Someone

void Info_SetValueForKey( char *s, const char *key, const char *value ) {
	char	newi[MAX_INFO_STRING];

	if ( strlen( s ) >= MAX_INFO_STRING ) {
		Com_Error( ERR_DROP, "Info_SetValueForKey: oversize infostring [%s] [%s] [%s]", s, key, value );
	}

	if (strchr (key, '\\') || strchr (value, '\\'))
	{
		Com_Printf ("Can't use keys or values with a \\\n");
		return;
	}

	if (strchr (key, ';') || strchr (value, ';'))
	{
		Com_Printf ("Can't use keys or values with a semicolon\n");
		return;
	}

	if (strchr (key, '\"') || strchr (value, '\"'))
	{
		Com_Printf ("Can't use keys or values with a \"\n");
		return;
	}

	Info_RemoveKey (s, key);
	if (!value || !strlen(value))
		return;

	Com_sprintf (newi, sizeof(newi), "\\%s\\%s", key, value);

	if (strlen(newi) + strlen(s) > MAX_INFO_STRING)
	{
		Com_Printf ("Info string length exceeded\n");
		return;
	}

	strcat (s, newi);
}