diff options
author | kyren <kerriganw@gmail.com> | 2017-05-21 19:50:59 -0400 |
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committer | kyren <kerriganw@gmail.com> | 2017-05-21 19:50:59 -0400 |
commit | 065c69894a08dc52e7a1baba9154681d6c0fa834 (patch) | |
tree | 76bcf03a8aa291f465dfb5f216389a21baaa5d1a /lua/lobject.c | |
download | mlua-065c69894a08dc52e7a1baba9154681d6c0fa834.zip |
Initial import
Diffstat (limited to 'lua/lobject.c')
-rw-r--r-- | lua/lobject.c | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/lua/lobject.c b/lua/lobject.c new file mode 100644 index 0000000..2da7689 --- /dev/null +++ b/lua/lobject.c @@ -0,0 +1,521 @@ +/* +** $Id: lobject.c,v 2.113 2016/12/22 13:08:50 roberto Exp $ +** Some generic functions over Lua objects +** See Copyright Notice in lua.h +*/ + +#define lobject_c +#define LUA_CORE + +#include "lprefix.h" + + +#include <locale.h> +#include <math.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "lua.h" + +#include "lctype.h" +#include "ldebug.h" +#include "ldo.h" +#include "lmem.h" +#include "lobject.h" +#include "lstate.h" +#include "lstring.h" +#include "lvm.h" + + + +LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT}; + + +/* +** converts an integer to a "floating point byte", represented as +** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if +** eeeee != 0 and (xxx) otherwise. +*/ +int luaO_int2fb (unsigned int x) { + int e = 0; /* exponent */ + if (x < 8) return x; + while (x >= (8 << 4)) { /* coarse steps */ + x = (x + 0xf) >> 4; /* x = ceil(x / 16) */ + e += 4; + } + while (x >= (8 << 1)) { /* fine steps */ + x = (x + 1) >> 1; /* x = ceil(x / 2) */ + e++; + } + return ((e+1) << 3) | (cast_int(x) - 8); +} + + +/* converts back */ +int luaO_fb2int (int x) { + return (x < 8) ? x : ((x & 7) + 8) << ((x >> 3) - 1); +} + + +/* +** Computes ceil(log2(x)) +*/ +int luaO_ceillog2 (unsigned int x) { + static const lu_byte log_2[256] = { /* log_2[i] = ceil(log2(i - 1)) */ + 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, + 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, + 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, + 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, + 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, + 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, + 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, + 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 + }; + int l = 0; + x--; + while (x >= 256) { l += 8; x >>= 8; } + return l + log_2[x]; +} + + +static lua_Integer intarith (lua_State *L, int op, lua_Integer v1, + lua_Integer v2) { + switch (op) { + case LUA_OPADD: return intop(+, v1, v2); + case LUA_OPSUB:return intop(-, v1, v2); + case LUA_OPMUL:return intop(*, v1, v2); + case LUA_OPMOD: return luaV_mod(L, v1, v2); + case LUA_OPIDIV: return luaV_div(L, v1, v2); + case LUA_OPBAND: return intop(&, v1, v2); + case LUA_OPBOR: return intop(|, v1, v2); + case LUA_OPBXOR: return intop(^, v1, v2); + case LUA_OPSHL: return luaV_shiftl(v1, v2); + case LUA_OPSHR: return luaV_shiftl(v1, -v2); + case LUA_OPUNM: return intop(-, 0, v1); + case LUA_OPBNOT: return intop(^, ~l_castS2U(0), v1); + default: lua_assert(0); return 0; + } +} + + +static lua_Number numarith (lua_State *L, int op, lua_Number v1, + lua_Number v2) { + switch (op) { + case LUA_OPADD: return luai_numadd(L, v1, v2); + case LUA_OPSUB: return luai_numsub(L, v1, v2); + case LUA_OPMUL: return luai_nummul(L, v1, v2); + case LUA_OPDIV: return luai_numdiv(L, v1, v2); + case LUA_OPPOW: return luai_numpow(L, v1, v2); + case LUA_OPIDIV: return luai_numidiv(L, v1, v2); + case LUA_OPUNM: return luai_numunm(L, v1); + case LUA_OPMOD: { + lua_Number m; + luai_nummod(L, v1, v2, m); + return m; + } + default: lua_assert(0); return 0; + } +} + + +void luaO_arith (lua_State *L, int op, const TValue *p1, const TValue *p2, + TValue *res) { + switch (op) { + case LUA_OPBAND: case LUA_OPBOR: case LUA_OPBXOR: + case LUA_OPSHL: case LUA_OPSHR: + case LUA_OPBNOT: { /* operate only on integers */ + lua_Integer i1; lua_Integer i2; + if (tointeger(p1, &i1) && tointeger(p2, &i2)) { + setivalue(res, intarith(L, op, i1, i2)); + return; + } + else break; /* go to the end */ + } + case LUA_OPDIV: case LUA_OPPOW: { /* operate only on floats */ + lua_Number n1; lua_Number n2; + if (tonumber(p1, &n1) && tonumber(p2, &n2)) { + setfltvalue(res, numarith(L, op, n1, n2)); + return; + } + else break; /* go to the end */ + } + default: { /* other operations */ + lua_Number n1; lua_Number n2; + if (ttisinteger(p1) && ttisinteger(p2)) { + setivalue(res, intarith(L, op, ivalue(p1), ivalue(p2))); + return; + } + else if (tonumber(p1, &n1) && tonumber(p2, &n2)) { + setfltvalue(res, numarith(L, op, n1, n2)); + return; + } + else break; /* go to the end */ + } + } + /* could not perform raw operation; try metamethod */ + lua_assert(L != NULL); /* should not fail when folding (compile time) */ + luaT_trybinTM(L, p1, p2, res, cast(TMS, (op - LUA_OPADD) + TM_ADD)); +} + + +int luaO_hexavalue (int c) { + if (lisdigit(c)) return c - '0'; + else return (ltolower(c) - 'a') + 10; +} + + +static int isneg (const char **s) { + if (**s == '-') { (*s)++; return 1; } + else if (**s == '+') (*s)++; + return 0; +} + + + +/* +** {================================================================== +** Lua's implementation for 'lua_strx2number' +** =================================================================== +*/ + +#if !defined(lua_strx2number) + +/* maximum number of significant digits to read (to avoid overflows + even with single floats) */ +#define MAXSIGDIG 30 + +/* +** convert an hexadecimal numeric string to a number, following +** C99 specification for 'strtod' +*/ +static lua_Number lua_strx2number (const char *s, char **endptr) { + int dot = lua_getlocaledecpoint(); + lua_Number r = 0.0; /* result (accumulator) */ + int sigdig = 0; /* number of significant digits */ + int nosigdig = 0; /* number of non-significant digits */ + int e = 0; /* exponent correction */ + int neg; /* 1 if number is negative */ + int hasdot = 0; /* true after seen a dot */ + *endptr = cast(char *, s); /* nothing is valid yet */ + while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */ + neg = isneg(&s); /* check signal */ + if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X'))) /* check '0x' */ + return 0.0; /* invalid format (no '0x') */ + for (s += 2; ; s++) { /* skip '0x' and read numeral */ + if (*s == dot) { + if (hasdot) break; /* second dot? stop loop */ + else hasdot = 1; + } + else if (lisxdigit(cast_uchar(*s))) { + if (sigdig == 0 && *s == '0') /* non-significant digit (zero)? */ + nosigdig++; + else if (++sigdig <= MAXSIGDIG) /* can read it without overflow? */ + r = (r * cast_num(16.0)) + luaO_hexavalue(*s); + else e++; /* too many digits; ignore, but still count for exponent */ + if (hasdot) e--; /* decimal digit? correct exponent */ + } + else break; /* neither a dot nor a digit */ + } + if (nosigdig + sigdig == 0) /* no digits? */ + return 0.0; /* invalid format */ + *endptr = cast(char *, s); /* valid up to here */ + e *= 4; /* each digit multiplies/divides value by 2^4 */ + if (*s == 'p' || *s == 'P') { /* exponent part? */ + int exp1 = 0; /* exponent value */ + int neg1; /* exponent signal */ + s++; /* skip 'p' */ + neg1 = isneg(&s); /* signal */ + if (!lisdigit(cast_uchar(*s))) + return 0.0; /* invalid; must have at least one digit */ + while (lisdigit(cast_uchar(*s))) /* read exponent */ + exp1 = exp1 * 10 + *(s++) - '0'; + if (neg1) exp1 = -exp1; + e += exp1; + *endptr = cast(char *, s); /* valid up to here */ + } + if (neg) r = -r; + return l_mathop(ldexp)(r, e); +} + +#endif +/* }====================================================== */ + + +/* maximum length of a numeral */ +#if !defined (L_MAXLENNUM) +#define L_MAXLENNUM 200 +#endif + +static const char *l_str2dloc (const char *s, lua_Number *result, int mode) { + char *endptr; + *result = (mode == 'x') ? lua_strx2number(s, &endptr) /* try to convert */ + : lua_str2number(s, &endptr); + if (endptr == s) return NULL; /* nothing recognized? */ + while (lisspace(cast_uchar(*endptr))) endptr++; /* skip trailing spaces */ + return (*endptr == '\0') ? endptr : NULL; /* OK if no trailing characters */ +} + + +/* +** Convert string 's' to a Lua number (put in 'result'). Return NULL +** on fail or the address of the ending '\0' on success. +** 'pmode' points to (and 'mode' contains) special things in the string: +** - 'x'/'X' means an hexadecimal numeral +** - 'n'/'N' means 'inf' or 'nan' (which should be rejected) +** - '.' just optimizes the search for the common case (nothing special) +** This function accepts both the current locale or a dot as the radix +** mark. If the convertion fails, it may mean number has a dot but +** locale accepts something else. In that case, the code copies 's' +** to a buffer (because 's' is read-only), changes the dot to the +** current locale radix mark, and tries to convert again. +*/ +static const char *l_str2d (const char *s, lua_Number *result) { + const char *endptr; + const char *pmode = strpbrk(s, ".xXnN"); + int mode = pmode ? ltolower(cast_uchar(*pmode)) : 0; + if (mode == 'n') /* reject 'inf' and 'nan' */ + return NULL; + endptr = l_str2dloc(s, result, mode); /* try to convert */ + if (endptr == NULL) { /* failed? may be a different locale */ + char buff[L_MAXLENNUM + 1]; + const char *pdot = strchr(s, '.'); + if (strlen(s) > L_MAXLENNUM || pdot == NULL) + return NULL; /* string too long or no dot; fail */ + strcpy(buff, s); /* copy string to buffer */ + buff[pdot - s] = lua_getlocaledecpoint(); /* correct decimal point */ + endptr = l_str2dloc(buff, result, mode); /* try again */ + if (endptr != NULL) + endptr = s + (endptr - buff); /* make relative to 's' */ + } + return endptr; +} + + +#define MAXBY10 cast(lua_Unsigned, LUA_MAXINTEGER / 10) +#define MAXLASTD cast_int(LUA_MAXINTEGER % 10) + +static const char *l_str2int (const char *s, lua_Integer *result) { + lua_Unsigned a = 0; + int empty = 1; + int neg; + while (lisspace(cast_uchar(*s))) s++; /* skip initial spaces */ + neg = isneg(&s); + if (s[0] == '0' && + (s[1] == 'x' || s[1] == 'X')) { /* hex? */ + s += 2; /* skip '0x' */ + for (; lisxdigit(cast_uchar(*s)); s++) { + a = a * 16 + luaO_hexavalue(*s); + empty = 0; + } + } + else { /* decimal */ + for (; lisdigit(cast_uchar(*s)); s++) { + int d = *s - '0'; + if (a >= MAXBY10 && (a > MAXBY10 || d > MAXLASTD + neg)) /* overflow? */ + return NULL; /* do not accept it (as integer) */ + a = a * 10 + d; + empty = 0; + } + } + while (lisspace(cast_uchar(*s))) s++; /* skip trailing spaces */ + if (empty || *s != '\0') return NULL; /* something wrong in the numeral */ + else { + *result = l_castU2S((neg) ? 0u - a : a); + return s; + } +} + + +size_t luaO_str2num (const char *s, TValue *o) { + lua_Integer i; lua_Number n; + const char *e; + if ((e = l_str2int(s, &i)) != NULL) { /* try as an integer */ + setivalue(o, i); + } + else if ((e = l_str2d(s, &n)) != NULL) { /* else try as a float */ + setfltvalue(o, n); + } + else + return 0; /* conversion failed */ + return (e - s) + 1; /* success; return string size */ +} + + +int luaO_utf8esc (char *buff, unsigned long x) { + int n = 1; /* number of bytes put in buffer (backwards) */ + lua_assert(x <= 0x10FFFF); + if (x < 0x80) /* ascii? */ + buff[UTF8BUFFSZ - 1] = cast(char, x); + else { /* need continuation bytes */ + unsigned int mfb = 0x3f; /* maximum that fits in first byte */ + do { /* add continuation bytes */ + buff[UTF8BUFFSZ - (n++)] = cast(char, 0x80 | (x & 0x3f)); + x >>= 6; /* remove added bits */ + mfb >>= 1; /* now there is one less bit available in first byte */ + } while (x > mfb); /* still needs continuation byte? */ + buff[UTF8BUFFSZ - n] = cast(char, (~mfb << 1) | x); /* add first byte */ + } + return n; +} + + +/* maximum length of the conversion of a number to a string */ +#define MAXNUMBER2STR 50 + + +/* +** Convert a number object to a string +*/ +void luaO_tostring (lua_State *L, StkId obj) { + char buff[MAXNUMBER2STR]; + size_t len; + lua_assert(ttisnumber(obj)); + if (ttisinteger(obj)) + len = lua_integer2str(buff, sizeof(buff), ivalue(obj)); + else { + len = lua_number2str(buff, sizeof(buff), fltvalue(obj)); +#if !defined(LUA_COMPAT_FLOATSTRING) + if (buff[strspn(buff, "-0123456789")] == '\0') { /* looks like an int? */ + buff[len++] = lua_getlocaledecpoint(); + buff[len++] = '0'; /* adds '.0' to result */ + } +#endif + } + setsvalue2s(L, obj, luaS_newlstr(L, buff, len)); +} + + +static void pushstr (lua_State *L, const char *str, size_t l) { + setsvalue2s(L, L->top, luaS_newlstr(L, str, l)); + luaD_inctop(L); +} + + +/* +** this function handles only '%d', '%c', '%f', '%p', and '%s' + conventional formats, plus Lua-specific '%I' and '%U' +*/ +const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) { + int n = 0; + for (;;) { + const char *e = strchr(fmt, '%'); + if (e == NULL) break; + pushstr(L, fmt, e - fmt); + switch (*(e+1)) { + case 's': { /* zero-terminated string */ + const char *s = va_arg(argp, char *); + if (s == NULL) s = "(null)"; + pushstr(L, s, strlen(s)); + break; + } + case 'c': { /* an 'int' as a character */ + char buff = cast(char, va_arg(argp, int)); + if (lisprint(cast_uchar(buff))) + pushstr(L, &buff, 1); + else /* non-printable character; print its code */ + luaO_pushfstring(L, "<\\%d>", cast_uchar(buff)); + break; + } + case 'd': { /* an 'int' */ + setivalue(L->top, va_arg(argp, int)); + goto top2str; + } + case 'I': { /* a 'lua_Integer' */ + setivalue(L->top, cast(lua_Integer, va_arg(argp, l_uacInt))); + goto top2str; + } + case 'f': { /* a 'lua_Number' */ + setfltvalue(L->top, cast_num(va_arg(argp, l_uacNumber))); + top2str: /* convert the top element to a string */ + luaD_inctop(L); + luaO_tostring(L, L->top - 1); + break; + } + case 'p': { /* a pointer */ + char buff[4*sizeof(void *) + 8]; /* should be enough space for a '%p' */ + int l = l_sprintf(buff, sizeof(buff), "%p", va_arg(argp, void *)); + pushstr(L, buff, l); + break; + } + case 'U': { /* an 'int' as a UTF-8 sequence */ + char buff[UTF8BUFFSZ]; + int l = luaO_utf8esc(buff, cast(long, va_arg(argp, long))); + pushstr(L, buff + UTF8BUFFSZ - l, l); + break; + } + case '%': { + pushstr(L, "%", 1); + break; + } + default: { + luaG_runerror(L, "invalid option '%%%c' to 'lua_pushfstring'", + *(e + 1)); + } + } + n += 2; + fmt = e+2; + } + luaD_checkstack(L, 1); + pushstr(L, fmt, strlen(fmt)); + if (n > 0) luaV_concat(L, n + 1); + return svalue(L->top - 1); +} + + +const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) { + const char *msg; + va_list argp; + va_start(argp, fmt); + msg = luaO_pushvfstring(L, fmt, argp); + va_end(argp); + return msg; +} + + +/* number of chars of a literal string without the ending \0 */ +#define LL(x) (sizeof(x)/sizeof(char) - 1) + +#define RETS "..." +#define PRE "[string \"" +#define POS "\"]" + +#define addstr(a,b,l) ( memcpy(a,b,(l) * sizeof(char)), a += (l) ) + +void luaO_chunkid (char *out, const char *source, size_t bufflen) { + size_t l = strlen(source); + if (*source == '=') { /* 'literal' source */ + if (l <= bufflen) /* small enough? */ + memcpy(out, source + 1, l * sizeof(char)); + else { /* truncate it */ + addstr(out, source + 1, bufflen - 1); + *out = '\0'; + } + } + else if (*source == '@') { /* file name */ + if (l <= bufflen) /* small enough? */ + memcpy(out, source + 1, l * sizeof(char)); + else { /* add '...' before rest of name */ + addstr(out, RETS, LL(RETS)); + bufflen -= LL(RETS); + memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char)); + } + } + else { /* string; format as [string "source"] */ + const char *nl = strchr(source, '\n'); /* find first new line (if any) */ + addstr(out, PRE, LL(PRE)); /* add prefix */ + bufflen -= LL(PRE RETS POS) + 1; /* save space for prefix+suffix+'\0' */ + if (l < bufflen && nl == NULL) { /* small one-line source? */ + addstr(out, source, l); /* keep it */ + } + else { + if (nl != NULL) l = nl - source; /* stop at first newline */ + if (l > bufflen) l = bufflen; + addstr(out, source, l); + addstr(out, RETS, LL(RETS)); + } + memcpy(out, POS, (LL(POS) + 1) * sizeof(char)); + } +} + |