ceph/src/civetweb/src/third_party/lua-5.3.3/src/lobject.c

   1 /*
   2 ** $Id: lobject.c,v 2.111 2016/05/20 14:07:48 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 "lprefix.h"
  11
  12
  13 #include <locale.h>
  14 #include <math.h>
  15 #include <stdarg.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19
  20 #include "lua.h"
  21
  22 #include "lctype.h"
  23 #include "ldebug.h"
  24 #include "ldo.h"
  25 #include "lmem.h"
  26 #include "lobject.h"
  27 #include "lstate.h"
  28 #include "lstring.h"
  29 #include "lvm.h"
  30
  31
  32
  33 LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT};
  34
  35
  36 /*
  37 ** converts an integer to a "floating point byte", represented as
  38 ** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if
  39 ** eeeee != 0 and (xxx) otherwise.
  40 */
  41 int luaO_int2fb (unsigned int x) {
  42   int e = 0;  /* exponent */
  43   if (x < 8) return x;
  44   while (x >= (8 << 4)) {  /* coarse steps */
  45     x = (x + 0xf) >> 4;  /* x = ceil(x / 16) */
  46     e += 4;
  47   }
  48   while (x >= (8 << 1)) {  /* fine steps */
  49     x = (x + 1) >> 1;  /* x = ceil(x / 2) */
  50     e++;
  51   }
  52   return ((e+1) << 3) | (cast_int(x) - 8);
  53 }
  54
  55
  56 /* converts back */
  57 int luaO_fb2int (int x) {
  58   return (x < 8) ? x : ((x & 7) + 8) << ((x >> 3) - 1);
  59 }
  60
  61
  62 /*
  63 ** Computes ceil(log2(x))
  64 */
  65 int luaO_ceillog2 (unsigned int x) {
  66   static const lu_byte log_2[256] = {  /* log_2[i] = ceil(log2(i - 1)) */
  67     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,
  68     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,
  69     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,
  70     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,
  71     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,
  72     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,
  73     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,
  74     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
  75   };
  76   int l = 0;
  77   x--;
  78   while (x >= 256) { l += 8; x >>= 8; }
  79   return l + log_2[x];
  80 }
  81
  82
  83 static lua_Integer intarith (lua_State *L, int op, lua_Integer v1,
  84                                                    lua_Integer v2) {
  85   switch (op) {
  86     case LUA_OPADD: return intop(+, v1, v2);
  87     case LUA_OPSUB:return intop(-, v1, v2);
  88     case LUA_OPMUL:return intop(*, v1, v2);
  89     case LUA_OPMOD: return luaV_mod(L, v1, v2);
  90     case LUA_OPIDIV: return luaV_div(L, v1, v2);
  91     case LUA_OPBAND: return intop(&, v1, v2);
  92     case LUA_OPBOR: return intop(|, v1, v2);
  93     case LUA_OPBXOR: return intop(^, v1, v2);
  94     case LUA_OPSHL: return luaV_shiftl(v1, v2);
  95     case LUA_OPSHR: return luaV_shiftl(v1, -v2);
  96     case LUA_OPUNM: return intop(-, 0, v1);
  97     case LUA_OPBNOT: return intop(^, ~l_castS2U(0), v1);
  98     default: lua_assert(0); return 0;
  99   }
 100 }
 101
 102
 103 static lua_Number numarith (lua_State *L, int op, lua_Number v1,
 104                                                   lua_Number v2) {
 105   switch (op) {
 106     case LUA_OPADD: return luai_numadd(L, v1, v2);
 107     case LUA_OPSUB: return luai_numsub(L, v1, v2);
 108     case LUA_OPMUL: return luai_nummul(L, v1, v2);
 109     case LUA_OPDIV: return luai_numdiv(L, v1, v2);
 110     case LUA_OPPOW: return luai_numpow(L, v1, v2);
 111     case LUA_OPIDIV: return luai_numidiv(L, v1, v2);
 112     case LUA_OPUNM: return luai_numunm(L, v1);
 113     case LUA_OPMOD: {
 114       lua_Number m;
 115       luai_nummod(L, v1, v2, m);
 116       return m;
 117     }
 118     default: lua_assert(0); return 0;
 119   }
 120 }
 121
 122
 123 void luaO_arith (lua_State *L, int op, const TValue *p1, const TValue *p2,
 124                  TValue *res) {
 125   switch (op) {
 126     case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR:
 127     case LUA_OPSHL: case LUA_OPSHR:
 128     case LUA_OPBNOT: {  /* operate only on integers */
 129       lua_Integer i1; lua_Integer i2;
 130       if (tointeger(p1, &i1) && tointeger(p2, &i2)) {
 131         setivalue(res, intarith(L, op, i1, i2));
 132         return;
 133       }
 134       else break;  /* go to the end */
 135     }
 136     case LUA_OPDIV: case LUA_OPPOW: {  /* operate only on floats */
 137       lua_Number n1; lua_Number n2;
 138       if (tonumber(p1, &n1) && tonumber(p2, &n2)) {
 139         setfltvalue(res, numarith(L, op, n1, n2));
 140         return;
 141       }
 142       else break;  /* go to the end */
 143     }
 144     default: {  /* other operations */
 145       lua_Number n1; lua_Number n2;
 146       if (ttisinteger(p1) && ttisinteger(p2)) {
 147         setivalue(res, intarith(L, op, ivalue(p1), ivalue(p2)));
 148         return;
 149       }
 150       else if (tonumber(p1, &n1) && tonumber(p2, &n2)) {
 151         setfltvalue(res, numarith(L, op, n1, n2));
 152         return;
 153       }
 154       else break;  /* go to the end */
 155     }
 156   }
 157   /* could not perform raw operation; try metamethod */
 158   lua_assert(L != NULL);  /* should not fail when folding (compile time) */
 159   luaT_trybinTM(L, p1, p2, res, cast(TMS, (op - LUA_OPADD) + TM_ADD));
 160 }
 161
 162
 163 int luaO_hexavalue (int c) {
 164   if (lisdigit(c)) return c - '0';
 165   else return (ltolower(c) - 'a') + 10;
 166 }
 167
 168
 169 static int isneg (const char **s) {
 170   if (**s == '-') { (*s)++; return 1; }
 171   else if (**s == '+') (*s)++;
 172   return 0;
 173 }
 174
 175
 176
 177 /*
 178 ** {==================================================================
 179 ** Lua's implementation for 'lua_strx2number'
 180 ** ===================================================================
 181 */
 182
 183 #if !defined(lua_strx2number)
 184
 185 /* maximum number of significant digits to read (to avoid overflows
 186    even with single floats) */
 187 #define MAXSIGDIG       30
 188
 189 /*
 190 ** convert an hexadecimal numeric string to a number, following
 191 ** C99 specification for 'strtod'
 192 */
 193 static lua_Number lua_strx2number (const char *s, char **endptr) {
 194   int dot = lua_getlocaledecpoint();
 195   lua_Number r = 0.0;  /* result (accumulator) */
 196   int sigdig = 0;  /* number of significant digits */
 197   int nosigdig = 0;  /* number of non-significant digits */
 198   int e = 0;  /* exponent correction */
 199   int neg;  /* 1 if number is negative */
 200   int hasdot = 0;  /* true after seen a dot */
 201   *endptr = cast(char *, s);  /* nothing is valid yet */
 202   while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
 203   neg = isneg(&s);  /* check signal */
 204   if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X')))  /* check '0x' */
 205     return 0.0;  /* invalid format (no '0x') */
 206   for (s += 2; ; s++) {  /* skip '0x' and read numeral */
 207     if (*s == dot) {
 208       if (hasdot) break;  /* second dot? stop loop */
 209       else hasdot = 1;
 210     }
 211     else if (lisxdigit(cast_uchar(*s))) {
 212       if (sigdig == 0 && *s == '0')  /* non-significant digit (zero)? */
 213         nosigdig++;
 214       else if (++sigdig <= MAXSIGDIG)  /* can read it without overflow? */
 215           r = (r * cast_num(16.0)) + luaO_hexavalue(*s);
 216       else e++; /* too many digits; ignore, but still count for exponent */
 217       if (hasdot) e--;  /* decimal digit? correct exponent */
 218     }
 219     else break;  /* neither a dot nor a digit */
 220   }
 221   if (nosigdig + sigdig == 0)  /* no digits? */
 222     return 0.0;  /* invalid format */
 223   *endptr = cast(char *, s);  /* valid up to here */
 224   e *= 4;  /* each digit multiplies/divides value by 2^4 */
 225   if (*s == 'p' || *s == 'P') {  /* exponent part? */
 226     int exp1 = 0;  /* exponent value */
 227     int neg1;  /* exponent signal */
 228     s++;  /* skip 'p' */
 229     neg1 = isneg(&s);  /* signal */
 230     if (!lisdigit(cast_uchar(*s)))
 231       return 0.0;  /* invalid; must have at least one digit */
 232     while (lisdigit(cast_uchar(*s)))  /* read exponent */
 233       exp1 = exp1 * 10 + *(s++) - '0';
 234     if (neg1) exp1 = -exp1;
 235     e += exp1;
 236     *endptr = cast(char *, s);  /* valid up to here */
 237   }
 238   if (neg) r = -r;
 239   return l_mathop(ldexp)(r, e);
 240 }
 241
 242 #endif
 243 /* }====================================================== */
 244
 245
 246 /* maximum length of a numeral */
 247 #if !defined (L_MAXLENNUM)
 248 #define L_MAXLENNUM     200
 249 #endif
 250
 251 static const char *l_str2dloc (const char *s, lua_Number *result, int mode) {
 252   char *endptr;
 253   *result = (mode == 'x') ? lua_strx2number(s, &endptr)  /* try to convert */
 254                           : lua_str2number(s, &endptr);
 255   if (endptr == s) return NULL;  /* nothing recognized? */
 256   while (lisspace(cast_uchar(*endptr))) endptr++;  /* skip trailing spaces */
 257   return (*endptr == '\0') ? endptr : NULL;  /* OK if no trailing characters */
 258 }
 259
 260
 261 /*
 262 ** Convert string 's' to a Lua number (put in 'result'). Return NULL
 263 ** on fail or the address of the ending '\0' on success.
 264 ** 'pmode' points to (and 'mode' contains) special things in the string:
 265 ** - 'x'/'X' means an hexadecimal numeral
 266 ** - 'n'/'N' means 'inf' or 'nan' (which should be rejected)
 267 ** - '.' just optimizes the search for the common case (nothing special)
 268 ** This function accepts both the current locale or a dot as the radix
 269 ** mark. If the convertion fails, it may mean number has a dot but
 270 ** locale accepts something else. In that case, the code copies 's'
 271 ** to a buffer (because 's' is read-only), changes the dot to the
 272 ** current locale radix mark, and tries to convert again.
 273 */
 274 static const char *l_str2d (const char *s, lua_Number *result) {
 275   const char *endptr;
 276   const char *pmode = strpbrk(s, ".xXnN");
 277   int mode = pmode ? ltolower(cast_uchar(*pmode)) : 0;
 278   if (mode == 'n')  /* reject 'inf' and 'nan' */
 279     return NULL;
 280   endptr = l_str2dloc(s, result, mode);  /* try to convert */
 281   if (endptr == NULL) {  /* failed? may be a different locale */
 282     char buff[L_MAXLENNUM + 1];
 283     char *pdot = strchr(s, '.');
 284     if (strlen(s) > L_MAXLENNUM || pdot == NULL)
 285       return NULL;  /* string too long or no dot; fail */
 286     strcpy(buff, s);  /* copy string to buffer */
 287     buff[pdot - s] = lua_getlocaledecpoint();  /* correct decimal point */
 288     endptr = l_str2dloc(buff, result, mode);  /* try again */
 289     if (endptr != NULL)
 290       endptr = s + (endptr - buff);  /* make relative to 's' */
 291   }
 292   return endptr;
 293 }
 294
 295
 296 #define MAXBY10         cast(lua_Unsigned, LUA_MAXINTEGER / 10)
 297 #define MAXLASTD        cast_int(LUA_MAXINTEGER % 10)
 298
 299 static const char *l_str2int (const char *s, lua_Integer *result) {
 300   lua_Unsigned a = 0;
 301   int empty = 1;
 302   int neg;
 303   while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
 304   neg = isneg(&s);
 305   if (s[0] == '0' &&
 306       (s[1] == 'x' || s[1] == 'X')) {  /* hex? */
 307     s += 2;  /* skip '0x' */
 308     for (; lisxdigit(cast_uchar(*s)); s++) {
 309       a = a * 16 + luaO_hexavalue(*s);
 310       empty = 0;
 311     }
 312   }
 313   else {  /* decimal */
 314     for (; lisdigit(cast_uchar(*s)); s++) {
 315       int d = *s - '0';
 316       if (a >= MAXBY10 && (a > MAXBY10 || d > MAXLASTD + neg))  /* overflow? */
 317         return NULL;  /* do not accept it (as integer) */
 318       a = a * 10 + d;
 319       empty = 0;
 320     }
 321   }
 322   while (lisspace(cast_uchar(*s))) s++;  /* skip trailing spaces */
 323   if (empty || *s != '\0') return NULL;  /* something wrong in the numeral */
 324   else {
 325     *result = l_castU2S((neg) ? 0u - a : a);
 326     return s;
 327   }
 328 }
 329
 330
 331 size_t luaO_str2num (const char *s, TValue *o) {
 332   lua_Integer i; lua_Number n;
 333   const char *e;
 334   if ((e = l_str2int(s, &i)) != NULL) {  /* try as an integer */
 335     setivalue(o, i);
 336   }
 337   else if ((e = l_str2d(s, &n)) != NULL) {  /* else try as a float */
 338     setfltvalue(o, n);
 339   }
 340   else
 341     return 0;  /* conversion failed */
 342   return (e - s) + 1;  /* success; return string size */
 343 }
 344
 345
 346 int luaO_utf8esc (char *buff, unsigned long x) {
 347   int n = 1;  /* number of bytes put in buffer (backwards) */
 348   lua_assert(x <= 0x10FFFF);
 349   if (x < 0x80)  /* ascii? */
 350     buff[UTF8BUFFSZ - 1] = cast(char, x);
 351   else {  /* need continuation bytes */
 352     unsigned int mfb = 0x3f;  /* maximum that fits in first byte */
 353     do {  /* add continuation bytes */
 354       buff[UTF8BUFFSZ - (n++)] = cast(char, 0x80 | (x & 0x3f));
 355       x >>= 6;  /* remove added bits */
 356       mfb >>= 1;  /* now there is one less bit available in first byte */
 357     } while (x > mfb);  /* still needs continuation byte? */
 358     buff[UTF8BUFFSZ - n] = cast(char, (~mfb << 1) | x);  /* add first byte */
 359   }
 360   return n;
 361 }
 362
 363
 364 /* maximum length of the conversion of a number to a string */
 365 #define MAXNUMBER2STR   50
 366
 367
 368 /*
 369 ** Convert a number object to a string
 370 */
 371 void luaO_tostring (lua_State *L, StkId obj) {
 372   char buff[MAXNUMBER2STR];
 373   size_t len;
 374   lua_assert(ttisnumber(obj));
 375   if (ttisinteger(obj))
 376     len = lua_integer2str(buff, sizeof(buff), ivalue(obj));
 377   else {
 378     len = lua_number2str(buff, sizeof(buff), fltvalue(obj));
 379 #if !defined(LUA_COMPAT_FLOATSTRING)
 380     if (buff[strspn(buff, "-0123456789")] == '\0') {  /* looks like an int? */
 381       buff[len++] = lua_getlocaledecpoint();
 382       buff[len++] = '0';  /* adds '.0' to result */
 383     }
 384 #endif
 385   }
 386   setsvalue2s(L, obj, luaS_newlstr(L, buff, len));
 387 }
 388
 389
 390 static void pushstr (lua_State *L, const char *str, size_t l) {
 391   setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
 392   luaD_inctop(L);
 393 }
 394
 395
 396 /*
 397 ** this function handles only '%d', '%c', '%f', '%p', and '%s'
 398    conventional formats, plus Lua-specific '%I' and '%U'
 399 */
 400 const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
 401   int n = 0;
 402   for (;;) {
 403     const char *e = strchr(fmt, '%');
 404     if (e == NULL) break;
 405     pushstr(L, fmt, e - fmt);
 406     switch (*(e+1)) {
 407       case 's': {  /* zero-terminated string */
 408         const char *s = va_arg(argp, char *);
 409         if (s == NULL) s = "(null)";
 410         pushstr(L, s, strlen(s));
 411         break;
 412       }
 413       case 'c': {  /* an 'int' as a character */
 414         char buff = cast(char, va_arg(argp, int));
 415         if (lisprint(cast_uchar(buff)))
 416           pushstr(L, &buff, 1);
 417         else  /* non-printable character; print its code */
 418           luaO_pushfstring(L, "<\\%d>", cast_uchar(buff));
 419         break;
 420       }
 421       case 'd': {  /* an 'int' */
 422         setivalue(L->top, va_arg(argp, int));
 423         goto top2str;
 424       }
 425       case 'I': {  /* a 'lua_Integer' */
 426         setivalue(L->top, cast(lua_Integer, va_arg(argp, l_uacInt)));
 427         goto top2str;
 428       }
 429       case 'f': {  /* a 'lua_Number' */
 430         setfltvalue(L->top, cast_num(va_arg(argp, l_uacNumber)));
 431       top2str:  /* convert the top element to a string */
 432         luaD_inctop(L);
 433         luaO_tostring(L, L->top - 1);
 434         break;
 435       }
 436       case 'p': {  /* a pointer */
 437         char buff[4*sizeof(void *) + 8]; /* should be enough space for a '%p' */
 438         int l = l_sprintf(buff, sizeof(buff), "%p", va_arg(argp, void *));
 439         pushstr(L, buff, l);
 440         break;
 441       }
 442       case 'U': {  /* an 'int' as a UTF-8 sequence */
 443         char buff[UTF8BUFFSZ];
 444         int l = luaO_utf8esc(buff, cast(long, va_arg(argp, long)));
 445         pushstr(L, buff + UTF8BUFFSZ - l, l);
 446         break;
 447       }
 448       case '%': {
 449         pushstr(L, "%", 1);
 450         break;
 451       }
 452       default: {
 453         luaG_runerror(L, "invalid option '%%%c' to 'lua_pushfstring'",
 454                          *(e + 1));
 455       }
 456     }
 457     n += 2;
 458     fmt = e+2;
 459   }
 460   luaD_checkstack(L, 1);
 461   pushstr(L, fmt, strlen(fmt));
 462   if (n > 0) luaV_concat(L, n + 1);
 463   return svalue(L->top - 1);
 464 }
 465
 466
 467 const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
 468   const char *msg;
 469   va_list argp;
 470   va_start(argp, fmt);
 471   msg = luaO_pushvfstring(L, fmt, argp);
 472   va_end(argp);
 473   return msg;
 474 }
 475
 476
 477 /* number of chars of a literal string without the ending \0 */
 478 #define LL(x)   (sizeof(x)/sizeof(char) - 1)
 479
 480 #define RETS    "..."
 481 #define PRE     "[string \""
 482 #define POS     "\"]"
 483
 484 #define addstr(a,b,l)   ( memcpy(a,b,(l) * sizeof(char)), a += (l) )
 485
 486 void luaO_chunkid (char *out, const char *source, size_t bufflen) {
 487   size_t l = strlen(source);
 488   if (*source == '=') {  /* 'literal' source */
 489     if (l <= bufflen)  /* small enough? */
 490       memcpy(out, source + 1, l * sizeof(char));
 491     else {  /* truncate it */
 492       addstr(out, source + 1, bufflen - 1);
 493       *out = '\0';
 494     }
 495   }
 496   else if (*source == '@') {  /* file name */
 497     if (l <= bufflen)  /* small enough? */
 498       memcpy(out, source + 1, l * sizeof(char));
 499     else {  /* add '...' before rest of name */
 500       addstr(out, RETS, LL(RETS));
 501       bufflen -= LL(RETS);
 502       memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char));
 503     }
 504   }
 505   else {  /* string; format as [string "source"] */
 506     const char *nl = strchr(source, '\n');  /* find first new line (if any) */
 507     addstr(out, PRE, LL(PRE));  /* add prefix */
 508     bufflen -= LL(PRE RETS POS) + 1;  /* save space for prefix+suffix+'\0' */
 509     if (l < bufflen && nl == NULL) {  /* small one-line source? */
 510       addstr(out, source, l);  /* keep it */
 511     }
 512     else {
 513       if (nl != NULL) l = nl - source;  /* stop at first newline */
 514       if (l > bufflen) l = bufflen;
 515       addstr(out, source, l);
 516       addstr(out, RETS, LL(RETS));
 517     }
 518     memcpy(out, POS, (LL(POS) + 1) * sizeof(char));
 519   }
 520 }
 521