From 15431d4fd8de67a03af4ee9cc8e774e1750e9da2 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Mon, 14 Sep 2020 20:25:10 +0200 Subject: Add zstd stream compressor implementation to libfstream Signed-off-by: David Oberhollenzer --- lib/fstream/uncompress/zstd.c | 79 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 lib/fstream/uncompress/zstd.c (limited to 'lib/fstream/uncompress/zstd.c') diff --git a/lib/fstream/uncompress/zstd.c b/lib/fstream/uncompress/zstd.c new file mode 100644 index 0000000..1838af5 --- /dev/null +++ b/lib/fstream/uncompress/zstd.c @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * zstd.c + * + * Copyright (C) 2019 David Oberhollenzer + */ +#include "../internal.h" + +#include + +typedef struct { + istream_comp_t base; + + ZSTD_DStream* strm; +} istream_zstd_t; + +static int precache(istream_t *base) +{ + istream_zstd_t *zstd = (istream_zstd_t *)base; + istream_t *wrapped = ((istream_comp_t *)base)->wrapped; + ZSTD_outBuffer out; + ZSTD_inBuffer in; + size_t ret; + + if (istream_precache(wrapped)) + return -1; + + memset(&in, 0, sizeof(in)); + memset(&out, 0, sizeof(out)); + + in.src = wrapped->buffer; + in.size = wrapped->buffer_used; + + out.dst = ((istream_comp_t *)base)->uncompressed + base->buffer_used; + out.size = BUFSZ - base->buffer_used; + + ret = ZSTD_decompressStream(zstd->strm, &out, &in); + + if (ZSTD_isError(ret)) { + fprintf(stderr, "%s: error in zstd decoder.\n", + wrapped->get_filename(wrapped)); + return -1; + } + + wrapped->buffer_offset = in.pos; + base->buffer_used += out.pos; + return 0; +} + +static void cleanup(istream_comp_t *base) +{ + istream_zstd_t *zstd = (istream_zstd_t *)base; + + ZSTD_freeDStream(zstd->strm); +} + +istream_comp_t *istream_zstd_create(const char *filename) +{ + istream_zstd_t *zstd = calloc(1, sizeof(*zstd)); + istream_comp_t *base = (istream_comp_t *)zstd; + + if (zstd == NULL) { + fprintf(stderr, "%s: creating zstd decoder: %s.\n", + filename, strerror(errno)); + return NULL; + } + + zstd->strm = ZSTD_createDStream(); + if (zstd->strm == NULL) { + fprintf(stderr, "%s: error creating zstd decoder.\n", + filename); + free(zstd); + return NULL; + } + + ((istream_t *)base)->precache = precache; + base->cleanup = cleanup; + return base; +} -- cgit v1.2.3