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.

4 files changed, 28 insertions, 11 deletions

diff --git a/src/liblzma/lz/lz_decoder.c b/src/liblzma/lz/lz_decoder.c
index a400bde1..ae969d62 100644
--- a/src/liblzma/lz/lz_decoder.c
+++ b/src/liblzma/lz/lz_decoder.c
@@ -387,11 +387,11 @@ lzma_lz_decoder_reset(lzma_lz_decoder *lz, lzma_allocator *allocator,
 		bool (*process)(lzma_coder *restrict coder,
 			const uint8_t *restrict in, size_t *restrict in_pos,
 			size_t in_size, bool has_safe_buffer),
-		lzma_vli uncompressed_size,
 		size_t history_size, size_t match_max_len)
 {
-	// Set uncompressed size.
-	lz->uncompressed_size = uncompressed_size;
+	// Known uncompressed size is used only with LZMA_Alone files so we
+	// set it always to unknown by default.
+	lz->uncompressed_size = LZMA_VLI_VALUE_UNKNOWN;
 
 	// Limit the history size to roughly sane values. This is primarily
 	// to prevent integer overflows.
diff --git a/src/liblzma/lz/lz_decoder.h b/src/liblzma/lz/lz_decoder.h
index a8a585cd..1acf9831 100644
--- a/src/liblzma/lz/lz_decoder.h
+++ b/src/liblzma/lz/lz_decoder.h
@@ -31,6 +31,11 @@
 		: (lz).dict[(lz).pos - (distance) - 1 + (lz).end])
 
 
+/// Test if dictionary is empty.
+#define lz_is_empty(lz) \
+	((lz).pos == 0 && !(lz).is_full)
+
+
 #define LZMA_LZ_DECODER_INIT \
 	(lzma_lz_decoder){ .dict = NULL, .size = 0, .match_max_len = 0 }
 
@@ -109,7 +114,6 @@ extern lzma_ret lzma_lz_decoder_reset(lzma_lz_decoder *lz,
 			lzma_coder *restrict coder, const uint8_t *restrict in,
 			size_t *restrict in_pos, size_t in_size,
 			bool has_safe_buffer),
-		lzma_vli uncompressed_size,
 		size_t history_size, size_t match_max_len);
 
 extern lzma_ret lzma_lz_decode(lzma_coder *coder, lzma_allocator *allocator,
@@ -155,12 +159,12 @@ lzma_lz_out_repeat(lzma_lz_decoder *lz, size_t distance, size_t length)
 	// in which e.g. the data of the previously decoded file(s)
 	// would be leaked (or whatever happens to be in unused
 	// part of the dictionary buffer).
-	if (distance >= lz->pos && !lz->is_full)
+	if (unlikely(distance >= lz->pos && !lz->is_full))
 		return false;
 
 	// It also doesn't make sense to copy data farer than
 	// the dictionary size.
-	if (distance >= lz->requested_size)
+	if (unlikely(distance >= lz->requested_size))
 		return false;
 
 	// The caller must have checked these!
diff --git a/src/liblzma/lzma/lzma_decoder.c b/src/liblzma/lzma/lzma_decoder.c
index dfe83589..d4cefe0b 100644
--- a/src/liblzma/lzma/lzma_decoder.c
+++ b/src/liblzma/lzma/lzma_decoder.c
@@ -547,6 +547,9 @@ decode_real(lzma_coder *restrict coder, const uint8_t *restrict in,
 					// Note that rep0 is known to have a safe value, thus we
 					// don't need to check if we are wrapping the dictionary
 					// when it isn't full yet.
+					if (unlikely(lz_is_empty(coder->lz)))
+						return true;
+
 					coder->lz.dict[coder->lz.pos]
 							= lz_get_byte(coder->lz, rep0);
 					++coder->lz.pos;
@@ -698,7 +701,6 @@ lzma_lzma_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 	{
 		const lzma_ret ret = lzma_lz_decoder_reset(
 				&next->coder->lz, allocator, &decode_real,
-				filters[0].uncompressed_size,
 				options->dictionary_size, MATCH_MAX_LEN);
 		if (ret != LZMA_OK) {
 			lzma_literal_end(&next->coder->literal_coder,
@@ -785,6 +787,15 @@ lzma_lzma_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 }
 
 
+extern void
+lzma_lzma_decoder_uncompressed_size(
+		lzma_next_coder *next, lzma_vli uncompressed_size)
+{
+	next->coder->lz.uncompressed_size = uncompressed_size;
+	return;
+}
+
+
 extern bool
 lzma_lzma_decode_properties(lzma_options_lzma *options, uint8_t byte)
 {
diff --git a/src/liblzma/lzma/lzma_decoder.h b/src/liblzma/lzma/lzma_decoder.h
index 929c2bff..9d57c7e5 100644
--- a/src/liblzma/lzma/lzma_decoder.h
+++ b/src/liblzma/lzma/lzma_decoder.h
@@ -24,10 +24,15 @@
 #include "common.h"
 
 
-/// \brief      Allocates and initializes LZMA decoder
+/// Allocates and initializes LZMA decoder
 extern lzma_ret lzma_lzma_decoder_init(lzma_next_coder *next,
 		lzma_allocator *allocator, const lzma_filter_info *filters);
 
+/// Set known uncompressed size. This is a hack needed to support
+/// LZMA_Alone files that don't have EOPM.
+extern void lzma_lzma_decoder_uncompressed_size(
+		lzma_next_coder *next, lzma_vli uncompressed_size);
+
 /// \brief      Decodes the LZMA Properties byte (lc/lp/pb)
 ///
 /// \return     true if error occorred, false on success
@@ -35,7 +40,4 @@ extern lzma_ret lzma_lzma_decoder_init(lzma_next_coder *next,
 extern bool lzma_lzma_decode_properties(
 		lzma_options_lzma *options, uint8_t byte);
 
-// There is no public lzma_lzma_encode() because lzma_lz_encode() works
-// as a wrapper for it.
-
 #endif