lua/lobject.c
2010-04-18 10:22:48 -03:00

237 lines
6.3 KiB
C

/*
** $Id: lobject.c,v 2.39 2010/04/15 19:44:43 roberto Exp roberto $
** Some generic functions over Lua objects
** See Copyright Notice in lua.h
*/
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define lobject_c
#define LUA_CORE
#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 (lu_int32 x) {
int e = 0; /* exponent */
if (x < 8) return x;
while (x >= 0x10) {
x = (x+1) >> 1;
e++;
}
return ((e+1) << 3) | (cast_int(x) - 8);
}
/* converts back */
int luaO_fb2int (int x) {
int e = (x >> 3) & 0x1f;
if (e == 0) return x;
else return ((x & 7) + 8) << (e - 1);
}
int luaO_ceillog2 (unsigned int x) {
static const lu_byte log_2[256] = {
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];
}
int luaO_rawequalObj (const TValue *t1, const TValue *t2) {
if (ttype(t1) != ttype(t2)) return 0;
else switch (ttype(t1)) {
case LUA_TNIL:
return 1;
case LUA_TNUMBER:
return luai_numeq(nvalue(t1), nvalue(t2));
case LUA_TBOOLEAN:
return bvalue(t1) == bvalue(t2); /* boolean true must be 1 !! */
case LUA_TLIGHTUSERDATA:
return pvalue(t1) == pvalue(t2);
case LUA_TSTRING:
return rawtsvalue(t1) == rawtsvalue(t2);
case LUA_TLCF:
return fvalue(t1) == fvalue(t2);
default:
lua_assert(iscollectable(t1));
return gcvalue(t1) == gcvalue(t2);
}
}
lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {
switch (op) {
case LUA_OPADD: return luai_numadd(NULL, v1, v2);
case LUA_OPSUB: return luai_numsub(NULL, v1, v2);
case LUA_OPMUL: return luai_nummul(NULL, v1, v2);
case LUA_OPDIV: return luai_numdiv(NULL, v1, v2);
case LUA_OPMOD: return luai_nummod(NULL, v1, v2);
case LUA_OPPOW: return luai_numpow(NULL, v1, v2);
case LUA_OPUNM: return luai_numunm(NULL, v1);
default: lua_assert(0); return 0;
}
}
int luaO_str2d (const char *s, lua_Number *result) {
char *endptr;
*result = lua_str2number(s, &endptr);
if (endptr == s) return 0; /* conversion failed */
if (*endptr == 'x' || *endptr == 'X') /* maybe an hexadecimal constant? */
*result = cast_num(strtoul(s, &endptr, 16));
while (lisspace(cast(unsigned char, *endptr))) endptr++;
return (*endptr == '\0'); /* OK if no trailing characters */
}
static void pushstr (lua_State *L, const char *str, size_t l) {
setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
incr_top(L);
}
/* this function handles only `%d', `%c', %f, %p, and `%s' formats */
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;
setsvalue2s(L, L->top, luaS_newlstr(L, fmt, e-fmt));
incr_top(L);
switch (*(e+1)) {
case 's': {
const char *s = va_arg(argp, char *);
if (s == NULL) s = "(null)";
pushstr(L, s, strlen(s));
break;
}
case 'c': {
char buff;
buff = cast(char, va_arg(argp, int));
pushstr(L, &buff, 1);
break;
}
case 'd': {
setnvalue(L->top, cast_num(va_arg(argp, int)));
incr_top(L);
break;
}
case 'f': {
setnvalue(L->top, cast_num(va_arg(argp, l_uacNumber)));
incr_top(L);
break;
}
case 'p': {
char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */
int l = sprintf(buff, "%p", va_arg(argp, void *));
pushstr(L, buff, l);
break;
}
case '%': {
pushstr(L, "%", 1);
break;
}
default: {
luaG_runerror(L,
"invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"),
*(e + 1));
break;
}
}
n += 2;
fmt = e+2;
}
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;
}
#define LL(x) (sizeof(x) - 1)
#define RETS "..."
#define PRE "[string \""
#define POS "\"]"
#define addstr(a,b,l) ( memcpy(a,b,l), 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);
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);
else { /* add '...' before rest of name */
addstr(out, RETS, LL(RETS));
bufflen -= LL(RETS);
memcpy(out, source + 1 + l - bufflen, bufflen);
}
}
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); /* save space for prefix+suffix */
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);
}
}