Fix a design error in liblzma API.

Originally the idea was that using LZMA_FULL_FLUSH
with Stream encoder would read the filter chain
from the same array that was used to intialize the
Stream encoder. Since most apps wouldn't use
LZMA_FULL_FLUSH, most apps wouldn't need to keep
the filter chain available after initializing the
Stream encoder. However, due to my mistake, it
actually required keeping the array always available.

Since setting the new filter chain via the array
used at initialization time is not a nice way to do
it for a couple of reasons, this commit ditches it
and introduces lzma_filters_update(). This new function
replaces also the "persistent" flag used by LZMA2
(and to-be-designed Subblock filter), which was also
an ugly thing to do.

Thanks to Alexey Tourbin for reminding me about the problem
that Stream encoder used to require keeping the filter
chain allocated.

1 files changed, 4 insertions, 59 deletions

diff --git a/src/liblzma/common/easy_encoder.c b/src/liblzma/common/easy_encoder.c
index 5e2641c9..d13ccd73 100644
--- a/src/liblzma/common/easy_encoder.c
+++ b/src/liblzma/common/easy_encoder.c
@@ -14,67 +14,12 @@
 #include "stream_encoder.h"
 
 
-struct lzma_coder_s {
-	lzma_next_coder stream_encoder;
-	lzma_options_easy opt_easy;
-};
-
-
-static lzma_ret
-easy_encode(lzma_coder *coder, lzma_allocator *allocator,
-		const uint8_t *restrict in, size_t *restrict in_pos,
-		size_t in_size, uint8_t *restrict out,
-		size_t *restrict out_pos, size_t out_size, lzma_action action)
-{
-	return coder->stream_encoder.code(
-			coder->stream_encoder.coder, allocator,
-			in, in_pos, in_size, out, out_pos, out_size, action);
-}
-
-
-static void
-easy_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
-{
-	lzma_next_end(&coder->stream_encoder, allocator);
-	lzma_free(coder, allocator);
-	return;
-}
-
-
-static lzma_ret
-easy_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
-		uint32_t preset, lzma_check check)
-{
-	lzma_next_coder_init(&easy_encoder_init, next, allocator);
-
-	if (next->coder == NULL) {
-		next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
-		if (next->coder == NULL)
-			return LZMA_MEM_ERROR;
-
-		next->code = &easy_encode;
-		next->end = &easy_encoder_end;
-
-		next->coder->stream_encoder = LZMA_NEXT_CODER_INIT;
-	}
-
-	if (lzma_easy_preset(&next->coder->opt_easy, preset))
-		return LZMA_OPTIONS_ERROR;
-
-	return lzma_stream_encoder_init(&next->coder->stream_encoder,
-			allocator, next->coder->opt_easy.filters, check);
-}
-
-
 extern LZMA_API(lzma_ret)
 lzma_easy_encoder(lzma_stream *strm, uint32_t preset, lzma_check check)
 {
-	lzma_next_strm_init(easy_encoder_init, strm, preset, check);
-
-	strm->internal->supported_actions[LZMA_RUN] = true;
-	strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
-	strm->internal->supported_actions[LZMA_FULL_FLUSH] = true;
-	strm->internal->supported_actions[LZMA_FINISH] = true;
+	lzma_options_easy opt_easy;
+	if (lzma_easy_preset(&opt_easy, preset))
+		return LZMA_OPTIONS_ERROR;
 
-	return LZMA_OK;
+	return lzma_stream_encoder(strm, opt_easy.filters, check);
 }