Easily read and write WAV sound files.

wav.c

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

typedef struct riff {
	unsigned char chunkID[4];
	unsigned int chunkSize;
	unsigned char format[4];
	
} Riff;

typedef struct fmt {
	unsigned char chunkID[4];
	unsigned int chunkSize;
	unsigned short audioFormat;
	unsigned short numChannels;
	unsigned int sampleRate;
	unsigned int byteRate;
	unsigned short blockAlign;
	unsigned short bitsPerSample;
	
} Fmt;

typedef struct data {
	unsigned char chunkID[4];
	unsigned int chunkSize;
	void *sound;
	
} Data;

typedef struct wave {
	Riff riff;
	Fmt fmt;
	Data data;
	
} Wave;

Wave *LoadWAV(const char *file) {
	FILE *fp;
	Wave *audio;
	unsigned int size;
	
	if ((fp = fopen(file, "rb")) == NULL) return NULL;
	
	if ((audio = malloc(sizeof(Wave))) == NULL)
	{
		fclose(fp);
		return NULL;
	}
	
	fread(audio->riff.chunkID,           sizeof(audio->riff.chunkID), 1, fp);
	fread(&audio->riff.chunkSize,        sizeof(audio->riff.chunkSize), 1, fp);
	fread(audio->riff.format,            sizeof(audio->riff.format), 1, fp);

	fread(audio->fmt.chunkID,            sizeof(audio->fmt.chunkID), 1, fp);
	fread(&audio->fmt.chunkSize,         sizeof(audio->fmt.chunkSize), 1, fp);
	fread(&audio->fmt.audioFormat,       sizeof(audio->fmt.audioFormat), 1, fp);
	fread(&audio->fmt.numChannels,       sizeof(audio->fmt.numChannels), 1, fp);
	fread(&audio->fmt.sampleRate,        sizeof(audio->fmt.sampleRate), 1, fp);
	fread(&audio->fmt.byteRate,          sizeof(audio->fmt.byteRate), 1, fp);
	fread(&audio->fmt.blockAlign,        sizeof(audio->fmt.blockAlign), 1, fp);
	fread(&audio->fmt.bitsPerSample,     sizeof(audio->fmt.bitsPerSample), 1, fp);

	fread(audio->data.chunkID,           sizeof(audio->data.chunkID), 1, fp);
	fread(&audio->data.chunkSize,        sizeof(audio->data.chunkSize), 1, fp);
	
	size = audio->data.chunkSize;
	audio->data.sound = malloc(size);
	fread(audio->data.sound, size, 1, fp);
	
	fclose(fp);
	
	return audio;
}

void FreeWAV(Wave *audio) {
	free(audio->data.sound);
	free(audio);
}

bool WriteWAV(const char *file, Wave audio) {
	FILE *fp;
	
	if ((fp = fopen(file, "wb")) == NULL) return false;
	
  	fwrite(audio.riff.chunkID,           sizeof(audio.riff.chunkID), 1, fp);
  	fwrite(&audio.riff.chunkSize,        sizeof(audio.riff.chunkSize), 1, fp);
  	fwrite(audio.riff.format,            sizeof(audio.riff.format), 1, fp);

  	fwrite(audio.fmt.chunkID,            sizeof(audio.fmt.chunkID), 1, fp);
  	fwrite(&audio.fmt.chunkSize,         sizeof(audio.fmt.chunkSize), 1, fp);
  	fwrite(&audio.fmt.audioFormat,       sizeof(audio.fmt.audioFormat), 1, fp);
  	fwrite(&audio.fmt.numChannels,       sizeof(audio.fmt.numChannels), 1, fp);
  	fwrite(&audio.fmt.sampleRate,        sizeof(audio.fmt.sampleRate), 1, fp);
  	fwrite(&audio.fmt.byteRate,          sizeof(audio.fmt.byteRate), 1, fp);
  	fwrite(&audio.fmt.blockAlign,        sizeof(audio.fmt.blockAlign), 1, fp);
  	fwrite(&audio.fmt.bitsPerSample,     sizeof(audio.fmt.bitsPerSample), 1, fp);

  	fwrite(audio.data.chunkID,           sizeof(audio.data.chunkID), 1, fp);
  	fwrite(&audio.data.chunkSize,        sizeof(audio.data.chunkSize), 1, fp);
	
	fwrite(audio.data.sound, audio.data.chunkSize, 1, fp);
	
	fclose(fp);
	
	return true;
}

/*///////////////////////////////////
	
		Testing:
		
///////////////////////////////////*/

int main(void) {
	
	Wave *audio = LoadWAV("audio.wav");
	if (audio == NULL) return 1;
	
	printf("%s\n", (audio->fmt.numChannels == 1) ? "Mono" : "Stereo");
	printf("audio size: %i bits\n", audio->riff.chunkSize);
	printf("sample rate: %i\n", audio->fmt.sampleRate);
	
	if (WriteWAV("audio_copy.wav", *audio))
	{
		printf("done!\n");
	}
	
  	FreeWAV(audio);
  
	return 0;
}