Add wimlib_get_compressor_needed_memory()

[wimlib] / include / wimlib.h

diff --git a/include/wimlib.h b/include/wimlib.h
index 0fc5fb9fd4e77ce5e6d7443038dc59b40b7f9e7b..129a6c5a749a0e349b881fd0a5bd0ebe27b78870 100644 (file)
--- a/include/wimlib.h
+++ b/include/wimlib.h
@@ -4014,10 +4014,11 @@ struct wimlib_lzx_compressor_params {
 
                        uint32_t slow_reserved1 : 31;
 
-                       /** Matches with length (in bytes) longer than this
-                        * value are immediately taken without spending time on
-                        * minimum-cost measurements.  Suggested value: 32.  */
-                       uint32_t num_fast_bytes;
+                       /** Matches with length (in bytes) greater than or equal
+                        * to this value are immediately taken without spending
+                        * time on minimum-cost measurements.  Suggested value:
+                        * 32.  */
+                       uint32_t nice_match_length;
 
                        /** Number of passes to compute a match/literal sequence
                         * for each LZX block.  This is for an iterative
@@ -4060,6 +4061,42 @@ struct wimlib_lzx_compressor_params {
        } alg_params;
 };
 
+/** LZMS compression parameters that can optionally be passed to
+ * wimlib_create_compressor() with the compression type
+ * ::WIMLIB_COMPRESSION_TYPE_LZMS.  */
+struct wimlib_lzms_compressor_params {
+       /** hdr.size Must be set to the size of this structure, in bytes.  */
+       struct wimlib_compressor_params_header hdr;
+
+       /** Minimum match length to output.  This must be at least 2.  Suggested
+        * value: 2  */
+       uint32_t min_match_length;
+
+       /** Maximum match length to output.  This must be at least @p
+        * min_match_length.  Suggested value: @p UINT32_MAX.  */
+       uint32_t max_match_length;
+
+       /** Matches with length (in bytes) greater than or equal to this value
+        * are immediately taken without spending time on minimum-cost
+        * measurements.  The minimum of @p max_match_length and @p
+        * nice_match_length may not exceed 65536.  Suggested value: 32.  */
+       uint32_t nice_match_length;
+
+       /** Maximum depth to search for matches at each position.  Suggested
+        * value: 50.  */
+       uint32_t max_search_depth;
+
+       /** Maximum number of potentially good matches to consider at each
+        * position.  Suggested value: 3.  */
+       uint32_t max_matches_per_pos;
+
+       /** Length of the array for the near-optimal LZ parsing algorithm.  This
+        * must be at least 1.  Suggested value: 1024.  */
+       uint32_t optim_array_length;
+
+       uint64_t reserved2[4];
+};
+
 /** Opaque compressor handle.  */
 struct wimlib_compressor;
 
@@ -4081,6 +4118,8 @@ struct wimlib_decompressor;
  *
  * @retval ::WIMLIB_ERR_INVALID_COMPRESSION_TYPE
  *     @p ctype was not a supported compression type.
+ * @retval ::WIMLIB_ERR_INVALID_PARAM
+ *     @p params were invalid.
  * @retval ::WIMLIB_ERR_NOMEM
  *     Not enough memory to duplicate the parameters (perhaps @c params->size
  *     was invalid).
@@ -4089,6 +4128,18 @@ extern int
 wimlib_set_default_compressor_params(enum wimlib_compression_type ctype,
                                     const struct wimlib_compressor_params_header *params);
 
+/**
+ * Returns the approximate number of bytes needed to allocate a compressor with
+ * wimlib_create_compressor() for the specified compression type, block size,
+ * and parameters.  @p params may be @c NULL, in which case the current default
+ * parameters for @p ctype are used.  Returns 0 if the compression type or
+ * parameters are invalid.
+ */
+extern uint64_t
+wimlib_get_compressor_needed_memory(enum wimlib_compression_type ctype,
+                                   size_t max_block_size,
+                                   const struct wimlib_compressor_params_header *params);
+
 /**
  * Allocate a compressor for the specified compression type using the specified
  * parameters.