7 files changed, 83 insertions, 1 deletions

diff --git a/src/liblzma/delta/Makefile.am b/src/liblzma/delta/Makefile.am
new file mode 100644
index 00000000..fc09f5b8
--- /dev/null
+++ b/src/liblzma/delta/Makefile.am
@@ -0,0 +1,34 @@
+##
+##  Copyright (C) 2008 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.
+##
+
+noinst_LTLIBRARIES = libdelta.la
+libdelta_la_CPPFLAGS = \
+	-I@top_srcdir@/src/liblzma/api \
+	-I@top_srcdir@/src/liblzma/common
+
+libdelta_la_SOURCES = \
+	delta_common.c \
+	delta_common.h
+
+if COND_ENCODER_DELTA
+libdelta_la_SOURCES += \
+	delta_encoder.c \
+	delta_encoder.h
+endif
+
+if COND_DECODER_DELTA
+libdelta_la_SOURCES += \
+	delta_decoder.c \
+	delta_decoder.h
+endif
diff --git a/src/liblzma/common/delta_common.c b/src/liblzma/delta/delta_common.c
index acd31e14..d40e0c7f 100644
--- a/src/liblzma/common/delta_common.c
+++ b/src/liblzma/delta/delta_common.c
@@ -23,7 +23,7 @@
 static void
 delta_coder_end(lzma_coder *coder, lzma_allocator *allocator)
 {
-	lzma_next_coder_end(&coder->next, allocator);
+	lzma_next_end(&coder->next, allocator);
 	lzma_free(coder, allocator);
 	return;
 }
diff --git a/src/liblzma/common/delta_common.h b/src/liblzma/delta/delta_common.h
index 1d58899d..1d58899d 100644
--- a/src/liblzma/common/delta_common.h
+++ b/src/liblzma/delta/delta_common.h
diff --git a/src/liblzma/common/delta_decoder.c b/src/liblzma/delta/delta_decoder.c
index 8f5a4cbf..ee22ba02 100644
--- a/src/liblzma/common/delta_decoder.c
+++ b/src/liblzma/delta/delta_decoder.c
@@ -59,3 +59,24 @@ lzma_delta_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 {
 	return lzma_delta_coder_init(next, allocator, filters, &delta_decode);
 }
+
+
+extern lzma_ret
+lzma_delta_props_decode(void **options, lzma_allocator *allocator,
+		const uint8_t *props, size_t props_size)
+{
+	if (props_size != 1)
+		return LZMA_HEADER_ERROR;
+
+	lzma_options_delta *opt
+			= lzma_alloc(sizeof(lzma_options_delta), allocator);
+	if (opt == NULL)
+		return LZMA_MEM_ERROR;
+
+	opt->type = LZMA_DELTA_TYPE_BYTE;
+	opt->distance = props[0] + 1;
+
+	*options = opt;
+
+	return LZMA_OK;
+}
diff --git a/src/liblzma/common/delta_decoder.h b/src/liblzma/delta/delta_decoder.h
index bef9f58a..84852bf3 100644
--- a/src/liblzma/common/delta_decoder.h
+++ b/src/liblzma/delta/delta_decoder.h
@@ -25,4 +25,8 @@
 extern lzma_ret lzma_delta_decoder_init(lzma_next_coder *next,
 		lzma_allocator *allocator, const lzma_filter_info *filters);
 
+extern lzma_ret lzma_delta_props_decode(
+		void **options, lzma_allocator *allocator,
+		const uint8_t *props, size_t props_size);
+
 #endif
diff --git a/src/liblzma/common/delta_encoder.c b/src/liblzma/delta/delta_encoder.c
index a8bb9341..d8f40287 100644
--- a/src/liblzma/common/delta_encoder.c
+++ b/src/liblzma/delta/delta_encoder.c
@@ -96,3 +96,24 @@ lzma_delta_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
 {
 	return lzma_delta_coder_init(next, allocator, filters, &delta_encode);
 }
+
+
+extern lzma_ret
+lzma_delta_props_encode(const void *options, uint8_t *out)
+{
+	if (options == NULL)
+		return LZMA_PROG_ERROR;
+
+	const lzma_options_delta *opt = options;
+
+	// It's possible that newer liblzma versions will support larger
+	// distance values.
+	if (opt->type != LZMA_DELTA_TYPE_BYTE
+			|| opt->distance < LZMA_DELTA_DISTANCE_MIN
+			|| opt->distance > LZMA_DELTA_DISTANCE_MAX)
+		return LZMA_HEADER_ERROR;
+
+	out[0] = opt->distance - LZMA_DELTA_DISTANCE_MIN;
+
+	return LZMA_OK;
+}
diff --git a/src/liblzma/common/delta_encoder.h b/src/liblzma/delta/delta_encoder.h
index c669458d..b8b29c61 100644
--- a/src/liblzma/common/delta_encoder.h
+++ b/src/liblzma/delta/delta_encoder.h
@@ -25,4 +25,6 @@
 extern lzma_ret lzma_delta_encoder_init(lzma_next_coder *next,
 		lzma_allocator *allocator, const lzma_filter_info *filters);
 
+extern lzma_ret lzma_delta_props_encode(const void *options, uint8_t *out);
+
 #endif