Update the code to mostly match the new simpler file format

specification. Simplify things by removing most of the
support for known uncompressed size in most places.
There are some miscellaneous changes here and there too.

The API of liblzma has got many changes and still some
more will be done soon. While most of the code has been
updated, some things are not fixed (the command line tool
will choke with invalid filter chain, if nothing else).

Subblock filter is somewhat broken for now. It will be
updated once the encoded format of the Subblock filter
has been decided.

1 files changed, 35 insertions, 21 deletions

diff --git a/src/liblzma/common/stream_flags_encoder.c b/src/liblzma/common/stream_flags_encoder.c
index 55468580..4efbb6f4 100644
--- a/src/liblzma/common/stream_flags_encoder.c
+++ b/src/liblzma/common/stream_flags_encoder.c
@@ -1,7 +1,7 @@
 ///////////////////////////////////////////////////////////////////////////////
 //
 /// \file       stream_flags_encoder.c
-/// \brief      Encodes Stream Header and Footer for .lzma files
+/// \brief      Encodes Stream Header and Stream Footer for .lzma files
 //
 //  Copyright (C) 2007 Lasse Collin
 //
@@ -21,55 +21,69 @@
 
 
 static bool
-stream_flags_encode(uint8_t *flags_byte, const lzma_stream_flags *options)
+stream_flags_encode(const lzma_stream_flags *options, uint8_t *out)
 {
-	// Check type
 	if ((unsigned int)(options->check) > LZMA_CHECK_ID_MAX)
 		return true;
 
-	*flags_byte = options->check;
-
-	// Usage of CRC32 in Block Headers
-	if (options->has_crc32)
-		*flags_byte |= 0x08;
-
-	// Single- or Multi-Block
-	if (options->is_multi)
-		*flags_byte |= 0x10;
+	out[0] = 0x00;
+	out[1] = options->check;
 
 	return false;
 }
 
 
 extern LZMA_API lzma_ret
-lzma_stream_header_encode(uint8_t *out, const lzma_stream_flags *options)
+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);
+
 	// Magic
 	memcpy(out, lzma_header_magic, sizeof(lzma_header_magic));
 
 	// Stream Flags
-	if (stream_flags_encode(out + sizeof(lzma_header_magic), options))
-		return LZMA_PROG_ERROR;;
+	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), 1, 0);
+	const uint32_t crc = lzma_crc32(out + sizeof(lzma_header_magic),
+			LZMA_STREAM_FLAGS_SIZE, 0);
 
-	for (size_t i = 0; i < 4; ++i)
-		out[sizeof(lzma_header_magic) + 1 + i] = crc >> (i * 8);
+	integer_write_32(out + sizeof(lzma_header_magic)
+			+ LZMA_STREAM_FLAGS_SIZE, crc);
 
 	return LZMA_OK;
 }
 
 
 extern LZMA_API lzma_ret
-lzma_stream_tail_encode(uint8_t *out, const lzma_stream_flags *options)
+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);
+
+	// Backward Size
+	if (options->backward_size < LZMA_BACKWARD_SIZE_MIN
+			|| options->backward_size > LZMA_BACKWARD_SIZE_MAX
+			|| (options->backward_size & 3))
+		return LZMA_PROG_ERROR;
+
+	integer_write_32(out + 4, options->backward_size / 4 - 1);
+
 	// Stream Flags
-	if (stream_flags_encode(out, options))
+	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);
+
+	integer_write_32(out, crc);
+
 	// Magic
-	memcpy(out + 1, lzma_footer_magic, sizeof(lzma_footer_magic));
+	memcpy(out + 2 * 4 + LZMA_STREAM_FLAGS_SIZE,
+			lzma_footer_magic, sizeof(lzma_footer_magic));
 
 	return LZMA_OK;
 }