示例#1
0
文件: misc.c 项目: Hooman3/minix
/*===========================================================================*
 *				do_fcntl				     *
 *===========================================================================*/
int do_fcntl(void)
{
/* Perform the fcntl(fd, cmd, ...) system call. */

  register struct filp *f;
  int new_fd, fl, r = OK, fcntl_req, fcntl_argx;
  tll_access_t locktype;

  scratch(fp).file.fd_nr = job_m_in.m_lc_vfs_fcntl.fd;
  scratch(fp).io.io_buffer = job_m_in.m_lc_vfs_fcntl.arg_ptr;
  scratch(fp).io.io_nbytes = job_m_in.m_lc_vfs_fcntl.cmd;
  fcntl_req = job_m_in.m_lc_vfs_fcntl.cmd;
  fcntl_argx = job_m_in.m_lc_vfs_fcntl.arg_int;

  /* Is the file descriptor valid? */
  locktype = (fcntl_req == F_FREESP) ? VNODE_WRITE : VNODE_READ;
  if ((f = get_filp(scratch(fp).file.fd_nr, locktype)) == NULL)
	return(err_code);

  switch (fcntl_req) {
    case F_DUPFD:
	/* This replaces the old dup() system call. */
	if (fcntl_argx < 0 || fcntl_argx >= OPEN_MAX) r = EINVAL;
	else if ((r = get_fd(fp, fcntl_argx, 0, &new_fd, NULL)) == OK) {
		f->filp_count++;
		fp->fp_filp[new_fd] = f;
		r = new_fd;
	}
	break;

    case F_GETFD:
	/* Get close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	r = 0;
	if (FD_ISSET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set))
		r = FD_CLOEXEC;
	break;

    case F_SETFD:
	/* Set close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	if (fcntl_argx & FD_CLOEXEC)
		FD_SET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	else
		FD_CLR(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	break;

    case F_GETFL:
	/* Get file status flags (O_NONBLOCK and O_APPEND). */
	fl = f->filp_flags & (O_NONBLOCK | O_APPEND | O_ACCMODE);
	r = fl;
	break;

    case F_SETFL:
	/* Set file status flags (O_NONBLOCK and O_APPEND). */
	fl = O_NONBLOCK | O_APPEND;
	f->filp_flags = (f->filp_flags & ~fl) | (fcntl_argx & fl);
	break;

    case F_GETLK:
    case F_SETLK:
    case F_SETLKW:
	/* Set or clear a file lock. */
	r = lock_op(f, fcntl_req);
	break;

    case F_FREESP:
     {
	/* Free a section of a file */
	off_t start, end, offset;
	struct flock flock_arg;

	/* Check if it's a regular file. */
	if (!S_ISREG(f->filp_vno->v_mode)) r = EINVAL;
	else if (!(f->filp_mode & W_BIT)) r = EBADF;
	else {
		/* Copy flock data from userspace. */
		r = sys_datacopy_wrapper(who_e, scratch(fp).io.io_buffer,
			SELF, (vir_bytes) &flock_arg, sizeof(flock_arg));
	}

	if (r != OK) break;

	/* Convert starting offset to signed. */
	offset = (off_t) flock_arg.l_start;

	/* Figure out starting position base. */
	switch(flock_arg.l_whence) {
	  case SEEK_SET: start = 0; break;
	  case SEEK_CUR: start = f->filp_pos; break;
	  case SEEK_END: start = f->filp_vno->v_size; break;
	  default: r = EINVAL;
	}
	if (r != OK) break;

	/* Check for overflow or underflow. */
	if (offset > 0 && start + offset < start) r = EINVAL;
	else if (offset < 0 && start + offset > start) r = EINVAL;
	else {
		start += offset;
		if (start < 0) r = EINVAL;
	}
	if (r != OK) break;

	if (flock_arg.l_len != 0) {
		if (start >= f->filp_vno->v_size) r = EINVAL;
		else if ((end = start + flock_arg.l_len) <= start) r = EINVAL;
		else if (end > f->filp_vno->v_size) end = f->filp_vno->v_size;
	} else {
                end = 0;
	}
	if (r != OK) break;

	r = req_ftrunc(f->filp_vno->v_fs_e, f->filp_vno->v_inode_nr,start,end);

	if (r == OK && flock_arg.l_len == 0)
		f->filp_vno->v_size = start;

	break;
     }
    case F_GETNOSIGPIPE:
	r = !!(f->filp_flags & O_NOSIGPIPE);
	break;
    case F_SETNOSIGPIPE:
	if (fcntl_argx)
		f->filp_flags |= O_NOSIGPIPE;
	else
		f->filp_flags &= ~O_NOSIGPIPE;
	break;
    case F_FLUSH_FS_CACHE:
    {
	struct vnode *vn = f->filp_vno;
	mode_t mode = f->filp_vno->v_mode;
	if (!super_user) {
		r = EPERM;
	} else if (S_ISBLK(mode)) {
		/* Block device; flush corresponding device blocks. */
		r = req_flush(vn->v_bfs_e, vn->v_sdev);
	} else if (S_ISREG(mode) || S_ISDIR(mode)) {
		/* Directory or regular file; flush hosting FS blocks. */
		r = req_flush(vn->v_fs_e, vn->v_dev);
	} else {
		/* Remaining cases.. Meaning unclear. */
		r = ENODEV;
	}
	break;
    }
    default:
	r = EINVAL;
  }

  unlock_filp(f);
  return(r);
}
示例#2
0
文件: misc.c 项目: mwilbur/minix
/*===========================================================================*
 *				do_fcntl				     *
 *===========================================================================*/
PUBLIC int do_fcntl()
{
/* Perform the fcntl(fd, request, ...) system call. */

  register struct filp *f;
  int new_fd, r, fl;
  struct filp *dummy;

  /* Is the file descriptor valid? */
  if ((f = get_filp(m_in.fd)) == NULL) return(err_code);
  
  switch (m_in.request) {
     case F_DUPFD:
	/* This replaces the old dup() system call. */
	if (m_in.addr < 0 || m_in.addr >= OPEN_MAX) return(EINVAL);
	if ((r = get_fd(m_in.addr, 0, &new_fd, &dummy)) != OK) return(r);
	f->filp_count++;
	fp->fp_filp[new_fd] = f;
	return(new_fd);

     case F_GETFD:
	/* Get close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	return( FD_ISSET(m_in.fd, &fp->fp_cloexec_set) ? FD_CLOEXEC : 0);

     case F_SETFD:
	/* Set close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	if(m_in.addr & FD_CLOEXEC)
		FD_SET(m_in.fd, &fp->fp_cloexec_set);
	else
		FD_CLR(m_in.fd, &fp->fp_cloexec_set);
	return(OK);

     case F_GETFL:
	/* Get file status flags (O_NONBLOCK and O_APPEND). */
	fl = f->filp_flags & (O_NONBLOCK | O_APPEND | O_ACCMODE);
	return(fl);	

     case F_SETFL:
	/* Set file status flags (O_NONBLOCK and O_APPEND). */
	fl = O_NONBLOCK | O_APPEND | O_REOPEN;
	f->filp_flags = (f->filp_flags & ~fl) | (m_in.addr & fl);
	return(OK);

     case F_GETLK:
     case F_SETLK:
     case F_SETLKW:
	/* Set or clear a file lock. */
	r = lock_op(f, m_in.request);
	return(r);

     case F_FREESP:
     {
	/* Free a section of a file. Preparation is done here, actual freeing
	 * in freesp_inode().
	 */
	off_t start, end;
	struct flock flock_arg;
	signed long offset;

	/* Check if it's a regular file. */
	if((f->filp_vno->v_mode & I_TYPE) != I_REGULAR) return(EINVAL);
	if (!(f->filp_mode & W_BIT)) return(EBADF);

	/* Copy flock data from userspace. */
	if((r = sys_datacopy(who_e, (vir_bytes) m_in.name1, SELF, 
	     (vir_bytes) &flock_arg, (phys_bytes) sizeof(flock_arg))) != OK)
		return(r);

	/* Convert starting offset to signed. */
	offset = (signed long) flock_arg.l_start;

	/* Figure out starting position base. */
	switch(flock_arg.l_whence) {
	   case SEEK_SET: start = 0; break;
	   case SEEK_CUR:
	      if (ex64hi(f->filp_pos) != 0) 
			panic("do_fcntl: position in file too high");
	      start = ex64lo(f->filp_pos);
	      break;
	   case SEEK_END: start = f->filp_vno->v_size; break;
	   default: return EINVAL;
	}

	/* Check for overflow or underflow. */
	if(offset > 0 && start + offset < start) return EINVAL;
	if(offset < 0 && start + offset > start) return EINVAL; 
	start += offset;
	if(start < 0) return EINVAL;

	if(flock_arg.l_len != 0) {
		if(start >= f->filp_vno->v_size) return EINVAL;
		end = start + flock_arg.l_len;
		if(end <= start) return EINVAL;
		if(end > f->filp_vno->v_size) end = f->filp_vno->v_size;
	} else {
                end = 0;
	}

	r = req_ftrunc(f->filp_vno->v_fs_e, f->filp_vno->v_inode_nr, start,
		end);

	if(r == OK && flock_arg.l_len == 0)
		f->filp_vno->v_size = start;

	return(r);
     }

     default:
	return(EINVAL);
  }
}
示例#3
0
文件: misc.c 项目: jkiiski/minix
/*===========================================================================*
 *				do_fcntl				     *
 *===========================================================================*/
int do_fcntl()
{
/* Perform the fcntl(fd, request, ...) system call. */

  register struct filp *f;
  int new_fd, fl, r = OK, fcntl_req, fcntl_argx;
  tll_access_t locktype;

  scratch(fp).file.fd_nr = job_m_in.fd;
  scratch(fp).io.io_buffer = job_m_in.buffer;
  scratch(fp).io.io_nbytes = job_m_in.nbytes;	/* a.k.a. m_in.request */
  fcntl_req = job_m_in.request;
  fcntl_argx = job_m_in.addr;

  /* Is the file descriptor valid? */
  locktype = (fcntl_req == F_FREESP) ? VNODE_WRITE : VNODE_READ;
  if ((f = get_filp(scratch(fp).file.fd_nr, locktype)) == NULL)
	return(err_code);

  switch (fcntl_req) {
    case F_DUPFD:
	/* This replaces the old dup() system call. */
	if (fcntl_argx < 0 || fcntl_argx >= OPEN_MAX) r = EINVAL;
	else if ((r = get_fd(fcntl_argx, 0, &new_fd, NULL)) == OK) {
		f->filp_count++;
		fp->fp_filp[new_fd] = f;
		FD_SET(new_fd, &fp->fp_filp_inuse);
		r = new_fd;
	}
	break;

    case F_GETFD:
	/* Get close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	r = 0;
	if (FD_ISSET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set))
		r = FD_CLOEXEC;
	break;

    case F_SETFD:
	/* Set close-on-exec flag (FD_CLOEXEC in POSIX Table 6-2). */
	if (fcntl_argx & FD_CLOEXEC)
		FD_SET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	else
		FD_CLR(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
	break;

    case F_GETFL:
	/* Get file status flags (O_NONBLOCK and O_APPEND). */
	fl = f->filp_flags & (O_NONBLOCK | O_APPEND | O_ACCMODE);
	r = fl;
	break;

    case F_SETFL:
	/* Set file status flags (O_NONBLOCK and O_APPEND). */
	fl = O_NONBLOCK | O_APPEND | O_REOPEN;
	f->filp_flags = (f->filp_flags & ~fl) | (fcntl_argx & fl);
	break;

    case F_GETLK:
    case F_SETLK:
    case F_SETLKW:
	/* Set or clear a file lock. */
	r = lock_op(f, fcntl_req);
	break;

    case F_FREESP:
     {
	/* Free a section of a file */
	off_t start, end;
	struct flock flock_arg;
	signed long offset;

	/* Check if it's a regular file. */
	if (!S_ISREG(f->filp_vno->v_mode)) r = EINVAL;
	else if (!(f->filp_mode & W_BIT)) r = EBADF;
	else
		/* Copy flock data from userspace. */
		r = sys_datacopy(who_e, (vir_bytes) scratch(fp).io.io_buffer,
				 SELF, (vir_bytes) &flock_arg,
				 sizeof(flock_arg));

	if (r != OK) break;

	/* Convert starting offset to signed. */
	offset = (signed long) flock_arg.l_start;

	/* Figure out starting position base. */
	switch(flock_arg.l_whence) {
	  case SEEK_SET: start = 0; break;
	  case SEEK_CUR:
		if (ex64hi(f->filp_pos) != 0)
			panic("do_fcntl: position in file too high");
		start = ex64lo(f->filp_pos);
		break;
	  case SEEK_END: start = f->filp_vno->v_size; break;
	  default: r = EINVAL;
	}
	if (r != OK) break;

	/* Check for overflow or underflow. */
	if (offset > 0 && start + offset < start) r = EINVAL;
	else if (offset < 0 && start + offset > start) r = EINVAL;
	else {
		start += offset;
		if (start < 0) r = EINVAL;
	}
	if (r != OK) break;

	if (flock_arg.l_len != 0) {
		if (start >= f->filp_vno->v_size) r = EINVAL;
		else if ((end = start + flock_arg.l_len) <= start) r = EINVAL;
		else if (end > f->filp_vno->v_size) end = f->filp_vno->v_size;
	} else {
                end = 0;
	}
	if (r != OK) break;

	r = req_ftrunc(f->filp_vno->v_fs_e, f->filp_vno->v_inode_nr,start,end);

	if (r == OK && flock_arg.l_len == 0)
		f->filp_vno->v_size = start;

	break;
     }
    case F_GETNOSIGPIPE:
	/* POSIX: return value other than -1 is flag is set, else -1 */
	r = -1;
	if (f->filp_flags & O_NOSIGPIPE)
		r = 0;
	break;
    case F_SETNOSIGPIPE:
	fl = (O_NOSIGPIPE);
	f->filp_flags = (f->filp_flags & ~fl) | (fcntl_argx & fl);
	break;
    default:
	r = EINVAL;
  }

  unlock_filp(f);
  return(r);
}