ba8b5c17 |
1 | /* |
2 | ** $Id: lobject.c,v 2.58 2013/02/20 14:08:56 roberto Exp $ |
3 | ** Some generic functions over Lua objects |
4 | ** See Copyright Notice in lua.h |
5 | */ |
6 | |
7 | #include <stdarg.h> |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <string.h> |
11 | |
12 | #define lobject_c |
13 | #define LUA_CORE |
14 | |
15 | #include "lua.h" |
16 | |
17 | #include "lctype.h" |
18 | #include "ldebug.h" |
19 | #include "ldo.h" |
20 | #include "lmem.h" |
21 | #include "lobject.h" |
22 | #include "lstate.h" |
23 | #include "lstring.h" |
24 | #include "lvm.h" |
25 | |
26 | |
27 | |
28 | LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT}; |
29 | |
30 | |
31 | /* |
32 | ** converts an integer to a "floating point byte", represented as |
33 | ** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if |
34 | ** eeeee != 0 and (xxx) otherwise. |
35 | */ |
36 | int luaO_int2fb (unsigned int x) { |
37 | int e = 0; /* exponent */ |
38 | if (x < 8) return x; |
39 | while (x >= 0x10) { |
40 | x = (x+1) >> 1; |
41 | e++; |
42 | } |
43 | return ((e+1) << 3) | (cast_int(x) - 8); |
44 | } |
45 | |
46 | |
47 | /* converts back */ |
48 | int luaO_fb2int (int x) { |
49 | int e = (x >> 3) & 0x1f; |
50 | if (e == 0) return x; |
51 | else return ((x & 7) + 8) << (e - 1); |
52 | } |
53 | |
54 | |
55 | int luaO_ceillog2 (unsigned int x) { |
56 | static const lu_byte log_2[256] = { |
57 | 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, |
58 | 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, |
59 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, |
60 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, |
61 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
62 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
63 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
64 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8 |
65 | }; |
66 | int l = 0; |
67 | x--; |
68 | while (x >= 256) { l += 8; x >>= 8; } |
69 | return l + log_2[x]; |
70 | } |
71 | |
72 | |
73 | lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) { |
74 | switch (op) { |
75 | case LUA_OPADD: return luai_numadd(NULL, v1, v2); |
76 | case LUA_OPSUB: return luai_numsub(NULL, v1, v2); |
77 | case LUA_OPMUL: return luai_nummul(NULL, v1, v2); |
78 | case LUA_OPDIV: return luai_numdiv(NULL, v1, v2); |
79 | case LUA_OPMOD: return luai_nummod(NULL, v1, v2); |
80 | case LUA_OPPOW: return luai_numpow(NULL, v1, v2); |
81 | case LUA_OPUNM: return luai_numunm(NULL, v1); |
82 | default: lua_assert(0); return 0; |
83 | } |
84 | } |
85 | |
86 | |
87 | int luaO_hexavalue (int c) { |
88 | if (lisdigit(c)) return c - '0'; |
89 | else return ltolower(c) - 'a' + 10; |
90 | } |
91 | |
92 | |
93 | #if !defined(lua_strx2number) |
94 | |
95 | #include <math.h> |
96 | |
97 | |
98 | static int isneg (const char **s) { |
99 | if (**s == '-') { (*s)++; return 1; } |
100 | else if (**s == '+') (*s)++; |
101 | return 0; |
102 | } |
103 | |
104 | |
105 | static lua_Number readhexa (const char **s, lua_Number r, int *count) { |
106 | for (; lisxdigit(cast_uchar(**s)); (*s)++) { /* read integer part */ |
107 | r = (r * cast_num(16.0)) + cast_num(luaO_hexavalue(cast_uchar(**s))); |
108 | (*count)++; |
109 | } |
110 | return r; |
111 | } |
112 | |
113 | |
114 | /* |
115 | ** convert an hexadecimal numeric string to a number, following |
116 | ** C99 specification for 'strtod' |
117 | */ |
118 | static lua_Number lua_strx2number (const char *s, char **endptr) { |
119 | lua_Number r = 0.0; |
120 | int e = 0, i = 0; |
121 | int neg = 0; /* 1 if number is negative */ |
122 | *endptr = cast(char *, s); /* nothing is valid yet */ |
123 | while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */ |
124 | neg = isneg(&s); /* check signal */ |
125 | if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X'))) /* check '0x' */ |
126 | return 0.0; /* invalid format (no '0x') */ |
127 | s += 2; /* skip '0x' */ |
128 | r = readhexa(&s, r, &i); /* read integer part */ |
129 | if (*s == '.') { |
130 | s++; /* skip dot */ |
131 | r = readhexa(&s, r, &e); /* read fractional part */ |
132 | } |
133 | if (i == 0 && e == 0) |
134 | return 0.0; /* invalid format (no digit) */ |
135 | e *= -4; /* each fractional digit divides value by 2^-4 */ |
136 | *endptr = cast(char *, s); /* valid up to here */ |
137 | if (*s == 'p' || *s == 'P') { /* exponent part? */ |
138 | int exp1 = 0; |
139 | int neg1; |
140 | s++; /* skip 'p' */ |
141 | neg1 = isneg(&s); /* signal */ |
142 | if (!lisdigit(cast_uchar(*s))) |
143 | goto ret; /* must have at least one digit */ |
144 | while (lisdigit(cast_uchar(*s))) /* read exponent */ |
145 | exp1 = exp1 * 10 + *(s++) - '0'; |
146 | if (neg1) exp1 = -exp1; |
147 | e += exp1; |
148 | } |
149 | *endptr = cast(char *, s); /* valid up to here */ |
150 | ret: |
151 | if (neg) r = -r; |
152 | return l_mathop(ldexp)(r, e); |
153 | } |
154 | |
155 | #endif |
156 | |
157 | |
158 | int luaO_str2d (const char *s, size_t len, lua_Number *result) { |
159 | char *endptr; |
160 | if (strpbrk(s, "nN")) /* reject 'inf' and 'nan' */ |
161 | return 0; |
162 | else if (strpbrk(s, "xX")) /* hexa? */ |
163 | *result = lua_strx2number(s, &endptr); |
164 | else |
165 | *result = lua_str2number(s, &endptr); |
166 | if (endptr == s) return 0; /* nothing recognized */ |
167 | while (lisspace(cast_uchar(*endptr))) endptr++; |
168 | return (endptr == s + len); /* OK if no trailing characters */ |
169 | } |
170 | |
171 | |
172 | |
173 | static void pushstr (lua_State *L, const char *str, size_t l) { |
174 | setsvalue2s(L, L->top++, luaS_newlstr(L, str, l)); |
175 | } |
176 | |
177 | |
178 | /* this function handles only `%d', `%c', %f, %p, and `%s' formats */ |
179 | const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) { |
180 | int n = 0; |
181 | for (;;) { |
182 | const char *e = strchr(fmt, '%'); |
183 | if (e == NULL) break; |
184 | luaD_checkstack(L, 2); /* fmt + item */ |
185 | pushstr(L, fmt, e - fmt); |
186 | switch (*(e+1)) { |
187 | case 's': { |
188 | const char *s = va_arg(argp, char *); |
189 | if (s == NULL) s = "(null)"; |
190 | pushstr(L, s, strlen(s)); |
191 | break; |
192 | } |
193 | case 'c': { |
194 | char buff; |
195 | buff = cast(char, va_arg(argp, int)); |
196 | pushstr(L, &buff, 1); |
197 | break; |
198 | } |
199 | case 'd': { |
200 | setnvalue(L->top++, cast_num(va_arg(argp, int))); |
201 | break; |
202 | } |
203 | case 'f': { |
204 | setnvalue(L->top++, cast_num(va_arg(argp, l_uacNumber))); |
205 | break; |
206 | } |
207 | case 'p': { |
208 | char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */ |
209 | int l = sprintf(buff, "%p", va_arg(argp, void *)); |
210 | pushstr(L, buff, l); |
211 | break; |
212 | } |
213 | case '%': { |
214 | pushstr(L, "%", 1); |
215 | break; |
216 | } |
217 | default: { |
218 | luaG_runerror(L, |
219 | "invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"), |
220 | *(e + 1)); |
221 | } |
222 | } |
223 | n += 2; |
224 | fmt = e+2; |
225 | } |
226 | luaD_checkstack(L, 1); |
227 | pushstr(L, fmt, strlen(fmt)); |
228 | if (n > 0) luaV_concat(L, n + 1); |
229 | return svalue(L->top - 1); |
230 | } |
231 | |
232 | |
233 | const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) { |
234 | const char *msg; |
235 | va_list argp; |
236 | va_start(argp, fmt); |
237 | msg = luaO_pushvfstring(L, fmt, argp); |
238 | va_end(argp); |
239 | return msg; |
240 | } |
241 | |
242 | |
243 | /* number of chars of a literal string without the ending \0 */ |
244 | #define LL(x) (sizeof(x)/sizeof(char) - 1) |
245 | |
246 | #define RETS "..." |
247 | #define PRE "[string \"" |
248 | #define POS "\"]" |
249 | |
250 | #define addstr(a,b,l) ( memcpy(a,b,(l) * sizeof(char)), a += (l) ) |
251 | |
252 | void luaO_chunkid (char *out, const char *source, size_t bufflen) { |
253 | size_t l = strlen(source); |
254 | if (*source == '=') { /* 'literal' source */ |
255 | if (l <= bufflen) /* small enough? */ |
256 | memcpy(out, source + 1, l * sizeof(char)); |
257 | else { /* truncate it */ |
258 | addstr(out, source + 1, bufflen - 1); |
259 | *out = '\0'; |
260 | } |
261 | } |
262 | else if (*source == '@') { /* file name */ |
263 | if (l <= bufflen) /* small enough? */ |
264 | memcpy(out, source + 1, l * sizeof(char)); |
265 | else { /* add '...' before rest of name */ |
266 | addstr(out, RETS, LL(RETS)); |
267 | bufflen -= LL(RETS); |
268 | memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char)); |
269 | } |
270 | } |
271 | else { /* string; format as [string "source"] */ |
272 | const char *nl = strchr(source, '\n'); /* find first new line (if any) */ |
273 | addstr(out, PRE, LL(PRE)); /* add prefix */ |
274 | bufflen -= LL(PRE RETS POS) + 1; /* save space for prefix+suffix+'\0' */ |
275 | if (l < bufflen && nl == NULL) { /* small one-line source? */ |
276 | addstr(out, source, l); /* keep it */ |
277 | } |
278 | else { |
279 | if (nl != NULL) l = nl - source; /* stop at first newline */ |
280 | if (l > bufflen) l = bufflen; |
281 | addstr(out, source, l); |
282 | addstr(out, RETS, LL(RETS)); |
283 | } |
284 | memcpy(out, POS, (LL(POS) + 1) * sizeof(char)); |
285 | } |
286 | } |
287 | |