pkgutil.cc

   1 //
   2 //  pkgutils
   3 //
   4 //  Copyright (c) 2000-2005 Per Liden
   5 //
   6 //  This program is free software; you can redistribute it and/or modify
   7 //  it under the terms of the GNU General Public License as published by
   8 //  the Free Software Foundation; either version 2 of the License, or
   9 //  (at your option) any later version.
  10 //
  11 //  This program is distributed in the hope that it will be useful,
  12 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 //  GNU General Public License for more details.
  15 //
  16 //  You should have received a copy of the GNU General Public License
  17 //  along with this program; if not, write to the Free Software
  18 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 //  USA.
  20 //
  21
  22 #include "pkgutil.h"
  23 #include <iostream>
  24 #include <fstream>
  25 #include <iterator>
  26 #include <algorithm>
  27 #include <cstdio>
  28 #include <cstring>
  29 #include <cerrno>
  30 #include <csignal>
  31 #include <ext/stdio_filebuf.h>
  32 #include <pwd.h>
  33 #include <grp.h>
  34 #include <sys/types.h>
  35 #include <sys/stat.h>
  36 #include <sys/wait.h>
  37 #include <sys/file.h>
  38 #include <sys/param.h>
  39 #include <unistd.h>
  40 #include <fcntl.h>
  41 #include <zlib.h>
  42 #include <libgen.h>
  43 #include <archive.h>
  44 #include <archive_entry.h>
  45
  46 using __gnu_cxx::stdio_filebuf;
  47
  48 pkgutil::pkgutil(const string& name)
  49         : utilname(name)
  50 {
  51         // Ignore signals
  52         struct sigaction sa;
  53         memset(&sa, 0, sizeof(sa));
  54         sa.sa_handler = SIG_IGN;
  55         sigaction(SIGHUP, &sa, 0);
  56         sigaction(SIGINT, &sa, 0);
  57         sigaction(SIGQUIT, &sa, 0);
  58         sigaction(SIGTERM, &sa, 0);
  59 }
  60
  61 void pkgutil::db_open(const string& path)
  62 {
  63         // Read database
  64         root = trim_filename(path + "/");
  65         const string filename = root + PKG_DB;
  66
  67         int fd = open(filename.c_str(), O_RDONLY);
  68         if (fd == -1)
  69                 throw runtime_error_with_errno("could not open " + filename);
  70
  71         stdio_filebuf<char> filebuf(fd, ios::in, getpagesize());
  72         istream in(&filebuf);
  73         if (!in)
  74                 throw runtime_error_with_errno("could not read " + filename);
  75
  76         while (!in.eof()) {
  77                 // Read record
  78                 string name;
  79                 pkginfo_t info;
  80                 getline(in, name);
  81                 getline(in, info.version);
  82                 for (;;) {
  83                         string file;
  84                         getline(in, file);
  85
  86                         if (file.empty())
  87                                 break; // End of record
  88
  89                         info.files.insert(info.files.end(), file);
  90                 }
  91                 if (!info.files.empty())
  92                         packages[name] = info;
  93         }
  94
  95 #ifndef NDEBUG
  96         cerr << packages.size() << " packages found in database" << endl;
  97 #endif
  98 }
  99
 100 void pkgutil::db_commit()
 101 {
 102         const string dbfilename = root + PKG_DB;
 103         const string dbfilename_new = dbfilename + ".incomplete_transaction";
 104         const string dbfilename_bak = dbfilename + ".backup";
 105
 106         // Remove failed transaction (if it exists)
 107         if (unlink(dbfilename_new.c_str()) == -1 && errno != ENOENT)
 108                 throw runtime_error_with_errno("could not remove " + dbfilename_new);
 109
 110         // Write new database
 111         int fd_new = creat(dbfilename_new.c_str(), 0444);
 112         if (fd_new == -1)
 113                 throw runtime_error_with_errno("could not create " + dbfilename_new);
 114
 115         stdio_filebuf<char> filebuf_new(fd_new, ios::out, getpagesize());
 116         ostream db_new(&filebuf_new);
 117         for (packages_t::const_iterator i = packages.begin(); i != packages.end(); ++i) {
 118                 if (!i->second.files.empty()) {
 119                         db_new << i->first << "\n";
 120                         db_new << i->second.version << "\n";
 121                         copy(i->second.files.begin(), i->second.files.end(), ostream_iterator<string>(db_new, "\n"));
 122                         db_new << "\n";
 123                 }
 124         }
 125
 126         db_new.flush();
 127
 128         // Make sure the new database was successfully written
 129         if (!db_new)
 130                 throw runtime_error("could not write " + dbfilename_new);
 131
 132         // Synchronize file to disk
 133         if (fsync(fd_new) == -1)
 134                 throw runtime_error_with_errno("could not synchronize " + dbfilename_new);
 135
 136         // Relink database backup
 137         if (unlink(dbfilename_bak.c_str()) == -1 && errno != ENOENT)
 138                 throw runtime_error_with_errno("could not remove " + dbfilename_bak);
 139         if (link(dbfilename.c_str(), dbfilename_bak.c_str()) == -1)
 140                 throw runtime_error_with_errno("could not create " + dbfilename_bak);
 141
 142         // Move new database into place
 143         if (rename(dbfilename_new.c_str(), dbfilename.c_str()) == -1)
 144                 throw runtime_error_with_errno("could not rename " + dbfilename_new + " to " + dbfilename);
 145
 146 #ifndef NDEBUG
 147         cerr << packages.size() << " packages written to database" << endl;
 148 #endif
 149 }
 150
 151 void pkgutil::db_add_pkg(const string& name, const pkginfo_t& info)
 152 {
 153         packages[name] = info;
 154 }
 155
 156 bool pkgutil::db_find_pkg(const string& name)
 157 {
 158         return (packages.find(name) != packages.end());
 159 }
 160
 161 void pkgutil::db_rm_pkg(const string& name)
 162 {
 163         set<string> files = packages[name].files;
 164         packages.erase(name);
 165
 166 #ifndef NDEBUG
 167         cerr << "Removing package phase 1 (all files in package):" << endl;
 168         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 169         cerr << endl;
 170 #endif
 171
 172         // Don't delete files that still have references
 173         for (packages_t::const_iterator i = packages.begin(); i != packages.end(); ++i)
 174                 for (set<string>::const_iterator j = i->second.files.begin(); j != i->second.files.end(); ++j)
 175                         files.erase(*j);
 176
 177 #ifndef NDEBUG
 178         cerr << "Removing package phase 2 (files that still have references excluded):" << endl;
 179         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 180         cerr << endl;
 181 #endif
 182
 183         // Delete the files
 184         for (set<string>::const_reverse_iterator i = files.rbegin(); i != files.rend(); ++i) {
 185                 const string filename = root + *i;
 186                 if (file_exists(filename) && remove(filename.c_str()) == -1) {
 187                         const char* msg = strerror(errno);
 188                         cerr << utilname << ": could not remove " << filename << ": " << msg << endl;
 189                 }
 190         }
 191 }
 192
 193 void pkgutil::db_rm_pkg(const string& name, const set<string>& keep_list)
 194 {
 195         set<string> files = packages[name].files;
 196         packages.erase(name);
 197
 198 #ifndef NDEBUG
 199         cerr << "Removing package phase 1 (all files in package):" << endl;
 200         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 201         cerr << endl;
 202 #endif
 203
 204         // Don't delete files found in the keep list
 205         for (set<string>::const_iterator i = keep_list.begin(); i != keep_list.end(); ++i)
 206                 files.erase(*i);
 207
 208 #ifndef NDEBUG
 209         cerr << "Removing package phase 2 (files that is in the keep list excluded):" << endl;
 210         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 211         cerr << endl;
 212 #endif
 213
 214         // Don't delete files that still have references
 215         for (packages_t::const_iterator i = packages.begin(); i != packages.end(); ++i)
 216                 for (set<string>::const_iterator j = i->second.files.begin(); j != i->second.files.end(); ++j)
 217                         files.erase(*j);
 218
 219 #ifndef NDEBUG
 220         cerr << "Removing package phase 3 (files that still have references excluded):" << endl;
 221         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 222         cerr << endl;
 223 #endif
 224
 225         // Delete the files
 226         for (set<string>::const_reverse_iterator i = files.rbegin(); i != files.rend(); ++i) {
 227                 const string filename = root + *i;
 228                 if (file_exists(filename) && remove(filename.c_str()) == -1) {
 229                         if (errno == ENOTEMPTY)
 230                                 continue;
 231                         const char* msg = strerror(errno);
 232                         cerr << utilname << ": could not remove " << filename << ": " << msg << endl;
 233                 }
 234         }
 235 }
 236
 237 void pkgutil::db_rm_files(set<string> files, const set<string>& keep_list)
 238 {
 239         // Remove all references
 240         for (packages_t::iterator i = packages.begin(); i != packages.end(); ++i)
 241                 for (set<string>::const_iterator j = files.begin(); j != files.end(); ++j)
 242                         i->second.files.erase(*j);
 243
 244 #ifndef NDEBUG
 245         cerr << "Removing files:" << endl;
 246         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 247         cerr << endl;
 248 #endif
 249
 250         // Don't delete files found in the keep list
 251         for (set<string>::const_iterator i = keep_list.begin(); i != keep_list.end(); ++i)
 252                 files.erase(*i);
 253
 254         // Delete the files
 255         for (set<string>::const_reverse_iterator i = files.rbegin(); i != files.rend(); ++i) {
 256                 const string filename = root + *i;
 257                 if (file_exists(filename) && remove(filename.c_str()) == -1) {
 258                         if (errno == ENOTEMPTY)
 259                                 continue;
 260                         const char* msg = strerror(errno);
 261                         cerr << utilname << ": could not remove " << filename << ": " << msg << endl;
 262                 }
 263         }
 264 }
 265
 266 set<string> pkgutil::db_find_conflicts(const string& name, const pkginfo_t& info)
 267 {
 268         set<string> files;
 269
 270         // Find conflicting files in database
 271         for (packages_t::const_iterator i = packages.begin(); i != packages.end(); ++i) {
 272                 if (i->first != name) {
 273                         set_intersection(info.files.begin(), info.files.end(),
 274                                          i->second.files.begin(), i->second.files.end(),
 275                                          inserter(files, files.end()));
 276                 }
 277         }
 278
 279 #ifndef NDEBUG
 280         cerr << "Conflicts phase 1 (conflicts in database):" << endl;
 281         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 282         cerr << endl;
 283 #endif
 284
 285         // Find conflicting files in filesystem
 286         for (set<string>::iterator i = info.files.begin(); i != info.files.end(); ++i) {
 287                 const string filename = root + *i;
 288                 if (file_exists(filename) && files.find(*i) == files.end())
 289                         files.insert(files.end(), *i);
 290         }
 291
 292 #ifndef NDEBUG
 293         cerr << "Conflicts phase 2 (conflicts in filesystem added):" << endl;
 294         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 295         cerr << endl;
 296 #endif
 297
 298         // Exclude directories
 299         set<string> tmp = files;
 300         for (set<string>::const_iterator i = tmp.begin(); i != tmp.end(); ++i) {
 301                 if ((*i)[i->length() - 1] == '/')
 302                         files.erase(*i);
 303         }
 304
 305 #ifndef NDEBUG
 306         cerr << "Conflicts phase 3 (directories excluded):" << endl;
 307         copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 308         cerr << endl;
 309 #endif
 310
 311         // If this is an upgrade, remove files already owned by this package
 312         if (packages.find(name) != packages.end()) {
 313                 for (set<string>::const_iterator i = packages[name].files.begin(); i != packages[name].files.end(); ++i)
 314                         files.erase(*i);
 315
 316 #ifndef NDEBUG
 317                 cerr << "Conflicts phase 4 (files already owned by this package excluded):" << endl;
 318                 copy(files.begin(), files.end(), ostream_iterator<string>(cerr, "\n"));
 319                 cerr << endl;
 320 #endif
 321         }
 322
 323         return files;
 324 }
 325
 326 pair<string, pkgutil::pkginfo_t> pkgutil::pkg_open(const string& filename) const
 327 {
 328         pair<string, pkginfo_t> result;
 329         unsigned int i;
 330         struct archive* archive;
 331         struct archive_entry* entry;
 332
 333         // Extract name and version from filename
 334         string basename(filename, filename.rfind('/') + 1);
 335         string name(basename, 0, basename.find(VERSION_DELIM));
 336         string version(basename, 0, basename.rfind(PKG_EXT));
 337         version.erase(0, version.find(VERSION_DELIM) == string::npos ? string::npos : version.find(VERSION_DELIM) + 1);
 338
 339         if (name.empty() || version.empty())
 340                 throw runtime_error("could not determine name and/or version of " + basename + ": Invalid package name");
 341
 342         result.first = name;
 343         result.second.version = version;
 344
 345         archive = archive_read_new();
 346         archive_read_support_compression_all(archive);
 347         archive_read_support_format_all(archive);
 348
 349         if (archive_read_open_filename(archive,
 350             const_cast<char*>(filename.c_str()),
 351             ARCHIVE_DEFAULT_BYTES_PER_BLOCK) != ARCHIVE_OK)
 352                 throw runtime_error_with_errno("could not open " + filename, archive_errno(archive));
 353
 354         for (i = 0; archive_read_next_header(archive, &entry) ==
 355              ARCHIVE_OK; ++i) {
 356                 const struct stat* status;
 357
 358                 result.second.files.insert(result.second.files.end(),
 359                                            archive_entry_pathname(entry));
 360
 361                 status = archive_entry_stat(entry);
 362
 363                 if (S_ISREG(status->st_mode) &&
 364                     archive_read_data_skip(archive) != ARCHIVE_OK)
 365                         throw runtime_error_with_errno("could not read " + filename, archive_errno(archive));
 366         }
 367
 368         if (i == 0) {
 369                 if (archive_errno(archive) == 0)
 370                         throw runtime_error("empty package");
 371                 else
 372                         throw runtime_error("could not read " + filename);
 373         }
 374
 375         archive_read_finish(archive);
 376
 377         return result;
 378 }
 379
 380 void pkgutil::pkg_install(const string& filename, const set<string>& keep_list, const set<string>& non_install_list) const
 381 {
 382         struct archive* archive;
 383         struct archive_entry* entry;
 384         unsigned int i;
 385
 386         archive = archive_read_new();
 387         archive_read_support_compression_all(archive);
 388         archive_read_support_format_all(archive);
 389
 390         if (archive_read_open_filename(archive,
 391             const_cast<char*>(filename.c_str()),
 392             ARCHIVE_DEFAULT_BYTES_PER_BLOCK) != ARCHIVE_OK)
 393                 throw runtime_error_with_errno("could not open " + filename, archive_errno(archive));
 394
 395         chdir(root.c_str());
 396
 397         for (i = 0; archive_read_next_header(archive, &entry) ==
 398              ARCHIVE_OK; ++i) {
 399                 string archive_filename = archive_entry_pathname(entry);
 400                 string reject_dir = trim_filename(root + string("/") + string(PKG_REJECTED));
 401                 string original_filename = trim_filename(root + string("/") + archive_filename);
 402                 string real_filename = original_filename;
 403
 404                 // Check if file is filtered out via INSTALL
 405                 if (non_install_list.find(archive_filename) != non_install_list.end()) {
 406                         const struct stat* status;
 407
 408                         cout << utilname << ": ignoring " << archive_filename << endl;
 409
 410                         status = archive_entry_stat(entry);
 411
 412                         if (S_ISREG(status->st_mode))
 413                                 archive_read_data_skip(archive);
 414
 415                         continue;
 416                 }
 417
 418                 // Check if file should be rejected
 419                 if (file_exists(real_filename) && keep_list.find(archive_filename) != keep_list.end())
 420                         real_filename = trim_filename(reject_dir + string("/") + archive_filename);
 421
 422                 archive_entry_set_pathname(entry, const_cast<char*>
 423                                            (real_filename.c_str()));
 424
 425                 // Extract file
 426                 if (archive_read_extract(archive, entry, 0) !=
 427                     ARCHIVE_OK) {
 428                         // If a file fails to install we just print an error message and
 429                         // continue trying to install the rest of the package.
 430                         const char* msg = archive_error_string(archive);
 431                         cerr << utilname << ": could not install " + archive_filename << ": " << msg << endl;
 432                         continue;
 433                 }
 434
 435                 // Check rejected file
 436                 if (real_filename != original_filename) {
 437                         bool remove_file = false;
 438                         const struct stat* status;
 439
 440                         status = archive_entry_stat(entry);
 441
 442                         // Directory
 443                         if (S_ISDIR(status->st_mode))
 444                                 remove_file = permissions_equal(real_filename, original_filename);
 445                         // Other files
 446                         else
 447                                 remove_file = permissions_equal(real_filename, original_filename) &&
 448                                         (file_empty(real_filename) || file_equal(real_filename, original_filename));
 449
 450                         // Remove rejected file or signal about its existence
 451                         if (remove_file)
 452                                 file_remove(reject_dir, real_filename);
 453                         else
 454                                 cout << utilname << ": rejecting " << archive_filename << ", keeping existing version" << endl;
 455                 }
 456         }
 457
 458         if (i == 0) {
 459                 if (archive_errno(archive) == 0)
 460                         throw runtime_error("empty package");
 461                 else
 462                         throw runtime_error("could not read " + filename);
 463         }
 464
 465         archive_read_finish(archive);
 466 }
 467
 468 void pkgutil::ldconfig() const
 469 {
 470         // Only execute ldconfig if /etc/ld.so.conf exists
 471         if (file_exists(root + LDCONFIG_CONF)) {
 472                 pid_t pid = fork();
 473
 474                 if (pid == -1)
 475                         throw runtime_error_with_errno("fork() failed");
 476
 477                 if (pid == 0) {
 478                         execl(LDCONFIG, LDCONFIG, "-r", root.c_str(), (char *) 0);
 479                         const char* msg = strerror(errno);
 480                         cerr << utilname << ": could not execute " << LDCONFIG << ": " << msg << endl;
 481                         exit(EXIT_FAILURE);
 482                 } else {
 483                         if (waitpid(pid, 0, 0) == -1)
 484                                 throw runtime_error_with_errno("waitpid() failed");
 485                 }
 486         }
 487 }
 488
 489 void pkgutil::pkg_footprint(string& filename) const
 490 {
 491         unsigned int i;
 492         struct archive* archive;
 493         struct archive_entry* entry;
 494
 495         archive = archive_read_new();
 496         archive_read_support_compression_all(archive);
 497         archive_read_support_format_all(archive);
 498
 499         if (archive_read_open_filename(archive,
 500             const_cast<char*>(filename.c_str()),
 501             ARCHIVE_DEFAULT_BYTES_PER_BLOCK) != ARCHIVE_OK)
 502                 throw runtime_error_with_errno("could not open " + filename, archive_errno(archive));
 503
 504         for (i = 0; archive_read_next_header(archive, &entry) ==
 505              ARCHIVE_OK; ++i) {
 506                 const struct stat* status;
 507
 508                 status = archive_entry_stat(entry);
 509
 510                 // Access permissions
 511                 if (S_ISLNK(status->st_mode)) {
 512                         // Access permissions on symlinks differ among filesystems, e.g. XFS and ext2 have different.
 513                         // To avoid getting different footprints we always use "lrwxrwxrwx".
 514                         cout << "lrwxrwxrwx";
 515                 } else {
 516                         cout << mtos(archive_entry_mode(entry));
 517                 }
 518
 519                 cout << '\t';
 520
 521                 // User
 522                 uid_t uid = archive_entry_uid(entry);
 523                 struct passwd* pw = getpwuid(uid);
 524                 if (pw)
 525                         cout << pw->pw_name;
 526                 else
 527                         cout << uid;
 528
 529                 cout << '/';
 530
 531                 // Group
 532                 gid_t gid = archive_entry_gid(entry);
 533                 struct group* gr = getgrgid(gid);
 534                 if (gr)
 535                         cout << gr->gr_name;
 536                 else
 537                         cout << gid;
 538
 539                 // Filename
 540                 cout << '\t' << archive_entry_pathname(entry);
 541
 542                 // Special cases
 543                 if (S_ISLNK(status->st_mode)) {
 544                         // Symlink
 545                         cout << " -> " << archive_entry_symlink(entry);
 546                 } else if (S_ISCHR(status->st_mode) ||
 547                            S_ISBLK(status->st_mode)) {
 548                         // Device
 549                         cout << " (" << archive_entry_rdevmajor(entry)
 550                              << ", " << archive_entry_rdevminor(entry)
 551                              << ")";
 552                 } else if (S_ISREG(status->st_mode) &&
 553                            archive_entry_size(entry) == 0) {
 554                         // Empty regular file
 555                         cout << " (EMPTY)";
 556                 }
 557
 558                 cout << '\n';
 559
 560                 if (S_ISREG(status->st_mode) && archive_read_data_skip(archive))
 561                         throw runtime_error_with_errno("could not read " + filename, archive_errno(archive));
 562         }
 563
 564         if (i == 0) {
 565                 if (archive_errno(archive) == 0)
 566                         throw runtime_error("empty package");
 567                 else
 568                         throw runtime_error("could not read " + filename);
 569         }
 570
 571         archive_read_finish(archive);
 572 }
 573
 574 void pkgutil::print_version() const
 575 {
 576         cout << utilname << " (pkgutils) " << VERSION << endl;
 577 }
 578
 579 db_lock::db_lock(const string& root, bool exclusive)
 580         : dir(0)
 581 {
 582         const string dirname = trim_filename(root + string("/") + PKG_DIR);
 583
 584         if (!(dir = opendir(dirname.c_str())))
 585                 throw runtime_error_with_errno("could not read directory " + dirname);
 586
 587         if (flock(dirfd(dir), (exclusive ? LOCK_EX : LOCK_SH) | LOCK_NB) == -1) {
 588                 if (errno == EWOULDBLOCK)
 589                         throw runtime_error("package database is currently locked by another process");
 590                 else
 591                         throw runtime_error_with_errno("could not lock directory " + dirname);
 592         }
 593 }
 594
 595 db_lock::~db_lock()
 596 {
 597         if (dir) {
 598                 flock(dirfd(dir), LOCK_UN);
 599                 closedir(dir);
 600         }
 601 }
 602
 603 void assert_argument(char** argv, int argc, int index)
 604 {
 605         if (argc - 1 < index + 1)
 606                 throw runtime_error("option " + string(argv[index]) + " requires an argument");
 607 }
 608
 609 string itos(unsigned int value)
 610 {
 611         static char buf[20];
 612         sprintf(buf, "%u", value);
 613         return buf;
 614 }
 615
 616 string mtos(mode_t mode)
 617 {
 618         string s;
 619
 620         // File type
 621         switch (mode & S_IFMT) {
 622         case S_IFREG:  s += '-'; break; // Regular
 623         case S_IFDIR:  s += 'd'; break; // Directory
 624         case S_IFLNK:  s += 'l'; break; // Symbolic link
 625         case S_IFCHR:  s += 'c'; break; // Character special
 626         case S_IFBLK:  s += 'b'; break; // Block special
 627         case S_IFSOCK: s += 's'; break; // Socket
 628         case S_IFIFO:  s += 'p'; break; // Fifo
 629         default:       s += '?'; break; // Unknown
 630         }
 631
 632         // User permissions
 633         s += (mode & S_IRUSR) ? 'r' : '-';
 634         s += (mode & S_IWUSR) ? 'w' : '-';
 635         switch (mode & (S_IXUSR | S_ISUID)) {
 636         case S_IXUSR:           s += 'x'; break;
 637         case S_ISUID:           s += 'S'; break;
 638         case S_IXUSR | S_ISUID: s += 's'; break;
 639         default:                s += '-'; break;
 640         }
 641
 642         // Group permissions
 643         s += (mode & S_IRGRP) ? 'r' : '-';
 644         s += (mode & S_IWGRP) ? 'w' : '-';
 645         switch (mode & (S_IXGRP | S_ISGID)) {
 646         case S_IXGRP:           s += 'x'; break;
 647         case S_ISGID:           s += 'S'; break;
 648         case S_IXGRP | S_ISGID: s += 's'; break;
 649         default:                s += '-'; break;
 650         }
 651
 652         // Other permissions
 653         s += (mode & S_IROTH) ? 'r' : '-';
 654         s += (mode & S_IWOTH) ? 'w' : '-';
 655         switch (mode & (S_IXOTH | S_ISVTX)) {
 656         case S_IXOTH:           s += 'x'; break;
 657         case S_ISVTX:           s += 'T'; break;
 658         case S_IXOTH | S_ISVTX: s += 't'; break;
 659         default:                s += '-'; break;
 660         }
 661
 662         return s;
 663 }
 664
 665 int unistd_gzopen(char* pathname, int flags, mode_t mode)
 666 {
 667         char* gz_mode;
 668
 669         switch (flags & O_ACCMODE) {
 670         case O_WRONLY:
 671                 gz_mode = "w";
 672                 break;
 673
 674         case O_RDONLY:
 675                 gz_mode = "r";
 676                 break;
 677
 678         case O_RDWR:
 679         default:
 680                 errno = EINVAL;
 681                 return -1;
 682         }
 683
 684         int fd;
 685         gzFile gz_file;
 686
 687         if ((fd = open(pathname, flags, mode)) == -1)
 688                 return -1;
 689
 690         if ((flags & O_CREAT) && fchmod(fd, mode))
 691                 return -1;
 692
 693         if (!(gz_file = gzdopen(fd, gz_mode))) {
 694                 errno = ENOMEM;
 695                 return -1;
 696         }
 697
 698         return (int)gz_file;
 699 }
 700
 701 string trim_filename(const string& filename)
 702 {
 703         string search("//");
 704         string result = filename;
 705
 706         for (string::size_type pos = result.find(search); pos != string::npos; pos = result.find(search))
 707                 result.replace(pos, search.size(), "/");
 708
 709         return result;
 710 }
 711
 712 bool file_exists(const string& filename)
 713 {
 714         struct stat buf;
 715         return !lstat(filename.c_str(), &buf);
 716 }
 717
 718 bool file_empty(const string& filename)
 719 {
 720         struct stat buf;
 721
 722         if (lstat(filename.c_str(), &buf) == -1)
 723                 return false;
 724
 725         return (S_ISREG(buf.st_mode) && buf.st_size == 0);
 726 }
 727
 728 bool file_equal(const string& file1, const string& file2)
 729 {
 730         struct stat buf1, buf2;
 731
 732         if (lstat(file1.c_str(), &buf1) == -1)
 733                 return false;
 734
 735         if (lstat(file2.c_str(), &buf2) == -1)
 736                 return false;
 737
 738         // Regular files
 739         if (S_ISREG(buf1.st_mode) && S_ISREG(buf2.st_mode)) {
 740                 ifstream f1(file1.c_str());
 741                 ifstream f2(file2.c_str());
 742
 743                 if (!f1 || !f2)
 744                         return false;
 745
 746                 while (!f1.eof()) {
 747                         char buffer1[4096];
 748                         char buffer2[4096];
 749                         f1.read(buffer1, 4096);
 750                         f2.read(buffer2, 4096);
 751                         if (f1.gcount() != f2.gcount() ||
 752                             memcmp(buffer1, buffer2, f1.gcount()) ||
 753                             f1.eof() != f2.eof())
 754                                 return false;
 755                 }
 756
 757                 return true;
 758         }
 759         // Symlinks
 760         else if (S_ISLNK(buf1.st_mode) && S_ISLNK(buf2.st_mode)) {
 761                 char symlink1[MAXPATHLEN];
 762                 char symlink2[MAXPATHLEN];
 763
 764                 memset(symlink1, 0, MAXPATHLEN);
 765                 memset(symlink2, 0, MAXPATHLEN);
 766
 767                 if (readlink(file1.c_str(), symlink1, MAXPATHLEN - 1) == -1)
 768                         return false;
 769
 770                 if (readlink(file2.c_str(), symlink2, MAXPATHLEN - 1) == -1)
 771                         return false;
 772
 773                 return !strncmp(symlink1, symlink2, MAXPATHLEN);
 774         }
 775         // Character devices
 776         else if (S_ISCHR(buf1.st_mode) && S_ISCHR(buf2.st_mode)) {
 777                 return buf1.st_dev == buf2.st_dev;
 778         }
 779         // Block devices
 780         else if (S_ISBLK(buf1.st_mode) && S_ISBLK(buf2.st_mode)) {
 781                 return buf1.st_dev == buf2.st_dev;
 782         }
 783
 784         return false;
 785 }
 786
 787 bool permissions_equal(const string& file1, const string& file2)
 788 {
 789         struct stat buf1;
 790         struct stat buf2;
 791
 792         if (lstat(file1.c_str(), &buf1) == -1)
 793                 return false;
 794
 795         if (lstat(file2.c_str(), &buf2) == -1)
 796                 return false;
 797
 798         return(buf1.st_mode == buf2.st_mode) &&
 799                 (buf1.st_uid == buf2.st_uid) &&
 800                 (buf1.st_gid == buf2.st_gid);
 801 }
 802
 803 void file_remove(const string& basedir, const string& filename)
 804 {
 805         if (filename != basedir && !remove(filename.c_str())) {
 806                 char* path = strdup(filename.c_str());
 807                 file_remove(basedir, dirname(path));
 808                 free(path);
 809         }
 810 }