liblzma: Refactor to use lzma_filters_free().

lzma_filters_free() sets the options to NULL and ids to
LZMA_VLI_UNKNOWN so there is no need to do it by caller;
the filter arrays will always be left in a safe state.

Also use memcpy() instead of a loop to copy a filter chain
when it is known to be safe to copy LZMA_FILTERS_MAX + 1
(even if the elements past the terminator might be uninitialized).

2 files changed, 6 insertions, 21 deletions

diff --git a/src/liblzma/common/stream_encoder.c b/src/liblzma/common/stream_encoder.c
index b15229c3..ee920460 100644
--- a/src/liblzma/common/stream_encoder.c
+++ b/src/liblzma/common/stream_encoder.c
@@ -219,8 +219,7 @@ stream_encoder_end(void *coder_ptr, const lzma_allocator *allocator)
 	lzma_next_end(&coder->index_encoder, allocator);
 	lzma_index_end(coder->index, allocator);
 
-	for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
-		lzma_free(coder->filters[i].options, allocator);
+	lzma_filters_free(coder->filters, allocator);
 
 	lzma_free(coder, allocator);
 	return;
@@ -271,22 +270,15 @@ stream_encoder_update(void *coder_ptr, const lzma_allocator *allocator,
 	}
 
 	// Free the options of the old chain.
-	for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
-		lzma_free(coder->filters[i].options, allocator);
+	lzma_filters_free(coder->filters, allocator);
 
 	// Copy the new filter chain in place.
-	size_t j = 0;
-	do {
-		coder->filters[j].id = temp[j].id;
-		coder->filters[j].options = temp[j].options;
-	} while (temp[j++].id != LZMA_VLI_UNKNOWN);
+	memcpy(coder->filters, temp, sizeof(temp));
 
 	return LZMA_OK;
 
 error:
-	for (size_t i = 0; temp[i].id != LZMA_VLI_UNKNOWN; ++i)
-		lzma_free(temp[i].options, allocator);
-
+	lzma_filters_free(temp, allocator);
 	return ret;
 }
 
diff --git a/src/liblzma/common/stream_encoder_mt.c b/src/liblzma/common/stream_encoder_mt.c
index 3245aebd..2c6d4386 100644
--- a/src/liblzma/common/stream_encoder_mt.c
+++ b/src/liblzma/common/stream_encoder_mt.c
@@ -866,8 +866,7 @@ stream_encoder_mt_end(void *coder_ptr, const lzma_allocator *allocator)
 	threads_end(coder, allocator);
 	lzma_outq_end(&coder->outq, allocator);
 
-	for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
-		lzma_free(coder->filters[i].options, allocator);
+	lzma_filters_free(coder->filters, allocator);
 
 	lzma_next_end(&coder->index_encoder, allocator);
 	lzma_index_end(coder->index, allocator);
@@ -1068,13 +1067,7 @@ stream_encoder_mt_init(lzma_next_coder *next, const lzma_allocator *allocator,
 	coder->timeout = options->timeout;
 
 	// Free the old filter chain and copy the new one.
-	for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
-		lzma_free(coder->filters[i].options, allocator);
-
-	// Mark it as empty so that it is in a safe state in case
-	// lzma_filters_copy() fails.
-	coder->filters[0].id = LZMA_VLI_UNKNOWN;
-
+	lzma_filters_free(coder->filters, allocator);
 	return_if_error(lzma_filters_copy(
 			filters, coder->filters, allocator));