1 files changed, 73 insertions, 0 deletions
diff --git a/src/liblzma/common/block_util.c b/src/liblzma/common/block_util.c
new file mode 100644
index 00000000..6bffc2f1
--- /dev/null
+++ b/src/liblzma/common/block_util.c
@@ -0,0 +1,73 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       block_header.c
+/// \brief      Utility functions to handle lzma_options_block
+//
+//  Copyright (C) 2008 Lasse Collin
+//
+//  This library is free software; you can redistribute it and/or
+//  modify it under the terms of the GNU Lesser General Public
+//  License as published by the Free Software Foundation; either
+//  version 2.1 of the License, or (at your option) any later version.
+//
+//  This library is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+//  Lesser General Public License for more details.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "common.h"
+
+
+extern LZMA_API lzma_ret
+lzma_block_total_size_set(lzma_options_block *options, lzma_vli total_size)
+{
+	// Validate.
+	if (options->header_size < LZMA_BLOCK_HEADER_SIZE_MIN
+			|| options->header_size > LZMA_BLOCK_HEADER_SIZE_MAX
+			|| (options->header_size & 3)
+			|| (unsigned)(options->check) > LZMA_CHECK_ID_MAX
+			|| (total_size & 3))
+		return LZMA_PROG_ERROR;
+
+	const uint32_t container_size = options->header_size
+			+ lzma_check_sizes[options->check];
+
+	// Validate that Compressed Size will be greater than zero.
+	if (container_size <= total_size)
+		return LZMA_DATA_ERROR;
+
+	options->compressed_size = total_size - container_size;
+
+	return LZMA_OK;
+}
+
+
+extern LZMA_API lzma_vli
+lzma_block_total_size_get(const lzma_options_block *options)
+{
+	// Validate the values that we are interested in.
+	if (options->header_size < LZMA_BLOCK_HEADER_SIZE_MIN
+			|| options->header_size > LZMA_BLOCK_HEADER_SIZE_MAX
+			|| (options->header_size & 3)
+			|| (unsigned)(options->check) > LZMA_CHECK_ID_MAX)
+		return 0;
+
+	// If Compressed Size is unknown, return that we cannot know
+	// Total Size either.
+	if (options->compressed_size == LZMA_VLI_VALUE_UNKNOWN)
+		return LZMA_VLI_VALUE_UNKNOWN;
+
+	const lzma_vli total_size = options->compressed_size
+			+ options->header_size
+			+ lzma_check_sizes[options->check];
+
+	// Validate the calculated Total Size.
+	if (options->compressed_size > LZMA_VLI_VALUE_MAX
+			|| (options->compressed_size & 3)
+			|| total_size > LZMA_VLI_VALUE_MAX)
+		return 0;
+
+	return total_size;
+}