arch/um/os-Linux/file.c

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