shithub: libmujs

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Optimize js_isarrayindex.

Avoid floating point number conversions.

--- a/jsrun.c

+++ b/jsrun.c

@@ -434,12 +434,20 @@

 /* Property access that takes care of attributes and getters/setters */

-int js_isarrayindex(js_State *J, const char *str, int *idx)

+int js_isarrayindex(js_State *J, const char *p, int *idx)

 {

-	char buf[32];

-	*idx = jsV_numbertointeger(jsV_stringtonumber(J, str));

-	sprintf(buf, "%u", *idx);

-	return !strcmp(buf, str);

+	int n = 0;

+	while (*p) {

+		int c = *p++;

+		if (c >= '0' && c <= '9') {

+			if (n > INT_MAX / 10 - 1)

+				return 0;

+			n = n * 10 + (c - '0');

+		} else {

+			return 0;

+		}

+	}

+	return *idx = n, 1;

 }

 static void js_pushrune(js_State *J, Rune rune)