1 files changed, 172 insertions, 0 deletions
diff --git a/lib/sqfs/src/comp/zstd.c b/lib/sqfs/src/comp/zstd.c
new file mode 100644
index 0000000..a6d7975
--- /dev/null
+++ b/lib/sqfs/src/comp/zstd.c
@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * zstd.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <zstd.h>
+#include <zstd_errors.h>
+
+#include "internal.h"
+
+typedef struct {
+	sqfs_compressor_t base;
+	size_t block_size;
+	ZSTD_CCtx *zctx;
+	int level;
+} zstd_compressor_t;
+
+typedef struct {
+	sqfs_u32 level;
+} zstd_options_t;
+
+static int zstd_write_options(sqfs_compressor_t *base, sqfs_file_t *file)
+{
+	zstd_compressor_t *zstd = (zstd_compressor_t *)base;
+	zstd_options_t opt;
+
+	if (zstd->level == SQFS_ZSTD_DEFAULT_LEVEL)
+		return 0;
+
+	opt.level = htole32(zstd->level);
+	return sqfs_generic_write_options(file, &opt, sizeof(opt));
+}
+
+static int zstd_read_options(sqfs_compressor_t *base, sqfs_file_t *file)
+{
+	zstd_options_t opt;
+	int ret;
+	(void)base;
+
+	ret = sqfs_generic_read_options(file, &opt, sizeof(opt));
+	if (ret)
+		return ret;
+
+	opt.level = le32toh(opt.level);
+	return 0;
+}
+
+static sqfs_s32 zstd_comp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
+				sqfs_u32 size, sqfs_u8 *out, sqfs_u32 outsize)
+{
+	zstd_compressor_t *zstd = (zstd_compressor_t *)base;
+	size_t ret;
+
+	if (size >= 0x7FFFFFFF)
+		return SQFS_ERROR_ARG_INVALID;
+
+	ret = ZSTD_compressCCtx(zstd->zctx, out, outsize, in, size,
+				zstd->level);
+
+	if (ZSTD_isError(ret)) {
+		if (ZSTD_getErrorCode(ret) == ZSTD_error_dstSize_tooSmall)
+			return 0;
+
+		return SQFS_ERROR_COMPRESSOR;
+	}
+
+	return ret < size ? ret : 0;
+}
+
+static sqfs_s32 zstd_uncomp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
+				  sqfs_u32 size, sqfs_u8 *out, sqfs_u32 outsize)
+{
+	size_t ret;
+	(void)base;
+
+	if (outsize >= 0x7FFFFFFF)
+		return SQFS_ERROR_ARG_INVALID;
+
+	ret = ZSTD_decompress(out, outsize, in, size);
+
+	if (ZSTD_isError(ret))
+		return SQFS_ERROR_COMPRESSOR;
+
+	return ret;
+}
+
+static void zstd_get_configuration(const sqfs_compressor_t *base,
+				   sqfs_compressor_config_t *cfg)
+{
+	const zstd_compressor_t *zstd = (const zstd_compressor_t *)base;
+
+	memset(cfg, 0, sizeof(*cfg));
+	cfg->id = SQFS_COMP_ZSTD;
+
+	cfg->block_size = zstd->block_size;
+	cfg->level = zstd->level;
+
+	if (base->do_block == zstd_uncomp_block)
+		cfg->flags |= SQFS_COMP_FLAG_UNCOMPRESS;
+}
+
+static sqfs_object_t *zstd_create_copy(const sqfs_object_t *cmp)
+{
+	zstd_compressor_t *zstd = malloc(sizeof(*zstd));
+
+	if (zstd == NULL)
+		return NULL;
+
+	memcpy(zstd, cmp, sizeof(*zstd));
+
+	zstd->zctx = ZSTD_createCCtx();
+
+	if (zstd->zctx == NULL) {
+		free(zstd);
+		return NULL;
+	}
+
+	return (sqfs_object_t *)zstd;
+}
+
+static void zstd_destroy(sqfs_object_t *base)
+{
+	zstd_compressor_t *zstd = (zstd_compressor_t *)base;
+
+	ZSTD_freeCCtx(zstd->zctx);
+	free(zstd);
+}
+
+int zstd_compressor_create(const sqfs_compressor_config_t *cfg,
+			   sqfs_compressor_t **out)
+{
+	zstd_compressor_t *zstd;
+	sqfs_compressor_t *base;
+
+	if (cfg->flags & ~SQFS_COMP_FLAG_GENERIC_ALL)
+		return SQFS_ERROR_UNSUPPORTED;
+
+	if (cfg->level < 1 || cfg->level > (unsigned int)ZSTD_maxCLevel())
+		return SQFS_ERROR_UNSUPPORTED;
+
+	zstd = calloc(1, sizeof(*zstd));
+	base = (sqfs_compressor_t *)zstd;
+	if (zstd == NULL)
+		return SQFS_ERROR_ALLOC;
+
+	sqfs_object_init(zstd, zstd_destroy, zstd_create_copy);
+
+	zstd->block_size = cfg->block_size;
+	zstd->level = cfg->level;
+	zstd->zctx = ZSTD_createCCtx();
+	if (zstd->zctx == NULL) {
+		free(zstd);
+		return SQFS_ERROR_COMPRESSOR;
+	}
+
+	base->get_configuration = zstd_get_configuration;
+	base->do_block = cfg->flags & SQFS_COMP_FLAG_UNCOMPRESS ?
+		zstd_uncomp_block : zstd_comp_block;
+	base->write_options = zstd_write_options;
+	base->read_options = zstd_read_options;
+
+	*out = base;
+	return 0;
+}