diff options
Diffstat (limited to 'mpeglib/lib/util/audio/audioIO_Linux.cpp')
| -rw-r--r-- | mpeglib/lib/util/audio/audioIO_Linux.cpp | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/mpeglib/lib/util/audio/audioIO_Linux.cpp b/mpeglib/lib/util/audio/audioIO_Linux.cpp new file mode 100644 index 00000000..5ca9231c --- /dev/null +++ b/mpeglib/lib/util/audio/audioIO_Linux.cpp @@ -0,0 +1,220 @@ +/* this file is a part of amp software, (C) tomislav uzelac 1996,1997 + + Origional code by: tomislav uzelac + Modified by: + * Dan Nelson - BSD mods. + * Andrew Richards - moved code from audio.c and added mixer support etc + * Martin Vogt + */ + +/* Support for Linux and BSD sound devices */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdio.h> +#include "audioIO.h" +#include <stdlib.h> +#include <stdio.h> + +// +// Why all these different system cannot make a standard where this +// soundcard.h file is ? +// +#if defined(HAVE_SYS_SOUNDCARD_H) + #undef AUSIZ + #undef HAVE_SYS_SOUNDCARD_H + #include <sys/soundcard.h> +#elif defined(HAVE_MACHINE_SOUNDCARD_H) + #undef AUSIZ + #include <machine/soundcard.h> +#elif defined(__NetBSD__) + #undef AUSIZ + #include <soundcard.h> +#else + // fallback: + #include <linux/soundcard.h> +#endif + + +/* optimal fragment size */ + +int AUSIZ = 0; + +// declare these static to effectively isolate the audio device + +static int audio_fd; +static int mixer_fd; +static int volumeIoctl; + + + +int audioConstruct() { + audio_fd=-1; + mixer_fd=-1; + return true; +} + + +void audioDestruct() { + +} + + + +/* + should open the audio device, perform any special initialization +*/ +int audioOpen() { + audio_fd = open ("/dev/dsp", O_WRONLY, 0); + if (audio_fd < 0) { + perror("Unable to open the audio"); + } + + // Ok here something important if your programm forks: + if (audio_fd > 0) { + if (fcntl(audio_fd,F_SETFD,true) < 0) { + perror("fcntl socket");exit(1); + } + } + + return (audio_fd > 0); +} + +inline void audioFlush() { + if (ioctl(audio_fd, SNDCTL_DSP_RESET, 0) == -1) + perror("Unable to reset audio device\n"); +} + +/* + should close the audio device and perform any special shutdown +*/ +void audioClose() { + audioFlush(); + if (close(audio_fd) < 0) { + perror("error close audiodevice:"); + } +} + + +void audioInit(int sampleSize,int frequency, int stereo, int sign, int big) { + if( sign == 0 ) + { + fprintf(stderr, + "%s, %d: expecting signed audio data, " + "initialized unsigned (ignored)\n", + __FILE__, __LINE__ ); + } + if( big != 0 ) + { + fprintf(stderr, + "%s, %d: expecting little endian audio data, " + "initialized big endian (ignored)\n", + __FILE__, __LINE__ ); + } + + int play_format=AFMT_S16_LE; + + if (sampleSize == 8) { + play_format=AFMT_S8; + } + ioctl(audio_fd,SNDCTL_DSP_RESET,NULL); + + if (ioctl(audio_fd, SNDCTL_DSP_SETFMT,&play_format) < 0) { + perror("Unable to set required audio format\n"); + } + + /* Set 1 or 2 channels */ + stereo=(stereo ? 1 : 0); + + if (ioctl(audio_fd, SNDCTL_DSP_STEREO, &stereo) < 0) { + perror("Unable to set stereo/mono\n"); + exit(0); + } + + /* Set the output frequency */ + if (ioctl(audio_fd, SNDCTL_DSP_SPEED, &frequency) < 0) { + perror("Unable to set frequency"); + exit(0); + } + + if (ioctl(audio_fd, SNDCTL_DSP_GETBLKSIZE, &AUSIZ) == -1) { + perror("Unable to get fragment size\n"); + exit(0); + } +} + + +int getAudioBufferSize() { + struct audio_buf_info buf_info; + int buf=1024*65; + if (ioctl(audio_fd,SNDCTL_DSP_GETOSPACE,&buf_info) == -1) { + perror("ioctl getAudioBufferSize using default"); + } else { + buf=buf_info.bytes; + } + return buf; +} + + +int mixerOpen() { + int supportedMixers; + + if ((mixer_fd=open("/dev/mixer",O_RDWR)) == -1) { + perror("Unable to open mixer device"); + } + + // Ok here something important if your programm forks: + if (mixer_fd > 0) { + if (fcntl(mixer_fd,F_SETFD,true) < 0) { + perror("fcntl socket");exit(1); + } + } + + if (ioctl(mixer_fd, SOUND_MIXER_READ_DEVMASK, &supportedMixers) == -1){ + perror("Unable to get mixer info assuming master volume"); + volumeIoctl=SOUND_MIXER_WRITE_VOLUME; + } else { + if ((supportedMixers & SOUND_MASK_PCM) != 0) + volumeIoctl=SOUND_MIXER_WRITE_PCM; + else + volumeIoctl=0; + } + + return (mixer_fd > 0); +} + + +void mixerClose() { + if (mixer_fd != -1) { + close(mixer_fd); + } +} + +/* + only code this if your system can change the volume while + playing +*/ +void mixerSetVolume(int leftVolume,int rightVolume) { + int volume; + + volume=leftVolume+(rightVolume<<8); + if ((mixer_fd != -1) && (volumeIoctl!=0)) { + if (ioctl(mixer_fd, volumeIoctl, &volume) < 0) { + perror("Unable to set sound volume"); + } + } +} + + + +int audioWrite(char *buffer, int count) { + return(write(audio_fd,buffer,count)); +} + + +int getAudioFd() { + return(audio_fd); +} |