/*
* Copyright (C) 2019-2020 Red Hat, Inc. All rights reserved.
*
* Author: Fabio M. Di Nitto <fabbione@kronosnet.org>
*
* This software licensed under LGPL-2.0+
*/
#define KNET_MODULE
#include "config.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <zstd.h>
#include "logging.h"
#include "compress_model.h"
#ifdef ZSTD_CLEVEL_DEFAULT
#define KNET_COMPRESS_DEFAULT ZSTD_CLEVEL_DEFAULT /* zstd default compression level from zstd.h */
#else
#define KNET_COMPRESS_DEFAULT KNET_COMPRESS_UNKNOWN_DEFAULT
#endif
struct zstd_ctx {
ZSTD_CCtx* cctx;
ZSTD_DCtx* dctx;
};
static int zstd_is_init(
knet_handle_t knet_h,
int method_idx)
{
if (knet_h->compress_int_data[method_idx]) {
return 1;
}
return 0;
}
static void zstd_fini(
knet_handle_t knet_h,
int method_idx)
{
struct zstd_ctx *zstd_ctx = knet_h->compress_int_data[knet_h->compress_model];
if (zstd_ctx) {
if (zstd_ctx->cctx) {
ZSTD_freeCCtx(zstd_ctx->cctx);
}
if (zstd_ctx->dctx) {
ZSTD_freeDCtx(zstd_ctx->dctx);
}
free(knet_h->compress_int_data[method_idx]);
knet_h->compress_int_data[method_idx] = NULL;
}
return;
}
static int zstd_init(
knet_handle_t knet_h,
int method_idx)
{
struct zstd_ctx *zstd_ctx;
int err = 0;
if (!knet_h->compress_int_data[method_idx]) {
zstd_ctx = malloc(sizeof(struct zstd_ctx));
if (!zstd_ctx) {
errno = ENOMEM;
return -1;
}
memset(zstd_ctx, 0, sizeof(struct zstd_ctx));
knet_h->compress_int_data[method_idx] = zstd_ctx;
zstd_ctx->cctx = ZSTD_createCCtx();
if (!zstd_ctx->cctx) {
log_err(knet_h, KNET_SUB_ZSTDCOMP, "Unable to create compression context");
err = -1;
goto out_err;
}
zstd_ctx->dctx = ZSTD_createDCtx();
if (!zstd_ctx->dctx) {
log_err(knet_h, KNET_SUB_ZSTDCOMP, "Unable to create decompression context");
err = -1;
goto out_err;
}
}
out_err:
if (err) {
zstd_fini(knet_h, method_idx);
}
return err;
}
static int zstd_compress(
knet_handle_t knet_h,
const unsigned char *buf_in,
const ssize_t buf_in_len,
unsigned char *buf_out,
ssize_t *buf_out_len)
{
struct zstd_ctx *zstd_ctx = knet_h->compress_int_data[knet_h->compress_model];
size_t compress_size;
compress_size = ZSTD_compressCCtx(zstd_ctx->cctx,
buf_out, *buf_out_len,
buf_in, buf_in_len,
knet_h->compress_level);
if (ZSTD_isError(compress_size)) {
log_err(knet_h, KNET_SUB_ZSTDCOMP, "error compressing packet: %s", ZSTD_getErrorName(compress_size));
/*
* ZSTD has lots of internal errors that are not easy to map
* to standard errnos. Use a generic one for now
*/
errno = EINVAL;
return -1;
}
*buf_out_len = compress_size;
return 0;
}
static int zstd_decompress(
knet_handle_t knet_h,
const unsigned char *buf_in,
const ssize_t buf_in_len,
unsigned char *buf_out,
ssize_t *buf_out_len)
{
struct zstd_ctx *zstd_ctx = knet_h->compress_int_data[knet_h->compress_model];
size_t decompress_size;
decompress_size = ZSTD_decompressDCtx(zstd_ctx->dctx,
buf_out, *buf_out_len,
buf_in, buf_in_len);
if (ZSTD_isError(decompress_size)) {
log_err(knet_h, KNET_SUB_ZSTDCOMP, "error decompressing packet: %s", ZSTD_getErrorName(decompress_size));
/*
* ZSTD has lots of internal errors that are not easy to map
* to standard errnos. Use a generic one for now
*/
errno = EINVAL;
return -1;
}
*buf_out_len = decompress_size;
return 0;
}
static int zstd_get_default_level()
{
return KNET_COMPRESS_DEFAULT;
}
compress_ops_t compress_model = {
KNET_COMPRESS_MODEL_ABI,
zstd_is_init,
zstd_init,
zstd_fini,
NULL,
zstd_compress,
zstd_decompress,
zstd_get_default_level
};