Add an unpatched version of xz, XZ Utils, to /trunk/deps/third_party

xz/src/liblzma/common/stream_flags_encoder.c

+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file       stream_flags_encoder.c
+/// \brief      Encodes Stream Header and Stream Footer for .xz files
+//
+//  Author:     Lasse Collin
+//
+//  This file has been put into the public domain.
+//  You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include "stream_flags_common.h"
+
+
+static bool
+stream_flags_encode(const lzma_stream_flags *options, uint8_t *out)
+{
+        if ((unsigned int)(options->check) > LZMA_CHECK_ID_MAX)
+                return true;
+
+        out[0] = 0x00;
+        out[1] = options->check;
+
+        return false;
+}
+
+
+extern LZMA_API(lzma_ret)
+lzma_stream_header_encode(const lzma_stream_flags *options, uint8_t *out)
+{
+        assert(sizeof(lzma_header_magic) + LZMA_STREAM_FLAGS_SIZE
+                        + 4 == LZMA_STREAM_HEADER_SIZE);
+
+        if (options->version != 0)
+                return LZMA_OPTIONS_ERROR;
+
+        // Magic
+        memcpy(out, lzma_header_magic, sizeof(lzma_header_magic));
+
+        // Stream Flags
+        if (stream_flags_encode(options, out + sizeof(lzma_header_magic)))
+                return LZMA_PROG_ERROR;
+
+        // CRC32 of the Stream Header
+        const uint32_t crc = lzma_crc32(out + sizeof(lzma_header_magic),
+                        LZMA_STREAM_FLAGS_SIZE, 0);
+
+        unaligned_write32le(out + sizeof(lzma_header_magic)
+                        + LZMA_STREAM_FLAGS_SIZE, crc);
+
+        return LZMA_OK;
+}
+
+
+extern LZMA_API(lzma_ret)
+lzma_stream_footer_encode(const lzma_stream_flags *options, uint8_t *out)
+{
+        assert(2 * 4 + LZMA_STREAM_FLAGS_SIZE + sizeof(lzma_footer_magic)
+                        == LZMA_STREAM_HEADER_SIZE);
+
+        if (options->version != 0)
+                return LZMA_OPTIONS_ERROR;
+
+        // Backward Size
+        if (!is_backward_size_valid(options))
+                return LZMA_PROG_ERROR;
+
+        unaligned_write32le(out + 4, options->backward_size / 4 - 1);
+
+        // Stream Flags
+        if (stream_flags_encode(options, out + 2 * 4))
+                return LZMA_PROG_ERROR;
+
+        // CRC32
+        const uint32_t crc = lzma_crc32(
+                        out + 4, 4 + LZMA_STREAM_FLAGS_SIZE, 0);
+
+        unaligned_write32le(out, crc);
+
+        // Magic
+        memcpy(out + 2 * 4 + LZMA_STREAM_FLAGS_SIZE,
+                        lzma_footer_magic, sizeof(lzma_footer_magic));
+
+        return LZMA_OK;
+}