/* ******************************************************************
- hist : Histogram functions
- part of Finite State Entropy project
- Copyright (C) 2013-present, Yann Collet.
-
- BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are
- met:
-
- * Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above
- copyright notice, this list of conditions and the following disclaimer
- in the documentation and/or other materials provided with the
- distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
- You can contact the author at :
- - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
- - Public forum : https://groups.google.com/forum/#!forum/lz4c
+ * hist : Histogram functions
+ * part of Finite State Entropy project
+ * Copyright (c) 2013-2020, Yann Collet, Facebook, Inc.
+ *
+ * You can contact the author at :
+ * - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ * - Public forum : https://groups.google.com/forum/#!forum/lz4c
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
****************************************************************** */
/* --- dependencies --- */
/*! HIST_count():
* Provides the precise count of each byte within a table 'count'.
- * 'count' is a table of unsigned int, of minimum size (*maxSymbolValuePtr+1).
+ * 'count' is a table of unsigned int, of minimum size (*maxSymbolValuePtr+1).
* Updates *maxSymbolValuePtr with actual largest symbol value detected.
- * @return : count of the most frequent symbol (which isn't identified).
- * or an error code, which can be tested using HIST_isError().
- * note : if return == srcSize, there is only one symbol.
+ * @return : count of the most frequent symbol (which isn't identified).
+ * or an error code, which can be tested using HIST_isError().
+ * note : if return == srcSize, there is only one symbol.
*/
size_t HIST_count(unsigned* count, unsigned* maxSymbolValuePtr,
const void* src, size_t srcSize);
/* --- advanced histogram functions --- */
#define HIST_WKSP_SIZE_U32 1024
+#define HIST_WKSP_SIZE (HIST_WKSP_SIZE_U32 * sizeof(unsigned))
/** HIST_count_wksp() :
* Same as HIST_count(), but using an externally provided scratch buffer.
* Benefit is this function will use very little stack space.
- * `workSpace` must be a table of unsigned of size >= HIST_WKSP_SIZE_U32
+ * `workSpace` is a writable buffer which must be 4-bytes aligned,
+ * `workSpaceSize` must be >= HIST_WKSP_SIZE
*/
size_t HIST_count_wksp(unsigned* count, unsigned* maxSymbolValuePtr,
const void* src, size_t srcSize,
- unsigned* workSpace);
+ void* workSpace, size_t workSpaceSize);
/** HIST_countFast() :
* same as HIST_count(), but blindly trusts that all byte values within src are <= *maxSymbolValuePtr.
/** HIST_countFast_wksp() :
* Same as HIST_countFast(), but using an externally provided scratch buffer.
- * `workSpace` must be a table of unsigned of size >= HIST_WKSP_SIZE_U32
+ * `workSpace` is a writable buffer which must be 4-bytes aligned,
+ * `workSpaceSize` must be >= HIST_WKSP_SIZE
*/
size_t HIST_countFast_wksp(unsigned* count, unsigned* maxSymbolValuePtr,
const void* src, size_t srcSize,
- unsigned* workSpace);
+ void* workSpace, size_t workSpaceSize);
/*! HIST_count_simple() :
* Same as HIST_countFast(), this function is unsafe,