diff options
Diffstat (limited to 'distrib/sdl-1.2.15/src/audio/esd/SDL_esdaudio.c')
| -rw-r--r-- | distrib/sdl-1.2.15/src/audio/esd/SDL_esdaudio.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/audio/esd/SDL_esdaudio.c b/distrib/sdl-1.2.15/src/audio/esd/SDL_esdaudio.c new file mode 100644 index 0000000..f54b0ea --- /dev/null +++ b/distrib/sdl-1.2.15/src/audio/esd/SDL_esdaudio.c @@ -0,0 +1,323 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2012 Sam Lantinga + + 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 St, Fifth Floor, Boston, MA 02110-1301 USA + + Sam Lantinga + slouken@libsdl.org +*/ +#include "SDL_config.h" + +/* Allow access to an ESD network stream mixing buffer */ + +#include <sys/types.h> +#include <unistd.h> +#include <signal.h> +#include <errno.h> +#include <esd.h> + +#include "SDL_timer.h" +#include "SDL_audio.h" +#include "../SDL_audiomem.h" +#include "../SDL_audio_c.h" +#include "../SDL_audiodev_c.h" +#include "SDL_esdaudio.h" + +#ifdef SDL_AUDIO_DRIVER_ESD_DYNAMIC +#include "SDL_name.h" +#include "SDL_loadso.h" +#else +#define SDL_NAME(X) X +#endif + +/* The tag name used by ESD audio */ +#define ESD_DRIVER_NAME "esd" + +/* Audio driver functions */ +static int ESD_OpenAudio(_THIS, SDL_AudioSpec *spec); +static void ESD_WaitAudio(_THIS); +static void ESD_PlayAudio(_THIS); +static Uint8 *ESD_GetAudioBuf(_THIS); +static void ESD_CloseAudio(_THIS); + +#ifdef SDL_AUDIO_DRIVER_ESD_DYNAMIC + +static const char *esd_library = SDL_AUDIO_DRIVER_ESD_DYNAMIC; +static void *esd_handle = NULL; +static int esd_loaded = 0; + +static int (*SDL_NAME(esd_open_sound))( const char *host ); +static int (*SDL_NAME(esd_close))( int esd ); +static int (*SDL_NAME(esd_play_stream))( esd_format_t format, int rate, + const char *host, const char *name ); +static struct { + const char *name; + void **func; +} esd_functions[] = { + { "esd_open_sound", (void **)&SDL_NAME(esd_open_sound) }, + { "esd_close", (void **)&SDL_NAME(esd_close) }, + { "esd_play_stream", (void **)&SDL_NAME(esd_play_stream) }, +}; + +static void UnloadESDLibrary() +{ + if ( esd_loaded ) { + SDL_UnloadObject(esd_handle); + esd_handle = NULL; + esd_loaded = 0; + } +} + +static int LoadESDLibrary(void) +{ + int i, retval = -1; + + esd_handle = SDL_LoadObject(esd_library); + if ( esd_handle ) { + esd_loaded = 1; + retval = 0; + for ( i=0; i<SDL_arraysize(esd_functions); ++i ) { + *esd_functions[i].func = SDL_LoadFunction(esd_handle, esd_functions[i].name); + if ( !*esd_functions[i].func ) { + retval = -1; + UnloadESDLibrary(); + break; + } + } + } + return retval; +} + +#else + +static void UnloadESDLibrary() +{ + return; +} + +static int LoadESDLibrary(void) +{ + return 0; +} + +#endif /* SDL_AUDIO_DRIVER_ESD_DYNAMIC */ + +/* Audio driver bootstrap functions */ + +static int Audio_Available(void) +{ + int connection; + int available; + + available = 0; + if ( LoadESDLibrary() < 0 ) { + return available; + } + connection = SDL_NAME(esd_open_sound)(NULL); + if ( connection >= 0 ) { + available = 1; + SDL_NAME(esd_close)(connection); + } + UnloadESDLibrary(); + return(available); +} + +static void Audio_DeleteDevice(SDL_AudioDevice *device) +{ + SDL_free(device->hidden); + SDL_free(device); + UnloadESDLibrary(); +} + +static SDL_AudioDevice *Audio_CreateDevice(int devindex) +{ + SDL_AudioDevice *this; + + /* Initialize all variables that we clean on shutdown */ + LoadESDLibrary(); + this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice)); + if ( this ) { + SDL_memset(this, 0, (sizeof *this)); + this->hidden = (struct SDL_PrivateAudioData *) + SDL_malloc((sizeof *this->hidden)); + } + if ( (this == NULL) || (this->hidden == NULL) ) { + SDL_OutOfMemory(); + if ( this ) { + SDL_free(this); + } + return(0); + } + SDL_memset(this->hidden, 0, (sizeof *this->hidden)); + audio_fd = -1; + + /* Set the function pointers */ + this->OpenAudio = ESD_OpenAudio; + this->WaitAudio = ESD_WaitAudio; + this->PlayAudio = ESD_PlayAudio; + this->GetAudioBuf = ESD_GetAudioBuf; + this->CloseAudio = ESD_CloseAudio; + + this->free = Audio_DeleteDevice; + + return this; +} + +AudioBootStrap ESD_bootstrap = { + ESD_DRIVER_NAME, "Enlightened Sound Daemon", + Audio_Available, Audio_CreateDevice +}; + +/* This function waits until it is possible to write a full sound buffer */ +static void ESD_WaitAudio(_THIS) +{ + Sint32 ticks; + + /* Check to see if the thread-parent process is still alive */ + { static int cnt = 0; + /* Note that this only works with thread implementations + that use a different process id for each thread. + */ + if (parent && (((++cnt)%10) == 0)) { /* Check every 10 loops */ + if ( kill(parent, 0) < 0 ) { + this->enabled = 0; + } + } + } + + /* Use timer for general audio synchronization */ + ticks = ((Sint32)(next_frame - SDL_GetTicks()))-FUDGE_TICKS; + if ( ticks > 0 ) { + SDL_Delay(ticks); + } +} + +static void ESD_PlayAudio(_THIS) +{ + int written; + + /* Write the audio data, checking for EAGAIN on broken audio drivers */ + do { + written = write(audio_fd, mixbuf, mixlen); + if ( (written < 0) && ((errno == 0) || (errno == EAGAIN)) ) { + SDL_Delay(1); /* Let a little CPU time go by */ + } + } while ( (written < 0) && + ((errno == 0) || (errno == EAGAIN) || (errno == EINTR)) ); + + /* Set the next write frame */ + next_frame += frame_ticks; + + /* If we couldn't write, assume fatal error for now */ + if ( written < 0 ) { + this->enabled = 0; + } +} + +static Uint8 *ESD_GetAudioBuf(_THIS) +{ + return(mixbuf); +} + +static void ESD_CloseAudio(_THIS) +{ + if ( mixbuf != NULL ) { + SDL_FreeAudioMem(mixbuf); + mixbuf = NULL; + } + if ( audio_fd >= 0 ) { + SDL_NAME(esd_close)(audio_fd); + audio_fd = -1; + } +} + +/* Try to get the name of the program */ +static char *get_progname(void) +{ + char *progname = NULL; +#ifdef __LINUX__ + FILE *fp; + static char temp[BUFSIZ]; + + SDL_snprintf(temp, SDL_arraysize(temp), "/proc/%d/cmdline", getpid()); + fp = fopen(temp, "r"); + if ( fp != NULL ) { + if ( fgets(temp, sizeof(temp)-1, fp) ) { + progname = SDL_strrchr(temp, '/'); + if ( progname == NULL ) { + progname = temp; + } else { + progname = progname+1; + } + } + fclose(fp); + } +#endif + return(progname); +} + +static int ESD_OpenAudio(_THIS, SDL_AudioSpec *spec) +{ + esd_format_t format; + + /* Convert audio spec to the ESD audio format */ + format = (ESD_STREAM | ESD_PLAY); + switch ( spec->format & 0xFF ) { + case 8: + format |= ESD_BITS8; + break; + case 16: + format |= ESD_BITS16; + break; + default: + SDL_SetError("Unsupported ESD audio format"); + return(-1); + } + if ( spec->channels == 1 ) { + format |= ESD_MONO; + } else { + format |= ESD_STEREO; + } +#if 0 + spec->samples = ESD_BUF_SIZE; /* Darn, no way to change this yet */ +#endif + + /* Open a connection to the ESD audio server */ + audio_fd = SDL_NAME(esd_play_stream)(format, spec->freq, NULL, get_progname()); + if ( audio_fd < 0 ) { + SDL_SetError("Couldn't open ESD connection"); + return(-1); + } + + /* Calculate the final parameters for this audio specification */ + SDL_CalculateAudioSpec(spec); + frame_ticks = (float)(spec->samples*1000)/spec->freq; + next_frame = SDL_GetTicks()+frame_ticks; + + /* Allocate mixing buffer */ + mixlen = spec->size; + mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen); + if ( mixbuf == NULL ) { + return(-1); + } + SDL_memset(mixbuf, spec->silence, spec->size); + + /* Get the parent process id (we're the parent of the audio thread) */ + parent = getpid(); + + /* We're ready to rock and roll. :-) */ + return(0); +} |