 errorstream<<source<<": can't open for reading: "
 484                         <<strerror(errno)<<std::endl;
 485                 return false;
 486         }
 487
 488         FILE *targetfile = fopen(target.c_str(), "wb");
 489         if(targetfile == NULL){
 490                 errorstream<<target<<": can't open for writing: "
 491                         <<strerror(errno)<<std::endl;
 492                 fclose(sourcefile);
 493                 return false;
 494         }
 495
 496         size_t total = 0;
 497         bool retval = true;
 498         bool done = false;
 499         char readbuffer[BUFSIZ];
 500         while(!done){
 501                 size_t readbytes = fread(readbuffer, 1,
 502                                 sizeof(readbuffer), sourcefile);
 503                 total += readbytes;
 504                 if(ferror(sourcefile)){
 505                         errorstream<<source<<": IO error: "
 506                                 <<strerror(errno)<<std::endl;
 507                         retval = false;
 508                         done = true;
 509                 }
 510                 if(readbytes > 0){
 511                         fwrite(readbuffer, 1, readbytes, targetfile);
 512                 }
 513                 if(feof(sourcefile) || ferror(sourcefile)){
 514                         // flush destination file to catch write errors
 515                         // (e.g. disk full)
 516                         fflush(targetfile);
 517                         done = true;
 518                 }
 519                 if(ferror(targetfile)){
 520                         errorstream<<target<<": IO error: "
 521                                         <<strerror(errno)<<std::endl;
 522                         retval = false;
 523                         done = true;
 524                 }
 525         }
 526         infostream<<"copied "<<total<<" bytes from "
 527                 <<source<<" to "<<target<<std::endl;
 528         fclose(sourcefile);
 529         fclose(targetfile);
 530         return retval;
 531 }
 532
 533 bool CopyDir(const std::string &source, const std::string &target)
 534 {
 535         if(PathExists(source)){
 536                 if(!PathExists(target)){
 537                         fs::CreateAllDirs(target);
 538                 }
 539                 bool retval = true;
 540                 std::vector<DirListNode> content = fs::GetDirListing(source);
 541
 542                 for (const auto &dln : content) {
 543                         std::string sourcechild = source + DIR_DELIM + dln.name;
 544                         std::string targetchild = target + DIR_DELIM + dln.name;
 545                         if(dln.dir){
 546                                 if(!fs::CopyDir(sourcechild, targetchild)){
 547                                         retval = false;
 548                                 }
 549                         }
 550                         else {
 551                                 if(!fs::CopyFileContents(sourcechild, targetchild)){
 552                                         retval = false;
 553                                 }
 554                         }
 555                 }
 556                 return retval;
 557         }
 558
 559         return false;
 560 }
 561
 562 bool MoveDir(const std::string &source, const std::string &target)
 563 {
 564         infostream << "Moving \"" << source << "\" to \"" << target << "\"" << std::endl;
 565
 566         // If target exists as empty folder delete, otherwise error
 567         if (fs::PathExists(target)) {
 568                 if (rmdir(target.c_str()) != 0) {
 569                         errorstream << "MoveDir: target \"" << target
 570                                 << "\" exists as file or non-empty folder" << std::endl;
 571                         return false;
 572                 }
 573         }
 574
 575         // Try renaming first which is instant
 576         if (fs::Rename(source, target))
 577                 return true;
 578
 579         infostream << "MoveDir: rename not possible, will copy instead" << std::endl;
 580         bool retval = fs::CopyDir(source, target);
 581         if (retval)
 582                 retval &= fs::RecursiveDelete(source);
 583         return retval;
 584 }
 585
 586 bool PathStartsWith(const std::string &path, const std::string &prefix)
 587 {
 588         size_t pathsize = path.size();
 589         size_t pathpos = 0;
 590         size_t prefixsize = prefix.size();
 591         size_t prefixpos = 0;
 592         for(;;){
 593                 bool delim1 = pathpos == pathsize
 594                         || IsDirDelimiter(path[pathpos]);
 595                 bool delim2 = prefixpos == prefixsize
 596                         || IsDirDelimiter(prefix[prefixpos]);
 597
 598                 if(delim1 != delim2)
 599                         return false;
 600
 601                 if(delim1){
 602                         while(pathpos < pathsize &&
 603                                         IsDirDelimiter(path[pathpos]))
 604                                 ++pathpos;
 605                         while(prefixpos < prefixsize &&
 606                                         IsDirDelimiter(prefix[prefixpos]))
 607                                 ++prefixpos;
 608                         if(prefixpos == prefixsize)
 609                                 return true;
 610                         if(pathpos == pathsize)
 611                                 return false;
 612                 }
 613                 else{
 614                         size_t len = 0;
 615                         do{
 616                                 char pathchar = path[pathpos+len];
 617                                 char prefixchar = prefix[prefixpos+len];
 618                                 if(FILESYS_CASE_INSENSITIVE){
 619                                         pathchar = tolower(pathchar);
 620                                         prefixchar = tolower(prefixchar);
 621                                 }
 622                                 if(pathchar != prefixchar)
 623                                         return false;
 624                                 ++len;
 625                         } while(pathpos+len < pathsize
 626                                         && !IsDirDelimiter(path[pathpos+len])
 627                                         && prefixpos+len < prefixsize
 628                                         && !IsDirDelimiter(
 629                                                 prefix[prefixpos+len]));
 630                         pathpos += len;
 631                         prefixpos += len;
 632                 }
 633         }
 634 }
 635
 636 std::string RemoveLastPathComponent(const std::string &path,
 637                 std::string *removed, int count)
 638 {
 639         if(removed)
 640                 *removed = "";
 641
 642         size_t remaining = path.size();
 643
 644         for(int i = 0; i < count; ++i){
 645                 // strip a dir delimiter
 646                 while(remaining != 0 && IsDirDelimiter(path[remaining-1]))
 647                         remaining--;
 648                 // strip a path component
 649                 size_t component_end = remaining;
 650                 while(remaining != 0 && !IsDirDelimiter(path[remaining-1]))
 651                         remaining--;
 652                 size_t component_start = remaining;
 653                 // strip a dir delimiter
 654                 while(remaining != 0 && IsDirDelimiter(path[remaining-1]))
 655                         remaining--;
 656                 if(removed){
 657                         std::string component = path.substr(component_start,
 658                                         component_end - component_start);
 659                         if(i)
 660                                 *removed = component + DIR_DELIM + *removed;
 661                         else
 662                                 *removed = component;
 663                 }
 664         }
 665         return path.substr(0, remaining);
 666 }
 667
 668 std::string RemoveRelativePathComponents(std::string path)
 669 {
 670         size_t pos = path.size();
 671         size_t dotdot_count = 0;
 672         while (pos != 0) {
 673                 size_t component_with_delim_end = pos;
 674                 // skip a dir delimiter
 675                 while (pos != 0 && IsDirDelimiter(path[pos-1]))
 676                         pos--;
 677                 // strip a path component
 678                 size_t component_end = pos;
 679                 while (pos != 0 && !IsDirDelimiter(path[pos-1]))
 680                         pos--;
 681                 size_t component_start = pos;
 682
 683                 std::string component = path.substr(component_start,
 684                                 component_end - component_start);
 685                 bool remove_this_component = false;
 686                 if (component == ".") {
 687                         remove_this_component = true;
 688                 } else if (component == "..") {
 689                         remove_this_component = true;
 690                         dotdot_count += 1;
 691                 } else if (dotdot_count != 0) {
 692                         remove_this_component = true;
 693                         dotdot_count -= 1;
 694                 }
 695
 696                 if (remove_this_component) {
 697                         while (pos != 0 && IsDirDelimiter(path[pos-1]))
 698                                 pos--;
 699                         if (component_start == 0) {
 700                                 // We need to remove the delemiter too
 701                                 path = path.substr(component_with_delim_end, std::string::npos);
 702                         } else {
 703                                 path = path.substr(0, pos) + DIR_DELIM +
 704                                         path.substr(component_with_delim_end, std::string::npos);
 705                         }
 706                         if (pos > 0)
 707                                 pos++;
 708                 }
 709         }
 710
 711         if (dotdot_count > 0)
 712                 return "";
 713
 714         // remove trailing dir delimiters
 715         pos = path.size();
 716         while (pos != 0 && IsDirDelimiter(path[pos-1]))
 717                 pos--;
 718         return path.substr(0, pos);
 719 }
 720
 721 std::string AbsolutePath(const std::string &path)
 722 {
 723 #ifdef _WIN32
 724         char *abs_path = _fullpath(NULL, path.c_str(), MAX_PATH);
 725 #else
 726         char *abs_path = realpath(path.c_str(), NULL);
 727 #endif
 728         if (!abs_path) return "";
 729         std::string abs_path_str(abs_path);
 730         free(abs_path);
 731         return abs_path_str;
 732 }
 733
 734 const char *GetFilenameFromPath(const char *path)
 735 {
 736         const char *filename = strrchr(path, DIR_DELIM_CHAR);
 737         // Consistent with IsDirDelimiter this function handles '/' too
 738         if (DIR_DELIM_CHAR != '/') {
 739                 const char *tmp = strrchr(path, '/');
 740                 if (tmp && tmp > filename)
 741                         filename = tmp;
 742         }
 743         return filename ? filename + 1 : path;
 744 }
 745
 746 bool safeWriteToFile(const std::string &path, const std::string &content)
 747 {
 748         std::string tmp_file = path + ".~mt";
 749
 750         // Write to a tmp file
 751         std::ofstream os(tmp_file.c_str(), std::ios::binary);
 752         if (!os.good())
 753                 return false;
 754         os << content;
 755         os.flush();
 756         os.close();
 757         if (os.fail()) {
 758                 // Remove the temporary file because writing it failed and it's useless.
 759                 remove(tmp_file.c_str());
 760                 return false;
 761         }
 762
 763         bool rename_success = false;
 764
 765         // Move the finished temporary file over the real file
 766 #ifdef _WIN32
 767         // When creating the file, it can cause Windows Search indexer, virus scanners and other apps
 768         // to query the file. This can make the move file call below fail.
 769         // We retry up to 5 times, with a 1ms sleep between, before we consider the whole operation failed
 770         int number_attempts = 0;
 771         while (number_attempts < 5) {
 772                 rename_success = MoveFileEx(tmp_file.c_str(), path.c_str(),
 773                                 MOVEFILE_REPLACE_EXISTING | MOVEFILE_WRITE_THROUGH);
 774                 if (rename_success)
 775                         break;
 776                 sleep_ms(1);
 777                 ++number_attempts;
 778         }
 779 #else
 780         // On POSIX compliant systems rename() is specified to be able to swap the
 781         // file in place of the destination file, making this a truly error-proof
 782         // transaction.
 783         rename_success = rename(tmp_file.c_str(), path.c_str()) == 0;
 784 #endif
 785         if (!rename_success) {
 786                 warningstream << "Failed to write to file: " << path.c_str() << std::endl;
 787                 // Remove the temporary file because moving it over the target file
 788                 // failed.
 789                 remove(tmp_file.c_str());
 790                 return false;
 791         }
 792
 793         return true;
 794 }
 795
 796 #ifndef SERVER
 797 bool extractZipFile(io::IFileSystem *fs, const char *filename, const std::string &destination)
 798 {
 799         // Be careful here not to touch the global file hierarchy in Irrlicht
 800         // since this function needs to be thread-safe!
 801
 802         io::IArchiveLoader *zip_loader = nullptr;
 803         for (u32 i = 0; i < fs->getArchiveLoaderCount(); i++) {
 804                 if (fs->getArchiveLoader(i)->isALoadableFileFormat(io::EFAT_ZIP)) {
 805                         zip_loader = fs->getArchiveLoader(i);
 806                         break;
 807                 }
 808         }
 809         if (!zip_loader) {
 810                 warningstream << "fs::extractZipFile(): Irrlicht said it doesn't support ZIPs." << std::endl;
 811                 return false;
 812         }
 813
 814         irr_ptr<io::IFileArchive> opened_zip(zip_loader->createArchive(filename, false, false));
 815         const io::IFileList* files_in_zip = opened_zip->getFileList();
 816
 817         for (u32 i = 0; i < files_in_zip->getFileCount(); i++) {
 818                 std::string fullpath = destination + DIR_DELIM;
 819                 fullpath += files_in_zip->getFullFileName(i).c_str();
 820                 std::string fullpath_dir = fs::RemoveLastPathComponent(fullpath);
 821
 822                 if (files_in_zip->isDirectory(i))
 823                         continue; // ignore, we create dirs as necessary
 824
 825                 if (!fs::PathExists(fullpath_dir) && !fs::CreateAllDirs(fullpath_dir))
 826                         return false;
 827
 828                 irr_ptr<io::IReadFile> toread(opened_zip->createAndOpenFile(i));
 829
 830                 std::ofstream os(fullpath.c_str(), std::ios::binary);
 831                 if (!os.good())
 832                         return false;
 833
 834                 char buffer[4096];
 835                 long total_read = 0;
 836
 837                 while (total_read < toread->getSize()) {
 838                         long bytes_read = toread->read(buffer, sizeof(buffer));
 839                         bool error = true;
 840                         if (bytes_read != 0) {
 841                                 os.write(buffer, bytes_read);
 842                                 error = os.fail();
 843                         }
 844                         if (error) {
 845                                 os.close();
 846                                 remove(fullpath.c_str());
 847                                 return false;
 848                         }
 849                         total_read += bytes_read;
 850                 }
 851         }
 852
 853         return true;
 854 }
 855 #endif
 856
 857 bool ReadFile(const std::string &path, std::string &out)
 858 {
 859         std::ifstream is(path, std::ios::binary | std::ios::ate);
 860         if (!is.good()) {
 861                 return false;
 862         }
 863
 864         auto size = is.tellg();
 865         out.resize(size);
 866         is.seekg(0);
 867         is.read(&out[0], size);
 868
 869         return !is.fail();
 870 }
 871
 872 bool Rename(const std::string &from, const std::string &to)
 873 {
 874         return rename(from.c_str(), to.c_str()) == 0;
 875 }
 876
 877 } // namespace fs
 878