2 ** $Id: llimits.h,v 1.103.1.1 2013/04/12 18:48:47 roberto Exp $
3 ** Limits, basic types, and some other `installation-dependent' definitions
4 ** See Copyright Notice in lua.h
11 #include <sys/zfs_context.h>
16 typedef unsigned LUA_INT32 lu_int32;
18 typedef LUAI_UMEM lu_mem;
20 typedef LUAI_MEM l_mem;
24 /* chars used as small naturals (so that `char' is reserved for characters) */
25 typedef unsigned char lu_byte;
28 #define MAX_SIZET ((size_t)(~(size_t)0)-2)
30 #define MAX_LUMEM ((lu_mem)(~(lu_mem)0)-2)
32 #define MAX_LMEM ((l_mem) ((MAX_LUMEM >> 1) - 2))
35 #define MAX_INT (INT_MAX-2) /* maximum value of an int (-2 for safety) */
38 ** conversion of pointer to integer
39 ** this is for hashing only; there is no problem if the integer
40 ** cannot hold the whole pointer value
42 #define IntPoint(p) ((unsigned int)(lu_mem)(p))
46 /* type to ensure maximum alignment */
47 #if !defined(LUAI_USER_ALIGNMENT_T)
48 #define LUAI_USER_ALIGNMENT_T union { double u; void *s; long l; }
51 typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;
54 /* result of a `usual argument conversion' over lua_Number */
55 typedef LUAI_UACNUMBER l_uacNumber;
58 /* internal assertions for in-house debugging */
59 #if defined(lua_assert)
60 #define check_exp(c,e) (lua_assert(c), (e))
61 /* to avoid problems with conditions too long */
62 #define lua_longassert(c) { if (!(c)) lua_assert(0); }
64 #define lua_assert(c) ((void)0)
65 #define check_exp(c,e) (e)
66 #define lua_longassert(c) ((void)0)
70 ** assertion for checking API calls
72 #if !defined(luai_apicheck)
74 #if defined(LUA_USE_APICHECK)
76 #define luai_apicheck(L,e) assert(e)
78 #define luai_apicheck(L,e) lua_assert(e)
83 #define api_check(l,e,msg) luai_apicheck(l,(e) && msg)
87 #define UNUSED(x) ((void)(x)) /* to avoid warnings */
91 #define cast(t, exp) ((t)(exp))
93 #define cast_byte(i) cast(lu_byte, (i))
94 #define cast_num(i) cast(lua_Number, (i))
95 #define cast_int(i) cast(int, (i))
96 #define cast_uchar(i) cast(unsigned char, (i))
102 #if defined(__GNUC__)
103 #define l_noret void __attribute__((noreturn))
104 #elif defined(_MSC_VER)
105 #define l_noret void __declspec(noreturn)
113 ** maximum depth for nested C calls and syntactical nested non-terminals
114 ** in a program. (Value must fit in an unsigned short int.)
116 ** Note: On amd64 platform, the limit has been measured to be 45. We set
117 ** the maximum lower to give a margin for changing the amount of stack
118 ** used by various functions involved in parsing and executing code.
120 #if !defined(LUAI_MAXCCALLS)
121 #define LUAI_MAXCCALLS 20
125 ** maximum number of upvalues in a closure (both C and Lua). (Value
126 ** must fit in an unsigned char.)
128 #define MAXUPVAL UCHAR_MAX
132 ** type for virtual-machine instructions
133 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
135 typedef lu_int32 Instruction;
139 /* maximum stack for a Lua function */
144 /* minimum size for the string table (must be power of 2) */
145 #if !defined(MINSTRTABSIZE)
146 #define MINSTRTABSIZE 32
150 /* minimum size for string buffer */
151 #if !defined(LUA_MINBUFFER)
152 #define LUA_MINBUFFER 32
156 #if !defined(lua_lock)
157 #define lua_lock(L) ((void) 0)
158 #define lua_unlock(L) ((void) 0)
161 #if !defined(luai_threadyield)
162 #define luai_threadyield(L) {lua_unlock(L); lua_lock(L);}
167 ** these macros allow user-specific actions on threads when you defined
168 ** LUAI_EXTRASPACE and need to do something extra when a thread is
169 ** created/deleted/resumed/yielded.
171 #if !defined(luai_userstateopen)
172 #define luai_userstateopen(L) ((void)L)
175 #if !defined(luai_userstateclose)
176 #define luai_userstateclose(L) ((void)L)
179 #if !defined(luai_userstatethread)
180 #define luai_userstatethread(L,L1) ((void)L)
183 #if !defined(luai_userstatefree)
184 #define luai_userstatefree(L,L1) ((void)L)
187 #if !defined(luai_userstateresume)
188 #define luai_userstateresume(L,n) ((void)L)
191 #if !defined(luai_userstateyield)
192 #define luai_userstateyield(L,n) ((void)L)
196 ** lua_number2int is a macro to convert lua_Number to int.
197 ** lua_number2integer is a macro to convert lua_Number to lua_Integer.
198 ** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned.
199 ** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number.
200 ** luai_hashnum is a macro to hash a lua_Number value into an integer.
201 ** The hash must be deterministic and give reasonable values for
202 ** both small and large values (outside the range of integers).
205 #if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK) /* { */
206 /* trick with Microsoft assembler for X86 */
208 #define lua_number2int(i,n) __asm {__asm fld n __asm fistp i}
209 #define lua_number2integer(i,n) lua_number2int(i, n)
210 #define lua_number2unsigned(i,n) \
211 {__int64 l; __asm {__asm fld n __asm fistp l} i = (unsigned int)l;}
214 #elif defined(LUA_IEEE754TRICK) /* }{ */
215 /* the next trick should work on any machine using IEEE754 with
218 union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
220 #if !defined(LUA_IEEEENDIAN) /* { */
221 #define LUAI_EXTRAIEEE \
222 static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};
223 #define LUA_IEEEENDIANLOC (ieeeendian.l_p[1] == 33)
225 #define LUA_IEEEENDIANLOC LUA_IEEEENDIAN
226 #define LUAI_EXTRAIEEE /* empty */
229 #define lua_number2int32(i,n,t) \
231 volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
232 (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }
234 #define luai_hashnum(i,n) \
235 { volatile union luai_Cast u; u.l_d = (n) + 1.0; /* avoid -0 */ \
236 (i) = u.l_p[0]; (i) += u.l_p[1]; } /* add double bits for his hash */
238 #define lua_number2int(i,n) lua_number2int32(i, n, int)
239 #define lua_number2unsigned(i,n) lua_number2int32(i, n, lua_Unsigned)
241 /* the trick can be expanded to lua_Integer when it is a 32-bit value */
242 #if defined(LUA_IEEELL)
243 #define lua_number2integer(i,n) lua_number2int32(i, n, lua_Integer)
249 /* the following definitions always work, but may be slow */
251 #if !defined(lua_number2int)
252 #define lua_number2int(i,n) ((i)=(int)(n))
255 #if !defined(lua_number2integer)
256 #define lua_number2integer(i,n) ((i)=(lua_Integer)(n))
259 #if !defined(lua_number2unsigned) /* { */
260 /* the following definition assures proper modulo behavior */
261 #if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT)
263 #define SUPUNSIGNED ((lua_Number)(~(lua_Unsigned)0) + 1)
264 #define lua_number2unsigned(i,n) \
265 ((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))
267 #define lua_number2unsigned(i,n) ((i)=(lua_Unsigned)(n))
272 #if !defined(lua_unsigned2number)
273 /* on several machines, coercion from unsigned to double is slow,
274 so it may be worth to avoid */
275 #define lua_unsigned2number(u) \
276 (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))
281 #if defined(ltable_c) && !defined(luai_hashnum)
283 extern int lcompat_hashnum(int64_t);
285 #define luai_hashnum(i,n) (i = lcompat_hashnum(n))
292 ** macro to control inclusion of some hard tests on stack reallocation
294 #if !defined(HARDSTACKTESTS)
295 #define condmovestack(L) ((void)0)
297 /* realloc stack keeping its size */
298 #define condmovestack(L) luaD_reallocstack((L), (L)->stacksize)
301 #if !defined(HARDMEMTESTS)
302 #define condchangemem(L) condmovestack(L)
304 #define condchangemem(L) \
305 ((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))