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