char *rcs_lex = "$Id: lex.c,v 2.4 1994/09/05 19:14:40 celes Exp lhf $";
/*$Log: lex.c,v $
* Revision 2.4 1994/09/05 19:14:40 celes
* escapes \' e \" em strings; correcao do escape \\
*
* Revision 2.3 1994/08/17 17:41:50 celes
* Implementacao da macro 'lua_strcmp'
*
* Revision 2.2 1994/08/05 19:27:41 celes
* implementacao de dois buffer de 'yytext' para evitar bug
* no look ahead do yacc
*
* Revision 2.1 1994/04/15 19:00:28 celes
* Retirar chamada da funcao lua_findsymbol associada a cada
* token NAME. A decisao de chamar lua_findsymbol ou lua_findconstant
* fica a cargo do modulo "lua.stx".
*
* Revision 1.3 1993/12/28 16:42:29 roberto
* "include"s de string.h e stdlib.h para evitar warnings
*
* Revision 1.2 1993/12/22 21:39:15 celes
* Tratamento do token $debug e $nodebug
*
* Revision 1.1 1993/12/22 21:15:16 roberto
* Initial revision
**/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include "opcode.h"
#include "hash.h"
#include "inout.h"
#include "table.h"
#include "y.tab.h"
#define lua_strcmp(a,b) (a[0]<b[0]?(-1):(a[0]>b[0]?(1):strcmp(a,b)))
#define next() { current = input(); }
#define save(x) { *yytextLast++ = (x); }
#define save_and_next() { save(current); next(); }
static int current;
static char yytext[2][256];
static char *yytextLast;
static int currentText = 0;
static Input input;
void lua_setinput (Input fn)
{
current = ' ';
input = fn;
}
char *lua_lasttext (void)
{
*yytextLast = 0;
return yytext[currentText];
}
/* The reserved words must be listed in lexicographic order */
static struct
{
char *name;
int token;
} reserved [] = {
{"and", AND},
{"do", DO},
{"else", ELSE},
{"elseif", ELSEIF},
{"end", END},
{"function", FUNCTION},
{"if", IF},
{"local", LOCAL},
{"nil", NIL},
{"not", NOT},
{"or", OR},
{"repeat", REPEAT},
{"return", RETURN},
{"then", THEN},
{"until", UNTIL},
{"while", WHILE} };
enum
{
U_and=128,
U_do,
U_else,
U_elseif,
U_end,
U_function,
U_if,
U_local,
U_nil,
U_not,
U_or,
U_repeat,
U_return,
U_then,
U_until,
U_while,
U_le = '<'+128,
U_ge = '>'+128,
U_ne = '~'+128,
U_sc = '.'+128
};
#define RESERVEDSIZE (sizeof(reserved)/sizeof(reserved[0]))
static int findReserved (char *name)
{
int l = 0;
int h = RESERVEDSIZE - 1;
while (l <= h)
{
int m = (l+h)/2;
int comp = lua_strcmp(name, reserved[m].name);
if (comp < 0)
h = m-1;
else if (comp == 0)
return reserved[m].token;
else
l = m+1;
}
return 0;
}
int yylex ()
{
currentText = !currentText;
while (1)
{
yytextLast = yytext[currentText];
switch (current)
{
case '\n': lua_linenumber++;
case ' ':
case '\t':
next();
continue;
case '$':
next();
while (isalnum(current) || current == '_')
save_and_next();
*yytextLast = 0;
if (lua_strcmp(yytext[currentText], "debug") == 0)
{
yylval.vInt = 1;
return DEBUG;
}
else if (lua_strcmp(yytext[currentText], "nodebug") == 0)
{
yylval.vInt = 0;
return DEBUG;
}
return WRONGTOKEN;
case '-':
save_and_next();
if (current != '-') return '-';
do { next(); } while (current != '\n' && current != 0);
continue;
case '<':
save_and_next();
if (current != '=') return '<';
else { save_and_next(); return LE; }
case '>':
save_and_next();
if (current != '=') return '>';
else { save_and_next(); return GE; }
case '~':
save_and_next();
if (current != '=') return '~';
else { save_and_next(); return NE; }
case '"':
case '\'':
{
int del = current;
next(); /* skip the delimiter */
while (current != del)
{
switch (current)
{
case 0:
case '\n':
return WRONGTOKEN;
case '\\':
next(); /* do not save the '\' */
switch (current)
{
case 'n': save('\n'); next(); break;
case 't': save('\t'); next(); break;
case 'r': save('\r'); next(); break;
case '\'': save('\''); next(); break;
case '"': save('"'); next(); break;
default : save(current); next(); break;
}
break;
default:
save_and_next();
}
}
next(); /* skip the delimiter */
*yytextLast = 0;
yylval.vWord = lua_findconstant (yytext[currentText]);
return STRING;
}
case 'a': case 'b': case 'c': case 'd': case 'e':
case 'f': case 'g': case 'h': case 'i': case 'j':
case 'k': case 'l': case 'm': case 'n': case 'o':
case 'p': case 'q': case 'r': case 's': case 't':
case 'u': case 'v': case 'w': case 'x': case 'y':
case 'z':
case 'A': case 'B': case 'C': case 'D': case 'E':
case 'F': case 'G': case 'H': case 'I': case 'J':
case 'K': case 'L': case 'M': case 'N': case 'O':
case 'P': case 'Q': case 'R': case 'S': case 'T':
case 'U': case 'V': case 'W': case 'X': case 'Y':
case 'Z':
case '_':
{
int res;
do { save_and_next(); } while (isalnum(current) || current == '_');
*yytextLast = 0;
res = findReserved(yytext[currentText]);
if (res) return res;
yylval.pChar = yytext[currentText];
return NAME;
}
case '.':
save_and_next();
if (current == '.')
{
save_and_next();
return CONC;
}
else if (!isdigit(current)) return '.';
/* current is a digit: goes through to number */
goto fraction;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
do { save_and_next(); } while (isdigit(current));
if (current == '.') save_and_next();
fraction: while (isdigit(current)) save_and_next();
if (current == 'e' || current == 'E')
{
save_and_next();
if (current == '+' || current == '-') save_and_next();
if (!isdigit(current)) return WRONGTOKEN;
do { save_and_next(); } while (isdigit(current));
}
*yytextLast = 0;
yylval.vFloat = atof(yytext[currentText]);
return NUMBER;
case U_and: return AND;
case U_do: return DO;
case U_else: return ELSE;
case U_elseif: return ELSEIF;
case U_end: return END;
case U_function: return FUNCTION;
case U_if: return IF;
case U_local: return LOCAL;
case U_nil: return NIL;
case U_not: return NOT;
case U_or: return OR;
case U_repeat: return REPEAT;
case U_return: return RETURN;
case U_then: return THEN;
case U_until: return UNTIL;
case U_while: return WHILE;
case U_le: return LE;
case U_ge: return GE;
case U_ne: return NE;
case U_sc: return CONC;
default: /* also end of file */
{
save_and_next();
return yytext[currentText][0];
}
}
}
}