Initial community commit

Src/external_dependencies/libdiscid-0.6.2/src/disc_linux.c

@@ -0,0 +1,275 @@
+/* --------------------------------------------------------------------------
+
+   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 */