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 void os_print_error(int error, const char* str)
  86 {
  87         errno = error < 0 ? -error : error;
  88
  89         perror(str);
  90 }
  91
  92 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
  93 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
  94 {
  95         int err;
  96
  97         err = ioctl(fd, cmd, arg);
  98         if(err < 0)
  99                 return -errno;
 100
 101         return err;
 102 }
 103
 104 int os_window_size(int fd, int *rows, int *cols)
 105 {
 106         struct winsize size;
 107
 108         if(ioctl(fd, TIOCGWINSZ, &size) < 0)
 109                 return -errno;
 110
 111         *rows = size.ws_row;
 112         *cols = size.ws_col;
 113
 114         return 0;
 115 }
 116
 117 int os_new_tty_pgrp(int fd, int pid)
 118 {
 119         if(ioctl(fd, TIOCSCTTY, 0) < 0)
 120                 return -errno;
 121
 122         if(tcsetpgrp(fd, pid) < 0)
 123                 return -errno;
 124
 125         return 0;
 126 }
 127
 128 /* FIXME: ensure namebuf in os_get_if_name is big enough */
 129 int os_get_ifname(int fd, char* namebuf)
 130 {
 131         if(ioctl(fd, SIOCGIFNAME, namebuf) < 0)
 132                 return -errno;
 133
 134         return 0;
 135 }
 136
 137 int os_set_slip(int fd)
 138 {
 139         int disc, sencap;
 140
 141         disc = N_SLIP;
 142         if(ioctl(fd, TIOCSETD, &disc) < 0)
 143                 return -errno;
 144
 145         sencap = 0;
 146         if(ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
 147                 return -errno;
 148
 149         return 0;
 150 }
 151
 152 int os_set_owner(int fd, int pid)
 153 {
 154         if(fcntl(fd, F_SETOWN, pid) < 0){
 155                 int save_errno = errno;
 156
 157                 if(fcntl(fd, F_GETOWN, 0) != pid)
 158                         return -save_errno;
 159         }
 160
 161         return 0;
 162 }
 163
 164 int os_mode_fd(int fd, int mode)
 165 {
 166         int err;
 167
 168         do {
 169                 err = fchmod(fd, mode);
 170         } while((err < 0) && (errno==EINTR)) ;
 171
 172         if(err < 0)
 173                 return -errno;
 174
 175         return 0;
 176 }
 177
 178 int os_file_type(char *file)
 179 {
 180         struct uml_stat buf;
 181         int err;
 182
 183         err = os_stat_file(file, &buf);
 184         if(err < 0)
 185                 return err;
 186
 187         if(S_ISDIR(buf.ust_mode))
 188                 return OS_TYPE_DIR;
 189         else if(S_ISLNK(buf.ust_mode))
 190                 return OS_TYPE_SYMLINK;
 191         else if(S_ISCHR(buf.ust_mode))
 192                 return OS_TYPE_CHARDEV;
 193         else if(S_ISBLK(buf.ust_mode))
 194                 return OS_TYPE_BLOCKDEV;
 195         else if(S_ISFIFO(buf.ust_mode))
 196                 return OS_TYPE_FIFO;
 197         else if(S_ISSOCK(buf.ust_mode))
 198                 return OS_TYPE_SOCK;
 199         else return OS_TYPE_FILE;
 200 }
 201
 202 int os_file_mode(char *file, struct openflags *mode_out)
 203 {
 204         int err;
 205
 206         *mode_out = OPENFLAGS();
 207
 208         err = os_access(file, OS_ACC_W_OK);
 209         if((err < 0) && (err != -EACCES))
 210                 return(err);
 211
 212         *mode_out = of_write(*mode_out);
 213
 214         err = os_access(file, OS_ACC_R_OK);
 215         if((err < 0) && (err != -EACCES))
 216                 return(err);
 217
 218         *mode_out = of_read(*mode_out);
 219
 220         return(0);
 221 }
 222
 223 int os_open_file(char *file, struct openflags flags, int mode)
 224 {
 225         int fd, err, f = 0;
 226
 227         if(flags.r && flags.w) f = O_RDWR;
 228         else if(flags.r) f = O_RDONLY;
 229         else if(flags.w) f = O_WRONLY;
 230         else f = 0;
 231
 232         if(flags.s) f |= O_SYNC;
 233         if(flags.c) f |= O_CREAT;
 234         if(flags.t) f |= O_TRUNC;
 235         if(flags.e) f |= O_EXCL;
 236
 237         fd = open64(file, f, mode);
 238         if(fd < 0)
 239                 return(-errno);
 240
 241         if(flags.cl && fcntl(fd, F_SETFD, 1)){
 242                 err = -errno;
 243                 os_close_file(fd);
 244                 return err;
 245         }
 246
 247         return(fd);
 248 }
 249
 250 int os_connect_socket(char *name)
 251 {
 252         struct sockaddr_un sock;
 253         int fd, err;
 254
 255         sock.sun_family = AF_UNIX;
 256         snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
 257
 258         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 259         if(fd < 0) {
 260                 err = -errno;
 261                 goto out;
 262         }
 263
 264         err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
 265         if(err) {
 266                 err = -errno;
 267                 goto out_close;
 268         }
 269
 270         return fd;
 271
 272 out_close:
 273         close(fd);
 274 out:
 275         return err;
 276 }
 277
 278 void os_close_file(int fd)
 279 {
 280         close(fd);
 281 }
 282
 283 int os_seek_file(int fd, __u64 offset)
 284 {
 285         __u64 actual;
 286
 287         actual = lseek64(fd, offset, SEEK_SET);
 288         if(actual != offset)
 289                 return -errno;
 290         return 0;
 291 }
 292
 293 static int fault_buffer(void *start, int len,
 294                         int (*copy_proc)(void *addr, void *buf, int len))
 295 {
 296         int page = getpagesize(), i;
 297         char c;
 298
 299         for(i = 0; i < len; i += page){
 300                 if((*copy_proc)(start + i, &c, sizeof(c)))
 301                         return -EFAULT;
 302         }
 303         if((len % page) != 0){
 304                 if((*copy_proc)(start + len - 1, &c, sizeof(c)))
 305                         return -EFAULT;
 306         }
 307         return 0;
 308 }
 309
 310 static int file_io(int fd, void *buf, int len,
 311                    int (*io_proc)(int fd, void *buf, int len),
 312                    int (*copy_user_proc)(void *addr, void *buf, int len))
 313 {
 314         int n, err;
 315
 316         do {
 317                 n = (*io_proc)(fd, buf, len);
 318                 if((n < 0) && (errno == EFAULT)){
 319                         err = fault_buffer(buf, len, copy_user_proc);
 320                         if(err)
 321                                 return err;
 322                         n = (*io_proc)(fd, buf, len);
 323                 }
 324         } while((n < 0) && (errno == EINTR));
 325
 326         if(n < 0)
 327                 return -errno;
 328         return n;
 329 }
 330
 331 int os_read_file(int fd, void *buf, int len)
 332 {
 333         return file_io(fd, buf, len, (int (*)(int, void *, int)) read,
 334                        copy_from_user_proc);
 335 }
 336
 337 int os_read_file_k(int fd, void *buf, int len)
 338 {
 339         int n = read(fd, buf, len);
 340
 341         if(n < 0)
 342                 return -errno;
 343         return n;
 344 }
 345
 346 int os_write_file(int fd, const void *buf, int len)
 347 {
 348         return file_io(fd, (void *) buf, len,
 349                        (int (*)(int, void *, int)) write, copy_to_user_proc);
 350 }
 351
 352 int os_write_file_k(int fd, const void *buf, int len)
 353 {
 354         int n = write(fd, (void *) buf, len);
 355
 356         if(n < 0)
 357                 return -errno;
 358         return n;
 359 }
 360
 361 int os_file_size(char *file, unsigned long long *size_out)
 362 {
 363         struct uml_stat buf;
 364         int err;
 365
 366         err = os_stat_file(file, &buf);
 367         if(err < 0){
 368                 printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
 369                 return(err);
 370         }
 371
 372         if(S_ISBLK(buf.ust_mode)){
 373                 int fd, blocks;
 374
 375                 fd = os_open_file(file, of_read(OPENFLAGS()), 0);
 376                 if(fd < 0){
 377                         printk("Couldn't open \"%s\", errno = %d\n", file, -fd);
 378                         return(fd);
 379                 }
 380                 if(ioctl(fd, BLKGETSIZE, &blocks) < 0){
 381                         err = -errno;
 382                         printk("Couldn't get the block size of \"%s\", "
 383                                "errno = %d\n", file, errno);
 384                         os_close_file(fd);
 385                         return(err);
 386                 }
 387                 *size_out = ((long long) blocks) * 512;
 388                 os_close_file(fd);
 389                 return(0);
 390         }
 391         *size_out = buf.ust_size;
 392         return(0);
 393 }
 394
 395 int os_file_modtime(char *file, unsigned long *modtime)
 396 {
 397         struct uml_stat buf;
 398         int err;
 399
 400         err = os_stat_file(file, &buf);
 401         if(err < 0){
 402                 printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
 403                 return err;
 404         }
 405
 406         *modtime = buf.ust_mtime;
 407         return 0;
 408 }
 409
 410 int os_get_exec_close(int fd, int* close_on_exec)
 411 {
 412         int ret;
 413
 414         do {
 415                 ret = fcntl(fd, F_GETFD);
 416         } while((ret < 0) && (errno == EINTR)) ;
 417
 418         if(ret < 0)
 419                 return(-errno);
 420
 421         *close_on_exec = (ret&FD_CLOEXEC) ? 1 : 0;
 422         return(ret);
 423 }
 424
 425 int os_set_exec_close(int fd, int close_on_exec)
 426 {
 427         int flag, err;
 428
 429         if(close_on_exec) flag = FD_CLOEXEC;
 430         else flag = 0;
 431
 432         do {
 433                 err = fcntl(fd, F_SETFD, flag);
 434         } while((err < 0) && (errno == EINTR)) ;
 435
 436         if(err < 0)
 437                 return(-errno);
 438         return(err);
 439 }
 440
 441 int os_pipe(int *fds, int stream, int close_on_exec)
 442 {
 443         int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
 444
 445         err = socketpair(AF_UNIX, type, 0, fds);
 446         if(err < 0)
 447                 return(-errno);
 448
 449         if(!close_on_exec)
 450                 return(0);
 451
 452         err = os_set_exec_close(fds[0], 1);
 453         if(err < 0)
 454                 goto error;
 455
 456         err = os_set_exec_close(fds[1], 1);
 457         if(err < 0)
 458                 goto error;
 459
 460         return 0;
 461
 462  error:
 463         printk("os_pipe : Setting FD_CLOEXEC failed, err = %d\n", -err);
 464         os_close_file(fds[1]);
 465         os_close_file(fds[0]);
 466         return(err);
 467 }
 468
 469 int os_set_fd_async(int fd, int owner)
 470 {
 471         int err;
 472
 473         /* XXX This should do F_GETFL first */
 474         if(fcntl(fd, F_SETFL, O_ASYNC | O_NONBLOCK) < 0){
 475                 err = -errno;
 476                 printk("os_set_fd_async : failed to set O_ASYNC and "
 477                        "O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
 478                 return err;
 479         }
 480 #ifdef notdef
 481         if(fcntl(fd, F_SETFD, 1) < 0){
 482                 printk("os_set_fd_async : Setting FD_CLOEXEC failed, "
 483                        "errno = %d\n", errno);
 484         }
 485 #endif
 486
 487         if((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
 488            (fcntl(fd, F_SETOWN, owner) < 0)){
 489                 err = -errno;
 490                 printk("os_set_fd_async : Failed to fcntl F_SETOWN "
 491                        "(or F_SETSIG) fd %d to pid %d, errno = %d\n", fd,
 492                        owner, errno);
 493                 return err;
 494         }
 495
 496         return 0;
 497 }
 498
 499 int os_clear_fd_async(int fd)
 500 {
 501         int flags = fcntl(fd, F_GETFL);
 502
 503         flags &= ~(O_ASYNC | O_NONBLOCK);
 504         if(fcntl(fd, F_SETFL, flags) < 0)
 505                 return -errno;
 506         return 0;
 507 }
 508
 509 int os_set_fd_block(int fd, int blocking)
 510 {
 511         int flags;
 512
 513         flags = fcntl(fd, F_GETFL);
 514
 515         if(blocking) flags &= ~O_NONBLOCK;
 516         else flags |= O_NONBLOCK;
 517
 518         if(fcntl(fd, F_SETFL, flags) < 0)
 519                 return -errno;
 520
 521         return 0;
 522 }
 523
 524 int os_accept_connection(int fd)
 525 {
 526         int new;
 527
 528         new = accept(fd, NULL, 0);
 529         if(new < 0)
 530                 return -errno;
 531         return new;
 532 }
 533
 534 #ifndef SHUT_RD
 535 #define SHUT_RD 0
 536 #endif
 537
 538 #ifndef SHUT_WR
 539 #define SHUT_WR 1
 540 #endif
 541
 542 #ifndef SHUT_RDWR
 543 #define SHUT_RDWR 2
 544 #endif
 545
 546 int os_shutdown_socket(int fd, int r, int w)
 547 {
 548         int what, err;
 549
 550         if(r && w) what = SHUT_RDWR;
 551         else if(r) what = SHUT_RD;
 552         else if(w) what = SHUT_WR;
 553         else {
 554                 printk("os_shutdown_socket : neither r or w was set\n");
 555                 return -EINVAL;
 556         }
 557         err = shutdown(fd, what);
 558         if(err < 0)
 559                 return -errno;
 560         return 0;
 561 }
 562
 563 int os_rcv_fd(int fd, int *helper_pid_out)
 564 {
 565         int new, n;
 566         char buf[CMSG_SPACE(sizeof(new))];
 567         struct msghdr msg;
 568         struct cmsghdr *cmsg;
 569         struct iovec iov;
 570
 571         msg.msg_name = NULL;
 572         msg.msg_namelen = 0;
 573         iov = ((struct iovec) { .iov_base  = helper_pid_out,
 574                                 .iov_len   = sizeof(*helper_pid_out) });
 575         msg.msg_iov = &iov;
 576         msg.msg_iovlen = 1;
 577         msg.msg_control = buf;
 578         msg.msg_controllen = sizeof(buf);
 579         msg.msg_flags = 0;
 580
 581         n = recvmsg(fd, &msg, 0);
 582         if(n < 0)
 583                 return -errno;
 584
 585         else if(n != sizeof(iov.iov_len))
 586                 *helper_pid_out = -1;
 587
 588         cmsg = CMSG_FIRSTHDR(&msg);
 589         if(cmsg == NULL){
 590                 printk("rcv_fd didn't receive anything, error = %d\n", errno);
 591                 return -1;
 592         }
 593         if((cmsg->cmsg_level != SOL_SOCKET) ||
 594            (cmsg->cmsg_type != SCM_RIGHTS)){
 595                 printk("rcv_fd didn't receive a descriptor\n");
 596                 return -1;
 597         }
 598
 599         new = ((int *) CMSG_DATA(cmsg))[0];
 600         return new;
 601 }
 602
 603 int os_create_unix_socket(char *file, int len, int close_on_exec)
 604 {
 605         struct sockaddr_un addr;
 606         int sock, err;
 607
 608         sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 609         if(sock < 0)
 610                 return -errno;
 611
 612         if(close_on_exec) {
 613                 err = os_set_exec_close(sock, 1);
 614                 if(err < 0)
 615                         printk("create_unix_socket : close_on_exec failed, "
 616                        "err = %d", -err);
 617         }
 618
 619         addr.sun_family = AF_UNIX;
 620
 621         /* XXX Be more careful about overflow */
 622         snprintf(addr.sun_path, len, "%s", file);
 623
 624         err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
 625         if(err < 0)
 626                 return -errno;
 627
 628         return sock;
 629 }
 630
 631 void os_flush_stdout(void)
 632 {
 633         fflush(stdout);
 634 }
 635
 636 int os_lock_file(int fd, int excl)
 637 {
 638         int type = excl ? F_WRLCK : F_RDLCK;
 639         struct flock lock = ((struct flock) { .l_type   = type,
 640                                               .l_whence = SEEK_SET,
 641                                               .l_start  = 0,
 642                                               .l_len    = 0 } );
 643         int err, save;
 644
 645         err = fcntl(fd, F_SETLK, &lock);
 646         if(!err)
 647                 goto out;
 648
 649         save = -errno;
 650         err = fcntl(fd, F_GETLK, &lock);
 651         if(err){
 652                 err = -errno;
 653                 goto out;
 654         }
 655
 656         printk("F_SETLK failed, file already locked by pid %d\n", lock.l_pid);
 657         err = save;
 658  out:
 659         return err;
 660 }