FreeCalypso > hg > gsm-codec-lib
view libtest/wavreader.c @ 282:9ee8ad3d4d30
frtest: rm gsmfr-hand-test and gsmfr-max-out utils
These hack programs were never properly documented and were written
only as part of a debug chase, in pursuit of a bug that ultimately
turned out to be in our then-hacky patch to osmo-bts-sysmo,
before beginning of proper patches in Osmocom. These hack programs
need to be dropped from the present sw package because they depend
on old libgsm, and we are eliminating that dependency.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sun, 14 Apr 2024 05:44:47 +0000 |
parents | 634df6435e16 |
children |
line wrap: on
line source
/* ------------------------------------------------------------------ * Copyright (C) 2009 Martin Storsjo * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. * See the License for the specific language governing permissions * and limitations under the License. * ------------------------------------------------------------------- */ #include "wavreader.h" #include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdint.h> #define TAG(a, b, c, d) (((a) << 24) | ((b) << 16) | ((c) << 8) | (d)) struct wav_reader { FILE *wav; uint32_t data_length; int format; int sample_rate; int bits_per_sample; int channels; int byte_rate; int block_align; }; static uint32_t read_tag(struct wav_reader* wr) { uint32_t tag = 0; tag = (tag << 8) | fgetc(wr->wav); tag = (tag << 8) | fgetc(wr->wav); tag = (tag << 8) | fgetc(wr->wav); tag = (tag << 8) | fgetc(wr->wav); return tag; } static uint32_t read_int32(struct wav_reader* wr) { uint32_t value = 0; value |= fgetc(wr->wav) << 0; value |= fgetc(wr->wav) << 8; value |= fgetc(wr->wav) << 16; value |= fgetc(wr->wav) << 24; return value; } static uint16_t read_int16(struct wav_reader* wr) { uint16_t value = 0; value |= fgetc(wr->wav) << 0; value |= fgetc(wr->wav) << 8; return value; } void* wav_read_open(const char *filename) { struct wav_reader* wr = (struct wav_reader*) malloc(sizeof(*wr)); long data_pos = 0; memset(wr, 0, sizeof(*wr)); wr->wav = fopen(filename, "rb"); if (wr->wav == NULL) { free(wr); return NULL; } while (1) { uint32_t tag, tag2, length; tag = read_tag(wr); if (feof(wr->wav)) break; length = read_int32(wr); if (tag != TAG('R', 'I', 'F', 'F') || length < 4) { fseek(wr->wav, length, SEEK_CUR); continue; } tag2 = read_tag(wr); length -= 4; if (tag2 != TAG('W', 'A', 'V', 'E')) { fseek(wr->wav, length, SEEK_CUR); continue; } // RIFF chunk found, iterate through it while (length >= 8) { uint32_t subtag, sublength; subtag = read_tag(wr); if (feof(wr->wav)) break; sublength = read_int32(wr); length -= 8; if (length < sublength) break; if (subtag == TAG('f', 'm', 't', ' ')) { if (sublength < 16) { // Insufficient data for 'fmt ' break; } wr->format = read_int16(wr); wr->channels = read_int16(wr); wr->sample_rate = read_int32(wr); wr->byte_rate = read_int32(wr); wr->block_align = read_int16(wr); wr->bits_per_sample = read_int16(wr); fseek(wr->wav, sublength - 16, SEEK_CUR); } else if (subtag == TAG('d', 'a', 't', 'a')) { data_pos = ftell(wr->wav); wr->data_length = sublength; fseek(wr->wav, sublength, SEEK_CUR); } else { fseek(wr->wav, sublength, SEEK_CUR); } length -= sublength; } if (length > 0) { // Bad chunk? fseek(wr->wav, length, SEEK_CUR); } } fseek(wr->wav, data_pos, SEEK_SET); return wr; } void wav_read_close(void* obj) { struct wav_reader* wr = (struct wav_reader*) obj; fclose(wr->wav); free(wr); } int wav_get_header(void* obj, int* format, int* channels, int* sample_rate, int* bits_per_sample, unsigned int* data_length) { struct wav_reader* wr = (struct wav_reader*) obj; if (format) *format = wr->format; if (channels) *channels = wr->channels; if (sample_rate) *sample_rate = wr->sample_rate; if (bits_per_sample) *bits_per_sample = wr->bits_per_sample; if (data_length) *data_length = wr->data_length; return wr->format && wr->sample_rate; } int wav_read_data(void* obj, unsigned char* data, unsigned int length) { struct wav_reader* wr = (struct wav_reader*) obj; int n; if (wr->wav == NULL) return -1; if (length > wr->data_length) length = wr->data_length; n = fread(data, 1, length, wr->wav); wr->data_length -= length; return n; }