xref: /illumos-gate/usr/src/uts/common/fs/zfs/lua/llimits.h (revision dfc11533)
1 /*
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
5 */
6 
7 #ifndef llimits_h
8 #define llimits_h
9 
10 
11 #include <sys/zfs_context.h>
12 
13 #include "lua.h"
14 
15 
16 typedef unsigned LUA_INT32 lu_int32;
17 
18 typedef LUAI_UMEM lu_mem;
19 
20 typedef LUAI_MEM l_mem;
21 
22 
23 
24 /* chars used as small naturals (so that `char' is reserved for characters) */
25 typedef unsigned char lu_byte;
26 
27 
28 #define MAX_SIZET	((size_t)(~(size_t)0)-2)
29 
30 #define MAX_LUMEM	((lu_mem)(~(lu_mem)0)-2)
31 
32 #define MAX_LMEM	((l_mem) ((MAX_LUMEM >> 1) - 2))
33 
34 
35 #define MAX_INT (INT_MAX-2)  /* maximum value of an int (-2 for safety) */
36 
37 /*
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
41 */
42 #define IntPoint(p)  ((unsigned int)(lu_mem)(p))
43 
44 
45 
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; }
49 #endif
50 
51 typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;
52 
53 
54 /* result of a `usual argument conversion' over lua_Number */
55 typedef LUAI_UACNUMBER l_uacNumber;
56 
57 
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); }
63 #else
64 #define lua_assert(c)		((void)0)
65 #define check_exp(c,e)		(e)
66 #define lua_longassert(c)	((void)0)
67 #endif
68 
69 /*
70 ** assertion for checking API calls
71 */
72 #if !defined(luai_apicheck)
73 
74 #if defined(LUA_USE_APICHECK)
75 #include <assert.h>
76 #define luai_apicheck(L,e)	assert(e)
77 #else
78 #define luai_apicheck(L,e)	lua_assert(e)
79 #endif
80 
81 #endif
82 
83 #define api_check(l,e,msg)	luai_apicheck(l,(e) && msg)
84 
85 
86 #if !defined(UNUSED)
87 #define UNUSED(x)	((void)(x))	/* to avoid warnings */
88 #endif
89 
90 
91 #define cast(t, exp)	((t)(exp))
92 
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))
97 
98 
99 /*
100 ** non-return type
101 */
102 #if defined(__GNUC__)
103 #define l_noret		void __attribute__((noreturn))
104 #elif defined(_MSC_VER)
105 #define l_noret		void __declspec(noreturn)
106 #else
107 #define l_noret		void
108 #endif
109 
110 
111 
112 /*
113 ** maximum depth for nested C calls and syntactical nested non-terminals
114 ** in a program. (Value must fit in an unsigned short int.)
115 **
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.
119 */
120 #if !defined(LUAI_MAXCCALLS)
121 #define LUAI_MAXCCALLS		20
122 #endif
123 
124 /*
125 ** maximum number of upvalues in a closure (both C and Lua). (Value
126 ** must fit in an unsigned char.)
127 */
128 #define MAXUPVAL	UCHAR_MAX
129 
130 
131 /*
132 ** type for virtual-machine instructions
133 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
134 */
135 typedef lu_int32 Instruction;
136 
137 
138 
139 /* maximum stack for a Lua function */
140 #define MAXSTACK	250
141 
142 
143 
144 /* minimum size for the string table (must be power of 2) */
145 #if !defined(MINSTRTABSIZE)
146 #define MINSTRTABSIZE	32
147 #endif
148 
149 
150 /* minimum size for string buffer */
151 #if !defined(LUA_MINBUFFER)
152 #define LUA_MINBUFFER	32
153 #endif
154 
155 
156 #if !defined(lua_lock)
157 #define lua_lock(L)     ((void) 0)
158 #define lua_unlock(L)   ((void) 0)
159 #endif
160 
161 #if !defined(luai_threadyield)
162 #define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);}
163 #endif
164 
165 
166 /*
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.
170 */
171 #if !defined(luai_userstateopen)
172 #define luai_userstateopen(L)		((void)L)
173 #endif
174 
175 #if !defined(luai_userstateclose)
176 #define luai_userstateclose(L)		((void)L)
177 #endif
178 
179 #if !defined(luai_userstatethread)
180 #define luai_userstatethread(L,L1)	((void)L)
181 #endif
182 
183 #if !defined(luai_userstatefree)
184 #define luai_userstatefree(L,L1)	((void)L)
185 #endif
186 
187 #if !defined(luai_userstateresume)
188 #define luai_userstateresume(L,n)       ((void)L)
189 #endif
190 
191 #if !defined(luai_userstateyield)
192 #define luai_userstateyield(L,n)        ((void)L)
193 #endif
194 
195 /*
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).
203 */
204 
205 #if defined(MS_ASMTRICK) || defined(LUA_MSASMTRICK)	/* { */
206 /* trick with Microsoft assembler for X86 */
207 
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;}
212 
213 
214 #elif defined(LUA_IEEE754TRICK)		/* }{ */
215 /* the next trick should work on any machine using IEEE754 with
216    a 32-bit int type */
217 
218 union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
219 
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)
224 #else
225 #define LUA_IEEEENDIANLOC	LUA_IEEEENDIAN
226 #define LUAI_EXTRAIEEE		/* empty */
227 #endif				/* } */
228 
229 #define lua_number2int32(i,n,t) \
230   { LUAI_EXTRAIEEE \
231     volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
232     (i) = (t)u.l_p[LUA_IEEEENDIANLOC]; }
233 
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 */
237 
238 #define lua_number2int(i,n)		lua_number2int32(i, n, int)
239 #define lua_number2unsigned(i,n)	lua_number2int32(i, n, lua_Unsigned)
240 
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)
244 #endif
245 
246 #endif				/* } */
247 
248 
249 /* the following definitions always work, but may be slow */
250 
251 #if !defined(lua_number2int)
252 #define lua_number2int(i,n)	((i)=(int)(n))
253 #endif
254 
255 #if !defined(lua_number2integer)
256 #define lua_number2integer(i,n)	((i)=(lua_Integer)(n))
257 #endif
258 
259 #if !defined(lua_number2unsigned)	/* { */
260 /* the following definition assures proper modulo behavior */
261 #if defined(LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_FLOAT)
262 #include <math.h>
263 #define SUPUNSIGNED	((lua_Number)(~(lua_Unsigned)0) + 1)
264 #define lua_number2unsigned(i,n)  \
265 	((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))
266 #else
267 #define lua_number2unsigned(i,n)	((i)=(lua_Unsigned)(n))
268 #endif
269 #endif				/* } */
270 
271 
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))
277 #endif
278 
279 
280 
281 #if defined(ltable_c) && !defined(luai_hashnum)
282 
283 extern int lcompat_hashnum(int64_t);
284 
285 #define luai_hashnum(i,n) (i = lcompat_hashnum(n))
286 
287 #endif
288 
289 
290 
291 /*
292 ** macro to control inclusion of some hard tests on stack reallocation
293 */
294 #if !defined(HARDSTACKTESTS)
295 #define condmovestack(L)	((void)0)
296 #else
297 /* realloc stack keeping its size */
298 #define condmovestack(L)	luaD_reallocstack((L), (L)->stacksize)
299 #endif
300 
301 #if !defined(HARDMEMTESTS)
302 #define condchangemem(L)	condmovestack(L)
303 #else
304 #define condchangemem(L)  \
305 	((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))
306 #endif
307 
308 #endif
309