1 files changed, 70 insertions, 0 deletions
diff --git a/lib/compat/getopt.c b/lib/compat/getopt.c
new file mode 100644
index 0000000..23ede4c
--- /dev/null
+++ b/lib/compat/getopt.c
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * getopt.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "compat.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+
+#ifndef HAVE_GETOPT
+static char *current = "";
+int optind = 1;
+char *optarg = NULL;
+
+int getopt(int argc, char *const argv[], const char *optstr)
+{
+	char optchr, *ptr;
+
+	if (*current == '\0') {
+		if (optind >= argc || argv[optind][0] != '-')
+			return -1;
+
+		if (argv[optind][1] == '-' && argv[optind][2] == '\0') {
+			++optind;
+			return -1;
+		}
+
+		if (argv[optind][1] == '\0')
+			return -1;
+
+		current = argv[optind] + 1;
+	}
+
+	optchr = *(current++);
+	if (optchr == ':' || (ptr = strchr(optstr, optchr)) == NULL)
+		goto fail_unknown;
+
+	if (ptr[1] == ':') {
+		if (*current != '\0') {
+			optarg = current;
+		} else {
+			if (++optind >= argc)
+				goto fail_arg;
+
+			optarg = argv[optind];
+		}
+
+		current = "";
+		++optind;
+	} else {
+		optarg = NULL;
+
+		if (*current == '\0')
+			++optind;
+	}
+
+	return optchr;
+fail_unknown:
+	fprintf(stderr, "%s: unknown option `-%c`\n", argv[0], optchr);
+	return '?';
+fail_arg:
+	fprintf(stderr, "%s: missing argument for option `-%c`\n",
+		argv[0], optchr);
+	return '?';
+}
+#endif