SDL/include/SDL3/SDL_stdinc.h

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2024 Sam Lantinga <[email protected]>

  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.
*/

/**
 * # CategoryStdinc
 *
 * This is a general header that includes C language support. It implements a
 * subset of the C runtime: these should all behave the same way as their C
 * runtime equivalents, but with an SDL_ prefix.
 */

#ifndef SDL_stdinc_h_
#define SDL_stdinc_h_

#include <SDL3/SDL_platform_defines.h>

#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#include <inttypes.h>
#endif
#include <stdarg.h>
#include <stdint.h>
#include <string.h>
#include <wchar.h>

#ifndef SDL_DISABLE_ALLOCA
# ifndef alloca
#  ifdef HAVE_ALLOCA_H
#   include <alloca.h>
#  elif defined(SDL_PLATFORM_NETBSD)
#   if defined(__STRICT_ANSI__)
#    define SDL_DISABLE_ALLOCA
#   else
#    include <stdlib.h>
#   endif
#  elif defined(__GNUC__)
#   define alloca __builtin_alloca
#  elif defined(_MSC_VER)
#   include <malloc.h>
#   define alloca _alloca
#  elif defined(__WATCOMC__)
#   include <malloc.h>
#  elif defined(__BORLANDC__)
#   include <malloc.h>
#  elif defined(__DMC__)
#   include <stdlib.h>
#  elif defined(SDL_PLATFORM_AIX)
# pragma alloca
#  elif defined(__MRC__)
void *alloca(unsigned);
#  else
void *alloca(size_t);
#  endif
# endif
#endif

#ifdef SIZE_MAX
# define SDL_SIZE_MAX SIZE_MAX
#else
# define SDL_SIZE_MAX ((size_t) -1)
#endif

/**
 * Check if the compiler supports a given builtin.
 * Supported by virtually all clang versions and recent gcc. Use this
 * instead of checking the clang version if possible.
 */
#ifdef __has_builtin
#define SDL_HAS_BUILTIN(x) __has_builtin(x)
#else
#define SDL_HAS_BUILTIN(x) 0
#endif

/**
 * The number of elements in an array.
 *
 * NOTE: This macro double-evaluates the argument, so you should never have
 * side effects in the parameter.
 *
 * \since This macro is available since SDL 3.0.0.
 */
#define SDL_arraysize(array) (sizeof(array)/sizeof(array[0]))

/**
 * Macro useful for building other macros with strings in them.
 *
 * For example:
 *
 * ```c
 * #define LOG_ERROR(X) OutputDebugString(SDL_STRINGIFY_ARG(__FUNCTION__) ": " X "\n")`
 * ```
 *
 * \since This macro is available since SDL 3.0.0.
 */
#define SDL_STRINGIFY_ARG(arg)  #arg

/**
 *  \name Cast operators
 *
 *  Use proper C++ casts when compiled as C++ to be compatible with the option
 *  -Wold-style-cast of GCC (and -Werror=old-style-cast in GCC 4.2 and above).
 */
/* @{ */
#ifdef __cplusplus
#define SDL_reinterpret_cast(type, expression) reinterpret_cast<type>(expression)
#define SDL_static_cast(type, expression) static_cast<type>(expression)
#define SDL_const_cast(type, expression) const_cast<type>(expression)
#else
#define SDL_reinterpret_cast(type, expression) ((type)(expression))
#define SDL_static_cast(type, expression) ((type)(expression))
#define SDL_const_cast(type, expression) ((type)(expression))
#endif
/* @} *//* Cast operators */

/* Define a four character code as a Uint32 */
#define SDL_FOURCC(A, B, C, D) \
    ((SDL_static_cast(Uint32, SDL_static_cast(Uint8, (A))) << 0) | \
     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (B))) << 8) | \
     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (C))) << 16) | \
     (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (D))) << 24))

#ifdef SDL_WIKI_DOCUMENTATION_SECTION

/**
 * Append the 64 bit integer suffix to a signed integer literal.
 *
 * This helps compilers that might believe a integer literal larger than
 * 0xFFFFFFFF is overflowing a 32-bit value. Use `SDL_SINT64_C(0xFFFFFFFF1)`
 * instead of `0xFFFFFFFF1` by itself.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_UINT64_C
 */
#define SDL_SINT64_C(c)  c ## LL  /* or whatever the current compiler uses. */

/**
 * Append the 64 bit integer suffix to an unsigned integer literal.
 *
 * This helps compilers that might believe a integer literal larger than
 * 0xFFFFFFFF is overflowing a 32-bit value. Use `SDL_UINT64_C(0xFFFFFFFF1)`
 * instead of `0xFFFFFFFF1` by itself.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_SINT64_C
 */
#define SDL_UINT64_C(c)  c ## ULL /* or whatever the current compiler uses. */

#elif defined(INT64_C)
#define SDL_SINT64_C(c)  INT64_C(c)
#define SDL_UINT64_C(c)  UINT64_C(c)
#elif defined(_MSC_VER)
#define SDL_SINT64_C(c)  c ## i64
#define SDL_UINT64_C(c)  c ## ui64
#elif defined(__LP64__) || defined(_LP64)
#define SDL_SINT64_C(c)  c ## L
#define SDL_UINT64_C(c)  c ## UL
#else
#define SDL_SINT64_C(c)  c ## LL
#define SDL_UINT64_C(c)  c ## ULL
#endif

/**
 *  \name Basic data types
 */
/* @{ */

/**
 * A boolean false.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_bool
 */
#define SDL_FALSE 0

/**
 * A boolean true.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_bool
 */
#define SDL_TRUE 1

/**
 * A boolean type: true or false.
 *
 * \since This datatype is available since SDL 3.0.0.
 *
 * \sa SDL_TRUE
 * \sa SDL_FALSE
 */
typedef int SDL_bool;

/**
 * A signed 8-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef int8_t Sint8;
#define SDL_MAX_SINT8   ((Sint8)0x7F)           /* 127 */
#define SDL_MIN_SINT8   ((Sint8)(~0x7F))        /* -128 */

/**
 * An unsigned 8-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef uint8_t Uint8;
#define SDL_MAX_UINT8   ((Uint8)0xFF)           /* 255 */
#define SDL_MIN_UINT8   ((Uint8)0x00)           /* 0 */

/**
 * A signed 16-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef int16_t Sint16;
#define SDL_MAX_SINT16  ((Sint16)0x7FFF)        /* 32767 */
#define SDL_MIN_SINT16  ((Sint16)(~0x7FFF))     /* -32768 */

/**
 * An unsigned 16-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef uint16_t Uint16;
#define SDL_MAX_UINT16  ((Uint16)0xFFFF)        /* 65535 */
#define SDL_MIN_UINT16  ((Uint16)0x0000)        /* 0 */

/**
 * A signed 32-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef int32_t Sint32;
#define SDL_MAX_SINT32  ((Sint32)0x7FFFFFFF)    /* 2147483647 */
#define SDL_MIN_SINT32  ((Sint32)(~0x7FFFFFFF)) /* -2147483648 */

/**
 * An unsigned 32-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 */
typedef uint32_t Uint32;
#define SDL_MAX_UINT32  ((Uint32)0xFFFFFFFFu)   /* 4294967295 */
#define SDL_MIN_UINT32  ((Uint32)0x00000000)    /* 0 */

/**
 * A signed 64-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_SINT64_C
 */
typedef int64_t Sint64;
#define SDL_MAX_SINT64  SDL_SINT64_C(0x7FFFFFFFFFFFFFFF)   /* 9223372036854775807 */
#define SDL_MIN_SINT64  ~SDL_SINT64_C(0x7FFFFFFFFFFFFFFF)  /* -9223372036854775808 */

/**
 * An unsigned 64-bit integer type.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_UINT64_C
 */
typedef uint64_t Uint64;
#define SDL_MAX_UINT64  SDL_UINT64_C(0xFFFFFFFFFFFFFFFF)   /* 18446744073709551615 */
#define SDL_MIN_UINT64  SDL_UINT64_C(0x0000000000000000)   /* 0 */

/**
 * SDL times are signed, 64-bit integers representing nanoseconds since the
 * Unix epoch (Jan 1, 1970).
 *
 * They can be converted between POSIX time_t values with SDL_NS_TO_SECONDS()
 * and SDL_SECONDS_TO_NS(), and between Windows FILETIME values with
 * SDL_TimeToWindows() and SDL_TimeFromWindows().
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_MAX_SINT64
 * \sa SDL_MIN_SINT64
 */
typedef Sint64 SDL_Time;
#define SDL_MAX_TIME SDL_MAX_SINT64
#define SDL_MIN_TIME SDL_MIN_SINT64

/* @} *//* Basic data types */

/**
 *  \name Floating-point constants
 */
/* @{ */

#ifdef FLT_EPSILON
#define SDL_FLT_EPSILON FLT_EPSILON
#else

/**
 * Epsilon constant, used for comparing floating-point numbers.
 *
 * Equals by default to platform-defined `FLT_EPSILON`, or
 * `1.1920928955078125e-07F` if that's not available.
 *
 * \since This macro is available since SDL 3.0.0.
 */
#define SDL_FLT_EPSILON 1.1920928955078125e-07F /* 0x0.000002p0 */
#endif

/* @} *//* Floating-point constants */

/* Make sure we have macros for printing width-based integers.
 * <stdint.h> should define these but this is not true all platforms.
 * (for example win32) */
#ifndef SDL_PRIs64
#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_GDK)
#define SDL_PRIs64 "I64d"
#elif defined(PRIs64)
#define SDL_PRIs64 PRIs64
#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
#define SDL_PRIs64 "ld"
#else
#define SDL_PRIs64 "lld"
#endif
#endif
#ifndef SDL_PRIu64
#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_GDK)
#define SDL_PRIu64 "I64u"
#elif defined(PRIu64)
#define SDL_PRIu64 PRIu64
#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
#define SDL_PRIu64 "lu"
#else
#define SDL_PRIu64 "llu"
#endif
#endif
#ifndef SDL_PRIx64
#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_GDK)
#define SDL_PRIx64 "I64x"
#elif defined(PRIx64)
#define SDL_PRIx64 PRIx64
#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
#define SDL_PRIx64 "lx"
#else
#define SDL_PRIx64 "llx"
#endif
#endif
#ifndef SDL_PRIX64
#if defined(SDL_PLATFORM_WIN32) || defined(SDL_PLATFORM_GDK)
#define SDL_PRIX64 "I64X"
#elif defined(PRIX64)
#define SDL_PRIX64 PRIX64
#elif defined(__LP64__) && !defined(SDL_PLATFORM_APPLE)
#define SDL_PRIX64 "lX"
#else
#define SDL_PRIX64 "llX"
#endif
#endif
#ifndef SDL_PRIs32
#ifdef PRId32
#define SDL_PRIs32 PRId32
#else
#define SDL_PRIs32 "d"
#endif
#endif
#ifndef SDL_PRIu32
#ifdef PRIu32
#define SDL_PRIu32 PRIu32
#else
#define SDL_PRIu32 "u"
#endif
#endif
#ifndef SDL_PRIx32
#ifdef PRIx32
#define SDL_PRIx32 PRIx32
#else
#define SDL_PRIx32 "x"
#endif
#endif
#ifndef SDL_PRIX32
#ifdef PRIX32
#define SDL_PRIX32 PRIX32
#else
#define SDL_PRIX32 "X"
#endif
#endif

/* Annotations to help code analysis tools */
#ifdef SDL_DISABLE_ANALYZE_MACROS
#define SDL_IN_BYTECAP(x)
#define SDL_INOUT_Z_CAP(x)
#define SDL_OUT_Z_CAP(x)
#define SDL_OUT_CAP(x)
#define SDL_OUT_BYTECAP(x)
#define SDL_OUT_Z_BYTECAP(x)
#define SDL_PRINTF_FORMAT_STRING
#define SDL_SCANF_FORMAT_STRING
#define SDL_PRINTF_VARARG_FUNC( fmtargnumber )
#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber )
#define SDL_SCANF_VARARG_FUNC( fmtargnumber )
#define SDL_SCANF_VARARG_FUNCV( fmtargnumber )
#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber )
#define SDL_WSCANF_VARARG_FUNC( fmtargnumber )
#else
#if defined(_MSC_VER) && (_MSC_VER >= 1600) /* VS 2010 and above */
#include <sal.h>

#define SDL_IN_BYTECAP(x) _In_bytecount_(x)
#define SDL_INOUT_Z_CAP(x) _Inout_z_cap_(x)
#define SDL_OUT_Z_CAP(x) _Out_z_cap_(x)
#define SDL_OUT_CAP(x) _Out_cap_(x)
#define SDL_OUT_BYTECAP(x) _Out_bytecap_(x)
#define SDL_OUT_Z_BYTECAP(x) _Out_z_bytecap_(x)

#define SDL_PRINTF_FORMAT_STRING _Printf_format_string_
#define SDL_SCANF_FORMAT_STRING _Scanf_format_string_impl_
#else
#define SDL_IN_BYTECAP(x)
#define SDL_INOUT_Z_CAP(x)
#define SDL_OUT_Z_CAP(x)
#define SDL_OUT_CAP(x)
#define SDL_OUT_BYTECAP(x)
#define SDL_OUT_Z_BYTECAP(x)
#define SDL_PRINTF_FORMAT_STRING
#define SDL_SCANF_FORMAT_STRING
#endif
#ifdef __GNUC__
#define SDL_PRINTF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __printf__, fmtargnumber, fmtargnumber+1 )))
#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __printf__, fmtargnumber, 0 )))
#define SDL_SCANF_VARARG_FUNC( fmtargnumber ) __attribute__ (( format( __scanf__, fmtargnumber, fmtargnumber+1 )))
#define SDL_SCANF_VARARG_FUNCV( fmtargnumber ) __attribute__(( format( __scanf__, fmtargnumber, 0 )))
#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber ) /* __attribute__ (( format( __wprintf__, fmtargnumber, fmtargnumber+1 ))) */
#define SDL_WSCANF_VARARG_FUNC( fmtargnumber ) /* __attribute__ (( format( __wscanf__, fmtargnumber, fmtargnumber+1 ))) */
#else
#define SDL_PRINTF_VARARG_FUNC( fmtargnumber )
#define SDL_PRINTF_VARARG_FUNCV( fmtargnumber )
#define SDL_SCANF_VARARG_FUNC( fmtargnumber )
#define SDL_SCANF_VARARG_FUNCV( fmtargnumber )
#define SDL_WPRINTF_VARARG_FUNC( fmtargnumber )
#define SDL_WSCANF_VARARG_FUNC( fmtargnumber )
#endif
#endif /* SDL_DISABLE_ANALYZE_MACROS */

#ifndef SDL_COMPILE_TIME_ASSERT
#if defined(__cplusplus)
/* Keep C++ case alone: Some versions of gcc will define __STDC_VERSION__ even when compiling in C++ mode. */
#if (__cplusplus >= 201103L)
#define SDL_COMPILE_TIME_ASSERT(name, x)  static_assert(x, #x)
#endif
#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 202311L)
#define SDL_COMPILE_TIME_ASSERT(name, x)  static_assert(x, #x)
#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
#define SDL_COMPILE_TIME_ASSERT(name, x) _Static_assert(x, #x)
#endif
#endif /* !SDL_COMPILE_TIME_ASSERT */

#ifndef SDL_COMPILE_TIME_ASSERT
/* universal, but may trigger -Wunused-local-typedefs */
#define SDL_COMPILE_TIME_ASSERT(name, x)               \
       typedef int SDL_compile_time_assert_ ## name[(x) * 2 - 1]
#endif

/** \cond */
#ifndef DOXYGEN_SHOULD_IGNORE_THIS
SDL_COMPILE_TIME_ASSERT(uint8, sizeof(Uint8) == 1);
SDL_COMPILE_TIME_ASSERT(sint8, sizeof(Sint8) == 1);
SDL_COMPILE_TIME_ASSERT(uint16, sizeof(Uint16) == 2);
SDL_COMPILE_TIME_ASSERT(sint16, sizeof(Sint16) == 2);
SDL_COMPILE_TIME_ASSERT(uint32, sizeof(Uint32) == 4);
SDL_COMPILE_TIME_ASSERT(sint32, sizeof(Sint32) == 4);
SDL_COMPILE_TIME_ASSERT(uint64, sizeof(Uint64) == 8);
SDL_COMPILE_TIME_ASSERT(sint64, sizeof(Sint64) == 8);
#endif /* DOXYGEN_SHOULD_IGNORE_THIS */
/** \endcond */

/* Check to make sure enums are the size of ints, for structure packing.
   For both Watcom C/C++ and Borland C/C++ the compiler option that makes
   enums having the size of an int must be enabled.
   This is "-b" for Borland C/C++ and "-ei" for Watcom C/C++ (v11).
*/

/** \cond */
#ifndef DOXYGEN_SHOULD_IGNORE_THIS
#if !defined(SDL_PLATFORM_VITA) && !defined(SDL_PLATFORM_3DS)
/* TODO: include/SDL_stdinc.h:390: error: size of array 'SDL_dummy_enum' is negative */
typedef enum SDL_DUMMY_ENUM
{
    DUMMY_ENUM_VALUE
} SDL_DUMMY_ENUM;

SDL_COMPILE_TIME_ASSERT(enum, sizeof(SDL_DUMMY_ENUM) == sizeof(int));
#endif
#endif /* DOXYGEN_SHOULD_IGNORE_THIS */
/** \endcond */

#include <SDL3/SDL_begin_code.h>
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

#ifndef SDL_DISABLE_ALLOCA
#define SDL_stack_alloc(type, count)    (type*)alloca(sizeof(type)*(count))
#define SDL_stack_free(data)
#else
#define SDL_stack_alloc(type, count)    (type*)SDL_malloc(sizeof(type)*(count))
#define SDL_stack_free(data)            SDL_free(data)
#endif

extern SDL_DECLSPEC SDL_MALLOC void * SDLCALL SDL_malloc(size_t size);
extern SDL_DECLSPEC SDL_MALLOC SDL_ALLOC_SIZE2(1, 2) void * SDLCALL SDL_calloc(size_t nmemb, size_t size);
extern SDL_DECLSPEC SDL_ALLOC_SIZE(2) void * SDLCALL SDL_realloc(void *mem, size_t size);
extern SDL_DECLSPEC void SDLCALL SDL_free(void *mem);

typedef void *(SDLCALL *SDL_malloc_func)(size_t size);
typedef void *(SDLCALL *SDL_calloc_func)(size_t nmemb, size_t size);
typedef void *(SDLCALL *SDL_realloc_func)(void *mem, size_t size);
typedef void (SDLCALL *SDL_free_func)(void *mem);

/**
 * Get the original set of SDL memory functions.
 *
 * This is what SDL_malloc and friends will use by default, if there has been
 * no call to SDL_SetMemoryFunctions. This is not necessarily using the C
 * runtime's `malloc` functions behind the scenes! Different platforms and
 * build configurations might do any number of unexpected things.
 *
 * \param malloc_func filled with malloc function.
 * \param calloc_func filled with calloc function.
 * \param realloc_func filled with realloc function.
 * \param free_func filled with free function.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC void SDLCALL SDL_GetOriginalMemoryFunctions(SDL_malloc_func *malloc_func,
                                                            SDL_calloc_func *calloc_func,
                                                            SDL_realloc_func *realloc_func,
                                                            SDL_free_func *free_func);

/**
 * Get the current set of SDL memory functions.
 *
 * \param malloc_func filled with malloc function.
 * \param calloc_func filled with calloc function.
 * \param realloc_func filled with realloc function.
 * \param free_func filled with free function.
 *
 * \threadsafety This does not hold a lock, so do not call this in the
 *               unlikely event of a background thread calling
 *               SDL_SetMemoryFunctions simultaneously.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_SetMemoryFunctions
 * \sa SDL_GetOriginalMemoryFunctions
 */
extern SDL_DECLSPEC void SDLCALL SDL_GetMemoryFunctions(SDL_malloc_func *malloc_func,
                                                    SDL_calloc_func *calloc_func,
                                                    SDL_realloc_func *realloc_func,
                                                    SDL_free_func *free_func);

/**
 * Replace SDL's memory allocation functions with a custom set.
 *
 * It is not safe to call this function once any allocations have been made,
 * as future calls to SDL_free will use the new allocator, even if they came
 * from an SDL_malloc made with the old one!
 *
 * If used, usually this needs to be the first call made into the SDL library,
 * if not the very first thing done at program startup time.
 *
 * \param malloc_func custom malloc function.
 * \param calloc_func custom calloc function.
 * \param realloc_func custom realloc function.
 * \param free_func custom free function.
 * \returns 0 on success or a negative error code on failure; call
 *          SDL_GetError() for more information.
 *
 * \threadsafety It is safe to call this function from any thread, but one
 *               should not replace the memory functions once any allocations
 *               are made!
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_GetMemoryFunctions
 * \sa SDL_GetOriginalMemoryFunctions
 */
extern SDL_DECLSPEC int SDLCALL SDL_SetMemoryFunctions(SDL_malloc_func malloc_func,
                                                   SDL_calloc_func calloc_func,
                                                   SDL_realloc_func realloc_func,
                                                   SDL_free_func free_func);

/**
 * Allocate memory aligned to a specific value.
 *
 * If `alignment` is less than the size of `void *`, then it will be increased
 * to match that.
 *
 * The returned memory address will be a multiple of the alignment value, and
 * the amount of memory allocated will be a multiple of the alignment value.
 *
 * The memory returned by this function must be freed with SDL_aligned_free(),
 * and _not_ SDL_free.
 *
 * \param alignment the alignment requested.
 * \param size the size to allocate.
 * \returns a pointer to the aligned memory.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_aligned_free
 */
extern SDL_DECLSPEC SDL_MALLOC void * SDLCALL SDL_aligned_alloc(size_t alignment, size_t size);

/**
 * Free memory allocated by SDL_aligned_alloc().
 *
 * The pointer is no longer valid after this call and cannot be dereferenced
 * anymore.
 *
 * \param mem a pointer previously returned by SDL_aligned_alloc.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_aligned_alloc
 */
extern SDL_DECLSPEC void SDLCALL SDL_aligned_free(void *mem);

/**
 * Get the number of outstanding (unfreed) allocations.
 *
 * \returns the number of allocations.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_GetNumAllocations(void);

extern SDL_DECLSPEC char * SDLCALL SDL_getenv(const char *name);
extern SDL_DECLSPEC int SDLCALL SDL_setenv(const char *name, const char *value, int overwrite);

typedef int (SDLCALL *SDL_CompareCallback)(const void *a, const void *b);
extern SDL_DECLSPEC void SDLCALL SDL_qsort(void *base, size_t nmemb, size_t size, SDL_CompareCallback compare);
extern SDL_DECLSPEC void * SDLCALL SDL_bsearch(const void *key, const void *base, size_t nmemb, size_t size, SDL_CompareCallback compare);

typedef int (SDLCALL *SDL_CompareCallback_r)(void *userdata, const void *a, const void *b);
extern SDL_DECLSPEC void SDLCALL SDL_qsort_r(void *base, size_t nmemb, size_t size, SDL_CompareCallback_r compare, void *userdata);
extern SDL_DECLSPEC void * SDLCALL SDL_bsearch_r(const void *key, const void *base, size_t nmemb, size_t size, SDL_CompareCallback_r compare, void *userdata);

extern SDL_DECLSPEC int SDLCALL SDL_abs(int x);

/* NOTE: these double-evaluate their arguments, so you should never have side effects in the parameters */
#define SDL_min(x, y) (((x) < (y)) ? (x) : (y))
#define SDL_max(x, y) (((x) > (y)) ? (x) : (y))
#define SDL_clamp(x, a, b) (((x) < (a)) ? (a) : (((x) > (b)) ? (b) : (x)))

/**
 * Query if a character is alphabetic (a letter).
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * for English 'a-z' and 'A-Z' as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isalpha(int x);

/**
 * Query if a character is alphabetic (a letter) or a number.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * for English 'a-z', 'A-Z', and '0-9' as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isalnum(int x);

/**
 * Report if a character is blank (a space or tab).
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * 0x20 (space) or 0x9 (tab) as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isblank(int x);

/**
 * Report if a character is a control character.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * 0 through 0x1F, and 0x7F, as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_iscntrl(int x);

/**
 * Report if a character is a numeric digit.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * '0' (0x30) through '9' (0x39), as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isdigit(int x);

/**
 * Report if a character is a hexadecimal digit.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * 'A' through 'F', 'a' through 'f', and '0' through '9', as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isxdigit(int x);

/**
 * Report if a character is a punctuation mark.
 *
 * **WARNING**: Regardless of system locale, this is equivalent to
 * `((SDL_isgraph(x)) && (!SDL_isalnum(x)))`.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isgraph
 * \sa SDL_isalnum
 */
extern SDL_DECLSPEC int SDLCALL SDL_ispunct(int x);

/**
 * Report if a character is whitespace.
 *
 * **WARNING**: Regardless of system locale, this will only treat the
 * following ASCII values as true:
 *
 * - space (0x20)
 * - tab (0x09)
 * - newline (0x0A)
 * - vertical tab (0x0B)
 * - form feed (0x0C)
 * - return (0x0D)
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isspace(int x);

/**
 * Report if a character is upper case.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * 'A' through 'Z' as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isupper(int x);

/**
 * Report if a character is lower case.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * 'a' through 'z' as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_islower(int x);

/**
 * Report if a character is "printable".
 *
 * Be advised that "printable" has a definition that goes back to text
 * terminals from the dawn of computing, making this a sort of special case
 * function that is not suitable for Unicode (or most any) text management.
 *
 * **WARNING**: Regardless of system locale, this will only treat ASCII values
 * ' ' (0x20) through '~' (0x7E) as true.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_isprint(int x);

/**
 * Report if a character is any "printable" except space.
 *
 * Be advised that "printable" has a definition that goes back to text
 * terminals from the dawn of computing, making this a sort of special case
 * function that is not suitable for Unicode (or most any) text management.
 *
 * **WARNING**: Regardless of system locale, this is equivalent to
 * `(SDL_isprint(x)) && ((x) != ' ')`.
 *
 * \param x character value to check.
 * \returns non-zero if x falls within the character class, zero otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isprint
 */
extern SDL_DECLSPEC int SDLCALL SDL_isgraph(int x);

/**
 * Convert low-ASCII English letters to uppercase.
 *
 * **WARNING**: Regardless of system locale, this will only convert ASCII
 * values 'a' through 'z' to uppercase.
 *
 * This function returns the uppercase equivalent of `x`. If a character
 * cannot be converted, or is already uppercase, this function returns `x`.
 *
 * \param x character value to check.
 * \returns capitalized version of x, or x if no conversion available.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_toupper(int x);

/**
 * Convert low-ASCII English letters to lowercase.
 *
 * **WARNING**: Regardless of system locale, this will only convert ASCII
 * values 'A' through 'Z' to lowercase.
 *
 * This function returns the lowercase equivalent of `x`. If a character
 * cannot be converted, or is already lowercase, this function returns `x`.
 *
 * \param x character value to check.
 * \returns lowercase version of x, or x if no conversion available.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_tolower(int x);

extern SDL_DECLSPEC Uint16 SDLCALL SDL_crc16(Uint16 crc, const void *data, size_t len);
extern SDL_DECLSPEC Uint32 SDLCALL SDL_crc32(Uint32 crc, const void *data, size_t len);

extern SDL_DECLSPEC void * SDLCALL SDL_memcpy(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);

/* Take advantage of compiler optimizations for memcpy */
#ifndef SDL_SLOW_MEMCPY
#ifdef SDL_memcpy
#undef SDL_memcpy
#endif
#define SDL_memcpy  memcpy
#endif

#define SDL_copyp(dst, src)                                                                 \
    { SDL_COMPILE_TIME_ASSERT(SDL_copyp, sizeof (*(dst)) == sizeof (*(src))); }             \
    SDL_memcpy((dst), (src), sizeof(*(src)))

extern SDL_DECLSPEC void * SDLCALL SDL_memmove(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);

/* Take advantage of compiler optimizations for memmove */
#ifndef SDL_SLOW_MEMMOVE
#ifdef SDL_memmove
#undef SDL_memmove
#endif
#define SDL_memmove memmove
#endif

extern SDL_DECLSPEC void * SDLCALL SDL_memset(SDL_OUT_BYTECAP(len) void *dst, int c, size_t len);
extern SDL_DECLSPEC void * SDLCALL SDL_memset4(void *dst, Uint32 val, size_t dwords);

/* Take advantage of compiler optimizations for memset */
#ifndef SDL_SLOW_MEMSET
#ifdef SDL_memset
#undef SDL_memset
#endif
#define SDL_memset  memset
#endif

#define SDL_zero(x) SDL_memset(&(x), 0, sizeof((x)))
#define SDL_zerop(x) SDL_memset((x), 0, sizeof(*(x)))
#define SDL_zeroa(x) SDL_memset((x), 0, sizeof((x)))

extern SDL_DECLSPEC int SDLCALL SDL_memcmp(const void *s1, const void *s2, size_t len);

extern SDL_DECLSPEC size_t SDLCALL SDL_wcslen(const wchar_t *wstr);
extern SDL_DECLSPEC size_t SDLCALL SDL_wcsnlen(const wchar_t *wstr, size_t maxlen);
extern SDL_DECLSPEC size_t SDLCALL SDL_wcslcpy(SDL_OUT_Z_CAP(maxlen) wchar_t *dst, const wchar_t *src, size_t maxlen);
extern SDL_DECLSPEC size_t SDLCALL SDL_wcslcat(SDL_INOUT_Z_CAP(maxlen) wchar_t *dst, const wchar_t *src, size_t maxlen);
extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsdup(const wchar_t *wstr);
extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsstr(const wchar_t *haystack, const wchar_t *needle);
extern SDL_DECLSPEC wchar_t * SDLCALL SDL_wcsnstr(const wchar_t *haystack, const wchar_t *needle, size_t maxlen);

/**
 * Compare two null-terminated wide strings.
 *
 * This only compares wchar_t values until it hits a null-terminating
 * character; it does not care if the string is well-formed UTF-16 (or UTF-32,
 * depending on your platform's wchar_t size), or uses valid Unicode values.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_wcscmp(const wchar_t *str1, const wchar_t *str2);

/**
 * Compare two wide strings up to a number of wchar_t values.
 *
 * This only compares wchar_t values; it does not care if the string is
 * well-formed UTF-16 (or UTF-32, depending on your platform's wchar_t size),
 * or uses valid Unicode values.
 *
 * Note that while this function is intended to be used with UTF-16 (or
 * UTF-32, depending on your platform's definition of wchar_t), it is
 * comparing raw wchar_t values and not Unicode codepoints: `maxlen` specifies
 * a wchar_t limit! If the limit lands in the middle of a multi-wchar UTF-16
 * sequence, it will only compare a portion of the final character.
 *
 * `maxlen` specifies a maximum number of wchar_t to compare; if the strings
 * match to this number of wide chars (or both have matched to a
 * null-terminator character before this count), they will be considered
 * equal.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \param maxlen the maximum number of wchar_t to compare.
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_wcsncmp(const wchar_t *str1, const wchar_t *str2, size_t maxlen);

/**
 * Compare two null-terminated wide strings, case-insensitively.
 *
 * This will work with Unicode strings, using a technique called
 * "case-folding" to handle the vast majority of case-sensitive human
 * languages regardless of system locale. It can deal with expanding values: a
 * German Eszett character can compare against two ASCII 's' chars and be
 * considered a match, for example. A notable exception: it does not handle
 * the Turkish 'i' character; human language is complicated!
 *
 * Depending on your platform, "wchar_t" might be 2 bytes, and expected to be
 * UTF-16 encoded (like Windows), or 4 bytes in UTF-32 format. Since this
 * handles Unicode, it expects the string to be well-formed and not a
 * null-terminated string of arbitrary bytes. Characters that are not valid
 * UTF-16 (or UTF-32) are treated as Unicode character U+FFFD (REPLACEMENT
 * CHARACTER), which is to say two strings of random bits may turn out to
 * match if they convert to the same amount of replacement characters.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_wcscasecmp(const wchar_t *str1, const wchar_t *str2);

/**
 * Compare two wide strings, case-insensitively, up to a number of wchar_t.
 *
 * This will work with Unicode strings, using a technique called
 * "case-folding" to handle the vast majority of case-sensitive human
 * languages regardless of system locale. It can deal with expanding values: a
 * German Eszett character can compare against two ASCII 's' chars and be
 * considered a match, for example. A notable exception: it does not handle
 * the Turkish 'i' character; human language is complicated!
 *
 * Depending on your platform, "wchar_t" might be 2 bytes, and expected to be
 * UTF-16 encoded (like Windows), or 4 bytes in UTF-32 format. Since this
 * handles Unicode, it expects the string to be well-formed and not a
 * null-terminated string of arbitrary bytes. Characters that are not valid
 * UTF-16 (or UTF-32) are treated as Unicode character U+FFFD (REPLACEMENT
 * CHARACTER), which is to say two strings of random bits may turn out to
 * match if they convert to the same amount of replacement characters.
 *
 * Note that while this function might deal with variable-sized characters,
 * `maxlen` specifies a _wchar_ limit! If the limit lands in the middle of a
 * multi-byte UTF-16 sequence, it may convert a portion of the final character
 * to one or more Unicode character U+FFFD (REPLACEMENT CHARACTER) so as not
 * to overflow a buffer.
 *
 * `maxlen` specifies a maximum number of wchar_t values to compare; if the
 * strings match to this number of wchar_t (or both have matched to a
 * null-terminator character before this number of bytes), they will be
 * considered equal.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \param maxlen the maximum number of wchar_t values to compare.
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_wcsncasecmp(const wchar_t *str1, const wchar_t *str2, size_t maxlen);

extern SDL_DECLSPEC long SDLCALL SDL_wcstol(const wchar_t *str, wchar_t **endp, int base);

extern SDL_DECLSPEC size_t SDLCALL SDL_strlen(const char *str);
extern SDL_DECLSPEC size_t SDLCALL SDL_strnlen(const char *str, size_t maxlen);
extern SDL_DECLSPEC size_t SDLCALL SDL_strlcpy(SDL_OUT_Z_CAP(maxlen) char *dst, const char *src, size_t maxlen);
extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strlcpy(SDL_OUT_Z_CAP(dst_bytes) char *dst, const char *src, size_t dst_bytes);
extern SDL_DECLSPEC size_t SDLCALL SDL_strlcat(SDL_INOUT_Z_CAP(maxlen) char *dst, const char *src, size_t maxlen);
extern SDL_DECLSPEC SDL_MALLOC char * SDLCALL SDL_strdup(const char *str);
extern SDL_DECLSPEC SDL_MALLOC char * SDLCALL SDL_strndup(const char *str, size_t maxlen);
extern SDL_DECLSPEC char * SDLCALL SDL_strrev(char *str);

/**
 * Convert a string to uppercase.
 *
 * **WARNING**: Regardless of system locale, this will only convert ASCII
 * values 'A' through 'Z' to uppercase.
 *
 * This function operates on a null-terminated string of bytes--even if it is
 * malformed UTF-8!--and converts ASCII characters 'a' through 'z' to their
 * uppercase equivalents in-place, returning the original `str` pointer.
 *
 * \param str the string to convert in-place. Can not be NULL.
 * \returns the `str` pointer passed into this function.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_strlwr
 */
extern SDL_DECLSPEC char * SDLCALL SDL_strupr(char *str);

/**
 * Convert a string to lowercase.
 *
 * **WARNING**: Regardless of system locale, this will only convert ASCII
 * values 'A' through 'Z' to lowercase.
 *
 * This function operates on a null-terminated string of bytes--even if it is
 * malformed UTF-8!--and converts ASCII characters 'A' through 'Z' to their
 * lowercase equivalents in-place, returning the original `str` pointer.
 *
 * \param str the string to convert in-place. Can not be NULL.
 * \returns the `str` pointer passed into this function.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_strupr
 */
extern SDL_DECLSPEC char * SDLCALL SDL_strlwr(char *str);

extern SDL_DECLSPEC char * SDLCALL SDL_strchr(const char *str, int c);
extern SDL_DECLSPEC char * SDLCALL SDL_strrchr(const char *str, int c);
extern SDL_DECLSPEC char * SDLCALL SDL_strstr(const char *haystack, const char *needle);
extern SDL_DECLSPEC char * SDLCALL SDL_strnstr(const char *haystack, const char *needle, size_t maxlen);
extern SDL_DECLSPEC char * SDLCALL SDL_strcasestr(const char *haystack, const char *needle);
extern SDL_DECLSPEC char * SDLCALL SDL_strtok_r(char *s1, const char *s2, char **saveptr);
extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strlen(const char *str);
extern SDL_DECLSPEC size_t SDLCALL SDL_utf8strnlen(const char *str, size_t bytes);

extern SDL_DECLSPEC char * SDLCALL SDL_itoa(int value, char *str, int radix);
extern SDL_DECLSPEC char * SDLCALL SDL_uitoa(unsigned int value, char *str, int radix);
extern SDL_DECLSPEC char * SDLCALL SDL_ltoa(long value, char *str, int radix);
extern SDL_DECLSPEC char * SDLCALL SDL_ultoa(unsigned long value, char *str, int radix);
extern SDL_DECLSPEC char * SDLCALL SDL_lltoa(Sint64 value, char *str, int radix);
extern SDL_DECLSPEC char * SDLCALL SDL_ulltoa(Uint64 value, char *str, int radix);

extern SDL_DECLSPEC int SDLCALL SDL_atoi(const char *str);
extern SDL_DECLSPEC double SDLCALL SDL_atof(const char *str);
extern SDL_DECLSPEC long SDLCALL SDL_strtol(const char *str, char **endp, int base);
extern SDL_DECLSPEC unsigned long SDLCALL SDL_strtoul(const char *str, char **endp, int base);
extern SDL_DECLSPEC Sint64 SDLCALL SDL_strtoll(const char *str, char **endp, int base);
extern SDL_DECLSPEC Uint64 SDLCALL SDL_strtoull(const char *str, char **endp, int base);
extern SDL_DECLSPEC double SDLCALL SDL_strtod(const char *str, char **endp);

/**
 * Compare two null-terminated UTF-8 strings.
 *
 * Due to the nature of UTF-8 encoding, this will work with Unicode strings,
 * since effectively this function just compares bytes until it hits a
 * null-terminating character. Also due to the nature of UTF-8, this can be
 * used with SDL_qsort() to put strings in (roughly) alphabetical order.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_strcmp(const char *str1, const char *str2);

/**
 * Compare two UTF-8 strings up to a number of bytes.
 *
 * Due to the nature of UTF-8 encoding, this will work with Unicode strings,
 * since effectively this function just compares bytes until it hits a
 * null-terminating character. Also due to the nature of UTF-8, this can be
 * used with SDL_qsort() to put strings in (roughly) alphabetical order.
 *
 * Note that while this function is intended to be used with UTF-8, it is
 * doing a bytewise comparison, and `maxlen` specifies a _byte_ limit! If the
 * limit lands in the middle of a multi-byte UTF-8 sequence, it will only
 * compare a portion of the final character.
 *
 * `maxlen` specifies a maximum number of bytes to compare; if the strings
 * match to this number of bytes (or both have matched to a null-terminator
 * character before this number of bytes), they will be considered equal.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \param maxlen the maximum number of _bytes_ to compare.
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_strncmp(const char *str1, const char *str2, size_t maxlen);

/**
 * Compare two null-terminated UTF-8 strings, case-insensitively.
 *
 * This will work with Unicode strings, using a technique called
 * "case-folding" to handle the vast majority of case-sensitive human
 * languages regardless of system locale. It can deal with expanding values: a
 * German Eszett character can compare against two ASCII 's' chars and be
 * considered a match, for example. A notable exception: it does not handle
 * the Turkish 'i' character; human language is complicated!
 *
 * Since this handles Unicode, it expects the string to be well-formed UTF-8
 * and not a null-terminated string of arbitrary bytes. Bytes that are not
 * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
 * CHARACTER), which is to say two strings of random bits may turn out to
 * match if they convert to the same amount of replacement characters.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_strcasecmp(const char *str1, const char *str2);


/**
 * Compare two UTF-8 strings, case-insensitively, up to a number of bytes.
 *
 * This will work with Unicode strings, using a technique called
 * "case-folding" to handle the vast majority of case-sensitive human
 * languages regardless of system locale. It can deal with expanding values: a
 * German Eszett character can compare against two ASCII 's' chars and be
 * considered a match, for example. A notable exception: it does not handle
 * the Turkish 'i' character; human language is complicated!
 *
 * Since this handles Unicode, it expects the string to be well-formed UTF-8
 * and not a null-terminated string of arbitrary bytes. Bytes that are not
 * valid UTF-8 are treated as Unicode character U+FFFD (REPLACEMENT
 * CHARACTER), which is to say two strings of random bits may turn out to
 * match if they convert to the same amount of replacement characters.
 *
 * Note that while this function is intended to be used with UTF-8, `maxlen`
 * specifies a _byte_ limit! If the limit lands in the middle of a multi-byte
 * UTF-8 sequence, it may convert a portion of the final character to one or
 * more Unicode character U+FFFD (REPLACEMENT CHARACTER) so as not to overflow
 * a buffer.
 *
 * `maxlen` specifies a maximum number of bytes to compare; if the strings
 * match to this number of bytes (or both have matched to a null-terminator
 * character before this number of bytes), they will be considered equal.
 *
 * \param str1 the first string to compare. NULL is not permitted!
 * \param str2 the second string to compare. NULL is not permitted!
 * \param maxlen the maximum number of bytes to compare.
 * \returns less than zero if str1 is "less than" str2, greater than zero if
 *          str1 is "greater than" str2, and zero if the strings match
 *          exactly.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC int SDLCALL SDL_strncasecmp(const char *str1, const char *str2, size_t maxlen);

/**
 * The Unicode REPLACEMENT CHARACTER codepoint.
 *
 * SDL_StepUTF8() reports this codepoint when it encounters a UTF-8 string
 * with encoding errors.
 *
 * This tends to render as something like a question mark in most places.
 *
 * \since This macro is available since SDL 3.0.0.
 *
 * \sa SDL_StepUTF8
 */
#define SDL_INVALID_UNICODE_CODEPOINT 0xFFFD

/**
 * Decode a UTF-8 string, one Unicode codepoint at a time.
 *
 * This will return the first Unicode codepoint in the UTF-8 encoded string in
 * `*pstr`, and then advance `*pstr` past any consumed bytes before returning.
 *
 * It will not access more than `*pslen` bytes from the string. `*pslen` will
 * be adjusted, as well, subtracting the number of bytes consumed.
 *
 * `pslen` is allowed to be NULL, in which case the string _must_ be
 * NULL-terminated, as the function will blindly read until it sees the NULL
 * char.
 *
 * if `*pslen` is zero, it assumes the end of string is reached and returns a
 * zero codepoint regardless of the contents of the string buffer.
 *
 * If the resulting codepoint is zero (a NULL terminator), or `*pslen` is
 * zero, it will not advance `*pstr` or `*pslen` at all.
 *
 * Generally this function is called in a loop until it returns zero,
 * adjusting its parameters each iteration.
 *
 * If an invalid UTF-8 sequence is encountered, this function returns
 * SDL_INVALID_UNICODE_CODEPOINT and advances the string/length by one byte
 * (which is to say, a multibyte sequence might produce several
 * SDL_INVALID_UNICODE_CODEPOINT returns before it syncs to the next valid
 * UTF-8 sequence).
 *
 * Several things can generate invalid UTF-8 sequences, including overlong
 * encodings, the use of UTF-16 surrogate values, and truncated data. Please
 * refer to
 * [RFC3629](https://www.ietf.org/rfc/rfc3629.txt)
 * for details.
 *
 * \param pstr a pointer to a UTF-8 string pointer to be read and adjusted.
 * \param pslen a pointer to the number of bytes in the string, to be read and
 *              adjusted. NULL is allowed.
 * \returns the first Unicode codepoint in the string.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC Uint32 SDLCALL SDL_StepUTF8(const char **pstr, size_t *pslen);

/**
 * Convert a single Unicode codepoint to UTF-8.
 *
 * The buffer pointed to by `dst` must be at least 4 bytes long, as this
 * function may generate between 1 and 4 bytes of output.
 *
 * This function returns the first byte _after_ the newly-written UTF-8
 * sequence, which is useful for encoding multiple codepoints in a loop, or
 * knowing where to write a NULL-terminator character to end the string (in
 * either case, plan to have a buffer of _more_ than 4 bytes!).
 *
 * If `codepoint` is an invalid value (outside the Unicode range, or a UTF-16
 * surrogate value, etc), this will use U+FFFD (REPLACEMENT CHARACTER) for the
 * codepoint instead, and not set an error.
 *
 * If `dst` is NULL, this returns NULL immediately without writing to the
 * pointer and without setting an error.
 *
 * \param codepoint a Unicode codepoint to convert to UTF-8.
 * \param dst the location to write the encoded UTF-8. Must point to at least
 *            4 bytes!
 * \returns the first byte past the newly-written UTF-8 sequence.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC char * SDLCALL SDL_UCS4ToUTF8(Uint32 codepoint, char *dst);


extern SDL_DECLSPEC int SDLCALL SDL_sscanf(const char *text, SDL_SCANF_FORMAT_STRING const char *fmt, ...) SDL_SCANF_VARARG_FUNC(2);
extern SDL_DECLSPEC int SDLCALL SDL_vsscanf(const char *text, SDL_SCANF_FORMAT_STRING const char *fmt, va_list ap) SDL_SCANF_VARARG_FUNCV(2);
extern SDL_DECLSPEC int SDLCALL SDL_snprintf(SDL_OUT_Z_CAP(maxlen) char *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const char *fmt, ... ) SDL_PRINTF_VARARG_FUNC(3);
extern SDL_DECLSPEC int SDLCALL SDL_swprintf(SDL_OUT_Z_CAP(maxlen) wchar_t *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const wchar_t *fmt, ... ) SDL_WPRINTF_VARARG_FUNC(3);
extern SDL_DECLSPEC int SDLCALL SDL_vsnprintf(SDL_OUT_Z_CAP(maxlen) char *text, size_t maxlen, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(3);
extern SDL_DECLSPEC int SDLCALL SDL_vswprintf(SDL_OUT_Z_CAP(maxlen) wchar_t *text, size_t maxlen, const wchar_t *fmt, va_list ap);
extern SDL_DECLSPEC int SDLCALL SDL_asprintf(char **strp, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
extern SDL_DECLSPEC int SDLCALL SDL_vasprintf(char **strp, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2);

/**
 * Seeds the pseudo-random number generator.
 *
 * Reusing the seed number will cause SDL_rand_*() to repeat the same stream
 * of 'random' numbers.
 *
 * \param seed the value to use as a random number seed, or 0 to use
 *             SDL_GetPerformanceCounter().
 *
 * \threadsafety This should be called on the same thread that calls
 *               SDL_rand*()
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_rand
 * \sa SDL_rand_bits
 * \sa SDL_randf
 */
extern SDL_DECLSPEC void SDLCALL SDL_srand(Uint64 seed);

/**
 * Generate a pseudo-random number less than n for positive n
 *
 * The method used is faster and of better quality than `rand() % n`. Odds are
 * roughly 99.9% even for n = 1 million. Evenness is better for smaller n, and
 * much worse as n gets bigger.
 *
 * Example: to simulate a d6 use `SDL_rand(6) + 1` The +1 converts 0..5 to
 * 1..6
 *
 * If you want to generate a pseudo-random number in the full range of Sint32,
 * you should use: (Sint32)SDL_rand_bits()
 *
 * If you want reproducible output, be sure to initialize with SDL_srand()
 * first.
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \param n the number of possible outcomes. n must be positive.
 * \returns a random value in the range of [0 .. n-1].
 *
 * \threadsafety All calls should be made from a single thread
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_srand
 * \sa SDL_randf
 */
extern SDL_DECLSPEC Sint32 SDLCALL SDL_rand(Sint32 n);

/**
 * Generate a uniform pseudo-random floating point number less than 1.0
 *
 * If you want reproducible output, be sure to initialize with SDL_srand()
 * first.
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \returns a random value in the range of [0.0, 1.0).
 *
 * \threadsafety All calls should be made from a single thread
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_srand
 * \sa SDL_rand
 */
extern SDL_DECLSPEC float SDLCALL SDL_randf(void);

/**
 * Generate 32 pseudo-random bits.
 *
 * You likely want to use SDL_rand() to get a psuedo-random number instead.
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \returns a random value in the range of [0-SDL_MAX_UINT32].
 *
 * \threadsafety All calls should be made from a single thread
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_rand
 * \sa SDL_randf
 * \sa SDL_srand
 */
extern SDL_DECLSPEC Uint32 SDLCALL SDL_rand_bits(void);

/**
 * Generate a pseudo-random number less than n for positive n
 *
 * The method used is faster and of better quality than `rand() % n`. Odds are
 * roughly 99.9% even for n = 1 million. Evenness is better for smaller n, and
 * much worse as n gets bigger.
 *
 * Example: to simulate a d6 use `SDL_rand_r(state, 6) + 1` The +1 converts
 * 0..5 to 1..6
 *
 * If you want to generate a pseudo-random number in the full range of Sint32,
 * you should use: (Sint32)SDL_rand_bits_r(state)
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \param state a pointer to the current random number state, this may not be
 *              NULL.
 * \param n the number of possible outcomes. n must be positive.
 * \returns a random value in the range of [0 .. n-1].
 *
 * \threadsafety This function is thread-safe, as long as the state pointer
 *               isn't shared between threads.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_rand
 * \sa SDL_rand_bits_r
 * \sa SDL_randf_r
 */
extern SDL_DECLSPEC Sint32 SDLCALL SDL_rand_r(Uint64 *state, Sint32 n);

/**
 * Generate a uniform pseudo-random floating point number less than 1.0
 *
 * If you want reproducible output, be sure to initialize with SDL_srand()
 * first.
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \param state a pointer to the current random number state, this may not be
 *              NULL.
 * \returns a random value in the range of [0.0, 1.0).
 *
 * \threadsafety This function is thread-safe, as long as the state pointer
 *               isn't shared between threads.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_rand_bits_r
 * \sa SDL_rand_r
 * \sa SDL_randf
 */
extern SDL_DECLSPEC float SDLCALL SDL_randf_r(Uint64 *state);

/**
 * Generate 32 pseudo-random bits.
 *
 * You likely want to use SDL_rand_r() to get a psuedo-random number instead.
 *
 * There are no guarantees as to the quality of the random sequence produced,
 * and this should not be used for security (cryptography, passwords) or where
 * money is on the line (loot-boxes, casinos). There are many random number
 * libraries available with different characteristics and you should pick one
 * of those to meet any serious needs.
 *
 * \param state a pointer to the current random number state, this may not be
 *              NULL.
 * \returns a random value in the range of [0-SDL_MAX_UINT32].
 *
 * \threadsafety This function is thread-safe, as long as the state pointer
 *               isn't shared between threads.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_rand_r
 * \sa SDL_randf_r
 */
extern SDL_DECLSPEC Uint32 SDLCALL SDL_rand_bits_r(Uint64 *state);


#ifndef SDL_PI_D
#define SDL_PI_D   3.141592653589793238462643383279502884       /**< pi (double) */
#endif
#ifndef SDL_PI_F
#define SDL_PI_F   3.141592653589793238462643383279502884F      /**< pi (float) */
#endif

/**
 * Compute the arc cosine of `x`.
 *
 * The definition of `y = acos(x)` is `x = cos(y)`.
 *
 * Domain: `-1 <= x <= 1`
 *
 * Range: `0 <= y <= Pi`
 *
 * This function operates on double-precision floating point values, use
 * SDL_acosf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc cosine of `x`, in radians.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_acosf
 * \sa SDL_asin
 * \sa SDL_cos
 */
extern SDL_DECLSPEC double SDLCALL SDL_acos(double x);

/**
 * Compute the arc cosine of `x`.
 *
 * The definition of `y = acos(x)` is `x = cos(y)`.
 *
 * Domain: `-1 <= x <= 1`
 *
 * Range: `0 <= y <= Pi`
 *
 * This function operates on single-precision floating point values, use
 * SDL_acos for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc cosine of `x`, in radians.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_acos
 * \sa SDL_asinf
 * \sa SDL_cosf
 */
extern SDL_DECLSPEC float SDLCALL SDL_acosf(float x);

/**
 * Compute the arc sine of `x`.
 *
 * The definition of `y = asin(x)` is `x = sin(y)`.
 *
 * Domain: `-1 <= x <= 1`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on double-precision floating point values, use
 * SDL_asinf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc sine of `x`, in radians.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_asinf
 * \sa SDL_acos
 * \sa SDL_sin
 */
extern SDL_DECLSPEC double SDLCALL SDL_asin(double x);

/**
 * Compute the arc sine of `x`.
 *
 * The definition of `y = asin(x)` is `x = sin(y)`.
 *
 * Domain: `-1 <= x <= 1`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on single-precision floating point values, use
 * SDL_asin for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc sine of `x`, in radians.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_asin
 * \sa SDL_acosf
 * \sa SDL_sinf
 */
extern SDL_DECLSPEC float SDLCALL SDL_asinf(float x);

/**
 * Compute the arc tangent of `x`.
 *
 * The definition of `y = atan(x)` is `x = tan(y)`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on double-precision floating point values, use
 * SDL_atanf for single-precision floats.
 *
 * To calculate the arc tangent of y / x, use SDL_atan2.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc tangent of of `x` in radians, or 0 if `x = 0`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_atanf
 * \sa SDL_atan2
 * \sa SDL_tan
 */
extern SDL_DECLSPEC double SDLCALL SDL_atan(double x);

/**
 * Compute the arc tangent of `x`.
 *
 * The definition of `y = atan(x)` is `x = tan(y)`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on single-precision floating point values, use
 * SDL_atan for dboule-precision floats.
 *
 * To calculate the arc tangent of y / x, use SDL_atan2f.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns arc tangent of of `x` in radians, or 0 if `x = 0`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_atan
 * \sa SDL_atan2f
 * \sa SDL_tanf
 */
extern SDL_DECLSPEC float SDLCALL SDL_atanf(float x);

/**
 * Compute the arc tangent of `y / x`, using the signs of x and y to adjust
 * the result's quadrant.
 *
 * The definition of `z = atan2(x, y)` is `y = x tan(z)`, where the quadrant
 * of z is determined based on the signs of x and y.
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on double-precision floating point values, use
 * SDL_atan2f for single-precision floats.
 *
 * To calculate the arc tangent of a single value, use SDL_atan.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param y floating point value of the numerator (y coordinate).
 * \param x floating point value of the denominator (x coordinate).
 * \returns arc tangent of of `y / x` in radians, or, if `x = 0`, either
 *          `-Pi/2`, `0`, or `Pi/2`, depending on the value of `y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_atan2f
 * \sa SDL_atan
 * \sa SDL_tan
 */
extern SDL_DECLSPEC double SDLCALL SDL_atan2(double y, double x);

/**
 * Compute the arc tangent of `y / x`, using the signs of x and y to adjust
 * the result's quadrant.
 *
 * The definition of `z = atan2(x, y)` is `y = x tan(z)`, where the quadrant
 * of z is determined based on the signs of x and y.
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
 *
 * Range: `-Pi/2 <= y <= Pi/2`
 *
 * This function operates on single-precision floating point values, use
 * SDL_atan2 for double-precision floats.
 *
 * To calculate the arc tangent of a single value, use SDL_atanf.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param y floating point value of the numerator (y coordinate).
 * \param x floating point value of the denominator (x coordinate).
 * \returns arc tangent of of `y / x` in radians, or, if `x = 0`, either
 *          `-Pi/2`, `0`, or `Pi/2`, depending on the value of `y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_atan2f
 * \sa SDL_atan
 * \sa SDL_tan
 */
extern SDL_DECLSPEC float SDLCALL SDL_atan2f(float y, float x);

/**
 * Compute the ceiling of `x`.
 *
 * The ceiling of `x` is the smallest integer `y` such that `y > x`, i.e `x`
 * rounded up to the nearest integer.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on double-precision floating point values, use
 * SDL_ceilf for single-precision floats.
 *
 * \param x floating point value.
 * \returns the ceiling of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_ceilf
 * \sa SDL_floor
 * \sa SDL_trunc
 * \sa SDL_round
 * \sa SDL_lround
 */
extern SDL_DECLSPEC double SDLCALL SDL_ceil(double x);

/**
 * Compute the ceiling of `x`.
 *
 * The ceiling of `x` is the smallest integer `y` such that `y > x`, i.e `x`
 * rounded up to the nearest integer.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on single-precision floating point values, use
 * SDL_ceil for double-precision floats.
 *
 * \param x floating point value.
 * \returns the ceiling of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_ceil
 * \sa SDL_floorf
 * \sa SDL_truncf
 * \sa SDL_roundf
 * \sa SDL_lroundf
 */
extern SDL_DECLSPEC float SDLCALL SDL_ceilf(float x);

/**
 * Copy the sign of one floating-point value to another.
 *
 * The definition of copysign is that ``copysign(x, y) = abs(x) * sign(y)``.
 *
 * Domain: `-INF <= x <= INF`, ``-INF <= y <= f``
 *
 * Range: `-INF <= z <= INF`
 *
 * This function operates on double-precision floating point values, use
 * SDL_copysignf for single-precision floats.
 *
 * \param x floating point value to use as the magnitude.
 * \param y floating point value to use as the sign.
 * \returns the floating point value with the sign of y and the magnitude of
 *          x.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_copysignf
 * \sa SDL_fabs
 */
extern SDL_DECLSPEC double SDLCALL SDL_copysign(double x, double y);

/**
 * Copy the sign of one floating-point value to another.
 *
 * The definition of copysign is that ``copysign(x, y) = abs(x) * sign(y)``.
 *
 * Domain: `-INF <= x <= INF`, ``-INF <= y <= f``
 *
 * Range: `-INF <= z <= INF`
 *
 * This function operates on single-precision floating point values, use
 * SDL_copysign for double-precision floats.
 *
 * \param x floating point value to use as the magnitude.
 * \param y floating point value to use as the sign.
 * \returns the floating point value with the sign of y and the magnitude of
 *          x.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_copysignf
 * \sa SDL_fabsf
 */
extern SDL_DECLSPEC float SDLCALL SDL_copysignf(float x, float y);

/**
 * Compute the cosine of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-1 <= y <= 1`
 *
 * This function operates on double-precision floating point values, use
 * SDL_cosf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns cosine of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_cosf
 * \sa SDL_acos
 * \sa SDL_sin
 */
extern SDL_DECLSPEC double SDLCALL SDL_cos(double x);

/**
 * Compute the cosine of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-1 <= y <= 1`
 *
 * This function operates on single-precision floating point values, use
 * SDL_cos for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns cosine of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_cos
 * \sa SDL_acosf
 * \sa SDL_sinf
 */
extern SDL_DECLSPEC float SDLCALL SDL_cosf(float x);

/**
 * Compute the exponential of `x`.
 *
 * The definition of `y = exp(x)` is `y = e^x`, where `e` is the base of the
 * natural logarithm. The inverse is the natural logarithm, SDL_log.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * The output will overflow if `exp(x)` is too large to be represented.
 *
 * This function operates on double-precision floating point values, use
 * SDL_expf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns value of `e^x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_expf
 * \sa SDL_log
 */
extern SDL_DECLSPEC double SDLCALL SDL_exp(double x);

/**
 * Compute the exponential of `x`.
 *
 * The definition of `y = exp(x)` is `y = e^x`, where `e` is the base of the
 * natural logarithm. The inverse is the natural logarithm, SDL_logf.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * The output will overflow if `exp(x)` is too large to be represented.
 *
 * This function operates on single-precision floating point values, use
 * SDL_exp for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value.
 * \returns value of `e^x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_exp
 * \sa SDL_logf
 */
extern SDL_DECLSPEC float SDLCALL SDL_expf(float x);

/**
 * Compute the absolute value of `x`
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * This function operates on double-precision floating point values, use
 * SDL_copysignf for single-precision floats.
 *
 * \param x floating point value to use as the magnitude.
 * \returns the absolute value of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_fabsf
 */
extern SDL_DECLSPEC double SDLCALL SDL_fabs(double x);

/**
 * Compute the absolute value of `x`
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * This function operates on single-precision floating point values, use
 * SDL_copysignf for double-precision floats.
 *
 * \param x floating point value to use as the magnitude.
 * \returns the absolute value of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_fabs
 */
extern SDL_DECLSPEC float SDLCALL SDL_fabsf(float x);

/**
 * Compute the floor of `x`.
 *
 * The floor of `x` is the largest integer `y` such that `y > x`, i.e `x`
 * rounded down to the nearest integer.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on double-precision floating point values, use
 * SDL_floorf for single-precision floats.
 *
 * \param x floating point value.
 * \returns the floor of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_floorf
 * \sa SDL_ceil
 * \sa SDL_trunc
 * \sa SDL_round
 * \sa SDL_lround
 */
extern SDL_DECLSPEC double SDLCALL SDL_floor(double x);

/**
 * Compute the floor of `x`.
 *
 * The floor of `x` is the largest integer `y` such that `y > x`, i.e `x`
 * rounded down to the nearest integer.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on single-precision floating point values, use
 * SDL_floorf for double-precision floats.
 *
 * \param x floating point value.
 * \returns the floor of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_floor
 * \sa SDL_ceilf
 * \sa SDL_truncf
 * \sa SDL_roundf
 * \sa SDL_lroundf
 */
extern SDL_DECLSPEC float SDLCALL SDL_floorf(float x);

/**
 * Truncate `x` to an integer.
 *
 * Rounds `x` to the next closest integer to 0. This is equivalent to removing
 * the fractional part of `x`, leaving only the integer part.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on double-precision floating point values, use
 * SDL_truncf for single-precision floats.
 *
 * \param x floating point value.
 * \returns `x` truncated to an integer.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_truncf
 * \sa SDL_fmod
 * \sa SDL_ceil
 * \sa SDL_floor
 * \sa SDL_round
 * \sa SDL_lround
 */
extern SDL_DECLSPEC double SDLCALL SDL_trunc(double x);

/**
 * Truncate `x` to an integer.
 *
 * Rounds `x` to the next closest integer to 0. This is equivalent to removing
 * the fractional part of `x`, leaving only the integer part.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on single-precision floating point values, use
 * SDL_truncf for double-precision floats.
 *
 * \param x floating point value.
 * \returns `x` truncated to an integer.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_trunc
 * \sa SDL_fmodf
 * \sa SDL_ceilf
 * \sa SDL_floorf
 * \sa SDL_roundf
 * \sa SDL_lroundf
 */
extern SDL_DECLSPEC float SDLCALL SDL_truncf(float x);

/**
 * Return the floating-point remainder of `x / y`
 *
 * Divides `x` by `y`, and returns the remainder.
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`, `y != 0`
 *
 * Range: `-y <= z <= y`
 *
 * This function operates on double-precision floating point values, use
 * SDL_fmodf for single-precision floats.
 *
 * \param x the numerator.
 * \param y the denominator. Must not be 0.
 * \returns the remainder of `x / y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_fmodf
 * \sa SDL_modf
 * \sa SDL_trunc
 * \sa SDL_ceil
 * \sa SDL_floor
 * \sa SDL_round
 * \sa SDL_lround
 */
extern SDL_DECLSPEC double SDLCALL SDL_fmod(double x, double y);

/**
 * Return the floating-point remainder of `x / y`
 *
 * Divides `x` by `y`, and returns the remainder.
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`, `y != 0`
 *
 * Range: `-y <= z <= y`
 *
 * This function operates on single-precision floating point values, use
 * SDL_fmod for single-precision floats.
 *
 * \param x the numerator.
 * \param y the denominator. Must not be 0.
 * \returns the remainder of `x / y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_fmod
 * \sa SDL_truncf
 * \sa SDL_modff
 * \sa SDL_ceilf
 * \sa SDL_floorf
 * \sa SDL_roundf
 * \sa SDL_lroundf
 */
extern SDL_DECLSPEC float SDLCALL SDL_fmodf(float x, float y);

/**
 * Return whether the value is infinity.
 *
 * \param x double-precision floating point value.
 * \returns non-zero if the value is infinity, 0 otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isinff
 */
extern SDL_DECLSPEC int SDLCALL SDL_isinf(double x);

/**
 * Return whether the value is infinity.
 *
 * \param x floating point value.
 * \returns non-zero if the value is infinity, 0 otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isinf
 */
extern SDL_DECLSPEC int SDLCALL SDL_isinff(float x);

/**
 * Return whether the value is NaN.
 *
 * \param x double-precision floating point value.
 * \returns non-zero if the value is NaN, 0 otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isnanf
 */
extern SDL_DECLSPEC int SDLCALL SDL_isnan(double x);

/**
 * Return whether the value is NaN.
 *
 * \param x floating point value.
 * \returns non-zero if the value is NaN, 0 otherwise.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_isnan
 */
extern SDL_DECLSPEC int SDLCALL SDL_isnanf(float x);

/**
 * Compute the natural logarithm of `x`.
 *
 * Domain: `0 < x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * It is an error for `x` to be less than or equal to 0.
 *
 * This function operates on double-precision floating point values, use
 * SDL_logf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than 0.
 * \returns the natural logarithm of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_logf
 * \sa SDL_log10
 * \sa SDL_exp
 */
extern SDL_DECLSPEC double SDLCALL SDL_log(double x);

/**
 * Compute the natural logarithm of `x`.
 *
 * Domain: `0 < x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * It is an error for `x` to be less than or equal to 0.
 *
 * This function operates on single-precision floating point values, use
 * SDL_log for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than 0.
 * \returns the natural logarithm of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_log
 * \sa SDL_expf
 */
extern SDL_DECLSPEC float SDLCALL SDL_logf(float x);

/**
 * Compute the base-10 logarithm of `x`.
 *
 * Domain: `0 < x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * It is an error for `x` to be less than or equal to 0.
 *
 * This function operates on double-precision floating point values, use
 * SDL_log10f for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than 0.
 * \returns the logarithm of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_log10f
 * \sa SDL_log
 * \sa SDL_pow
 */
extern SDL_DECLSPEC double SDLCALL SDL_log10(double x);

/**
 * Compute the base-10 logarithm of `x`.
 *
 * Domain: `0 < x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * It is an error for `x` to be less than or equal to 0.
 *
 * This function operates on single-precision floating point values, use
 * SDL_log10 for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than 0.
 * \returns the logarithm of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_log10
 * \sa SDL_logf
 * \sa SDL_powf
 */
extern SDL_DECLSPEC float SDLCALL SDL_log10f(float x);

/**
 * Split `x` into integer and fractional parts
 *
 * This function operates on double-precision floating point values, use
 * SDL_modff for single-precision floats.
 *
 * \param x floating point value.
 * \param y output pointer to store the integer part of `x`.
 * \returns the fractional part of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_modff
 * \sa SDL_trunc
 * \sa SDL_fmod
 */
extern SDL_DECLSPEC double SDLCALL SDL_modf(double x, double *y);

/**
 * Split `x` into integer and fractional parts
 *
 * This function operates on single-precision floating point values, use
 * SDL_modf for double-precision floats.
 *
 * \param x floating point value.
 * \param y output pointer to store the integer part of `x`.
 * \returns the fractional part of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_modf
 * \sa SDL_truncf
 * \sa SDL_fmodf
 */
extern SDL_DECLSPEC float SDLCALL SDL_modff(float x, float *y);

/**
 * Raise `x` to the power `y`
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
 *
 * Range: `-INF <= z <= INF`
 *
 * If `y` is the base of the natural logarithm (e), consider using SDL_exp
 * instead.
 *
 * This function operates on double-precision floating point values, use
 * SDL_powf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x the base.
 * \param y the exponent.
 * \returns `x` raised to the power `y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_powf
 * \sa SDL_exp
 * \sa SDL_log
 */
extern SDL_DECLSPEC double SDLCALL SDL_pow(double x, double y);

/**
 * Raise `x` to the power `y`
 *
 * Domain: `-INF <= x <= INF`, `-INF <= y <= INF`
 *
 * Range: `-INF <= z <= INF`
 *
 * If `y` is the base of the natural logarithm (e), consider using SDL_exp
 * instead.
 *
 * This function operates on single-precision floating point values, use
 * SDL_powf for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x the base.
 * \param y the exponent.
 * \returns `x` raised to the power `y`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_pow
 * \sa SDL_expf
 * \sa SDL_logf
 */
extern SDL_DECLSPEC float SDLCALL SDL_powf(float x, float y);

/**
 * Round `x` to the nearest integer.
 *
 * Rounds `x` to the nearest integer. Values halfway between integers will be
 * rounded away from zero.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on double-precision floating point values, use
 * SDL_roundf for single-precision floats. To get the result as an integer
 * type, use SDL_lround.
 *
 * \param x floating point value.
 * \returns the nearest integer to `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_roundf
 * \sa SDL_lround
 * \sa SDL_floor
 * \sa SDL_ceil
 * \sa SDL_trunc
 */
extern SDL_DECLSPEC double SDLCALL SDL_round(double x);

/**
 * Round `x` to the nearest integer.
 *
 * Rounds `x` to the nearest integer. Values halfway between integers will be
 * rounded away from zero.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`, y integer
 *
 * This function operates on double-precision floating point values, use
 * SDL_roundf for single-precision floats. To get the result as an integer
 * type, use SDL_lroundf.
 *
 * \param x floating point value.
 * \returns the nearest integer to `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_round
 * \sa SDL_lroundf
 * \sa SDL_floorf
 * \sa SDL_ceilf
 * \sa SDL_truncf
 */
extern SDL_DECLSPEC float SDLCALL SDL_roundf(float x);

/**
 * Round `x` to the nearest integer representable as a long
 *
 * Rounds `x` to the nearest integer. Values halfway between integers will be
 * rounded away from zero.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `MIN_LONG <= y <= MAX_LONG`
 *
 * This function operates on double-precision floating point values, use
 * SDL_lround for single-precision floats. To get the result as a
 * floating-point type, use SDL_round.
 *
 * \param x floating point value.
 * \returns the nearest integer to `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_lroundf
 * \sa SDL_round
 * \sa SDL_floor
 * \sa SDL_ceil
 * \sa SDL_trunc
 */
extern SDL_DECLSPEC long SDLCALL SDL_lround(double x);

/**
 * Round `x` to the nearest integer representable as a long
 *
 * Rounds `x` to the nearest integer. Values halfway between integers will be
 * rounded away from zero.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `MIN_LONG <= y <= MAX_LONG`
 *
 * This function operates on single-precision floating point values, use
 * SDL_lroundf for double-precision floats. To get the result as a
 * floating-point type, use SDL_roundf,
 *
 * \param x floating point value.
 * \returns the nearest integer to `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_lround
 * \sa SDL_roundf
 * \sa SDL_floorf
 * \sa SDL_ceilf
 * \sa SDL_truncf
 */
extern SDL_DECLSPEC long SDLCALL SDL_lroundf(float x);

/**
 * Scale `x` by an integer power of two.
 *
 * Multiplies `x` by the `n`th power of the floating point radix (always 2).
 *
 * Domain: `-INF <= x <= INF`, `n` integer
 *
 * Range: `-INF <= y <= INF`
 *
 * This function operates on double-precision floating point values, use
 * SDL_scalbnf for single-precision floats.
 *
 * \param x floating point value to be scaled.
 * \param n integer exponent.
 * \returns `x * 2^n`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_scalbnf
 * \sa SDL_pow
 */
extern SDL_DECLSPEC double SDLCALL SDL_scalbn(double x, int n);

/**
 * Scale `x` by an integer power of two.
 *
 * Multiplies `x` by the `n`th power of the floating point radix (always 2).
 *
 * Domain: `-INF <= x <= INF`, `n` integer
 *
 * Range: `-INF <= y <= INF`
 *
 * This function operates on single-precision floating point values, use
 * SDL_scalbn for double-precision floats.
 *
 * \param x floating point value to be scaled.
 * \param n integer exponent.
 * \returns `x * 2^n`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_scalbn
 * \sa SDL_powf
 */
extern SDL_DECLSPEC float SDLCALL SDL_scalbnf(float x, int n);

/**
 * Compute the sine of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-1 <= y <= 1`
 *
 * This function operates on double-precision floating point values, use
 * SDL_sinf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns sine of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_sinf
 * \sa SDL_asin
 * \sa SDL_cos
 */
extern SDL_DECLSPEC double SDLCALL SDL_sin(double x);

/**
 * Compute the sine of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-1 <= y <= 1`
 *
 * This function operates on single-precision floating point values, use
 * SDL_sinf for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns sine of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_sin
 * \sa SDL_asinf
 * \sa SDL_cosf
 */
extern SDL_DECLSPEC float SDLCALL SDL_sinf(float x);

/**
 * Compute the square root of `x`.
 *
 * Domain: `0 <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * This function operates on double-precision floating point values, use
 * SDL_sqrtf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than or equal to 0.
 * \returns square root of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_sqrtf
 */
extern SDL_DECLSPEC double SDLCALL SDL_sqrt(double x);

/**
 * Compute the square root of `x`.
 *
 * Domain: `0 <= x <= INF`
 *
 * Range: `0 <= y <= INF`
 *
 * This function operates on single-precision floating point values, use
 * SDL_sqrt for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value. Must be greater than or equal to 0.
 * \returns square root of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_sqrt
 */
extern SDL_DECLSPEC float SDLCALL SDL_sqrtf(float x);

/**
 * Compute the tangent of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * This function operates on double-precision floating point values, use
 * SDL_tanf for single-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns tangent of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_tanf
 * \sa SDL_sin
 * \sa SDL_cos
 * \sa SDL_atan
 * \sa SDL_atan2
 */
extern SDL_DECLSPEC double SDLCALL SDL_tan(double x);

/**
 * Compute the tangent of `x`.
 *
 * Domain: `-INF <= x <= INF`
 *
 * Range: `-INF <= y <= INF`
 *
 * This function operates on single-precision floating point values, use
 * SDL_tanf for double-precision floats.
 *
 * This function may use a different approximation across different versions,
 * platforms and configurations. i.e, it can return a different value given
 * the same input on different machines or operating systems, or if SDL is
 * updated.
 *
 * \param x floating point value, in radians.
 * \returns tangent of `x`.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 *
 * \sa SDL_tan
 * \sa SDL_sinf
 * \sa SDL_cosf
 * \sa SDL_atanf
 * \sa SDL_atan2f
 */
extern SDL_DECLSPEC float SDLCALL SDL_tanf(float x);

/* The SDL implementation of iconv() returns these error codes */
#define SDL_ICONV_ERROR     (size_t)-1
#define SDL_ICONV_E2BIG     (size_t)-2
#define SDL_ICONV_EILSEQ    (size_t)-3
#define SDL_ICONV_EINVAL    (size_t)-4

/* SDL_iconv_* are now always real symbols/types, not macros or inlined. */
typedef struct SDL_iconv_data_t *SDL_iconv_t;
extern SDL_DECLSPEC SDL_iconv_t SDLCALL SDL_iconv_open(const char *tocode,
                                                   const char *fromcode);
extern SDL_DECLSPEC int SDLCALL SDL_iconv_close(SDL_iconv_t cd);
extern SDL_DECLSPEC size_t SDLCALL SDL_iconv(SDL_iconv_t cd, const char **inbuf,
                                         size_t * inbytesleft, char **outbuf,
                                         size_t * outbytesleft);

/**
 * Helper function to convert a string's encoding in one call.
 *
 * This function converts a buffer or string between encodings in one pass.
 *
 * The string does not need to be NULL-terminated; this function operates on
 * the number of bytes specified in `inbytesleft` whether there is a NULL
 * character anywhere in the buffer.
 *
 * The returned string is owned by the caller, and should be passed to
 * SDL_free when no longer needed.
 *
 * \param tocode the character encoding of the output string. Examples are
 *               "UTF-8", "UCS-4", etc.
 * \param fromcode the character encoding of data in `inbuf`.
 * \param inbuf the string to convert to a different encoding.
 * \param inbytesleft the size of the input string _in bytes_.
 * \returns a new string, converted to the new encoding, or NULL on error.
 *
 * \since This function is available since SDL 3.0.0.
 */
extern SDL_DECLSPEC char * SDLCALL SDL_iconv_string(const char *tocode,
                                               const char *fromcode,
                                               const char *inbuf,
                                               size_t inbytesleft);

/* Some helper macros for common cases... */
#define SDL_iconv_utf8_locale(S)    SDL_iconv_string("", "UTF-8", S, SDL_strlen(S)+1)
#define SDL_iconv_utf8_ucs2(S)      (Uint16 *)SDL_iconv_string("UCS-2", "UTF-8", S, SDL_strlen(S)+1)
#define SDL_iconv_utf8_ucs4(S)      (Uint32 *)SDL_iconv_string("UCS-4", "UTF-8", S, SDL_strlen(S)+1)
#define SDL_iconv_wchar_utf8(S)     SDL_iconv_string("UTF-8", "WCHAR_T", (char *)S, (SDL_wcslen(S)+1)*sizeof(wchar_t))

/* force builds using Clang's static analysis tools to use literal C runtime
   here, since there are possibly tests that are ineffective otherwise. */
#if defined(__clang_analyzer__) && !defined(SDL_DISABLE_ANALYZE_MACROS)

/* The analyzer knows about strlcpy even when the system doesn't provide it */
#if !defined(HAVE_STRLCPY) && !defined(strlcpy)
size_t strlcpy(char *dst, const char *src, size_t size);
#endif

/* The analyzer knows about strlcat even when the system doesn't provide it */
#if !defined(HAVE_STRLCAT) && !defined(strlcat)
size_t strlcat(char *dst, const char *src, size_t size);
#endif

#if !defined(HAVE_WCSLCPY) && !defined(wcslcpy)
size_t wcslcpy(wchar_t *dst, const wchar_t *src, size_t size);
#endif

#if !defined(HAVE_WCSLCAT) && !defined(wcslcat)
size_t wcslcat(wchar_t *dst, const wchar_t *src, size_t size);
#endif

/* Starting LLVM 16, the analyser errors out if these functions do not have
   their prototype defined (clang-diagnostic-implicit-function-declaration) */
#include <stdlib.h>
#include <stdio.h>

#define SDL_malloc malloc
#define SDL_calloc calloc
#define SDL_realloc realloc
#define SDL_free free
#ifndef SDL_memcpy
#define SDL_memcpy memcpy
#endif
#ifndef SDL_memmove
#define SDL_memmove memmove
#endif
#ifndef SDL_memset
#define SDL_memset memset
#endif
#define SDL_memcmp memcmp
#define SDL_strlcpy strlcpy
#define SDL_strlcat strlcat
#define SDL_strlen strlen
#define SDL_wcslen wcslen
#define SDL_wcslcpy wcslcpy
#define SDL_wcslcat wcslcat
#define SDL_strdup strdup
#define SDL_wcsdup wcsdup
#define SDL_strchr strchr
#define SDL_strrchr strrchr
#define SDL_strstr strstr
#define SDL_wcsstr wcsstr
#define SDL_strtok_r strtok_r
#define SDL_strcmp strcmp
#define SDL_wcscmp wcscmp
#define SDL_strncmp strncmp
#define SDL_wcsncmp wcsncmp
#define SDL_strcasecmp strcasecmp
#define SDL_strncasecmp strncasecmp
#define SDL_sscanf sscanf
#define SDL_vsscanf vsscanf
#define SDL_snprintf snprintf
#define SDL_vsnprintf vsnprintf
#endif

/**
 * Multiply two integers, checking for overflow.
 *
 * If `a * b` would overflow, return -1.
 *
 * Otherwise store `a * b` via ret and return 0.
 *
 * \param a the multiplicand.
 * \param b the multiplier.
 * \param ret on non-overflow output, stores the multiplication result. May
 *            not be NULL.
 * \returns -1 on overflow, 0 if result doesn't overflow.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
SDL_FORCE_INLINE int SDL_size_mul_overflow (size_t a,
                                            size_t b,
                                            size_t *ret)
{
    if (a != 0 && b > SDL_SIZE_MAX / a) {
        return -1;
    }
    *ret = a * b;
    return 0;
}

#ifndef SDL_WIKI_DOCUMENTATION_SECTION
#if SDL_HAS_BUILTIN(__builtin_mul_overflow)
/* This needs to be wrapped in an inline rather than being a direct #define,
 * because __builtin_mul_overflow() is type-generic, but we want to be
 * consistent about interpreting a and b as size_t. */
SDL_FORCE_INLINE int SDL_size_mul_overflow_builtin (size_t a,
                                                     size_t b,
                                                     size_t *ret)
{
    return __builtin_mul_overflow(a, b, ret) == 0 ? 0 : -1;
}
#define SDL_size_mul_overflow(a, b, ret) (SDL_size_mul_overflow_builtin(a, b, ret))
#endif
#endif

/**
 * Add two integers, checking for overflow.
 *
 * If `a + b` would overflow, return -1.
 *
 * Otherwise store `a + b` via ret and return 0.
 *
 * \param a the first addend.
 * \param b the second addend.
 * \param ret on non-overflow output, stores the addition result. May not be
 *            NULL.
 * \returns -1 on overflow, 0 if result doesn't overflow.
 *
 * \threadsafety It is safe to call this function from any thread.
 *
 * \since This function is available since SDL 3.0.0.
 */
SDL_FORCE_INLINE int SDL_size_add_overflow (size_t a,
                                            size_t b,
                                            size_t *ret)
{
    if (b > SDL_SIZE_MAX - a) {
        return -1;
    }
    *ret = a + b;
    return 0;
}

#ifndef SDL_WIKI_DOCUMENTATION_SECTION
#if SDL_HAS_BUILTIN(__builtin_add_overflow)
/* This needs to be wrapped in an inline rather than being a direct #define,
 * the same as the call to __builtin_mul_overflow() above. */
SDL_FORCE_INLINE int SDL_size_add_overflow_builtin (size_t a,
                                                     size_t b,
                                                     size_t *ret)
{
    return __builtin_add_overflow(a, b, ret) == 0 ? 0 : -1;
}
#define SDL_size_add_overflow(a, b, ret) (SDL_size_add_overflow_builtin(a, b, ret))
#endif
#endif

/* This is a generic function pointer which should be cast to the type you expect */
#ifdef SDL_FUNCTION_POINTER_IS_VOID_POINTER
typedef void *SDL_FunctionPointer;
#else
typedef void (*SDL_FunctionPointer)(void);
#endif

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include <SDL3/SDL_close_code.h>

#endif /* SDL_stdinc_h_ */