#endif
#include "wimlib.h"
-#include "wimlib/compress.h"
-#include "wimlib/decompress.h"
+#include "wimlib/compress_common.h"
+#include "wimlib/decompressor_ops.h"
+#include "wimlib/decompress_common.h"
#include "wimlib/error.h"
#include "wimlib/lzms.h"
#include "wimlib/util.h"
u32 upcoming_lz_offset;
u32 upcoming_delta_power;
u32 upcoming_delta_offset;
+
+ /* Used for postprocessing */
+ s32 last_target_usages[65536];
};
/* A table that maps position slots to their base values. These are constants
/* Decode the series of literals and matches from the LZMS-compressed data.
* Returns 0 on success; nonzero if the compressed data is invalid. */
static int
-lzms_decode_items(const u8 *cdata, size_t clen, u8 *ubuf, size_t ulen)
+lzms_decode_items(const u8 *cdata, size_t clen, u8 *ubuf, size_t ulen,
+ struct lzms_decompressor *ctx)
{
- /* XXX: The context could be allocated on the heap. */
- struct lzms_decompressor ctx;
-
/* Initialize the LZMS decompressor. */
- lzms_init_decompressor(&ctx, cdata, clen, ubuf, ulen);
+ lzms_init_decompressor(ctx, cdata, clen, ubuf, ulen);
/* Decode the sequence of items. */
- while (ctx.out_next != ctx.out_end) {
- LZMS_DEBUG("Position %u", ctx.out_next - ctx.out_begin);
- if (lzms_decode_item(&ctx))
+ while (ctx->out_next != ctx->out_end) {
+ LZMS_DEBUG("Position %u", ctx->out_next - ctx->out_begin);
+ if (lzms_decode_item(ctx))
return -1;
}
return 0;
* actually needs to be done (or to plug in alternate filters, like in LZMA),
* and the corresponding preprocessing seems to be done unconditionally. */
static void
-lzms_postprocess_data(u8 *ubuf, s32 ulen)
+lzms_postprocess_data(u8 *ubuf, s32 ulen, s32 *last_target_usages)
{
/* Offset (from beginning of buffer) of the most recent reference to a
* seemingly valid target address. */
s32 closest_target_usage = -LZMS_X86_MAX_TRANSLATION_OFFSET - 1;
- /* Offset (from beginning of buffer) of the most recently used target
- * address beginning with two bytes equal to the array index.
- *
- * XXX: This array could be allocated on the heap. */
- s32 last_target_usages[65536];
+ /* Initialize the last_target_usages array. Each entry will contain the
+ * offset (from beginning of buffer) of the most recently used target
+ * address beginning with two bytes equal to the array index. */
for (s32 i = 0; i < 65536; i++)
last_target_usages[i] = -LZMS_X86_MAX_GOOD_TARGET_OFFSET - 1;
last_target_usages);
}
-/* API function documented in wimlib.h */
-WIMLIBAPI int
-wimlib_lzms_decompress(const void *cdata, unsigned clen,
- void *ubuf, unsigned ulen)
+static int
+lzms_decompress(const void *compressed_data, size_t compressed_size,
+ void *uncompressed_data, size_t uncompressed_size, void *_ctx)
{
+ struct lzms_decompressor *ctx = _ctx;
+
/* The range decoder requires that a minimum of 4 bytes of compressed
* data be initially available. */
- if (clen < 4) {
- LZMS_DEBUG("Compressed length too small (got %u, expected >= 4)",
- clen);
+ if (compressed_size < 4) {
+ LZMS_DEBUG("Compressed size too small (got %zu, expected >= 4)",
+ compressed_size);
return -1;
}
/* A LZMS-compressed data block should be evenly divisible into 16-bit
* integers. */
- if (clen % 2 != 0) {
- LZMS_DEBUG("Compressed length not divisible by 2 (got %u)", clen);
+ if (compressed_size % 2 != 0) {
+ LZMS_DEBUG("Compressed size not divisible by 2 (got %zu)",
+ compressed_size);
return -1;
}
/* Handle the trivial case where nothing needs to be decompressed.
* (Necessary because a window of size 0 does not have a valid position
* slot.) */
- if (ulen == 0)
+ if (uncompressed_size == 0)
return 0;
/* The x86 post-processor requires that the uncompressed length fit into
* a signed 32-bit integer. Also, the position slot table cannot be
* searched for a position of INT32_MAX or greater. */
- if (ulen >= INT32_MAX) {
+ if (uncompressed_size >= INT32_MAX) {
LZMS_DEBUG("Uncompressed length too large "
"(got %u, expected < INT32_MAX)", ulen);
return -1;
}
/* Decode the literals and matches. */
- if (lzms_decode_items(cdata, clen, ubuf, ulen))
+ if (lzms_decode_items(compressed_data, compressed_size,
+ uncompressed_data, uncompressed_size, ctx))
return -1;
/* Postprocess the data. */
- lzms_postprocess_data(ubuf, ulen);
+ lzms_postprocess_data(uncompressed_data, uncompressed_size,
+ ctx->last_target_usages);
LZMS_DEBUG("Decompression successful.");
return 0;
}
+
+static void
+lzms_free_decompressor(void *_ctx)
+{
+ struct lzms_decompressor *ctx = _ctx;
+
+ FREE(ctx);
+}
+
+static int
+lzms_create_decompressor(size_t max_block_size,
+ const struct wimlib_decompressor_params_header *params,
+ void **ctx_ret)
+{
+ struct lzms_decompressor *ctx;
+
+ ctx = MALLOC(sizeof(struct lzms_decompressor));
+ if (ctx == NULL)
+ return WIMLIB_ERR_NOMEM;
+
+ *ctx_ret = ctx;
+ return 0;
+}
+
+const struct decompressor_ops lzms_decompressor_ops = {
+ .create_decompressor = lzms_create_decompressor,
+ .decompress = lzms_decompress,
+ .free_decompressor = lzms_free_decompressor,
+};
git://wimlib.net / wimlib / blobdiff