Imported to git.

1 files changed, 69 insertions, 0 deletions

diff --git a/src/liblzma/common/vli_decoder.c b/src/liblzma/common/vli_decoder.c
new file mode 100644
index 00000000..2b89c1a7
--- /dev/null
+++ b/src/liblzma/common/vli_decoder.c
@@ -0,0 +1,69 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       vli_decoder.c
+/// \brief      Decodes variable-length integers
+//
+//  Copyright (C) 2007 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_vli_decode(lzma_vli *restrict vli, size_t *restrict vli_pos,
+		const uint8_t *restrict in, size_t *restrict in_pos,
+		size_t in_size)
+{
+	if (*vli > LZMA_VLI_VALUE_MAX || *vli_pos >= 9
+			|| (*vli >> (7 * *vli_pos)) != 0)
+		return LZMA_PROG_ERROR;
+
+	if (*in_pos >= in_size)
+		return LZMA_BUF_ERROR;
+
+	if (*vli_pos == 0) {
+		*vli_pos = 1;
+
+		if (in[*in_pos] <= 0x7F) {
+			// Single-byte integer
+			*vli = in[*in_pos];
+			++*in_pos;
+			return LZMA_STREAM_END;
+		}
+
+		*vli = in[*in_pos] & 0x7F;
+		++*in_pos;
+	}
+
+	while (*in_pos < in_size) {
+		// Read in the next byte.
+		*vli |= (lzma_vli)(in[*in_pos] & 0x7F) << (*vli_pos * 7);
+		++*vli_pos;
+
+		// Check if this is the last byte of a multibyte integer.
+		if (in[*in_pos] & 0x80) {
+			++*in_pos;
+			return LZMA_STREAM_END;
+		}
+
+		// Limit variable-length representation to nine bytes.
+		if (*vli_pos == 9)
+			return LZMA_DATA_ERROR;
+
+		// Increment input position only when the byte was accepted.
+		++*in_pos;
+	}
+
+	return LZMA_OK;
+}