2024-09-24 14:54:57 +02:00

276 lines
7.4 KiB
C

/* --------------------------------------------------------------------------
MusicBrainz -- The Internet music metadatabase
Copyright (C) 2013 Johannes Dewender
Copyright (C) 2006 Matthias Friedrich
Copyright (C) 2000 Robert Kaye
Copyright (C) 1999 Marc E E van Woerkom
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
--------------------------------------------------------------------------- */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <assert.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <linux/cdrom.h>
#include <scsi/sg.h>
#include "discid/discid.h"
#include "discid/discid_private.h"
#include "unix.h"
/* timeout better shouldn't happen for scsi commands -> device is reset */
#define DEFAULT_TIMEOUT 30000 /* in ms */
#ifndef SG_MAX_SENSE
#define SG_MAX_SENSE 16
#endif
#define MB_DEFAULT_DEVICE "/dev/cdrom"
#define MAX_DEV_LEN 50
#if (defined(__GNUC__) && (__GNUC__ >= 4)) || defined(__clang__)
# define THREAD_LOCAL __thread
#else
# define THREAD_LOCAL
#endif
static THREAD_LOCAL char default_device[MAX_DEV_LEN] = "";
static int get_device(int number, char *device, int device_len) {
FILE *proc_file;
char *current_device;
char *lineptr = NULL;
char *saveptr = NULL;
size_t bufflen;
int i, count, counter;
int return_value = 0;
proc_file = fopen("/proc/sys/dev/cdrom/info", "r");
if (proc_file != NULL) {
/* skip to line containing device names */
do {
if (getline(&lineptr, &bufflen, proc_file) < 0) {
return 0;
}
} while (strstr(lineptr, "drive name:") == NULL);
/* count number of devices = number of tabs - 1*/
count = -1;
for (i = 0; i < strlen(lineptr); i++) {
if (lineptr[i] == '\t') count++;
}
/* go through devices, they are in reverse order */
current_device = strtok_r(lineptr, "\t", &saveptr);
/* skip column title */
current_device = strtok_r(NULL, "\t", &saveptr);
counter = count;
while (current_device != NULL && counter >= number) {
if (counter == number) {
snprintf(device, device_len,
"/dev/%s", current_device);
return_value = 1;
}
/* go to next in list */
current_device = strtok_r(NULL, "\t", &saveptr);
counter--;
}
/* trim the trailing \n for the last entry = first device */
if (return_value && device[strlen(device)-1] == '\n') {
device[strlen(device)-1] = '\0';
}
free(lineptr);
fclose(proc_file);
}
return return_value;
}
int mb_disc_unix_read_toc_header(int fd, mb_disc_toc *toc) {
struct cdrom_tochdr th;
int ret = ioctl(fd, CDROMREADTOCHDR, &th);
if ( ret < 0 )
return 0; /* error */
toc->first_track_num = th.cdth_trk0;
toc->last_track_num = th.cdth_trk1;
return 1;
}
int mb_disc_unix_read_toc_entry(int fd, int track_num, mb_disc_toc_track *track) {
struct cdrom_tocentry te;
int ret;
te.cdte_track = track_num;
te.cdte_format = CDROM_LBA;
ret = ioctl(fd, CDROMREADTOCENTRY, &te);
assert( te.cdte_format == CDROM_LBA );
if ( ret < 0 )
return 0; /* error */
track->address = te.cdte_addr.lba;
track->control = te.cdte_ctrl;
return 1;
}
char *mb_disc_get_default_device_unportable(void) {
/* prefer the default device symlink to the internal names */
if (mb_disc_unix_exists(MB_DEFAULT_DEVICE)) {
return MB_DEFAULT_DEVICE;
} else {
if (get_device(1, default_device, MAX_DEV_LEN)) {
return default_device;
} else {
return MB_DEFAULT_DEVICE;
}
}
}
void mb_disc_unix_read_mcn(int fd, mb_disc_private *disc) {
struct cdrom_mcn mcn;
memset(&mcn, 0, sizeof mcn);
if(ioctl(fd, CDROM_GET_MCN, &mcn) == -1) {
fprintf(stderr, "Warning: Unable to read the disc's media catalog number.\n");
} else {
strncpy( disc->mcn,
(const char *)mcn.medium_catalog_number,
MCN_STR_LENGTH );
}
}
/* Send a scsi command and receive data. */
static int scsi_cmd(int fd, unsigned char *cmd, int cmd_len,
unsigned char *data, int data_len) {
unsigned char sense_buffer[SG_MAX_SENSE]; /* for "error situations" */
sg_io_hdr_t io_hdr;
memset(&io_hdr, 0, sizeof io_hdr);
assert(cmd_len <= 16);
io_hdr.interface_id = 'S'; /* must always be 'S' (SCSI generic) */
io_hdr.cmd_len = cmd_len;
io_hdr.cmdp = cmd;
io_hdr.timeout = DEFAULT_TIMEOUT; /* timeout in ms */
io_hdr.sbp = sense_buffer;/* only used when status is CHECK_CONDITION */
io_hdr.mx_sb_len = sizeof sense_buffer;
io_hdr.flags = SG_FLAG_DIRECT_IO;
io_hdr.dxferp = (void*)data;
io_hdr.dxfer_len = data_len;
io_hdr.dxfer_direction = SG_DXFER_FROM_DEV;
if (ioctl(fd, SG_IO, &io_hdr) != 0) {
return errno;
} else {
return io_hdr.status; /* 0 = success */
}
}
void mb_disc_unix_read_isrc(int fd, mb_disc_private *disc, int track_num) {
int i;
unsigned char cmd[10];
unsigned char data[24];
char buffer[ISRC_STR_LENGTH+1];
memset(cmd, 0, sizeof cmd);
memset(data, 0, sizeof data);
memset(buffer, 0, sizeof buffer);
/* data read from the last appropriate sector encountered
* by a current or previous media access operation.
* The Logical Unit accesses the media when there is/was no access.
* TODO: force access at a specific block? -> no duplicate ISRCs?
*/
cmd[0] = 0x42; /* READ SUB-CHANNEL */
/* cmd[1] reserved / MSF bit (unused) */
cmd[2] = 1 << 6; /* 6th bit set (SUBQ) -> get sub-channel data */
cmd[3] = 0x03; /* get ISRC (ADR 3, Q sub-channel Mode-3) */
/* 4+5 reserved */
cmd[6] = track_num;
/* cmd[7] = upper byte of the transfer length */
cmd[8] = sizeof data; /* transfer length in bytes (4 header, 20 data)*/
/* cmd[9] = control byte */
if (scsi_cmd(fd, cmd, sizeof cmd, data, sizeof data) != 0) {
fprintf(stderr, "Warning: Cannot get ISRC code for track %d\n",
track_num);
return;
}
/* data[1:4] = sub-q channel data header (audio status, data length) */
if (data[8] & (1 << 7)) { /* TCVAL is set -> ISRCs valid */
for (i = 0; i < ISRC_STR_LENGTH; i++) {
buffer[i] = data[9 + i];
}
buffer[ISRC_STR_LENGTH] = 0;
strncpy(disc->isrc[track_num], buffer, ISRC_STR_LENGTH);
}
/* data[21:23] = zero, AFRAME, reserved */
}
int mb_disc_has_feature_unportable(enum discid_feature feature) {
switch(feature) {
case DISCID_FEATURE_READ:
case DISCID_FEATURE_MCN:
case DISCID_FEATURE_ISRC:
return 1;
default:
return 0;
}
}
int mb_disc_read_unportable(mb_disc_private *disc, const char *device,
unsigned int features) {
char device_name[MAX_DEV_LEN] = "";
int device_number;
device_number = (int) strtol(device, NULL, 10);
if (device_number > 0) {
if(!get_device(device_number, device_name, MAX_DEV_LEN)) {
snprintf(disc->error_msg, MB_ERROR_MSG_LENGTH,
"cannot find cd device with the number '%d'",
device_number);
return 0;
} else {
return mb_disc_unix_read(disc, device_name, features);
}
} else {
return mb_disc_unix_read(disc, device, features);
}
}
/* EOF */