5 files changed, 66 insertions, 8 deletions

diff --git a/src/liblzma/lzma/lzma2_encoder.c b/src/liblzma/lzma/lzma2_encoder.c
index f1252c57..4b6b2311 100644
--- a/src/liblzma/lzma/lzma2_encoder.c
+++ b/src/liblzma/lzma/lzma2_encoder.c
@@ -341,7 +341,7 @@ lzma2_encoder_init(lzma_lz_encoder *lz, const lzma_allocator *allocator,
 
 	// Initialize LZMA encoder
 	return_if_error(lzma_lzma_encoder_create(&coder->lzma, allocator,
-			&coder->opt_cur, lz_options));
+			LZMA_FILTER_LZMA2, &coder->opt_cur, lz_options));
 
 	// Make sure that we will always have enough history available in
 	// case we need to use uncompressed chunks. They are used when the
diff --git a/src/liblzma/lzma/lzma_decoder.c b/src/liblzma/lzma/lzma_decoder.c
index 550963d1..26c148a9 100644
--- a/src/liblzma/lzma/lzma_decoder.c
+++ b/src/liblzma/lzma/lzma_decoder.c
@@ -1018,11 +1018,35 @@ lzma_decoder_init(lzma_lz_decoder *lz, const lzma_allocator *allocator,
 	if (!is_lclppb_valid(options))
 		return LZMA_PROG_ERROR;
 
+	lzma_vli uncomp_size = LZMA_VLI_UNKNOWN;
+	bool allow_eopm = true;
+
+	if (id == LZMA_FILTER_LZMA1EXT) {
+		const lzma_options_lzma *opt = options;
+
+		// Only one flag is supported.
+		if (opt->ext_flags & ~LZMA_LZMA1EXT_ALLOW_EOPM)
+			return LZMA_OPTIONS_ERROR;
+
+		// FIXME? Using lzma_vli instead of uint64_t is weird because
+		// this has nothing to do with .xz headers and variable-length
+		// integer encoding. On the other hand, using LZMA_VLI_UNKNOWN
+		// instead of UINT64_MAX is clearer when unknown size is
+		// meant. A problem with using lzma_vli is that now we
+		// allow > LZMA_VLI_MAX which is fine in this file but
+		// it's still confusing. Note that alone_decoder.c also
+		// allows > LZMA_VLI_MAX when setting uncompressed size.
+		uncomp_size = opt->ext_size_low
+				+ ((uint64_t)(opt->ext_size_high) << 32);
+		allow_eopm = (opt->ext_flags & LZMA_LZMA1EXT_ALLOW_EOPM) != 0
+				|| uncomp_size == LZMA_VLI_UNKNOWN;
+	}
+
 	return_if_error(lzma_lzma_decoder_create(
 			lz, allocator, options, lz_options));
 
 	lzma_decoder_reset(lz->coder, options);
-	lzma_decoder_uncompressed(lz->coder, LZMA_VLI_UNKNOWN, true);
+	lzma_decoder_uncompressed(lz->coder, uncomp_size, allow_eopm);
 
 	return LZMA_OK;
 }
diff --git a/src/liblzma/lzma/lzma_encoder.c b/src/liblzma/lzma/lzma_encoder.c
index e2dbbc03..dc62f44f 100644
--- a/src/liblzma/lzma/lzma_encoder.c
+++ b/src/liblzma/lzma/lzma_encoder.c
@@ -416,7 +416,7 @@ lzma_lzma_encode(lzma_lzma1_encoder *restrict coder, lzma_mf *restrict mf,
 	//
 	// Plain LZMA streams without EOPM aren't supported except when
 	// output size limiting is enabled.
-	if (limit == UINT32_MAX && coder->out_limit == 0)
+	if (coder->use_eopm)
 		encode_eopm(coder, (uint32_t)(coder->uncomp_size));
 
 	// Flush the remaining bytes from the range encoder.
@@ -462,6 +462,7 @@ lzma_lzma_set_out_limit(
 	lzma_lzma1_encoder *coder = coder_ptr;
 	coder->out_limit = out_limit;
 	coder->uncomp_size_ptr = uncomp_size;
+	coder->use_eopm = false;
 	return LZMA_OK;
 }
 
@@ -599,10 +600,13 @@ lzma_lzma_encoder_reset(lzma_lzma1_encoder *coder,
 
 
 extern lzma_ret
-lzma_lzma_encoder_create(void **coder_ptr,
-		const lzma_allocator *allocator,
-		const lzma_options_lzma *options, lzma_lz_options *lz_options)
+lzma_lzma_encoder_create(void **coder_ptr, const lzma_allocator *allocator,
+		lzma_vli id, const lzma_options_lzma *options,
+		lzma_lz_options *lz_options)
 {
+	assert(id == LZMA_FILTER_LZMA1 || id == LZMA_FILTER_LZMA1EXT
+			|| id == LZMA_FILTER_LZMA2);
+
 	// Allocate lzma_lzma1_encoder if it wasn't already allocated.
 	if (*coder_ptr == NULL) {
 		*coder_ptr = lzma_alloc(sizeof(lzma_lzma1_encoder), allocator);
@@ -672,6 +676,32 @@ lzma_lzma_encoder_create(void **coder_ptr,
 	// Output size limitting is disabled by default.
 	coder->out_limit = 0;
 
+	// Determine if end marker is wanted:
+	//   - It is never used with LZMA2.
+	//   - It is always used with LZMA_FILTER_LZMA1 (unless
+	//     lzma_lzma_set_out_limit() is called later).
+	//   - LZMA_FILTER_LZMA1EXT has a flag for it in the options.
+	coder->use_eopm = (id == LZMA_FILTER_LZMA1);
+	if (id == LZMA_FILTER_LZMA1EXT) {
+		// Check if unsupported flags are present.
+		if (options->ext_flags & ~LZMA_LZMA1EXT_ALLOW_EOPM)
+			return LZMA_OPTIONS_ERROR;
+
+		coder->use_eopm = (options->ext_flags
+				& LZMA_LZMA1EXT_ALLOW_EOPM) != 0;
+
+		// TODO? As long as there are no filters that change the size
+		// of the data, it is enough to look at lzma_stream.total_in
+		// after encoding has been finished to know the uncompressed
+		// size of the LZMA1 stream. But in the future there could be
+		// filters that change the size of the data and then total_in
+		// doesn't work as the LZMA1 stream size might be different
+		// due to another filter in the chain. The problem is simple
+		// to solve: Add another flag to ext_flags and then set
+		// coder->uncomp_size_ptr to the address stored in
+		// lzma_options_lzma.reserved_ptr2 (or _ptr1).
+	}
+
 	set_lz_options(lz_options, options);
 
 	return lzma_lzma_encoder_reset(coder, options);
@@ -685,7 +715,7 @@ lzma_encoder_init(lzma_lz_encoder *lz, const lzma_allocator *allocator,
 	lz->code = &lzma_encode;
 	lz->set_out_limit = &lzma_lzma_set_out_limit;
 	return lzma_lzma_encoder_create(
-			&lz->coder, allocator, options, lz_options);
+			&lz->coder, allocator, id, options, lz_options);
 }
 
 
diff --git a/src/liblzma/lzma/lzma_encoder.h b/src/liblzma/lzma/lzma_encoder.h
index 6cfdf228..84d8c916 100644
--- a/src/liblzma/lzma/lzma_encoder.h
+++ b/src/liblzma/lzma/lzma_encoder.h
@@ -40,7 +40,8 @@ extern bool lzma_lzma_lclppb_encode(
 /// Initializes raw LZMA encoder; this is used by LZMA2.
 extern lzma_ret lzma_lzma_encoder_create(
 		void **coder_ptr, const lzma_allocator *allocator,
-		const lzma_options_lzma *options, lzma_lz_options *lz_options);
+		lzma_vli id, const lzma_options_lzma *options,
+		lzma_lz_options *lz_options);
 
 
 /// Resets an already initialized LZMA encoder; this is used by LZMA2.
diff --git a/src/liblzma/lzma/lzma_encoder_private.h b/src/liblzma/lzma/lzma_encoder_private.h
index 8960c52c..b228c577 100644
--- a/src/liblzma/lzma/lzma_encoder_private.h
+++ b/src/liblzma/lzma/lzma_encoder_private.h
@@ -111,6 +111,9 @@ struct lzma_lzma1_encoder_s {
 	/// have been written to the output buffer yet.
 	bool is_flushed;
 
+	/// True if end of payload marker will be written.
+	bool use_eopm;
+
 	uint32_t pos_mask;         ///< (1 << pos_bits) - 1
 	uint32_t literal_context_bits;
 	uint32_t literal_pos_mask;