Fix OSS compilation due to redefined audio variable.

/*
 * lingot, a musical instrument tuner.
 *
 * Copyright (C) 2004-2011  Ibán Cereijo Graña, Jairo Chapela Martínez.
 *
 * This file is part of lingot.
 *
 * lingot 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.
 *
 * lingot 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 lingot; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef OSS
#include <sys/soundcard.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/errno.h>
#endif
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#include "lingot-msg.h"
#include "lingot-defs.h"
#include "lingot-audio-oss.h"
#include "lingot-i18n.h"

LingotAudioHandler* lingot_audio_oss_new(char* device, int sample_rate) {

	LingotAudioHandler* audio = NULL;

#ifdef OSS
	int channels = 1;
	int format = SAMPLE_FORMAT;
	char error_message[100];
	const char* exception;

	LingotAudioHandler* audio = malloc(sizeof(LingotAudioHandler));

	audio->audio_system = AUDIO_SYSTEM_OSS;
	audio->dsp = open(device, O_RDONLY);
	audio->read_buffer_size = 128; // TODO: size up
	strcpy(audio->device, device);

	try {

		if (audio->dsp < 0) {
			sprintf(error_message, _("Unable to open audio device %s.\n%s."),
					device, strerror(errno));
			throw(error_message);
		}

		//if (ioctl(audio->dsp, SOUND_PCM_READ_CHANNELS, &channels) < 0)
		if (ioctl(audio->dsp, SNDCTL_DSP_CHANNELS, &channels) < 0) {
			sprintf(error_message, _("Error setting number of channels.\n%s."),
					strerror(errno));
			throw(error_message);
		}

		// sample size
		//if (ioctl(audio->dsp, SOUND_PCM_SETFMT, &format) < 0)
		if (ioctl(audio->dsp, SNDCTL_DSP_SETFMT, &format) < 0) {
			sprintf(error_message, _("Error setting bits per sample.\n%s."),
					strerror(errno));
			throw(error_message);
		}

		int fragment_size = 1;
		int DMA_buffer_size = 512;
		int param = 0;

		for (param = 0; fragment_size < DMA_buffer_size; param++)
			fragment_size <<= 1;

		param |= 0x00ff0000;

		if (ioctl(audio->dsp, SNDCTL_DSP_SETFRAGMENT, &param) < 0) {
			sprintf(error_message, _("Error setting DMA buffer size.\n%s."),
					strerror(errno));
			throw(error_message);
		}

		if (ioctl(audio->dsp, SNDCTL_DSP_SPEED, &sample_rate) < 0) {
			sprintf(error_message, _("Error setting sample rate.\n%s."),
					strerror(errno));
			throw(error_message);
		}

		audio->real_sample_rate = sample_rate;
		audio->read_buffer = malloc(audio->read_buffer_size
				* sizeof(SAMPLE_TYPE));
		memset(audio->read_buffer, 0, audio->read_buffer_size
				* sizeof(SAMPLE_TYPE));

	} catch {
		close(audio->dsp);
		free(audio);
		audio = NULL;
		lingot_msg_add_error(exception);
	}

#	else
	lingot_msg_add_error(
			_("The application has not been built with OSS support"));
#	endif

	return audio;
}

void lingot_audio_oss_destroy(LingotAudioHandler* audio) {
#ifdef OSS
	if (audio != NULL) {
		close(audio->dsp);
		free(audio->read_buffer);
	}
#endif
}

int lingot_audio_oss_read(LingotAudioHandler* audio) {
#ifdef OSS
	int i;
	int read_size;

	read_size = read(audio->dsp, audio->read_buffer, audio->read_buffer_size
			* sizeof(SAMPLE_TYPE));

	//	if (rand() < 0.001 * RAND_MAX)
	//		read_size = 0;

	if (read_size != audio->read_buffer_size * sizeof(SAMPLE_TYPE)) {
		char buff[100];
		sprintf(buff, _("Read from audio interface failed.\n%s."), strerror(
				errno));
		lingot_msg_add_error(buff);
		return -1;
	}

	// float point conversion
	for (i = 0; i < audio->read_buffer_size; i++) {
		audio->flt_read_buffer[i] = audio->read_buffer[i];
	}

#endif

	return 0;
}

LingotAudioSystemProperties* lingot_audio_oss_get_audio_system_properties(
		audio_system_t audio_system) {

	LingotAudioSystemProperties* result =
			(LingotAudioSystemProperties*) malloc(1
					* sizeof(LingotAudioSystemProperties));

	// TODO
	result->forced_sample_rate = 0;
	result->n_devices = 0;
	result->devices = NULL;

	result->n_sample_rates = 5;
	result->sample_rates = malloc(result->n_sample_rates * sizeof(int));
	result->sample_rates[0] = 8000;
	result->sample_rates[1] = 11025;
	result->sample_rates[2] = 22050;
	result->sample_rates[3] = 44100;
	result->sample_rates[4] = 48000;

	return result;
}