#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#include <sys/mman.h>

#include "sha256.h"

#include "lzma.h"

/* TODO pass in the outbuf ? */
/* or wrap lzma_stream_buffer_bound */
void *compresslzma(void *buf, size_t bufsize, size_t *len) {
	/* xz compress it */
	size_t outsize;
	void *outbuf;
	size_t outlen = 0;
	int err = LZMA_OK;

	outsize = lzma_stream_buffer_bound(bufsize);
	outbuf = malloc(outsize);
	if (!outbuf) {
		*len = 0;
		fprintf(stderr, "failed to malloc compression buffer\n");
		return NULL;
	}
	/* TODO adjust encoding level for size */
	switch (err = lzma_easy_buffer_encode(6, LZMA_CHECK_CRC64, NULL,
			buf, bufsize,
			outbuf, &outlen, outsize
			)) {
		case LZMA_OK: break;
		case LZMA_OPTIONS_ERROR: fprintf(stderr, "lzma options error\n");
		default: fprintf(stderr, "lzma error %d\n", err);
		return NULL;
			 break;
	}
	*len = outlen;
	return outbuf;
}