`scan_hex` may be used to parse both unicode and hex escape.
The error checks for both usage should be separated; ref
MODIFY
mrbgems/mruby-compiler/core/parse.y
mrbgems/mruby-compiler/core/parse.y
@@ -3783,10 +3783,6 @@ scan_hex(parser_state *p, const int *start, int len, int *retlen)
}
*retlen = s - start;
- if (*retlen == 0 || retval > 0x10FFFF || (retval & 0xFFFFF800) == 0xD800) {
- yyerror(p, "Invalid Unicode code point");
- return -1;
- }
return (int32_t)retval;
}
@@ -3795,13 +3791,14 @@ read_escape_unicode(parser_state *p, int limit)
{
int buf[9];
int i;
+ int32_t hex;
/* Look for opening brace */
i = 0;
buf[0] = nextc(p);
if (buf[0] < 0) {
eof:
- yyerror(p, "Invalid escape character syntax");
+ yyerror(p, "invalid escape character syntax");
return -1;
}
if (ISXDIGIT(buf[0])) {
@@ -3818,7 +3815,12 @@ read_escape_unicode(parser_state *p, int limit)
else {
pushback(p, buf[0]);
}
- return scan_hex(p, buf, i, &i);
+ hex = scan_hex(p, buf, i, &i);
+ if (i == 0 || hex > 0x10FFFF || (hex & 0xFFFFF800) == 0xD800) {
+ yyerror(p, "invalid Unicode code point");
+ return -1;
+ }
+ return hex;
}
/* Return negative to indicate Unicode code point */
@@ -3884,6 +3886,10 @@ read_escape(parser_state *p)
break;
}
}
+ if (i == 0) {
+ yyerror(p, "invalid hex escape");
+ return -1;
+ }
return scan_hex(p, buf, i, &i);
}

`scan_hex` may be used to parse both unicode and hex escape.

The error checks for both usage should be separated; ref #3774