コード例 #1
0
ファイル: TerrainIO.cpp プロジェクト: 136048599/vrbrain
/*
  write out disk_block
 */
void AP_Terrain::write_block(void)
{
    seek_offset();
    if (io_failure) {
        return;
    }

    disk_block.block.crc = get_block_crc(disk_block.block);

    ssize_t ret = ::write(fd, &disk_block, sizeof(disk_block));
    if (ret  != sizeof(disk_block)) {
#if TERRAIN_DEBUG
        hal.console->printf("write failed - %s\n", strerror(errno));
#endif
        ::close(fd);
        fd = -1;
        io_failure = true;
    } else {
        ::fsync(fd);
#if TERRAIN_DEBUG
        printf("wrote block at %ld %ld ret=%d mask=%07llx\n",
               (long)disk_block.block.lat,
               (long)disk_block.block.lon,
               (int)ret,
               (unsigned long long)disk_block.block.bitmap);
#endif
    }
    disk_io_state = DiskIoDoneWrite;
}
コード例 #2
0
ファイル: TerrainIO.cpp プロジェクト: 136048599/vrbrain
/*
  read in disk_block
 */
void AP_Terrain::read_block(void)
{
    seek_offset();
    if (io_failure) {
        return;
    }
    int32_t lat = disk_block.block.lat;
    int32_t lon = disk_block.block.lon;

    ssize_t ret = ::read(fd, &disk_block, sizeof(disk_block));
    if (ret != sizeof(disk_block) || 
        disk_block.block.lat != lat || 
        disk_block.block.lon != lon ||
        disk_block.block.bitmap == 0 ||
        disk_block.block.spacing != grid_spacing ||
        disk_block.block.version != TERRAIN_GRID_FORMAT_VERSION ||
        disk_block.block.crc != get_block_crc(disk_block.block)) {
#if TERRAIN_DEBUG
        printf("read empty block at %ld %ld ret=%d\n",
               (long)lat,
               (long)lon,
               (int)ret);
#endif
        // a short read or bad data is not an IO failure, just a
        // missing block on disk
        memset(&disk_block, 0, sizeof(disk_block));
        disk_block.block.lat = lat;
        disk_block.block.lon = lon;
        disk_block.block.bitmap = 0;
    } else {
#if TERRAIN_DEBUG
        printf("read block at %ld %ld ret=%d mask=%07llx\n",
               (long)lat,
               (long)lon,
               (int)ret,
               (unsigned long long)disk_block.block.bitmap);
#endif
    }
    disk_io_state = DiskIoDoneRead;
}
コード例 #3
0
ファイル: position.c プロジェクト: 2asoft/freebsd
/*
 * Position input/output data streams before starting the copy.  Device type
 * dependent.  Seekable devices use lseek, and the rest position by reading.
 * Seeking past the end of file can cause null blocks to be written to the
 * output.
 */
void
pos_in(void)
{
	off_t cnt;
	int warned;
	ssize_t nr;
	size_t bcnt;

	/* If known to be seekable, try to seek on it. */
	if (in.flags & ISSEEK) {
		errno = 0;
		if (lseek(in.fd, seek_offset(&in), SEEK_CUR) == -1 &&
		    errno != 0)
			err(1, "%s", in.name);
		return;
	}

	/* Don't try to read a really weird amount (like negative). */
	if (in.offset < 0)
		errx(1, "%s: illegal offset", "iseek/skip");

	/*
	 * Read the data.  If a pipe, read until satisfy the number of bytes
	 * being skipped.  No differentiation for reading complete and partial
	 * blocks for other devices.
	 */
	for (bcnt = in.dbsz, cnt = in.offset, warned = 0; cnt;) {
		if ((nr = read(in.fd, in.db, bcnt)) > 0) {
			if (in.flags & ISPIPE) {
				if (!(bcnt -= nr)) {
					bcnt = in.dbsz;
					--cnt;
				}
			} else
				--cnt;
			if (need_summary)
				summary();
			continue;
		}

		if (nr == 0) {
			if (files_cnt > 1) {
				--files_cnt;
				continue;
			}
			errx(1, "skip reached end of input");
		}

		/*
		 * Input error -- either EOF with no more files, or I/O error.
		 * If noerror not set die.  POSIX requires that the warning
		 * message be followed by an I/O display.
		 */
		if (ddflags & C_NOERROR) {
			if (!warned) {
				warn("%s", in.name);
				warned = 1;
				summary();
			}
			continue;
		}
		err(1, "%s", in.name);
	}
}
コード例 #4
0
ファイル: position.c プロジェクト: 2asoft/freebsd
void
pos_out(void)
{
	struct mtop t_op;
	off_t cnt;
	ssize_t n;

	/*
	 * If not a tape, try seeking on the file.  Seeking on a pipe is
	 * going to fail, but don't protect the user -- they shouldn't
	 * have specified the seek operand.
	 */
	if (out.flags & (ISSEEK | ISPIPE)) {
		errno = 0;
		if (lseek(out.fd, seek_offset(&out), SEEK_CUR) == -1 &&
		    errno != 0)
			err(1, "%s", out.name);
		return;
	}

	/* Don't try to read a really weird amount (like negative). */
	if (out.offset < 0)
		errx(1, "%s: illegal offset", "oseek/seek");

	/* If no read access, try using mtio. */
	if (out.flags & NOREAD) {
		t_op.mt_op = MTFSR;
		t_op.mt_count = out.offset;

		if (ioctl(out.fd, MTIOCTOP, &t_op) == -1)
			err(1, "%s", out.name);
		return;
	}

	/* Read it. */
	for (cnt = 0; cnt < out.offset; ++cnt) {
		if ((n = read(out.fd, out.db, out.dbsz)) > 0)
			continue;

		if (n == -1)
			err(1, "%s", out.name);

		/*
		 * If reach EOF, fill with NUL characters; first, back up over
		 * the EOF mark.  Note, cnt has not yet been incremented, so
		 * the EOF read does not count as a seek'd block.
		 */
		t_op.mt_op = MTBSR;
		t_op.mt_count = 1;
		if (ioctl(out.fd, MTIOCTOP, &t_op) == -1)
			err(1, "%s", out.name);

		while (cnt++ < out.offset) {
			n = write(out.fd, out.db, out.dbsz);
			if (n == -1)
				err(1, "%s", out.name);
			if ((size_t)n != out.dbsz)
				errx(1, "%s: write failure", out.name);
		}
		break;
	}
}