Logo Search packages:      
Sourcecode: linux version File versions  Download package

file.c

/*
 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/uio.h>
#include "os.h"
#include "user.h"
#include "kern_util.h"

static void copy_stat(struct uml_stat *dst, struct stat64 *src)
{
      *dst = ((struct uml_stat) {
            .ust_dev     = src->st_dev,     /* device */
            .ust_ino     = src->st_ino,     /* inode */
            .ust_mode    = src->st_mode,    /* protection */
            .ust_nlink   = src->st_nlink,   /* number of hard links */
            .ust_uid     = src->st_uid,     /* user ID of owner */
            .ust_gid     = src->st_gid,     /* group ID of owner */
            .ust_size    = src->st_size,    /* total size, in bytes */
            .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
            .ust_blocks  = src->st_blocks,  /* number of blocks allocated */
            .ust_atime   = src->st_atime,   /* time of last access */
            .ust_mtime   = src->st_mtime,   /* time of last modification */
            .ust_ctime   = src->st_ctime,   /* time of last change */
      });
}

int os_stat_fd(const int fd, struct uml_stat *ubuf)
{
      struct stat64 sbuf;
      int err;

      CATCH_EINTR(err = fstat64(fd, &sbuf));
      if(err < 0)
            return -errno;

      if(ubuf != NULL)
            copy_stat(ubuf, &sbuf);
      return err;
}

int os_stat_file(const char *file_name, struct uml_stat *ubuf)
{
      struct stat64 sbuf;
      int err;

      do {
            err = stat64(file_name, &sbuf);
      } while((err < 0) && (errno == EINTR)) ;

      if(err < 0)
            return -errno;

      if(ubuf != NULL)
            copy_stat(ubuf, &sbuf);
      return err;
}

int os_access(const char* file, int mode)
{
      int amode, err;

      amode=(mode&OS_ACC_R_OK ? R_OK : 0) | (mode&OS_ACC_W_OK ? W_OK : 0) |
            (mode&OS_ACC_X_OK ? X_OK : 0) | (mode&OS_ACC_F_OK ? F_OK : 0) ;

      err = access(file, amode);
      if(err < 0)
            return -errno;

      return 0;
}

/* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
{
      int err;

      err = ioctl(fd, cmd, arg);
      if(err < 0)
            return -errno;

      return err;
}

/* FIXME: ensure namebuf in os_get_if_name is big enough */
int os_get_ifname(int fd, char* namebuf)
{
      if(ioctl(fd, SIOCGIFNAME, namebuf) < 0)
            return -errno;

      return 0;
}

int os_set_slip(int fd)
{
      int disc, sencap;

      disc = N_SLIP;
      if(ioctl(fd, TIOCSETD, &disc) < 0)
            return -errno;

      sencap = 0;
      if(ioctl(fd, SIOCSIFENCAP, &sencap) < 0)
            return -errno;

      return 0;
}

int os_set_owner(int fd, int pid)
{
      if(fcntl(fd, F_SETOWN, pid) < 0){
            int save_errno = errno;

            if(fcntl(fd, F_GETOWN, 0) != pid)
                  return -save_errno;
      }

      return 0;
}

int os_mode_fd(int fd, int mode)
{
      int err;

      do {
            err = fchmod(fd, mode);
      } while((err < 0) && (errno==EINTR)) ;

      if(err < 0)
            return -errno;

      return 0;
}

int os_file_type(char *file)
{
      struct uml_stat buf;
      int err;

      err = os_stat_file(file, &buf);
      if(err < 0)
            return err;

      if(S_ISDIR(buf.ust_mode))
            return OS_TYPE_DIR;
      else if(S_ISLNK(buf.ust_mode))
            return OS_TYPE_SYMLINK;
      else if(S_ISCHR(buf.ust_mode))
            return OS_TYPE_CHARDEV;
      else if(S_ISBLK(buf.ust_mode))
            return OS_TYPE_BLOCKDEV;
      else if(S_ISFIFO(buf.ust_mode))
            return OS_TYPE_FIFO;
      else if(S_ISSOCK(buf.ust_mode))
            return OS_TYPE_SOCK;
      else return OS_TYPE_FILE;
}

int os_file_mode(char *file, struct openflags *mode_out)
{
      int err;

      *mode_out = OPENFLAGS();

      err = access(file, W_OK);
      if(err && (errno != EACCES))
            return -errno;
      else if(!err)
            *mode_out = of_write(*mode_out);

      err = access(file, R_OK);
      if(err && (errno != EACCES))
            return -errno;
      else if(!err)
            *mode_out = of_read(*mode_out);

      return err;
}

int os_open_file(char *file, struct openflags flags, int mode)
{
      int fd, err, f = 0;

      if(flags.r && flags.w) f = O_RDWR;
      else if(flags.r) f = O_RDONLY;
      else if(flags.w) f = O_WRONLY;
      else f = 0;

      if(flags.s) f |= O_SYNC;
      if(flags.c) f |= O_CREAT;
      if(flags.t) f |= O_TRUNC;
      if(flags.e) f |= O_EXCL;

      fd = open64(file, f, mode);
      if(fd < 0)
            return -errno;

      if(flags.cl && fcntl(fd, F_SETFD, 1)){
            err = -errno;
            close(fd);
            return err;
      }

      return fd;
}

int os_connect_socket(char *name)
{
      struct sockaddr_un sock;
      int fd, err;

      sock.sun_family = AF_UNIX;
      snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);

      fd = socket(AF_UNIX, SOCK_STREAM, 0);
      if(fd < 0) {
            err = -errno;
            goto out;
      }

      err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
      if(err) {
            err = -errno;
            goto out_close;
      }

      return fd;

out_close:
      close(fd);
out:
      return err;
}

void os_close_file(int fd)
{
      close(fd);
}

int os_seek_file(int fd, unsigned long long offset)
{
      unsigned long long actual;

      actual = lseek64(fd, offset, SEEK_SET);
      if(actual != offset)
            return -errno;
      return 0;
}

int os_read_file(int fd, void *buf, int len)
{
      int n = read(fd, buf, len);

      if(n < 0)
            return -errno;
      return n;
}

int os_write_file(int fd, const void *buf, int len)
{
      int n = write(fd, (void *) buf, len);

      if(n < 0)
            return -errno;
      return n;
}

int os_file_size(char *file, unsigned long long *size_out)
{
      struct uml_stat buf;
      int err;

      err = os_stat_file(file, &buf);
      if(err < 0){
            printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
            return err;
      }

      if(S_ISBLK(buf.ust_mode)){
            int fd;
            long blocks;

            fd = open(file, O_RDONLY, 0);
            if(fd < 0) {
                  err = -errno;
                  printk("Couldn't open \"%s\", errno = %d\n", file,
                         errno);
                  return err;
            }
            if(ioctl(fd, BLKGETSIZE, &blocks) < 0){
                  err = -errno;
                  printk("Couldn't get the block size of \"%s\", "
                         "errno = %d\n", file, errno);
                  close(fd);
                  return err;
            }
            *size_out = ((long long) blocks) * 512;
            close(fd);
      }
      else *size_out = buf.ust_size;

      return 0;
}

int os_file_modtime(char *file, unsigned long *modtime)
{
      struct uml_stat buf;
      int err;

      err = os_stat_file(file, &buf);
      if(err < 0){
            printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
            return err;
      }

      *modtime = buf.ust_mtime;
      return 0;
}

int os_get_exec_close(int fd, int *close_on_exec)
{
      int ret;

      CATCH_EINTR(ret = fcntl(fd, F_GETFD));

      if(ret < 0)
            return -errno;

      *close_on_exec = (ret & FD_CLOEXEC) ? 1 : 0;
      return ret;
}

int os_set_exec_close(int fd)
{
      int err;

      CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC));

      if(err < 0)
            return -errno;
      return err;
}

int os_pipe(int *fds, int stream, int close_on_exec)
{
      int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;

      err = socketpair(AF_UNIX, type, 0, fds);
      if(err < 0)
            return -errno;

      if(!close_on_exec)
            return 0;

      err = os_set_exec_close(fds[0]);
      if(err < 0)
            goto error;

      err = os_set_exec_close(fds[1]);
      if(err < 0)
            goto error;

      return 0;

 error:
      printk("os_pipe : Setting FD_CLOEXEC failed, err = %d\n", -err);
      close(fds[1]);
      close(fds[0]);
      return err;
}

int os_set_fd_async(int fd, int owner)
{
      int err;

      /* XXX This should do F_GETFL first */
      if(fcntl(fd, F_SETFL, O_ASYNC | O_NONBLOCK) < 0){
            err = -errno;
            printk("os_set_fd_async : failed to set O_ASYNC and "
                   "O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
            return err;
      }
#ifdef notdef
      if(fcntl(fd, F_SETFD, 1) < 0){
            printk("os_set_fd_async : Setting FD_CLOEXEC failed, "
                   "errno = %d\n", errno);
      }
#endif

      if((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
         (fcntl(fd, F_SETOWN, owner) < 0)){
            err = -errno;
            printk("os_set_fd_async : Failed to fcntl F_SETOWN "
                   "(or F_SETSIG) fd %d to pid %d, errno = %d\n", fd,
                   owner, errno);
            return err;
      }

      return 0;
}

int os_clear_fd_async(int fd)
{
      int flags = fcntl(fd, F_GETFL);

      flags &= ~(O_ASYNC | O_NONBLOCK);
      if(fcntl(fd, F_SETFL, flags) < 0)
            return -errno;
      return 0;
}

int os_set_fd_block(int fd, int blocking)
{
      int flags;

      flags = fcntl(fd, F_GETFL);

      if(blocking) flags &= ~O_NONBLOCK;
      else flags |= O_NONBLOCK;

      if(fcntl(fd, F_SETFL, flags) < 0)
            return -errno;

      return 0;
}

int os_accept_connection(int fd)
{
      int new;

      new = accept(fd, NULL, 0);
      if(new < 0)
            return -errno;
      return new;
}

#ifndef SHUT_RD
#define SHUT_RD 0
#endif

#ifndef SHUT_WR
#define SHUT_WR 1
#endif

#ifndef SHUT_RDWR
#define SHUT_RDWR 2
#endif

int os_shutdown_socket(int fd, int r, int w)
{
      int what, err;

      if(r && w) what = SHUT_RDWR;
      else if(r) what = SHUT_RD;
      else if(w) what = SHUT_WR;
      else {
            printk("os_shutdown_socket : neither r or w was set\n");
            return -EINVAL;
      }
      err = shutdown(fd, what);
      if(err < 0)
            return -errno;
      return 0;
}

int os_rcv_fd(int fd, int *helper_pid_out)
{
      int new, n;
      char buf[CMSG_SPACE(sizeof(new))];
      struct msghdr msg;
      struct cmsghdr *cmsg;
      struct iovec iov;

      msg.msg_name = NULL;
      msg.msg_namelen = 0;
      iov = ((struct iovec) { .iov_base  = helper_pid_out,
                        .iov_len   = sizeof(*helper_pid_out) });
      msg.msg_iov = &iov;
      msg.msg_iovlen = 1;
      msg.msg_control = buf;
      msg.msg_controllen = sizeof(buf);
      msg.msg_flags = 0;

      n = recvmsg(fd, &msg, 0);
      if(n < 0)
            return -errno;
      else if(n != iov.iov_len)
            *helper_pid_out = -1;

      cmsg = CMSG_FIRSTHDR(&msg);
      if(cmsg == NULL){
            printk("rcv_fd didn't receive anything, error = %d\n", errno);
            return -1;
      }
      if((cmsg->cmsg_level != SOL_SOCKET) ||
         (cmsg->cmsg_type != SCM_RIGHTS)){
            printk("rcv_fd didn't receive a descriptor\n");
            return -1;
      }

      new = ((int *) CMSG_DATA(cmsg))[0];
      return new;
}

int os_create_unix_socket(char *file, int len, int close_on_exec)
{
      struct sockaddr_un addr;
      int sock, err;

      sock = socket(PF_UNIX, SOCK_DGRAM, 0);
      if(sock < 0)
            return -errno;

      if(close_on_exec) {
            err = os_set_exec_close(sock);
            if(err < 0)
                  printk("create_unix_socket : close_on_exec failed, "
                   "err = %d", -err);
      }

      addr.sun_family = AF_UNIX;

      /* XXX Be more careful about overflow */
      snprintf(addr.sun_path, len, "%s", file);

      err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
      if(err < 0)
            return -errno;

      return sock;
}

void os_flush_stdout(void)
{
      fflush(stdout);
}

int os_lock_file(int fd, int excl)
{
      int type = excl ? F_WRLCK : F_RDLCK;
      struct flock lock = ((struct flock) { .l_type   = type,
                                    .l_whence   = SEEK_SET,
                                    .l_start    = 0,
                                    .l_len      = 0 } );
      int err, save;

      err = fcntl(fd, F_SETLK, &lock);
      if(!err)
            goto out;

      save = -errno;
      err = fcntl(fd, F_GETLK, &lock);
      if(err){
            err = -errno;
            goto out;
      }

      printk("F_SETLK failed, file already locked by pid %d\n", lock.l_pid);
      err = save;
 out:
      return err;
}

Generated by  Doxygen 1.6.0   Back to index