llimits.h - external/github.com/lua/lua - Git at Google

 /*
 ** $Id: llimits.h $
 ** Limits, basic types, and some other 'installation-dependent' definitions
 ** See Copyright Notice in lua.h
 */

 #ifndef llimits_h
 #define llimits_h


 #include <limits.h>
 #include <stddef.h>


 #include "lua.h"


 /*
 ** 'l_mem' is a signed integer big enough to count the total memory
 ** used by Lua.  (It is signed due to the use of debt in several
 ** computations.)  Usually, 'ptrdiff_t' should work, but we use 'long'
 ** for 16-bit machines.
 */
 #if defined(LUAI_MEM)		/* { external definitions? */
 typedef LUAI_MEM l_mem;
 typedef LUAI_UMEM lu_mem;
 #elif LUAI_IS32INT	/* }{ */
 typedef ptrdiff_t l_mem;
 typedef size_t lu_mem;
 #else  /* 16-bit ints */	/* }{ */
 typedef long l_mem;
 typedef unsigned long lu_mem;
 #endif				/* } */

 #define MAX_LMEM  \
 	cast(l_mem, (cast(lu_mem, 1) << (sizeof(l_mem) * 8 - 1)) - 1)


 /* chars used as small naturals (so that 'char' is reserved for characters) */
 typedef unsigned char lu_byte;
 typedef signed char ls_byte;


 /* maximum value for size_t */
 #define MAX_SIZET	((size_t)(~(size_t)0))

 /*
 ** Maximum size for strings and userdata visible for Lua; should be
 ** representable as a lua_Integer and as a size_t.
 */
 #define MAX_SIZE	(sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \
 			  : cast_sizet(LUA_MAXINTEGER))

 /*
 ** floor of the log2 of the maximum signed value for integral type 't'.
 ** (That is, maximum 'n' such that '2^n' fits in the given signed type.)
 */
 #define log2maxs(t)	cast_int(sizeof(t) * 8 - 2)


 /*
 ** test whether an unsigned value is a power of 2 (or zero)
 */
 #define ispow2(x)	(((x) & ((x) - 1)) == 0)


 /* number of chars of a literal string without the ending \0 */
 #define LL(x)   (sizeof(x)/sizeof(char) - 1)


 /*
 ** conversion of pointer to unsigned integer: this is for hashing only;
 ** there is no problem if the integer cannot hold the whole pointer
 ** value. (In strict ISO C this may cause undefined behavior, but no
 ** actual machine seems to bother.)
 */
 #if !defined(LUA_USE_C89) && defined(__STDC_VERSION__) && \
     __STDC_VERSION__ >= 199901L
 #include <stdint.h>
 #if defined(UINTPTR_MAX)  /* even in C99 this type is optional */
 #define L_P2I	uintptr_t
 #else  /* no 'intptr'? */
 #define L_P2I	uintmax_t  /* use the largest available integer */
 #endif
 #else  /* C89 option */
 #define L_P2I	size_t
 #endif

 #define point2uint(p)	cast_uint((L_P2I)(p) & UINT_MAX)


 /* types of 'usual argument conversions' for lua_Number and lua_Integer */
 typedef LUAI_UACNUMBER l_uacNumber;
 typedef LUAI_UACINT l_uacInt;


 /*
 ** Internal assertions for in-house debugging
 */
 #if defined LUAI_ASSERT
 #undef NDEBUG
 #include <assert.h>
 #define lua_assert(c)           assert(c)
 #endif

 #if defined(lua_assert)
 #define check_exp(c,e)		(lua_assert(c), (e))
 /* to avoid problems with conditions too long */
 #define lua_longassert(c)	((c) ? (void)0 : lua_assert(0))
 #else
 #define lua_assert(c)		((void)0)
 #define check_exp(c,e)		(e)
 #define lua_longassert(c)	((void)0)
 #endif


 /* macro to avoid warnings about unused variables */
 #if !defined(UNUSED)
 #define UNUSED(x)	((void)(x))
 #endif


 /* type casts (a macro highlights casts in the code) */
 #define cast(t, exp)	((t)(exp))

 #define cast_void(i)	cast(void, (i))
 #define cast_voidp(i)	cast(void *, (i))
 #define cast_num(i)	cast(lua_Number, (i))
 #define cast_int(i)	cast(int, (i))
 #define cast_uint(i)	cast(unsigned int, (i))
 #define cast_ulong(i)	cast(unsigned long, (i))
 #define cast_byte(i)	cast(lu_byte, (i))
 #define cast_uchar(i)	cast(unsigned char, (i))
 #define cast_char(i)	cast(char, (i))
 #define cast_charp(i)	cast(char *, (i))
 #define cast_sizet(i)	cast(size_t, (i))


 /* cast a signed lua_Integer to lua_Unsigned */
 #if !defined(l_castS2U)
 #define l_castS2U(i)	((lua_Unsigned)(i))
 #endif

 /*
 ** cast a lua_Unsigned to a signed lua_Integer; this cast is
 ** not strict ISO C, but two-complement architectures should
 ** work fine.
 */
 #if !defined(l_castU2S)
 #define l_castU2S(i)	((lua_Integer)(i))
 #endif

 /*
 ** cast a size_t to lua_Integer: These casts are always valid for
 ** sizes of Lua objects (see MAX_SIZE)
 */
 #define cast_st2S(sz)	((lua_Integer)(sz))

 /* Cast a ptrdiff_t to size_t, when it is known that the minuend
 ** comes from the subtraend (the base)
 */
 #define ct_diff2sz(df)	((size_t)(df))

 /* ptrdiff_t to lua_Integer */
 #define ct_diff2S(df)	cast_st2S(ct_diff2sz(df))

 /*
 ** Special type equivalent to '(void*)' for functions (to suppress some
 ** warnings when converting function pointers)
 */
 typedef void (*voidf)(void);

 /*
 ** Macro to convert pointer-to-void* to pointer-to-function. This cast
 ** is undefined according to ISO C, but POSIX assumes that it works.
 ** (The '__extension__' in gnu compilers is only to avoid warnings.)
 */
 #if defined(__GNUC__)
 #define cast_func(p) (__extension__ (voidf)(p))
 #else
 #define cast_func(p) ((voidf)(p))
 #endif


 /*
 ** non-return type
 */
 #if !defined(l_noret)

 #if defined(__GNUC__)
 #define l_noret		void __attribute__((noreturn))
 #elif defined(_MSC_VER) && _MSC_VER >= 1200
 #define l_noret		void __declspec(noreturn)
 #else
 #define l_noret		void
 #endif

 #endif


 /*
 ** Inline functions
 */
 #if !defined(LUA_USE_C89)
 #define l_inline	inline
 #elif defined(__GNUC__)
 #define l_inline	__inline__
 #else
 #define l_inline	/* empty */
 #endif

 #define l_sinline	static l_inline


 /*
 ** An unsigned with (at least) 4 bytes
 */
 #if LUAI_IS32INT
 typedef unsigned int l_uint32;
 #else
 typedef unsigned long l_uint32;
 #endif


 /*
 ** The luai_num* macros define the primitive operations over numbers.
 */

 /* floor division (defined as 'floor(a/b)') */
 #if !defined(luai_numidiv)
 #define luai_numidiv(L,a,b)     ((void)L, l_floor(luai_numdiv(L,a,b)))
 #endif

 /* float division */
 #if !defined(luai_numdiv)
 #define luai_numdiv(L,a,b)      ((a)/(b))
 #endif

 /*
 ** modulo: defined as 'a - floor(a/b)*b'; the direct computation
 ** using this definition has several problems with rounding errors,
 ** so it is better to use 'fmod'. 'fmod' gives the result of
 ** 'a - trunc(a/b)*b', and therefore must be corrected when
 ** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a
 ** non-integer negative result: non-integer result is equivalent to
 ** a non-zero remainder 'm'; negative result is equivalent to 'a' and
 ** 'b' with different signs, or 'm' and 'b' with different signs
 ** (as the result 'm' of 'fmod' has the same sign of 'a').
 */
 #if !defined(luai_nummod)
 #define luai_nummod(L,a,b,m)  \
   { (void)L; (m) = l_mathop(fmod)(a,b); \
     if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); }
 #endif

 /* exponentiation */
 #if !defined(luai_numpow)
 #define luai_numpow(L,a,b)  \
   ((void)L, (b == 2) ? (a)*(a) : l_mathop(pow)(a,b))
 #endif

 /* the others are quite standard operations */
 #if !defined(luai_numadd)
 #define luai_numadd(L,a,b)      ((a)+(b))
 #define luai_numsub(L,a,b)      ((a)-(b))
 #define luai_nummul(L,a,b)      ((a)*(b))
 #define luai_numunm(L,a)        (-(a))
 #define luai_numeq(a,b)         ((a)==(b))
 #define luai_numlt(a,b)         ((a)<(b))
 #define luai_numle(a,b)         ((a)<=(b))
 #define luai_numgt(a,b)         ((a)>(b))
 #define luai_numge(a,b)         ((a)>=(b))
 #define luai_numisnan(a)        (!luai_numeq((a), (a)))
 #endif


 /*
 ** {==================================================================
 ** "Abstraction Layer" for basic report of messages and errors
 ** ===================================================================
 */

 /* print a string */
 #if !defined(lua_writestring)
 #define lua_writestring(s,l)   fwrite((s), sizeof(char), (l), stdout)
 #endif

 /* print a newline and flush the output */
 #if !defined(lua_writeline)
 #define lua_writeline()        (lua_writestring("\n", 1), fflush(stdout))
 #endif

 /* print an error message */
 #if !defined(lua_writestringerror)
 #define lua_writestringerror(s,p) \
         (fprintf(stderr, (s), (p)), fflush(stderr))
 #endif

 /* }================================================================== */

 #endif
	/*
	** $Id: llimits.h $
	** Limits, basic types, and some other 'installation-dependent' definitions
	** See Copyright Notice in lua.h
	*/

	#ifndef llimits_h
	#define llimits_h


	#include <limits.h>
	#include <stddef.h>


	#include "lua.h"


	/*
	** 'l_mem' is a signed integer big enough to count the total memory
	** used by Lua. (It is signed due to the use of debt in several
	** computations.) Usually, 'ptrdiff_t' should work, but we use 'long'
	** for 16-bit machines.
	*/
	#if defined(LUAI_MEM) /* { external definitions? */
	typedef LUAI_MEM l_mem;
	typedef LUAI_UMEM lu_mem;
	#elif LUAI_IS32INT /* }{ */
	typedef ptrdiff_t l_mem;
	typedef size_t lu_mem;
	#else /* 16-bit ints / / }{ */
	typedef long l_mem;
	typedef unsigned long lu_mem;
	#endif /* } */

	#define MAX_LMEM \
	cast(l_mem, (cast(lu_mem, 1) << (sizeof(l_mem) * 8 - 1)) - 1)


	/* chars used as small naturals (so that 'char' is reserved for characters) */
	typedef unsigned char lu_byte;
	typedef signed char ls_byte;


	/* maximum value for size_t */
	#define MAX_SIZET ((size_t)(~(size_t)0))

	/*
	** Maximum size for strings and userdata visible for Lua; should be
	** representable as a lua_Integer and as a size_t.
	*/
	#define MAX_SIZE (sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \
	: cast_sizet(LUA_MAXINTEGER))

	/*
	** floor of the log2 of the maximum signed value for integral type 't'.
	** (That is, maximum 'n' such that '2^n' fits in the given signed type.)
	*/
	#define log2maxs(t) cast_int(sizeof(t) * 8 - 2)


	/*
	** test whether an unsigned value is a power of 2 (or zero)
	*/
	#define ispow2(x) (((x) & ((x) - 1)) == 0)


	/* number of chars of a literal string without the ending \0 */
	#define LL(x) (sizeof(x)/sizeof(char) - 1)


	/*
	** conversion of pointer to unsigned integer: this is for hashing only;
	** there is no problem if the integer cannot hold the whole pointer
	** value. (In strict ISO C this may cause undefined behavior, but no
	** actual machine seems to bother.)
	*/
	#if !defined(LUA_USE_C89) && defined(__STDC_VERSION__) && \
	__STDC_VERSION__ >= 199901L
	#include <stdint.h>
	#if defined(UINTPTR_MAX) /* even in C99 this type is optional */
	#define L_P2I uintptr_t
	#else /* no 'intptr'? */
	#define L_P2I uintmax_t /* use the largest available integer */
	#endif
	#else /* C89 option */
	#define L_P2I size_t
	#endif

	#define point2uint(p) cast_uint((L_P2I)(p) & UINT_MAX)



	/* types of 'usual argument conversions' for lua_Number and lua_Integer */
	typedef LUAI_UACNUMBER l_uacNumber;
	typedef LUAI_UACINT l_uacInt;


	/*
	** Internal assertions for in-house debugging
	*/
	#if defined LUAI_ASSERT
	#undef NDEBUG
	#include <assert.h>
	#define lua_assert(c) assert(c)
	#endif

	#if defined(lua_assert)
	#define check_exp(c,e) (lua_assert(c), (e))
	/* to avoid problems with conditions too long */
	#define lua_longassert(c) ((c) ? (void)0 : lua_assert(0))
	#else
	#define lua_assert(c) ((void)0)
	#define check_exp(c,e) (e)
	#define lua_longassert(c) ((void)0)
	#endif


	/* macro to avoid warnings about unused variables */
	#if !defined(UNUSED)
	#define UNUSED(x) ((void)(x))
	#endif


	/* type casts (a macro highlights casts in the code) */
	#define cast(t, exp) ((t)(exp))

	#define cast_void(i) cast(void, (i))
	#define cast_voidp(i) cast(void *, (i))
	#define cast_num(i) cast(lua_Number, (i))
	#define cast_int(i) cast(int, (i))
	#define cast_uint(i) cast(unsigned int, (i))
	#define cast_ulong(i) cast(unsigned long, (i))
	#define cast_byte(i) cast(lu_byte, (i))
	#define cast_uchar(i) cast(unsigned char, (i))
	#define cast_char(i) cast(char, (i))
	#define cast_charp(i) cast(char *, (i))
	#define cast_sizet(i) cast(size_t, (i))


	/* cast a signed lua_Integer to lua_Unsigned */
	#if !defined(l_castS2U)
	#define l_castS2U(i) ((lua_Unsigned)(i))
	#endif

	/*
	** cast a lua_Unsigned to a signed lua_Integer; this cast is
	** not strict ISO C, but two-complement architectures should
	** work fine.
	*/
	#if !defined(l_castU2S)
	#define l_castU2S(i) ((lua_Integer)(i))
	#endif

	/*
	** cast a size_t to lua_Integer: These casts are always valid for
	** sizes of Lua objects (see MAX_SIZE)
	*/
	#define cast_st2S(sz) ((lua_Integer)(sz))

	/* Cast a ptrdiff_t to size_t, when it is known that the minuend
	** comes from the subtraend (the base)
	*/
	#define ct_diff2sz(df) ((size_t)(df))

	/* ptrdiff_t to lua_Integer */
	#define ct_diff2S(df) cast_st2S(ct_diff2sz(df))

	/*
	** Special type equivalent to '(void*)' for functions (to suppress some
	** warnings when converting function pointers)
	*/
	typedef void (*voidf)(void);

	/*
	** Macro to convert pointer-to-void* to pointer-to-function. This cast
	** is undefined according to ISO C, but POSIX assumes that it works.
	** (The '__extension__' in gnu compilers is only to avoid warnings.)
	*/
	#if defined(__GNUC__)
	#define cast_func(p) (__extension__ (voidf)(p))
	#else
	#define cast_func(p) ((voidf)(p))
	#endif



	/*
	** non-return type
	*/
	#if !defined(l_noret)

	#if defined(__GNUC__)
	#define l_noret void __attribute__((noreturn))
	#elif defined(_MSC_VER) && _MSC_VER >= 1200
	#define l_noret void __declspec(noreturn)
	#else
	#define l_noret void
	#endif

	#endif


	/*
	** Inline functions
	*/
	#if !defined(LUA_USE_C89)
	#define l_inline inline
	#elif defined(__GNUC__)
	#define l_inline __inline__
	#else
	#define l_inline /* empty */
	#endif

	#define l_sinline static l_inline


	/*
	** An unsigned with (at least) 4 bytes
	*/
	#if LUAI_IS32INT
	typedef unsigned int l_uint32;
	#else
	typedef unsigned long l_uint32;
	#endif


	/*
	** The luai_num* macros define the primitive operations over numbers.
	*/

	/* floor division (defined as 'floor(a/b)') */
	#if !defined(luai_numidiv)
	#define luai_numidiv(L,a,b) ((void)L, l_floor(luai_numdiv(L,a,b)))
	#endif

	/* float division */
	#if !defined(luai_numdiv)
	#define luai_numdiv(L,a,b) ((a)/(b))
	#endif

	/*
	** modulo: defined as 'a - floor(a/b)*b'; the direct computation
	** using this definition has several problems with rounding errors,
	** so it is better to use 'fmod'. 'fmod' gives the result of
	** 'a - trunc(a/b)*b', and therefore must be corrected when
	** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a
	** non-integer negative result: non-integer result is equivalent to
	** a non-zero remainder 'm'; negative result is equivalent to 'a' and
	** 'b' with different signs, or 'm' and 'b' with different signs
	** (as the result 'm' of 'fmod' has the same sign of 'a').
	*/
	#if !defined(luai_nummod)
	#define luai_nummod(L,a,b,m) \
	{ (void)L; (m) = l_mathop(fmod)(a,b); \
	if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); }
	#endif

	/* exponentiation */
	#if !defined(luai_numpow)
	#define luai_numpow(L,a,b) \
	((void)L, (b == 2) ? (a)*(a) : l_mathop(pow)(a,b))
	#endif

	/* the others are quite standard operations */
	#if !defined(luai_numadd)
	#define luai_numadd(L,a,b) ((a)+(b))
	#define luai_numsub(L,a,b) ((a)-(b))
	#define luai_nummul(L,a,b) ((a)*(b))
	#define luai_numunm(L,a) (-(a))
	#define luai_numeq(a,b) ((a)==(b))
	#define luai_numlt(a,b) ((a)<(b))
	#define luai_numle(a,b) ((a)<=(b))
	#define luai_numgt(a,b) ((a)>(b))
	#define luai_numge(a,b) ((a)>=(b))
	#define luai_numisnan(a) (!luai_numeq((a), (a)))
	#endif


	/*
	** {==================================================================
	** "Abstraction Layer" for basic report of messages and errors
	** ===================================================================
	*/

	/* print a string */
	#if !defined(lua_writestring)
	#define lua_writestring(s,l) fwrite((s), sizeof(char), (l), stdout)
	#endif

	/* print a newline and flush the output */
	#if !defined(lua_writeline)
	#define lua_writeline() (lua_writestring("\n", 1), fflush(stdout))
	#endif

	/* print an error message */
	#if !defined(lua_writestringerror)
	#define lua_writestringerror(s,p) \
	(fprintf(stderr, (s), (p)), fflush(stderr))
	#endif

	/* }================================================================== */

	#endif