Mercurial > repos > blastem
view wave.c @ 478:2e4a4188cfb0
Fix DMA fill so that it does not cause observable changes to the FIFO. Get DMA copy mostly correct from an observable ffect perspective. DMA copy probably does not reflect internal implementation still given that evidence seems to suggest no FIFO usage at all.
author | Mike Pavone <pavone@retrodev.com> |
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date | Tue, 17 Sep 2013 00:11:45 -0700 |
parents | 140af5509ce7 |
children | 6e9d1a8c1b08 |
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/* Copyright 2013 Michael Pavone This file is part of BlastEm. BlastEm is free software distributed under the terms of the GNU General Public License version 3 or greater. See COPYING for full license text. */ #include "wave.h" #include <stddef.h> #include <string.h> int wave_init(FILE * f, uint32_t sample_rate, uint16_t bits_per_sample, uint16_t num_channels) { wave_header header; memcpy(header.chunk.id, "RIFF", 4); memcpy(header.chunk.format, "WAVE", 4); header.chunk.size = 0; //This will be filled in later memcpy(header.format_header.id, "fmt ", 4); header.format_header.size = sizeof(wave_header) - (sizeof(header.chunk) + sizeof(header.data_header) + sizeof(header.format_header)); header.audio_format = 1; header.num_channels = num_channels; header.sample_rate = sample_rate; header.byte_rate = sample_rate * num_channels * (bits_per_sample/8); header.block_align = num_channels * (bits_per_sample/8); header.bits_per_sample = bits_per_sample; memcpy(header.data_header.id, "data", 4); header.data_header.size = 0;//This will be filled in later; return fwrite(&header, 1, sizeof(header), f) == sizeof(header); } int wave_finalize(FILE * f) { uint32_t size = ftell(f); fseek(f, offsetof(wave_header, chunk.size), SEEK_SET); size -= 8; if (fwrite(&size, sizeof(size), 1, f) != sizeof(size)) { fclose(f); return 0; } fseek(f, offsetof(wave_header, data_header.size), SEEK_SET); size -= 36; if (fwrite(&size, sizeof(size), 1, f)) { fclose(f); return 0; } fclose(f); return 1; }