| 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 | |