1 /* 2 ** $Id: lobject.c,v 2.58.1.1 2013/04/12 18:48:47 roberto Exp $ 3 ** Some generic functions over Lua objects 4 ** See Copyright Notice in lua.h 5 */ 6 7 #define lobject_c 8 #define LUA_CORE 9 10 #include <sys/lua/lua.h> 11 12 #include "lctype.h" 13 #include "ldebug.h" 14 #include "ldo.h" 15 #include "lmem.h" 16 #include "lobject.h" 17 #include "lstate.h" 18 #include "lstring.h" 19 #include "lvm.h" 20 21 22 23 LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT}; 24 25 26 /* 27 ** converts an integer to a "floating point byte", represented as 28 ** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if 29 ** eeeee != 0 and (xxx) otherwise. 30 */ 31 int luaO_int2fb (unsigned int x) { 32 int e = 0; /* exponent */ 33 if (x < 8) return x; 34 while (x >= 0x10) { 35 x = (x+1) >> 1; 36 e++; 37 } 38 return ((e+1) << 3) | (cast_int(x) - 8); 39 } 40 41 42 /* converts back */ 43 int luaO_fb2int (int x) { 44 int e = (x >> 3) & 0x1f; 45 if (e == 0) return x; 46 else return ((x & 7) + 8) << (e - 1); 47 } 48 49 50 int luaO_ceillog2 (unsigned int x) { 51 static const lu_byte log_2[256] = { 52 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, 53 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, 54 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, 55 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, 56 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, 57 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, 58 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, 59 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 60 }; 61 int l = 0; 62 x--; 63 while (x >= 256) { l += 8; x >>= 8; } 64 return l + log_2[x]; 65 } 66 67 68 lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) { 69 switch (op) { 70 case LUA_OPADD: return luai_numadd(NULL, v1, v2); 71 case LUA_OPSUB: return luai_numsub(NULL, v1, v2); 72 case LUA_OPMUL: return luai_nummul(NULL, v1, v2); 73 case LUA_OPDIV: return luai_numdiv(NULL, v1, v2); 74 case LUA_OPMOD: return luai_nummod(NULL, v1, v2); 75 case LUA_OPPOW: return luai_numpow(NULL, v1, v2); 76 case LUA_OPUNM: return luai_numunm(NULL, v1); 77 default: lua_assert(0); return 0; 78 } 79 } 80 81 82 int luaO_hexavalue (int c) { 83 if (lisdigit(c)) return c - '0'; 84 else return ltolower(c) - 'a' + 10; 85 } 86 87 88 #if !defined(lua_strx2number) 89 90 91 92 static int isneg (const char **s) { 93 if (**s == '-') { (*s)++; return 1; } 94 else if (**s == '+') (*s)++; 95 return 0; 96 } 97 98 99 static lua_Number readhexa (const char **s, lua_Number r, int *count) { 100 for (; lisxdigit(cast_uchar(**s)); (*s)++) { /* read integer part */ 101 r = (r * cast_num(16.0)) + cast_num(luaO_hexavalue(cast_uchar(**s))); 102 (*count)++; 103 } 104 return r; 105 } 106 107 108 /* 109 ** convert an hexadecimal numeric string to a number, following 110 ** C99 specification for 'strtod' 111 */ 112 static lua_Number lua_strx2number (const char *s, char **endptr) { 113 lua_Number r = 0.0; 114 int e = 0, i = 0; 115 int neg = 0; /* 1 if number is negative */ 116 *endptr = cast(char *, s); /* nothing is valid yet */ 117 while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */ 118 neg = isneg(&s); /* check signal */ 119 if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X'))) /* check '0x' */ 120 return 0.0; /* invalid format (no '0x') */ 121 s += 2; /* skip '0x' */ 122 r = readhexa(&s, r, &i); /* read integer part */ 123 if (*s == '.') { 124 s++; /* skip dot */ 125 r = readhexa(&s, r, &e); /* read fractional part */ 126 } 127 if (i == 0 && e == 0) 128 return 0.0; /* invalid format (no digit) */ 129 e *= -4; /* each fractional digit divides value by 2^-4 */ 130 *endptr = cast(char *, s); /* valid up to here */ 131 if (*s == 'p' || *s == 'P') { /* exponent part? */ 132 int exp1 = 0; 133 int neg1; 134 s++; /* skip 'p' */ 135 neg1 = isneg(&s); /* signal */ 136 if (!lisdigit(cast_uchar(*s))) 137 goto ret; /* must have at least one digit */ 138 while (lisdigit(cast_uchar(*s))) /* read exponent */ 139 exp1 = exp1 * 10 + *(s++) - '0'; 140 if (neg1) exp1 = -exp1; 141 e += exp1; 142 } 143 *endptr = cast(char *, s); /* valid up to here */ 144 ret: 145 if (neg) r = -r; 146 return ((e >= 0) ? (r * (1ULL << e)) : (r / (1ULL << -e))); 147 } 148 149 #endif 150 151 152 int luaO_str2d (const char *s, size_t len, lua_Number *result) { 153 char *endptr; 154 if (strpbrk(s, "nN")) /* reject 'inf' and 'nan' */ 155 return 0; 156 else if (strpbrk(s, "xX")) /* hexa? */ 157 *result = lua_strx2number(s, &endptr); 158 else 159 *result = lua_str2number(s, &endptr); 160 if (endptr == s) return 0; /* nothing recognized */ 161 while (lisspace(cast_uchar(*endptr))) endptr++; 162 return (endptr == s + len); /* OK if no trailing characters */ 163 } 164 165 166 167 static void pushstr (lua_State *L, const char *str, size_t l) { 168 setsvalue2s(L, L->top++, luaS_newlstr(L, str, l)); 169 } 170 171 172 /* this function handles only `%d', `%c', %f, %p, and `%s' formats */ 173 const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) { 174 int n = 0; 175 for (;;) { 176 const char *e = strchr(fmt, '%'); 177 if (e == NULL) break; 178 luaD_checkstack(L, 2); /* fmt + item */ 179 pushstr(L, fmt, e - fmt); 180 switch (*(e+1)) { 181 case 's': { 182 const char *s = va_arg(argp, char *); 183 if (s == NULL) s = "(null)"; 184 pushstr(L, s, strlen(s)); 185 break; 186 } 187 case 'c': { 188 char buff; 189 buff = cast(char, va_arg(argp, int)); 190 pushstr(L, &buff, 1); 191 break; 192 } 193 case 'd': { 194 setnvalue(L->top++, cast_num(va_arg(argp, int))); 195 break; 196 } 197 case 'f': { 198 setnvalue(L->top++, cast_num(va_arg(argp, l_uacNumber))); 199 break; 200 } 201 case 'p': { 202 char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */ 203 int l = lcompat_sprintf(buff, sizeof(buff), "%p", va_arg(argp, void *)); 204 pushstr(L, buff, l); 205 break; 206 } 207 case '%': { 208 pushstr(L, "%", 1); 209 break; 210 } 211 default: { 212 luaG_runerror(L, 213 "invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"), 214 *(e + 1)); 215 } 216 } 217 n += 2; 218 fmt = e+2; 219 } 220 luaD_checkstack(L, 1); 221 pushstr(L, fmt, strlen(fmt)); 222 if (n > 0) luaV_concat(L, n + 1); 223 return svalue(L->top - 1); 224 } 225 226 227 const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) { 228 const char *msg; 229 va_list argp; 230 va_start(argp, fmt); 231 msg = luaO_pushvfstring(L, fmt, argp); 232 va_end(argp); 233 return msg; 234 } 235 236 237 /* number of chars of a literal string without the ending \0 */ 238 #define LL(x) (sizeof(x)/sizeof(char) - 1) 239 240 #define RETS "..." 241 #define PRE "[string \"" 242 #define POS "\"]" 243 244 #define addstr(a,b,l) ( memcpy(a,b,(l) * sizeof(char)), a += (l) ) 245 246 void luaO_chunkid (char *out, const char *source, size_t bufflen) { 247 size_t l = strlen(source); 248 if (*source == '=') { /* 'literal' source */ 249 if (l <= bufflen) /* small enough? */ 250 memcpy(out, source + 1, l * sizeof(char)); 251 else { /* truncate it */ 252 addstr(out, source + 1, bufflen - 1); 253 *out = '\0'; 254 } 255 } 256 else if (*source == '@') { /* file name */ 257 if (l <= bufflen) /* small enough? */ 258 memcpy(out, source + 1, l * sizeof(char)); 259 else { /* add '...' before rest of name */ 260 addstr(out, RETS, LL(RETS)); 261 bufflen -= LL(RETS); 262 memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char)); 263 } 264 } 265 else { /* string; format as [string "source"] */ 266 const char *nl = strchr(source, '\n'); /* find first new line (if any) */ 267 addstr(out, PRE, LL(PRE)); /* add prefix */ 268 bufflen -= LL(PRE RETS POS) + 1; /* save space for prefix+suffix+'\0' */ 269 if (l < bufflen && nl == NULL) { /* small one-line source? */ 270 addstr(out, source, l); /* keep it */ 271 } 272 else { 273 if (nl != NULL) l = nl - source; /* stop at first newline */ 274 if (l > bufflen) l = bufflen; 275 addstr(out, source, l); 276 addstr(out, RETS, LL(RETS)); 277 } 278 memcpy(out, POS, (LL(POS) + 1) * sizeof(char)); 279 } 280 } 281