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new function "luaO_str2d" to convert strings to numbers, because 

old "lex" algorithm had aproximation errors, but strtod (and atof
and scanf) are too slow.
v5-2
Roberto Ierusalimschy 26 years ago
parent
d2de2d5eda
commit
4c94d8cc2c
4 changed files with 108 additions and 76 deletions
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  1. 67
      llex.c
  2. 70
      lobject.c
  3. 4
      lobject.h
  4. 43
      lvm.c

67
llex.c
View File

@ -1,5 +1,5 @@
/*
** $Id: llex.c,v 1.24 1998/07/24 18:02:38 roberto Exp roberto $
** $Id: llex.c,v 1.25 1998/12/03 15:45:15 roberto Exp $
** Lexical Analizer
** See Copyright Notice in lua.h
*/
@ -46,7 +46,7 @@ void luaX_init (void)
void luaX_syntaxerror (LexState *ls, char *s, char *token) {
if (token[0] == 0)
if (token[0] == '\0')
token = "<eof>";
luaL_verror("%.100s;\n last token read: `%.50s' at line %d in chunk `%.50s'",
s, token, ls->linenumber, zname(ls->lex_z));
@ -54,7 +54,7 @@ void luaX_syntaxerror (LexState *ls, char *s, char *token) {
void luaX_error (LexState *ls, char *s) {
save(0);
save('\0');
luaX_syntaxerror(ls, s, luaL_buffer());
}
@ -62,7 +62,7 @@ void luaX_error (LexState *ls, char *s) {
void luaX_token2str (int token, char *s) {
if (token < 255) {
s[0] = token;
s[1] = 0;
s[1] = '\0';
}
else
strcpy(s, reserved[token-FIRST_RESERVED]);
@ -221,6 +221,7 @@ static void inclinenumber (LexState *LS)
}
/*
** =======================================================
** LEXICAL ANALIZER
@ -229,10 +230,7 @@ static void inclinenumber (LexState *LS)
static int read_long_string (LexState *LS)
{
static int read_long_string (LexState *LS) {
int cont = 0;
for (;;) {
switch (LS->current) {
@ -262,7 +260,7 @@ static int read_long_string (LexState *LS)
save_and_next(LS);
}
} endloop:
save_and_next(LS); /* pass the second ']' */
save_and_next(LS); /* skip the second ']' */
LS->seminfo.ts = luaS_newlstr(L->Mbuffbase+2,
L->Mbuffnext-(L->Mbuffbase-L->Mbuffer)-4);
return STRING;
@ -270,7 +268,6 @@ static int read_long_string (LexState *LS)
int luaX_lex (LexState *LS) {
double a;
luaL_resetbuffer();
for (;;) {
switch (LS->current) {
@ -347,7 +344,7 @@ int luaX_lex (LexState *LS) {
c = 10*c + (LS->current-'0');
next(LS);
} while (++i<3 && isdigit(LS->current));
if (c >= 256)
if (c > (unsigned char)c)
luaX_error(LS, "escape sequence too large");
save(c);
}
@ -382,15 +379,11 @@ int luaX_lex (LexState *LS) {
else return CONC; /* .. */
}
else if (!isdigit(LS->current)) return '.';
/* LS->current is a digit: goes through to number */
a=0.0;
goto fraction;
goto fraction; /* LS->current is a digit: goes through to number */
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
a=0.0;
do {
a = 10.0*a + (LS->current-'0');
save_and_next(LS);
} while (isdigit(LS->current));
if (LS->current == '.') {
@ -402,35 +395,19 @@ int luaX_lex (LexState *LS) {
}
}
fraction:
{ double da=0.1;
while (isdigit(LS->current))
{
a += (LS->current-'0')*da;
da /= 10.0;
save_and_next(LS);
}
if (toupper(LS->current) == 'E') {
int e = 0;
int neg;
double ea;
while (isdigit(LS->current))
save_and_next(LS);
if (toupper(LS->current) == 'E') {
save_and_next(LS); /* read 'E' */
save_and_next(LS); /* read '+', '-' or first digit */
while (isdigit(LS->current))
save_and_next(LS);
neg = (LS->current=='-');
if (LS->current == '+' || LS->current == '-') save_and_next(LS);
if (!isdigit(LS->current))
luaX_error(LS, "invalid numeral format");
do {
e = 10*e + (LS->current-'0');
save_and_next(LS);
} while (isdigit(LS->current));
for (ea=neg?0.1:10.0; e>0; e>>=1)
{
if (e & 1) a *= ea;
ea *= ea;
}
}
LS->seminfo.r = a;
return NUMBER;
}
save('\0');
LS->seminfo.r = luaO_str2d(L->Mbuffbase);
if (LS->seminfo.r < 0)
luaX_error(LS, "invalid numeric format");
return NUMBER;
case EOZ:
if (LS->iflevel > 0)
@ -450,9 +427,9 @@ int luaX_lex (LexState *LS) {
do {
save_and_next(LS);
} while (isalnum(LS->current) || LS->current == '_');
save(0);
save('\0');
ts = luaS_new(L->Mbuffbase);
if (ts->head.marked >= 'A')
if (ts->head.marked >= FIRST_RESERVED)
return ts->head.marked; /* reserved word */
LS->seminfo.ts = ts;
return NAME;

70
lobject.c
View File

@ -1,9 +1,10 @@
/*
** $Id: lobject.c,v 1.12 1998/06/18 16:57:03 roberto Exp roberto $
** $Id: lobject.c,v 1.13 1998/06/19 16:14:09 roberto Exp $
** Some generic functions over Lua objects
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <stdlib.h>
#include "lobject.h"
@ -64,20 +65,67 @@ void luaO_insertlist (GCnode *root, GCnode *node)
node->marked = 0;
}
#ifdef OLD_ANSI
void luaO_memup (void *dest, void *src, int size)
{
char *d = dest;
char *s = src;
while (size--) d[size]=s[size];
void luaO_memup (void *dest, void *src, int size) {
while (size--)
((char *)dest)[size]=((char *)src)[size];
}
void luaO_memdown (void *dest, void *src, int size)
{
char *d = dest;
char *s = src;
void luaO_memdown (void *dest, void *src, int size) {
int i;
for (i=0; i<size; i++) d[i]=s[i];
for (i=0; i<size; i++)
((char *)dest)[i]=((char *)src)[i];
}
#endif
static double expten (unsigned int e) {
double exp = 10.0;
double res = 1.0;
for (; e; e>>=1) {
if (e & 1) res *= exp;
exp *= exp;
}
return res;
}
double luaO_str2d (char *s) {
double a = 0.0;
int point = 0;
if (!isdigit((unsigned char)*s) && !isdigit((unsigned char)*(s+1)))
return -1; /* no digit before or after decimal point */
while (isdigit((unsigned char)*s)) {
a = 10.0*a + (*(s++)-'0');
}
if (*s == '.') s++;
while (isdigit((unsigned char)*s)) {
a = 10.0*a + (*(s++)-'0');
point++;
}
if (toupper((unsigned char)*s) == 'E') {
int e = 0;
int sig = 1;
s++;
if (*s == '+') s++;
else if (*s == '-') {
s++;
sig = -1;
}
if (!isdigit((unsigned char)*s)) return -1; /* no digit in expoent part? */
do {
e = 10*e + (*(s++)-'0');
} while (isdigit((unsigned char)*s));
point -= sig*e;
}
while (isspace((unsigned char)*s)) s++;
if (*s != '\0') return -1; /* invalid trailing characters? */
if (point > 0)
a /= expten(point);
else if (point < 0)
a *= expten(-point);
return a;
}

4
lobject.h
View File

@ -1,5 +1,5 @@
/*
** $Id: lobject.h,v 1.22 1998/07/12 16:11:55 roberto Exp roberto $
** $Id: lobject.h,v 1.23 1998/12/01 19:09:47 roberto Exp $
** Type definitions for Lua objects
** See Copyright Notice in lua.h
*/
@ -30,7 +30,6 @@
*/
#ifndef LUA_NUM_TYPE
#define LUA_NUM_TYPE double
#define NUMBER_FMT "%g"
#endif
@ -197,6 +196,7 @@ extern TObject luaO_nilobject;
int luaO_equalObj (TObject *t1, TObject *t2);
int luaO_redimension (int oldsize);
void luaO_insertlist (GCnode *root, GCnode *node);
double luaO_str2d (char *s);
#ifdef OLD_ANSI
void luaO_memup (void *dest, void *src, int size);

43
lvm.c
View File

@ -1,11 +1,12 @@
/*
** $Id: lvm.c,v 1.32 1998/12/03 15:45:15 roberto Exp roberto $
** $Id: lvm.c,v 1.33 1998/12/24 14:57:23 roberto Exp $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@ -15,6 +16,7 @@
#include "lfunc.h"
#include "lgc.h"
#include "lmem.h"
#include "lobject.h"
#include "lopcodes.h"
#include "lstate.h"
#include "lstring.h"
@ -26,7 +28,6 @@
#ifdef OLD_ANSI
#define strcoll(a,b) strcmp(a,b)
double strtod();
#endif
@ -40,11 +41,10 @@ double strtod();
static TaggedString *strconc (TaggedString *l, TaggedString *r)
{
size_t nl = l->u.s.len;
size_t nr = r->u.s.len;
char *buffer = luaL_openspace(nl+nr+1);
static TaggedString *strconc (TaggedString *l, TaggedString *r) {
long nl = l->u.s.len;
long nr = r->u.s.len;
char *buffer = luaL_openspace(nl+nr);
memcpy(buffer, l->str, nl);
memcpy(buffer+nl, r->str, nr);
return luaS_newlstr(buffer, nl+nr);
@ -56,29 +56,36 @@ int luaV_tonumber (TObject *obj) {
if (ttype(obj) != LUA_T_STRING)
return 1;
else {
char *e;
double t = strtod(svalue(obj), &e);
while (isspace(*e)) e++;
if (*e != '\0') return 2;
nvalue(obj) = (real)t;
double t;
char *e = svalue(obj);
int sig = 1;
while (isspace((unsigned char)*e)) e++;
if (*e == '+') e++;
else if (*e == '-') {
e++;
sig = -1;
}
t = luaO_str2d(e);
if (t<0) return 2;
nvalue(obj) = (real)t*sig;
ttype(obj) = LUA_T_NUMBER;
return 0;
}
}
int luaV_tostring (TObject *obj)
{ /* LUA_NUMBER */
int luaV_tostring (TObject *obj) {
/* LUA_NUMBER */
if (ttype(obj) != LUA_T_NUMBER)
return 1;
else {
char s[60];
real f = nvalue(obj);
int i;
if ((real)(-MAX_INT) <= f && f <= (real)MAX_INT && (real)(i=(int)f) == f)
sprintf (s, "%d", i);
long i;
if ((real)LONG_MIN <= f && f <= (real)LONG_MAX && (real)(i=(long)f) == f)
sprintf(s, "%ld", i);
else
sprintf (s, NUMBER_FMT, nvalue(obj));
sprintf(s, "%g", (double)nvalue(obj));
tsvalue(obj) = luaS_new(s);
ttype(obj) = LUA_T_STRING;
return 0;

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