base.h

// SPDX-FileCopyrightText: 2023 Erin Catto
// SPDX-License-Identifier: MIT
 
#pragma once
 
#include <stdint.h>
 
// clang-format off
// 
// Shared library macros
#if defined( _MSC_VER ) && defined( box2d_EXPORTS )
    // build the Windows DLL
    #define BOX2D_EXPORT __declspec( dllexport )
#elif defined( _MSC_VER ) && defined( BOX2D_DLL )
    // using the Windows DLL
    #define BOX2D_EXPORT __declspec( dllimport )
#elif defined( box2d_EXPORTS )
    // building or using the Box2D shared library
    #define BOX2D_EXPORT __attribute__( ( visibility( "default" ) ) )
#else
    // static library
    #define BOX2D_EXPORT
#endif
 
// C++ macros
#ifdef __cplusplus
    #define B2_API extern "C" BOX2D_EXPORT
    #define B2_INLINE inline
    #define B2_LITERAL(T) T
    #define B2_ZERO_INIT {}
#else
    #define B2_API BOX2D_EXPORT
    #define B2_INLINE static inline
    #define B2_LITERAL(T) (T)
    #define B2_ZERO_INIT {0}
#endif
// clang-format on
 
typedef void* b2AllocFcn( unsigned int size, int alignment );
 
typedef void b2FreeFcn( void* mem );
 
typedef int b2AssertFcn( const char* condition, const char* fileName, int lineNumber );
 
B2_API void b2SetAllocator( b2AllocFcn* allocFcn, b2FreeFcn* freeFcn );
 
B2_API int b2GetByteCount( void );
 
B2_API void b2SetAssertFcn( b2AssertFcn* assertFcn );
 
typedef struct b2Version
{
    int major;
 
    int minor;
 
    int revision;
} b2Version;
 
B2_API b2Version b2GetVersion( void );
 
// Timer for profiling. This has platform specific code and may not work on every platform.
typedef struct b2Timer
{
#if defined( _WIN32 )
    int64_t start;
#elif defined( __linux__ ) || defined( __APPLE__ )
    unsigned long long start_sec;
    unsigned long long start_usec;
#else
    int32_t dummy;
#endif
} b2Timer;
 
B2_API b2Timer b2CreateTimer( void );
B2_API int64_t b2GetTicks( b2Timer* timer );
B2_API float b2GetMilliseconds( const b2Timer* timer );
B2_API float b2GetMillisecondsAndReset( b2Timer* timer );
B2_API void b2SleepMilliseconds( int milliseconds );
B2_API void b2Yield( void );
 
// Simple djb2 hash function for determinism testing
#define B2_HASH_INIT 5381
B2_API uint32_t b2Hash( uint32_t hash, const uint8_t* data, int count );