| /* |
| Simple DirectMedia Layer |
| Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org> |
| |
| This software is provided 'as-is', without any express or implied |
| warranty. In no event will the authors be held liable for any damages |
| arising from the use of this software. |
| |
| Permission is granted to anyone to use this software for any purpose, |
| including commercial applications, and to alter it and redistribute it |
| freely, subject to the following restrictions: |
| |
| 1. The origin of this software must not be misrepresented; you must not |
| claim that you wrote the original software. If you use this software |
| in a product, an acknowledgment in the product documentation would be |
| appreciated but is not required. |
| 2. Altered source versions must be plainly marked as such, and must not be |
| misrepresented as being the original software. |
| 3. This notice may not be removed or altered from any source distribution. |
| */ |
| |
| /** |
| * \file SDL_test_random.h |
| * |
| * Include file for SDL test framework. |
| * |
| * This code is a part of the SDL2_test library, not the main SDL library. |
| */ |
| |
| /* |
| |
| A "32-bit Multiply with carry random number generator. Very fast. |
| Includes a list of recommended multipliers. |
| |
| multiply-with-carry generator: x(n) = a*x(n-1) + carry mod 2^32. |
| period: (a*2^31)-1 |
| |
| */ |
| |
| #ifndef SDL_test_random_h_ |
| #define SDL_test_random_h_ |
| |
| #include "begin_code.h" |
| /* Set up for C function definitions, even when using C++ */ |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* --- Definitions */ |
| |
| /* |
| * Macros that return a random number in a specific format. |
| */ |
| #define SDLTest_RandomInt(c) ((int)SDLTest_Random(c)) |
| |
| /* |
| * Context structure for the random number generator state. |
| */ |
| typedef struct { |
| unsigned int a; |
| unsigned int x; |
| unsigned int c; |
| unsigned int ah; |
| unsigned int al; |
| } SDLTest_RandomContext; |
| |
| |
| /* --- Function prototypes */ |
| |
| /** |
| * \brief Initialize random number generator with two integers. |
| * |
| * Note: The random sequence of numbers returned by ...Random() is the |
| * same for the same two integers and has a period of 2^31. |
| * |
| * \param rndContext pointer to context structure |
| * \param xi integer that defines the random sequence |
| * \param ci integer that defines the random sequence |
| * |
| */ |
| void SDLTest_RandomInit(SDLTest_RandomContext * rndContext, unsigned int xi, |
| unsigned int ci); |
| |
| /** |
| * \brief Initialize random number generator based on current system time. |
| * |
| * \param rndContext pointer to context structure |
| * |
| */ |
| void SDLTest_RandomInitTime(SDLTest_RandomContext *rndContext); |
| |
| |
| /** |
| * \brief Initialize random number generator based on current system time. |
| * |
| * Note: ...RandomInit() or ...RandomInitTime() must have been called |
| * before using this function. |
| * |
| * \param rndContext pointer to context structure |
| * |
| * \returns A random number (32bit unsigned integer) |
| * |
| */ |
| unsigned int SDLTest_Random(SDLTest_RandomContext *rndContext); |
| |
| |
| /* Ends C function definitions when using C++ */ |
| #ifdef __cplusplus |
| } |
| #endif |
| #include "close_code.h" |
| |
| #endif /* SDL_test_random_h_ */ |
| |
| /* vi: set ts=4 sw=4 expandtab: */ |