+int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
+{
+ char c, *eq;
+ int len;
+
+ if (*arg != '-')
+ return 0;
+ c = *++arg;
+ if (!c)
+ return 0;
+ if (c == arg_short) {
+ c = *++arg;
+ if (!c)
+ return 1;
+ if (val && isdigit(c)) {
+ char *end;
+ int n = strtoul(arg, &end, 10);
+ if (*end)
+ return 0;
+ *val = n;
+ return 1;
+ }
+ return 0;
+ }
+ if (c != '-')
+ return 0;
+ arg++;
+ eq = strchr(arg, '=');
+ if (eq)
+ len = eq - arg;
+ else
+ len = strlen(arg);
+ if (!len || strncmp(arg, arg_long, len))
+ return 0;
+ if (eq) {
+ int n;
+ char *end;
+ if (!isdigit(*++eq))
+ return 0;
+ n = strtoul(eq, &end, 10);
+ if (*end)
+ return 0;
+ *val = n;
+ }
+ return 1;
+}
+