mpv/stream/stream_dvd_common.c

/*
 * This file is part of mpv.
 *
 * mpv is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * mpv is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with mpv.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <fcntl.h>
#include <inttypes.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <assert.h>

#include <libavutil/intreadwrite.h>

#include "config.h"

#include <dvdread/ifo_types.h>

#ifdef __FreeBSD__
#include <sys/cdrio.h>
#endif

#ifdef __linux__
#include <linux/cdrom.h>
#include <scsi/sg.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#endif

#include "osdep/io.h"

#include "common/msg.h"
#include "misc/bstr.h"
#include "stream_dvd_common.h"

const char * const dvd_audio_stream_types[8] = { "ac3","unknown","mpeg1","mpeg2ext","lpcm","unknown","dts" };
const char * const dvd_audio_stream_channels[6] = { "mono", "stereo", "unknown", "unknown", "5.1/6.1", "5.1" };

void dvd_set_speed(stream_t *stream, char *device, unsigned speed)
{
#if defined(__linux__) && defined(SG_IO) && defined(GPCMD_SET_STREAMING)
  int fd;
  unsigned char buffer[28];
  unsigned char cmd[12];
  struct sg_io_hdr sghdr;
  struct stat st;

  memset(&st, 0, sizeof(st));

  if (stat(device, &st) == -1) return;

  if (!S_ISBLK(st.st_mode)) return; /* not a block device */

  switch (speed) {
  case 0: /* don't touch speed setting */
    return;
  case -1: /* restore default value */
    MP_INFO(stream, "Restoring DVD speed... ");
    break;
  default: /* limit to <speed> KB/s */
    // speed < 100 is multiple of DVD single speed (1350KB/s)
    if (speed < 100)
      speed *= 1350;
    MP_INFO(stream, "Limiting DVD speed to %dKB/s... ", speed);
    break;
  }

  memset(&sghdr, 0, sizeof(sghdr));
  sghdr.interface_id = 'S';
  sghdr.timeout = 5000;
  sghdr.dxfer_direction = SG_DXFER_TO_DEV;
  sghdr.dxfer_len = sizeof(buffer);
  sghdr.dxferp = buffer;
  sghdr.cmd_len = sizeof(cmd);
  sghdr.cmdp = cmd;

  memset(cmd, 0, sizeof(cmd));
  cmd[0] = GPCMD_SET_STREAMING;
  cmd[10] = sizeof(buffer);

  memset(buffer, 0, sizeof(buffer));
  /* first sector 0, last sector 0xffffffff */
  AV_WB32(buffer + 8, 0xffffffff);
  if (speed == -1)
    buffer[0] = 4; /* restore default */
  else {
    /* <speed> kilobyte */
    AV_WB32(buffer + 12, speed);
    AV_WB32(buffer + 20, speed);
  }
  /* 1 second */
  AV_WB16(buffer + 18, 1000);
  AV_WB16(buffer + 26, 1000);

  fd = open(device, O_RDWR | O_NONBLOCK | O_CLOEXEC);
  if (fd == -1) {
    MP_INFO(stream, "Couldn't open DVD device for writing, changing DVD speed needs write access.\n");
    return;
  }

  if (ioctl(fd, SG_IO, &sghdr) < 0)
    MP_INFO(stream, "failed\n");
  else
    MP_INFO(stream, "successful\n");

  close(fd);
#endif
}

/**
\brief Converts DVD time structure to milliseconds.
\param *dev the DVD time structure to convert
\return returns the time in milliseconds
*/
int mp_dvdtimetomsec(dvd_time_t *dt)
{
  int framerates[4] = {0, 2500, 0, 2997};
  int framerate = framerates[(dt->frame_u & 0xc0) >> 6];
  int msec = (((dt->hour & 0xf0) >> 3) * 5 + (dt->hour & 0x0f)) * 3600000;
  msec += (((dt->minute & 0xf0) >> 3) * 5 + (dt->minute & 0x0f)) * 60000;
  msec += (((dt->second & 0xf0) >> 3) * 5 + (dt->second & 0x0f)) * 1000;
  if(framerate > 0)
    msec += (((dt->frame_u & 0x30) >> 3) * 5 + (dt->frame_u & 0x0f)) * 100000 / framerate;
  return msec;
}

// Check if this is likely to be an .ifo or similar file.
int dvd_probe(const char *path, const char *ext, const char *sig)
{
    if (!bstr_case_endswith(bstr0(path), bstr0(ext)))
        return false;

    FILE *temp = fopen(path, "rb");
    if (!temp)
        return false;

    bool r = false;

    char data[50];

    assert(strlen(sig) <= sizeof(data));

    if (fread(data, 50, 1, temp) == 1) {
        if (memcmp(data, sig, strlen(sig)) == 0)
            r = true;
    }

    fclose(temp);
    return r;
}