gecko-dev/ef/Tools/Burg/lex.c

262 строки
4.2 KiB
C

char rcsid_lex[] = "$Id: lex.c,v 1.1 1998/12/17 06:36:47 fur%netscape.com Exp $";
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include "b.h"
#include "fe.h"
#include "y.tab.h"
static char buf[BUFSIZ];
static int yyline = 1;
typedef int (*ReadFn) ARGS((void));
static char *StrCopy ARGS((char *));
static int code_get ARGS((void));
static int simple_get ARGS((void));
static void ReadCharString ARGS((ReadFn, int));
static void ReadCodeBlock ARGS((void));
static void ReadOldComment ARGS((ReadFn));
static char *
StrCopy(s) char *s;
{
char *t = (char *)zalloc(strlen(s) + 1);
strcpy(t,s);
return t;
}
static int
simple_get()
{
int ch;
if ((ch = getchar()) == '\n') {
yyline++;
}
return ch;
}
static int
code_get()
{
int ch;
if ((ch = getchar()) == '\n') {
yyline++;
}
if (ch != EOF) {
fputc(ch, outfile);
}
return ch;
}
void
yypurge()
{
while (code_get() != EOF) ;
}
static void
ReadCharString(rdfn, which) ReadFn rdfn; int which;
{
int ch;
int backslash = 0;
int firstline = yyline;
while ((ch = rdfn()) != EOF) {
if (ch == which && !backslash) {
return;
}
if (ch == '\\' && !backslash) {
backslash = 1;
} else {
backslash = 0;
}
}
yyerror1("Unexpected EOF in string on line ");
fprintf(stderr, "%d\n", firstline);
exit(1);
}
static void
ReadOldComment(rdfn) ReadFn rdfn;
{
/* will not work for comments delimiter in string */
int ch;
int starred = 0;
int firstline = yyline;
while ((ch = rdfn()) != EOF) {
if (ch == '*') {
starred = 1;
} else if (ch == '/' && starred) {
return;
} else {
starred = 0;
}
}
yyerror1("Unexpected EOF in comment on line ");
fprintf(stderr, "%d\n", firstline);
exit(1);
}
static void
ReadCodeBlock()
{
int ch;
int firstline = yyline;
while ((ch = getchar()) != EOF) {
if (ch == '%') {
ch = getchar();
if (ch != '}') {
yyerror("bad %%");
}
return;
}
fputc(ch, outfile);
if (ch == '\n') {
yyline++;
}
if (ch == '"' || ch == '\'') {
ReadCharString(code_get, ch);
} else if (ch == '/') {
ch = getchar();
if (ch == '*') {
fputc(ch, outfile);
ReadOldComment(code_get);
continue;
} else {
ungetc(ch, stdin);
}
}
}
yyerror1("Unclosed block of C code started on line ");
fprintf(stderr, "%d\n", firstline);
exit(1);
}
static int done;
void
yyfinished()
{
done = 1;
}
int
yylex()
{
int ch;
char *ptr = buf;
if (done) return 0;
while ((ch = getchar()) != EOF) {
switch (ch) {
case ' ':
case '\f':
case '\t':
continue;
case '\n':
yyline++;
continue;
case '(':
case ')':
case ',':
case ':':
case ';':
case '=':
return(ch);
case '/':
ch = getchar();
if (ch == '*') {
ReadOldComment(simple_get);
continue;
} else {
ungetc(ch, stdin);
yyerror("illegal char /");
continue;
}
case '%':
ch = getchar();
switch (ch) {
case '%':
return (K_PPERCENT);
case '{':
ReadCodeBlock();
continue;
case 'l':
case 'u':
case 'b':
case 's':
case 't':
do {
if (ptr >= &buf[BUFSIZ]) {
yyerror("ID too long");
return(ERROR);
} else {
*ptr++ = ch;
}
ch = getchar();
} while (isalpha(ch) || isdigit(ch) || ch == '_');
ungetc(ch, stdin);
*ptr = '\0';
if (!strcmp(buf, "term")) return K_TERM;
if (!strcmp(buf, "start")) return K_START;
yyerror("illegal character after %%");
continue;
default:
yyerror("illegal character after %%");
continue;
}
default:
if (isalpha(ch) ) {
do {
if (ptr >= &buf[BUFSIZ]) {
yyerror("ID too long");
return(ERROR);
} else {
*ptr++ = ch;
}
ch = getchar();
} while (isalpha(ch) || isdigit(ch) || ch == '_');
ungetc(ch, stdin);
*ptr = '\0';
yylval.y_string = StrCopy(buf);
return(ID);
}
if (isdigit(ch)) {
int val=0;
do {
val *= 10;
val += (ch - '0');
ch = getchar();
} while (isdigit(ch));
ungetc(ch, stdin);
yylval.y_int = val;
return(INT);
}
yyerror1("illegal char ");
fprintf(stderr, "(\\%03o)\n", ch);
exit(1);
}
}
return(0);
}
void
yyerror1(str) char *str;
{
fprintf(stderr, "line %d: %s", yyline, str);
}
void
yyerror(str) char *str;
{
yyerror1(str);
fprintf(stderr, "\n");
exit(1);
}