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