diff options
Diffstat (limited to 'shell/audio/sdl')
| -rw-r--r-- | shell/audio/sdl/sound_output.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/shell/audio/sdl/sound_output.c b/shell/audio/sdl/sound_output.c index f14bb1d..ae1ab83 100644 --- a/shell/audio/sdl/sound_output.c +++ b/shell/audio/sdl/sound_output.c @@ -1,11 +1,14 @@ #include <sys/ioctl.h> #include <stdint.h> +#include <stdbool.h> #include <fcntl.h> #include <unistd.h> #include <SDL/SDL.h> #include "sound_output.h" +#define UNDERRUN_THRESHOLD 0.5 + static int32_t BUFFSIZE; static uint8_t *buffer; static uint32_t buf_read_pos = 0; @@ -36,14 +39,20 @@ static int32_t sdl_read_buffer(uint8_t* data, int32_t len) static void sdl_write_buffer(uint8_t* data, int32_t len) { + SDL_LockAudio(); for(uint32_t i = 0; i < len; i += 4) { - if(buffered_bytes == BUFFSIZE) return; // just drop samples + while (buffered_bytes == BUFFSIZE) { + SDL_UnlockAudio(); + usleep(1000); + SDL_LockAudio(); + } *(int32_t*)((char*)(buffer + buf_write_pos)) = *(int32_t*)((char*)(data + i)); //memcpy(buffer + buf_write_pos, data + i, 4); buf_write_pos = (buf_write_pos + 4) % BUFFSIZE; buffered_bytes += 4; } + SDL_UnlockAudio(); } void sdl_callback(void *unused, uint8_t *stream, int32_t len) @@ -90,9 +99,15 @@ uint32_t Audio_Init() void Audio_Write(int16_t* restrict buffer, uint32_t buffer_size) { - SDL_LockAudio(); sdl_write_buffer(buffer, buffer_size * 4); +} + +bool Audio_Underrun_Likely() { + bool underrun_likely = false; + SDL_LockAudio(); + underrun_likely = buffered_bytes < BUFFSIZE * UNDERRUN_THRESHOLD; SDL_UnlockAudio(); + return underrun_likely; } void Audio_Close() |