| /* |
| Simple DirectMedia Layer |
| Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org> |
| |
| This software is provided 'as-is', without any express or implied |
| warranty. In no event will the authors be held liable for any damages |
| arising from the use of this software. |
| |
| Permission is granted to anyone to use this software for any purpose, |
| including commercial applications, and to alter it and redistribute it |
| freely, subject to the following restrictions: |
| |
| 1. The origin of this software must not be misrepresented; you must not |
| claim that you wrote the original software. If you use this software |
| in a product, an acknowledgment in the product documentation would be |
| appreciated but is not required. |
| 2. Altered source versions must be plainly marked as such, and must not be |
| misrepresented as being the original software. |
| 3. This notice may not be removed or altered from any source distribution. |
| */ |
| #include "../../SDL_internal.h" |
| |
| #if SDL_AUDIO_DRIVER_DISK |
| |
| /* Output raw audio data to a file. */ |
| |
| #if HAVE_STDIO_H |
| #include <stdio.h> |
| #endif |
| |
| #include "SDL_rwops.h" |
| #include "SDL_timer.h" |
| #include "SDL_audio.h" |
| #include "../SDL_audio_c.h" |
| #include "SDL_diskaudio.h" |
| #include "SDL_log.h" |
| |
| /* !!! FIXME: these should be SDL hints, not environment variables. */ |
| /* environment variables and defaults. */ |
| #define DISKENVR_OUTFILE "SDL_DISKAUDIOFILE" |
| #define DISKDEFAULT_OUTFILE "sdlaudio.raw" |
| #define DISKENVR_INFILE "SDL_DISKAUDIOFILEIN" |
| #define DISKDEFAULT_INFILE "sdlaudio-in.raw" |
| #define DISKENVR_IODELAY "SDL_DISKAUDIODELAY" |
| |
| /* This function waits until it is possible to write a full sound buffer */ |
| static void |
| DISKAUDIO_WaitDevice(_THIS) |
| { |
| SDL_Delay(this->hidden->io_delay); |
| } |
| |
| static void |
| DISKAUDIO_PlayDevice(_THIS) |
| { |
| const size_t written = SDL_RWwrite(this->hidden->io, |
| this->hidden->mixbuf, |
| 1, this->spec.size); |
| |
| /* If we couldn't write, assume fatal error for now */ |
| if (written != this->spec.size) { |
| SDL_OpenedAudioDeviceDisconnected(this); |
| } |
| #ifdef DEBUG_AUDIO |
| fprintf(stderr, "Wrote %d bytes of audio data\n", written); |
| #endif |
| } |
| |
| static Uint8 * |
| DISKAUDIO_GetDeviceBuf(_THIS) |
| { |
| return (this->hidden->mixbuf); |
| } |
| |
| static int |
| DISKAUDIO_CaptureFromDevice(_THIS, void *buffer, int buflen) |
| { |
| struct SDL_PrivateAudioData *h = this->hidden; |
| const int origbuflen = buflen; |
| |
| SDL_Delay(h->io_delay); |
| |
| if (h->io) { |
| const size_t br = SDL_RWread(h->io, buffer, 1, buflen); |
| buflen -= (int) br; |
| buffer = ((Uint8 *) buffer) + br; |
| if (buflen > 0) { /* EOF (or error, but whatever). */ |
| SDL_RWclose(h->io); |
| h->io = NULL; |
| } |
| } |
| |
| /* if we ran out of file, just write silence. */ |
| SDL_memset(buffer, this->spec.silence, buflen); |
| |
| return origbuflen; |
| } |
| |
| static void |
| DISKAUDIO_FlushCapture(_THIS) |
| { |
| /* no op...we don't advance the file pointer or anything. */ |
| } |
| |
| |
| static void |
| DISKAUDIO_CloseDevice(_THIS) |
| { |
| if (this->hidden->io != NULL) { |
| SDL_RWclose(this->hidden->io); |
| } |
| SDL_free(this->hidden->mixbuf); |
| SDL_free(this->hidden); |
| } |
| |
| |
| static const char * |
| get_filename(const int iscapture, const char *devname) |
| { |
| if (devname == NULL) { |
| devname = SDL_getenv(iscapture ? DISKENVR_INFILE : DISKENVR_OUTFILE); |
| if (devname == NULL) { |
| devname = iscapture ? DISKDEFAULT_INFILE : DISKDEFAULT_OUTFILE; |
| } |
| } |
| return devname; |
| } |
| |
| static int |
| DISKAUDIO_OpenDevice(_THIS, void *handle, const char *devname, int iscapture) |
| { |
| /* handle != NULL means "user specified the placeholder name on the fake detected device list" */ |
| const char *fname = get_filename(iscapture, handle ? NULL : devname); |
| const char *envr = SDL_getenv(DISKENVR_IODELAY); |
| |
| this->hidden = (struct SDL_PrivateAudioData *) |
| SDL_malloc(sizeof(*this->hidden)); |
| if (this->hidden == NULL) { |
| return SDL_OutOfMemory(); |
| } |
| SDL_zerop(this->hidden); |
| |
| if (envr != NULL) { |
| this->hidden->io_delay = SDL_atoi(envr); |
| } else { |
| this->hidden->io_delay = ((this->spec.samples * 1000) / this->spec.freq); |
| } |
| |
| /* Open the audio device */ |
| this->hidden->io = SDL_RWFromFile(fname, iscapture ? "rb" : "wb"); |
| if (this->hidden->io == NULL) { |
| return -1; |
| } |
| |
| /* Allocate mixing buffer */ |
| if (!iscapture) { |
| this->hidden->mixbuf = (Uint8 *) SDL_malloc(this->spec.size); |
| if (this->hidden->mixbuf == NULL) { |
| return SDL_OutOfMemory(); |
| } |
| SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size); |
| } |
| |
| SDL_LogCritical(SDL_LOG_CATEGORY_AUDIO, |
| "You are using the SDL disk i/o audio driver!\n"); |
| SDL_LogCritical(SDL_LOG_CATEGORY_AUDIO, |
| " %s file [%s].\n", iscapture ? "Reading from" : "Writing to", |
| fname); |
| |
| /* We're ready to rock and roll. :-) */ |
| return 0; |
| } |
| |
| static void |
| DISKAUDIO_DetectDevices(void) |
| { |
| SDL_AddAudioDevice(SDL_FALSE, DEFAULT_OUTPUT_DEVNAME, (void *) 0x1); |
| SDL_AddAudioDevice(SDL_TRUE, DEFAULT_INPUT_DEVNAME, (void *) 0x2); |
| } |
| |
| static int |
| DISKAUDIO_Init(SDL_AudioDriverImpl * impl) |
| { |
| /* Set the function pointers */ |
| impl->OpenDevice = DISKAUDIO_OpenDevice; |
| impl->WaitDevice = DISKAUDIO_WaitDevice; |
| impl->PlayDevice = DISKAUDIO_PlayDevice; |
| impl->GetDeviceBuf = DISKAUDIO_GetDeviceBuf; |
| impl->CaptureFromDevice = DISKAUDIO_CaptureFromDevice; |
| impl->FlushCapture = DISKAUDIO_FlushCapture; |
| |
| impl->CloseDevice = DISKAUDIO_CloseDevice; |
| impl->DetectDevices = DISKAUDIO_DetectDevices; |
| |
| impl->AllowsArbitraryDeviceNames = 1; |
| impl->HasCaptureSupport = SDL_TRUE; |
| |
| return 1; /* this audio target is available. */ |
| } |
| |
| AudioBootStrap DISKAUDIO_bootstrap = { |
| "disk", "direct-to-disk audio", DISKAUDIO_Init, 1 |
| }; |
| |
| #endif /* SDL_AUDIO_DRIVER_DISK */ |
| |
| /* vi: set ts=4 sw=4 expandtab: */ |