Bunch of liblzma tweaks, including some API changes.

The API and ABI should now be very close to stable,
although the code behind it isn't yet.

1 files changed, 38 insertions, 38 deletions

diff --git a/src/liblzma/api/lzma/container.h b/src/liblzma/api/lzma/container.h
index 800f2129..ba2c4f8f 100644
--- a/src/liblzma/api/lzma/container.h
+++ b/src/liblzma/api/lzma/container.h
@@ -26,30 +26,42 @@
  ************/
 
 /**
- * \brief       Default compression level for easy encoder
+ * \brief       Default compression preset
  *
- * It's not straightforward to recommend a default level, because in some
+ * It's not straightforward to recommend a default preset, because in some
  * cases keeping the resource usage relatively low is more important that
  * getting the maximum compression ratio.
  */
-#define LZMA_EASY_LEVEL_DEFAULT 6
+#define LZMA_PRESET_DEFAULT     UINT32_C(6)
+
+
+/**
+ * \brief       Mask for preset level
+ *
+ * This is useful only if you need to extract the level from the preset
+ * variable. That should be rare.
+ */
+#define LZMA_PRESET_LEVEL_MASK  UINT32_C(0x1F)
 
 
 /*
- * Flags for easy encoder
+ * Preset flags
  *
  * Currently only one flag is defined.
  */
 
 /**
- * Use significantly slower compression to get marginally better compression
- * ratio. This doesn't affect the memory requirements of the encoder or
- * decoder. This flag is useful when you don't mind wasting time to get as
- * small result as possible.
+ * \brief       Extreme compression preset
+ *
+ * This flag modifies the preset to make the encoding significantly slower
+ * while improving the compression ratio only marginally. This is useful
+ * when you don't mind wasting time to get as small result as possible.
  *
- * FIXME: Not implemented yet.
+ * This flag doesn't affect the memory usage requirements of the decoder (at
+ * least not significantly). The memory usage of the encoder may be increased
+ * a little but only at the lowest preset levels (0-4 or so).
  */
-#define LZMA_EASY_EXTREME       UINT32_C(0x01)
+#define LZMA_PRESET_EXTREME       (UINT32_C(1) << 31)
 
 
 /**
@@ -57,12 +69,9 @@
  *
  * This function is a wrapper for lzma_raw_encoder_memusage().
  *
- * \param       level   Compression level
- * \param       flags   Easy encoder flags (usually zero). This parameter is
- *                      needed, because in future some flags may affect the
- *                      memory requirements.
+ * \param       preset  Compression preset (level and possible flags)
  */
-extern uint64_t lzma_easy_encoder_memusage(uint32_t level, uint32_t flags)
+extern uint64_t lzma_easy_encoder_memusage(uint32_t preset)
 		lzma_attr_pure;
 
 
@@ -71,12 +80,9 @@ extern uint64_t lzma_easy_encoder_memusage(uint32_t level, uint32_t flags)
  *
  * This function is a wrapper for lzma_raw_decoder_memusage().
  *
- * \param       level   Compression level
- * \param       flags   Easy encoder flags (usually zero). This parameter is
- *                      needed, because in future some flags may affect the
- *                      memory requirements.
+ * \param       preset  Compression preset (level and possible flags)
  */
-extern uint64_t lzma_easy_decoder_memusage(uint32_t level, uint32_t flags)
+extern uint64_t lzma_easy_decoder_memusage(uint32_t preset)
 		lzma_attr_pure;
 
 
@@ -88,14 +94,12 @@ extern uint64_t lzma_easy_decoder_memusage(uint32_t level, uint32_t flags)
  *
  * \param       strm    Pointer to lzma_stream that is at least initialized
  *                      with LZMA_STREAM_INIT.
- * \param       level   Compression level to use. This selects a set of
- *                      compression settings from a list of compression
- *                      presets. Currently levels from 1 to 9 are defined,
- *                      which match the options -1 .. -9 of the xz command
- *                      line tool.
- * \param       flags   Flags that can finetune the compression preset.
- *                      In most cases, no flags are wanted, and this
- *                      parameter is zero.
+ * \param       preset  Compression preset to use. A preset consist of level
+ *                      number and zero or more flags. Usually flags aren't
+ *                      used, so preset is simply a number [0, 9] which match
+ *                      the options -0 .. -9 of the xz command line tool.
+ *                      Additional flags can be be set using bitwise-or with
+ *                      the preset level number, e.g. 6 | LZMA_PRESET_EXTREME.
  * \param       check   Integrity check type to use. See check.h for available
  *                      checks. If you are unsure, use LZMA_CHECK_CRC32.
  *
@@ -115,8 +119,8 @@ extern uint64_t lzma_easy_decoder_memusage(uint32_t level, uint32_t flags)
  * LZMA_RUN, LZMA_SYNC_FLUSH, LZMA_FULL_FLUSH, and LZMA_FINISH. In future,
  * there may be compression levels or flags that don't support LZMA_SYNC_FLUSH.
  */
-extern lzma_ret lzma_easy_encoder(lzma_stream *strm,
-		uint32_t level, uint32_t flags, lzma_check check)
+extern lzma_ret lzma_easy_encoder(
+		lzma_stream *strm, uint32_t preset, lzma_check check)
 		lzma_attr_warn_unused_result;
 
 
@@ -125,10 +129,8 @@ extern lzma_ret lzma_easy_encoder(lzma_stream *strm,
  *
  * \param       strm    Pointer to properly prepared lzma_stream
  * \param       filters Array of filters. This must be terminated with
- *                      filters[n].id = LZMA_VLI_UNKNOWN. There must
- *                      be 1-4 filters, but there are restrictions on how
- *                      multiple filters can be combined. FIXME Tell where
- *                      to find more information.
+ *                      filters[n].id = LZMA_VLI_UNKNOWN. See filter.h for
+ *                      more information.
  * \param       check   Type of the integrity check to calculate from
  *                      uncompressed data.
  *
@@ -153,15 +155,13 @@ extern lzma_ret lzma_stream_encoder(lzma_stream *strm,
  * legacy LZMA tools such as LZMA Utils 4.32.x. Moving to the .xz format
  * is strongly recommended.
  *
- * FIXME: Dictionary size limit?
- *
  * The valid action values for lzma_code() are LZMA_RUN and LZMA_FINISH.
  * No kind of flushing is supported, because the file format doesn't make
  * it possible.
  *
  * \return      - LZMA_OK
  *              - LZMA_MEM_ERROR
- *              - LZMA_OPTIONS_ERROR // FIXME
+ *              - LZMA_OPTIONS_ERROR
  *              - LZMA_PROG_ERROR
  */
 extern lzma_ret lzma_alone_encoder(
@@ -252,7 +252,7 @@ extern lzma_ret lzma_auto_decoder(
 
 
 /**
- * \brief       Initializes decoder for .lzma file
+ * \brief       Initialize .lzma decoder (legacy file format)
  *
  * Valid `action' arguments to lzma_code() are LZMA_RUN and LZMA_FINISH.
  * There is no need to use LZMA_FINISH, but allowing it may simplify