arch/um/os-Linux/file.c

   1 /*
   2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <stdio.h>
   7 #include <unistd.h>
   8 #include <errno.h>
   9 #include <fcntl.h>
  10 #include <signal.h>
  11 #include <sys/ioctl.h>
  12 #include <sys/mount.h>
  13 #include <sys/socket.h>
  14 #include <sys/stat.h>
  15 #include <sys/sysmacros.h>
  16 #include <sys/un.h>
  17 #include <sys/types.h>
  18 #include <os.h>
  19
  20 static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
  21 {
  22         *dst = ((struct uml_stat) {
  23                 .ust_dev     = src->st_dev,     /* device */
  24                 .ust_ino     = src->st_ino,     /* inode */
  25                 .ust_mode    = src->st_mode,    /* protection */
  26                 .ust_nlink   = src->st_nlink,   /* number of hard links */
  27                 .ust_uid     = src->st_uid,     /* user ID of owner */
  28                 .ust_gid     = src->st_gid,     /* group ID of owner */
  29                 .ust_size    = src->st_size,    /* total size, in bytes */
  30                 .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
  31                 .ust_blocks  = src->st_blocks,  /* number of blocks allocated */
  32                 .ust_atime   = src->st_atime,   /* time of last access */
  33                 .ust_mtime   = src->st_mtime,   /* time of last modification */
  34                 .ust_ctime   = src->st_ctime,   /* time of last change */
  35         });
  36 }
  37
  38 int os_stat_fd(const int fd, struct uml_stat *ubuf)
  39 {
  40         struct stat64 sbuf;
  41         int err;
  42
  43         CATCH_EINTR(err = fstat64(fd, &sbuf));
  44         if (err < 0)
  45                 return -errno;
  46
  47         if (ubuf != NULL)
  48                 copy_stat(ubuf, &sbuf);
  49         return err;
  50 }
  51
  52 int os_stat_file(const char *file_name, struct uml_stat *ubuf)
  53 {
  54         struct stat64 sbuf;
  55         int err;
  56
  57         CATCH_EINTR(err = stat64(file_name, &sbuf));
  58         if (err < 0)
  59                 return -errno;
  60
  61         if (ubuf != NULL)
  62                 copy_stat(ubuf, &sbuf);
  63         return err;
  64 }
  65
  66 int os_access(const char *file, int mode)
  67 {
  68         int amode, err;
  69
  70         amode = (mode & OS_ACC_R_OK ? R_OK : 0) |
  71                 (mode & OS_ACC_W_OK ? W_OK : 0) |
  72                 (mode & OS_ACC_X_OK ? X_OK : 0) |
  73                 (mode & OS_ACC_F_OK ? F_OK : 0);
  74
  75         err = access(file, amode);
  76         if (err < 0)
  77                 return -errno;
  78
  79         return 0;
  80 }
  81
  82 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
  83 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
  84 {
  85         int err;
  86
  87         err = ioctl(fd, cmd, arg);
  88         if (err < 0)
  89                 return -errno;
  90
  91         return err;
  92 }
  93
  94 /* FIXME: ensure namebuf in os_get_if_name is big enough */
  95 int os_get_ifname(int fd, char* namebuf)
  96 {
  97         if (ioctl(fd, SIOCGIFNAME, namebuf) < 0)
  98                 return -errno;
  99
 100         return 0;
 101 }
 102
 103 int os_set_slip(int fd)
 104 {
 105         int disc, sencap;
 106
 107         disc = N_SLIP;
 108         if (ioctl(fd, TIOCSETD, &disc) < 0)
 109                 return -errno;
 110
 111         sencap = 0;
 112         if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
 113                 return -errno;
 114
 115         return 0;
 116 }
 117
 118 int os_mode_fd(int fd, int mode)
 119 {
 120         int err;
 121
 122         CATCH_EINTR(err = fchmod(fd, mode));
 123         if (err < 0)
 124                 return -errno;
 125
 126         return 0;
 127 }
 128
 129 int os_file_type(char *file)
 130 {
 131         struct uml_stat buf;
 132         int err;
 133
 134         err = os_stat_file(file, &buf);
 135         if (err < 0)
 136                 return err;
 137
 138         if (S_ISDIR(buf.ust_mode))
 139                 return OS_TYPE_DIR;
 140         else if (S_ISLNK(buf.ust_mode))
 141                 return OS_TYPE_SYMLINK;
 142         else if (S_ISCHR(buf.ust_mode))
 143                 return OS_TYPE_CHARDEV;
 144         else if (S_ISBLK(buf.ust_mode))
 145                 return OS_TYPE_BLOCKDEV;
 146         else if (S_ISFIFO(buf.ust_mode))
 147                 return OS_TYPE_FIFO;
 148         else if (S_ISSOCK(buf.ust_mode))
 149                 return OS_TYPE_SOCK;
 150         else return OS_TYPE_FILE;
 151 }
 152
 153 int os_file_mode(const char *file, struct openflags *mode_out)
 154 {
 155         int err;
 156
 157         *mode_out = OPENFLAGS();
 158
 159         err = access(file, W_OK);
 160         if (err && (errno != EACCES))
 161                 return -errno;
 162         else if (!err)
 163                 *mode_out = of_write(*mode_out);
 164
 165         err = access(file, R_OK);
 166         if (err && (errno != EACCES))
 167                 return -errno;
 168         else if (!err)
 169                 *mode_out = of_read(*mode_out);
 170
 171         return err;
 172 }
 173
 174 int os_open_file(const char *file, struct openflags flags, int mode)
 175 {
 176         int fd, err, f = 0;
 177
 178         if (flags.r && flags.w)
 179                 f = O_RDWR;
 180         else if (flags.r)
 181                 f = O_RDONLY;
 182         else if (flags.w)
 183                 f = O_WRONLY;
 184         else f = 0;
 185
 186         if (flags.s)
 187                 f |= O_SYNC;
 188         if (flags.c)
 189                 f |= O_CREAT;
 190         if (flags.t)
 191                 f |= O_TRUNC;
 192         if (flags.e)
 193                 f |= O_EXCL;
 194         if (flags.a)
 195                 f |= O_APPEND;
 196
 197         fd = open64(file, f, mode);
 198         if (fd < 0)
 199                 return -errno;
 200
 201         if (flags.cl && fcntl(fd, F_SETFD, 1)) {
 202                 err = -errno;
 203                 close(fd);
 204                 return err;
 205         }
 206
 207         return fd;
 208 }
 209
 210 int os_connect_socket(const char *name)
 211 {
 212         struct sockaddr_un sock;
 213         int fd, err;
 214
 215         sock.sun_family = AF_UNIX;
 216         snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
 217
 218         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 219         if (fd < 0) {
 220                 err = -errno;
 221                 goto out;
 222         }
 223
 224         err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
 225         if (err) {
 226                 err = -errno;
 227                 goto out_close;
 228         }
 229
 230         return fd;
 231
 232 out_close:
 233         close(fd);
 234 out:
 235         return err;
 236 }
 237
 238 void os_close_file(int fd)
 239 {
 240         close(fd);
 241 }
 242 int os_fsync_file(int fd)
 243 {
 244         if (fsync(fd) < 0)
 245             return -errno;
 246         return 0;
 247 }
 248
 249 int os_seek_file(int fd, unsigned long long offset)
 250 {
 251         unsigned long long actual;
 252
 253         actual = lseek64(fd, offset, SEEK_SET);
 254         if (actual != offset)
 255                 return -errno;
 256         return 0;
 257 }
 258
 259 int os_read_file(int fd, void *buf, int len)
 260 {
 261         int n = read(fd, buf, len);
 262
 263         if (n < 0)
 264                 return -errno;
 265         return n;
 266 }
 267
 268 int os_pread_file(int fd, void *buf, int len, unsigned long long offset)
 269 {
 270         int n = pread(fd, buf, len, offset);
 271
 272         if (n < 0)
 273                 return -errno;
 274         return n;
 275 }
 276
 277 int os_write_file(int fd, const void *buf, int len)
 278 {
 279         int n = write(fd, (void *) buf, len);
 280
 281         if (n < 0)
 282                 return -errno;
 283         return n;
 284 }
 285
 286 int os_sync_file(int fd)
 287 {
 288         int n = fsync(fd);
 289
 290         if (n < 0)
 291                 return -errno;
 292         return n;
 293 }
 294
 295 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset)
 296 {
 297         int n = pwrite(fd, (void *) buf, len, offset);
 298
 299         if (n < 0)
 300                 return -errno;
 301         return n;
 302 }
 303
 304
 305 int os_file_size(const char *file, unsigned long long *size_out)
 306 {
 307         struct uml_stat buf;
 308         int err;
 309
 310         err = os_stat_file(file, &buf);
 311         if (err < 0) {
 312                 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
 313                        -err);
 314                 return err;
 315         }
 316
 317         if (S_ISBLK(buf.ust_mode)) {
 318                 int fd;
 319                 long blocks;
 320
 321                 fd = open(file, O_RDONLY, 0);
 322                 if (fd < 0) {
 323                         err = -errno;
 324                         printk(UM_KERN_ERR "Couldn't open \"%s\", "
 325                                "errno = %d\n", file, errno);
 326                         return err;
 327                 }
 328                 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) {
 329                         err = -errno;
 330                         printk(UM_KERN_ERR "Couldn't get the block size of "
 331                                "\"%s\", errno = %d\n", file, errno);
 332                         close(fd);
 333                         return err;
 334                 }
 335                 *size_out = ((long long) blocks) * 512;
 336                 close(fd);
 337         }
 338         else *size_out = buf.ust_size;
 339
 340         return 0;
 341 }
 342
 343 int os_file_modtime(const char *file, unsigned long *modtime)
 344 {
 345         struct uml_stat buf;
 346         int err;
 347
 348         err = os_stat_file(file, &buf);
 349         if (err < 0) {
 350                 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file,
 351                        -err);
 352                 return err;
 353         }
 354
 355         *modtime = buf.ust_mtime;
 356         return 0;
 357 }
 358
 359 int os_set_exec_close(int fd)
 360 {
 361         int err;
 362
 363         CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));
 364
 365         if (err < 0)
 366                 return -errno;
 367         return err;
 368 }
 369
 370 int os_pipe(int *fds, int stream, int close_on_exec)
 371 {
 372         int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
 373
 374         err = socketpair(AF_UNIX, type, 0, fds);
 375         if (err < 0)
 376                 return -errno;
 377
 378         if (!close_on_exec)
 379                 return 0;
 380
 381         err = os_set_exec_close(fds[0]);
 382         if (err < 0)
 383                 goto error;
 384
 385         err = os_set_exec_close(fds[1]);
 386         if (err < 0)
 387                 goto error;
 388
 389         return 0;
 390
 391  error:
 392         printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n",
 393                -err);
 394         close(fds[1]);
 395         close(fds[0]);
 396         return err;
 397 }
 398
 399 int os_set_fd_async(int fd)
 400 {
 401         int err, flags;
 402
 403         flags = fcntl(fd, F_GETFL);
 404         if (flags < 0)
 405                 return -errno;
 406
 407         flags |= O_ASYNC | O_NONBLOCK;
 408         if (fcntl(fd, F_SETFL, flags) < 0) {
 409                 err = -errno;
 410                 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC "
 411                        "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
 412                 return err;
 413         }
 414
 415         if ((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
 416             (fcntl(fd, F_SETOWN, os_getpid()) < 0)) {
 417                 err = -errno;
 418                 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN "
 419                        "(or F_SETSIG) fd %d, errno = %d\n", fd, errno);
 420                 return err;
 421         }
 422
 423         return 0;
 424 }
 425
 426 int os_clear_fd_async(int fd)
 427 {
 428         int flags;
 429
 430         flags = fcntl(fd, F_GETFL);
 431         if (flags < 0)
 432                 return -errno;
 433
 434         flags &= ~(O_ASYNC | O_NONBLOCK);
 435         if (fcntl(fd, F_SETFL, flags) < 0)
 436                 return -errno;
 437         return 0;
 438 }
 439
 440 int os_set_fd_block(int fd, int blocking)
 441 {
 442         int flags;
 443
 444         flags = fcntl(fd, F_GETFL);
 445         if (flags < 0)
 446                 return -errno;
 447
 448         if (blocking)
 449                 flags &= ~O_NONBLOCK;
 450         else
 451                 flags |= O_NONBLOCK;
 452
 453         if (fcntl(fd, F_SETFL, flags) < 0)
 454                 return -errno;
 455
 456         return 0;
 457 }
 458
 459 int os_accept_connection(int fd)
 460 {
 461         int new;
 462
 463         new = accept(fd, NULL, 0);
 464         if (new < 0)
 465                 return -errno;
 466         return new;
 467 }
 468
 469 #ifndef SHUT_RD
 470 #define SHUT_RD 0
 471 #endif
 472
 473 #ifndef SHUT_WR
 474 #define SHUT_WR 1
 475 #endif
 476
 477 #ifndef SHUT_RDWR
 478 #define SHUT_RDWR 2
 479 #endif
 480
 481 int os_shutdown_socket(int fd, int r, int w)
 482 {
 483         int what, err;
 484
 485         if (r && w)
 486                 what = SHUT_RDWR;
 487         else if (r)
 488                 what = SHUT_RD;
 489         else if (w)
 490                 what = SHUT_WR;
 491         else
 492                 return -EINVAL;
 493
 494         err = shutdown(fd, what);
 495         if (err < 0)
 496                 return -errno;
 497         return 0;
 498 }
 499
 500 int os_rcv_fd(int fd, int *helper_pid_out)
 501 {
 502         int new, n;
 503         char buf[CMSG_SPACE(sizeof(new))];
 504         struct msghdr msg;
 505         struct cmsghdr *cmsg;
 506         struct iovec iov;
 507
 508         msg.msg_name = NULL;
 509         msg.msg_namelen = 0;
 510         iov = ((struct iovec) { .iov_base  = helper_pid_out,
 511                                 .iov_len   = sizeof(*helper_pid_out) });
 512         msg.msg_iov = &iov;
 513         msg.msg_iovlen = 1;
 514         msg.msg_control = buf;
 515         msg.msg_controllen = sizeof(buf);
 516         msg.msg_flags = 0;
 517
 518         n = recvmsg(fd, &msg, 0);
 519         if (n < 0)
 520                 return -errno;
 521         else if (n != iov.iov_len)
 522                 *helper_pid_out = -1;
 523
 524         cmsg = CMSG_FIRSTHDR(&msg);
 525         if (cmsg == NULL) {
 526                 printk(UM_KERN_ERR "rcv_fd didn't receive anything, "
 527                        "error = %d\n", errno);
 528                 return -1;
 529         }
 530         if ((cmsg->cmsg_level != SOL_SOCKET) ||
 531             (cmsg->cmsg_type != SCM_RIGHTS)) {
 532                 printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n");
 533                 return -1;
 534         }
 535
 536         new = ((int *) CMSG_DATA(cmsg))[0];
 537         return new;
 538 }
 539
 540 int os_create_unix_socket(const char *file, int len, int close_on_exec)
 541 {
 542         struct sockaddr_un addr;
 543         int sock, err;
 544
 545         sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 546         if (sock < 0)
 547                 return -errno;
 548
 549         if (close_on_exec) {
 550                 err = os_set_exec_close(sock);
 551                 if (err < 0)
 552                         printk(UM_KERN_ERR "create_unix_socket : "
 553                                "close_on_exec failed, err = %d", -err);
 554         }
 555
 556         addr.sun_family = AF_UNIX;
 557
 558         snprintf(addr.sun_path, len, "%s", file);
 559
 560         err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
 561         if (err < 0)
 562                 return -errno;
 563
 564         return sock;
 565 }
 566
 567 void os_flush_stdout(void)
 568 {
 569         fflush(stdout);
 570 }
 571
 572 int os_lock_file(int fd, int excl)
 573 {
 574         int type = excl ? F_WRLCK : F_RDLCK;
 575         struct flock lock = ((struct flock) { .l_type   = type,
 576                                               .l_whence = SEEK_SET,
 577                                               .l_start  = 0,
 578                                               .l_len    = 0 } );
 579         int err, save;
 580
 581         err = fcntl(fd, F_SETLK, &lock);
 582         if (!err)
 583                 goto out;
 584
 585         save = -errno;
 586         err = fcntl(fd, F_GETLK, &lock);
 587         if (err) {
 588                 err = -errno;
 589                 goto out;
 590         }
 591
 592         printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n",
 593                lock.l_pid);
 594         err = save;
 595  out:
 596         return err;
 597 }
 598
 599 unsigned os_major(unsigned long long dev)
 600 {
 601         return major(dev);
 602 }
 603
 604 unsigned os_minor(unsigned long long dev)
 605 {
 606         return minor(dev);
 607 }
 608
 609 unsigned long long os_makedev(unsigned major, unsigned minor)
 610 {
 611         return makedev(major, minor);
 612 }
 613
 614 int os_falloc_punch(int fd, unsigned long long offset, int len)
 615 {
 616         int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len);
 617
 618         if (n < 0)
 619                 return -errno;
 620         return n;
 621 }
 622