The Battle for Wesnoth  1.15.12+dev
llimits.h
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1 /*
2 ** $Id: llimits.h $
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 <limits.h>
12 #include <stddef.h>
13 
14 
15 #include "lua.h"
16 
17 
18 /*
19 ** 'lu_mem' and 'l_mem' are unsigned/signed integers big enough to count
20 ** the total memory used by Lua (in bytes). Usually, 'size_t' and
21 ** 'ptrdiff_t' should work, but we use 'long' for 16-bit machines.
22 */
23 #if defined(LUAI_MEM) /* { external definitions? */
24 typedef LUAI_UMEM lu_mem;
25 typedef LUAI_MEM l_mem;
26 #elif LUAI_IS32INT /* }{ */
27 typedef size_t lu_mem;
28 typedef ptrdiff_t l_mem;
29 #else /* 16-bit ints */ /* }{ */
30 typedef unsigned long lu_mem;
31 typedef long l_mem;
32 #endif /* } */
33 
34 
35 /* chars used as small naturals (so that 'char' is reserved for characters) */
36 typedef unsigned char lu_byte;
37 typedef signed char ls_byte;
38 
39 
40 /* maximum value for size_t */
41 #define MAX_SIZET ((size_t)(~(size_t)0))
42 
43 /* maximum size visible for Lua (must be representable in a lua_Integer) */
44 #define MAX_SIZE (sizeof(size_t) < sizeof(lua_Integer) ? MAX_SIZET \
45  : (size_t)(LUA_MAXINTEGER))
46 
47 
48 #define MAX_LUMEM ((lu_mem)(~(lu_mem)0))
49 
50 #define MAX_LMEM ((l_mem)(MAX_LUMEM >> 1))
51 
52 
53 #define MAX_INT INT_MAX /* maximum value of an int */
54 
55 
56 /*
57 ** floor of the log2 of the maximum signed value for integral type 't'.
58 ** (That is, maximum 'n' such that '2^n' fits in the given signed type.)
59 */
60 #define log2maxs(t) (sizeof(t) * 8 - 2)
61 
62 
63 /*
64 ** test whether an unsigned value is a power of 2 (or zero)
65 */
66 #define ispow2(x) (((x) & ((x) - 1)) == 0)
67 
68 
69 /* number of chars of a literal string without the ending \0 */
70 #define LL(x) (sizeof(x)/sizeof(char) - 1)
71 
72 
73 /*
74 ** conversion of pointer to unsigned integer:
75 ** this is for hashing only; there is no problem if the integer
76 ** cannot hold the whole pointer value
77 */
78 #define point2uint(p) ((unsigned int)((size_t)(p) & UINT_MAX))
79 
80 
81 
82 /* types of 'usual argument conversions' for lua_Number and lua_Integer */
85 
86 
87 /*
88 ** Internal assertions for in-house debugging
89 */
90 #if defined LUAI_ASSERT
91 #undef NDEBUG
92 #include <assert.h>
93 #define lua_assert(c) assert(c)
94 #endif
95 
96 #if defined(lua_assert)
97 #define check_exp(c,e) (lua_assert(c), (e))
98 /* to avoid problems with conditions too long */
99 #define lua_longassert(c) ((c) ? (void)0 : lua_assert(0))
100 #else
101 #define lua_assert(c) ((void)0)
102 #define check_exp(c,e) (e)
103 #define lua_longassert(c) ((void)0)
104 #endif
105 
106 /*
107 ** assertion for checking API calls
108 */
109 #if !defined(luai_apicheck)
110 #define luai_apicheck(l,e) ((void)l, lua_assert(e))
111 #endif
112 
113 #define api_check(l,e,msg) luai_apicheck(l,(e) && msg)
114 
115 
116 /* macro to avoid warnings about unused variables */
117 #if !defined(UNUSED)
118 #define UNUSED(x) ((void)(x))
119 #endif
120 
121 
122 /* type casts (a macro highlights casts in the code) */
123 #define cast(t, exp) ((t)(exp))
124 
125 #define cast_void(i) cast(void, (i))
126 #define cast_voidp(i) cast(void *, (i))
127 #define cast_num(i) cast(lua_Number, (i))
128 #define cast_int(i) cast(int, (i))
129 #define cast_uint(i) cast(unsigned int, (i))
130 #define cast_byte(i) cast(lu_byte, (i))
131 #define cast_uchar(i) cast(unsigned char, (i))
132 #define cast_char(i) cast(char, (i))
133 #define cast_charp(i) cast(char *, (i))
134 #define cast_sizet(i) cast(size_t, (i))
135 
136 
137 /* cast a signed lua_Integer to lua_Unsigned */
138 #if !defined(l_castS2U)
139 #define l_castS2U(i) ((lua_Unsigned)(i))
140 #endif
141 
142 /*
143 ** cast a lua_Unsigned to a signed lua_Integer; this cast is
144 ** not strict ISO C, but two-complement architectures should
145 ** work fine.
146 */
147 #if !defined(l_castU2S)
148 #define l_castU2S(i) ((lua_Integer)(i))
149 #endif
150 
151 
152 /*
153 ** macros to improve jump prediction (used mainly for error handling)
154 */
155 #if !defined(likely)
156 
157 #if defined(__GNUC__)
158 #define likely(x) (__builtin_expect(((x) != 0), 1))
159 #define unlikely(x) (__builtin_expect(((x) != 0), 0))
160 #else
161 #define likely(x) (x)
162 #define unlikely(x) (x)
163 #endif
164 
165 #endif
166 
167 
168 /*
169 ** non-return type
170 */
171 #if !defined(l_noret)
172 
173 #if defined(__GNUC__)
174 #define l_noret void __attribute__((noreturn))
175 #elif defined(_MSC_VER) && _MSC_VER >= 1200
176 #define l_noret void __declspec(noreturn)
177 #else
178 #define l_noret void
179 #endif
180 
181 #endif
182 
183 
184 /*
185 ** type for virtual-machine instructions;
186 ** must be an unsigned with (at least) 4 bytes (see details in lopcodes.h)
187 */
188 #if LUAI_IS32INT
189 typedef unsigned int l_uint32;
190 #else
191 typedef unsigned long l_uint32;
192 #endif
193 
195 
196 
197 
198 /*
199 ** Maximum length for short strings, that is, strings that are
200 ** internalized. (Cannot be smaller than reserved words or tags for
201 ** metamethods, as these strings must be internalized;
202 ** #("function") = 8, #("__newindex") = 10.)
203 */
204 #if !defined(LUAI_MAXSHORTLEN)
205 #define LUAI_MAXSHORTLEN 40
206 #endif
207 
208 
209 /*
210 ** Initial size for the string table (must be power of 2).
211 ** The Lua core alone registers ~50 strings (reserved words +
212 ** metaevent keys + a few others). Libraries would typically add
213 ** a few dozens more.
214 */
215 #if !defined(MINSTRTABSIZE)
216 #define MINSTRTABSIZE 128
217 #endif
218 
219 
220 /*
221 ** Size of cache for strings in the API. 'N' is the number of
222 ** sets (better be a prime) and "M" is the size of each set (M == 1
223 ** makes a direct cache.)
224 */
225 #if !defined(STRCACHE_N)
226 #define STRCACHE_N 53
227 #define STRCACHE_M 2
228 #endif
229 
230 
231 /* minimum size for string buffer */
232 #if !defined(LUA_MINBUFFER)
233 #define LUA_MINBUFFER 32
234 #endif
235 
236 
237 /*
238 ** Maximum depth for nested C calls, syntactical nested non-terminals,
239 ** and other features implemented through recursion in C. (Value must
240 ** fit in a 16-bit unsigned integer. It must also be compatible with
241 ** the size of the C stack.)
242 */
243 #if !defined(LUAI_MAXCCALLS)
244 #define LUAI_MAXCCALLS 200
245 #endif
246 
247 
248 /*
249 ** macros that are executed whenever program enters the Lua core
250 ** ('lua_lock') and leaves the core ('lua_unlock')
251 */
252 #if !defined(lua_lock)
253 #define lua_lock(L) ((void) 0)
254 #define lua_unlock(L) ((void) 0)
255 #endif
256 
257 /*
258 ** macro executed during Lua functions at points where the
259 ** function can yield.
260 */
261 #if !defined(luai_threadyield)
262 #define luai_threadyield(L) {lua_unlock(L); lua_lock(L);}
263 #endif
264 
265 
266 /*
267 ** these macros allow user-specific actions when a thread is
268 ** created/deleted/resumed/yielded.
269 */
270 #if !defined(luai_userstateopen)
271 #define luai_userstateopen(L) ((void)L)
272 #endif
273 
274 #if !defined(luai_userstateclose)
275 #define luai_userstateclose(L) ((void)L)
276 #endif
277 
278 #if !defined(luai_userstatethread)
279 #define luai_userstatethread(L,L1) ((void)L)
280 #endif
281 
282 #if !defined(luai_userstatefree)
283 #define luai_userstatefree(L,L1) ((void)L)
284 #endif
285 
286 #if !defined(luai_userstateresume)
287 #define luai_userstateresume(L,n) ((void)L)
288 #endif
289 
290 #if !defined(luai_userstateyield)
291 #define luai_userstateyield(L,n) ((void)L)
292 #endif
293 
294 
295 
296 /*
297 ** The luai_num* macros define the primitive operations over numbers.
298 */
299 
300 /* floor division (defined as 'floor(a/b)') */
301 #if !defined(luai_numidiv)
302 #define luai_numidiv(L,a,b) ((void)L, l_floor(luai_numdiv(L,a,b)))
303 #endif
304 
305 /* float division */
306 #if !defined(luai_numdiv)
307 #define luai_numdiv(L,a,b) ((a)/(b))
308 #endif
309 
310 /*
311 ** modulo: defined as 'a - floor(a/b)*b'; the direct computation
312 ** using this definition has several problems with rounding errors,
313 ** so it is better to use 'fmod'. 'fmod' gives the result of
314 ** 'a - trunc(a/b)*b', and therefore must be corrected when
315 ** 'trunc(a/b) ~= floor(a/b)'. That happens when the division has a
316 ** non-integer negative result: non-integer result is equivalent to
317 ** a non-zero remainder 'm'; negative result is equivalent to 'a' and
318 ** 'b' with different signs, or 'm' and 'b' with different signs
319 ** (as the result 'm' of 'fmod' has the same sign of 'a').
320 */
321 #if !defined(luai_nummod)
322 #define luai_nummod(L,a,b,m) \
323  { (void)L; (m) = l_mathop(fmod)(a,b); \
324  if (((m) > 0) ? (b) < 0 : ((m) < 0 && (b) > 0)) (m) += (b); }
325 #endif
326 
327 /* exponentiation */
328 #if !defined(luai_numpow)
329 #define luai_numpow(L,a,b) \
330  ((void)L, (b == 2) ? (a)*(a) : l_mathop(pow)(a,b))
331 #endif
332 
333 /* the others are quite standard operations */
334 #if !defined(luai_numadd)
335 #define luai_numadd(L,a,b) ((a)+(b))
336 #define luai_numsub(L,a,b) ((a)-(b))
337 #define luai_nummul(L,a,b) ((a)*(b))
338 #define luai_numunm(L,a) (-(a))
339 #define luai_numeq(a,b) ((a)==(b))
340 #define luai_numlt(a,b) ((a)<(b))
341 #define luai_numle(a,b) ((a)<=(b))
342 #define luai_numgt(a,b) ((a)>(b))
343 #define luai_numge(a,b) ((a)>=(b))
344 #define luai_numisnan(a) (!luai_numeq((a), (a)))
345 #endif
346 
347 
348 
349 
350 
351 /*
352 ** macro to control inclusion of some hard tests on stack reallocation
353 */
354 #if !defined(HARDSTACKTESTS)
355 #define condmovestack(L,pre,pos) ((void)0)
356 #else
357 /* realloc stack keeping its size */
358 #define condmovestack(L,pre,pos) \
359  { int sz_ = stacksize(L); pre; luaD_reallocstack((L), sz_, 0); pos; }
360 #endif
361 
362 #if !defined(HARDMEMTESTS)
363 #define condchangemem(L,pre,pos) ((void)0)
364 #else
365 #define condchangemem(L,pre,pos) \
366  { if (G(L)->gcrunning) { pre; luaC_fullgc(L, 0); pos; } }
367 #endif
368 
369 #endif
signed char ls_byte
Definition: llimits.h:37
#define LUAI_UACNUMBER
Definition: luaconf.h:458
LUAI_UACINT l_uacInt
Definition: llimits.h:84
unsigned long lu_mem
Definition: llimits.h:30
long l_mem
Definition: llimits.h:31
unsigned char lu_byte
Definition: llimits.h:36
unsigned long l_uint32
Definition: llimits.h:191
#define LUAI_UACINT
Definition: luaconf.h:496
l_uint32 Instruction
Definition: llimits.h:194
LUAI_UACNUMBER l_uacNumber
Definition: llimits.h:83