Provide Musl derived fallbacks for getopt/getopt_long/getsubopt

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 96 insertions, 0 deletions

diff --git a/lib/compat/getopt.c b/lib/compat/getopt.c
new file mode 100644
index 0000000..9876a87
--- /dev/null
+++ b/lib/compat/getopt.c
@@ -0,0 +1,96 @@
+#include "compat.h"
+
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+#include <stdlib.h>
+
+#ifndef HAVE_GETOPT
+char *optarg;
+int optind=1, opterr=1, optopt, optpos, optreset=0;
+
+void __getopt_msg(const char *a, const char *b, const char *c, size_t l)
+{
+	fputs(a, stderr);
+	fwrite(b, strlen(b), 1, stderr);
+	fwrite(c, 1, l, stderr);
+	putc('\n', stderr);
+}
+
+int getopt(int argc, char * const argv[], const char *optstring)
+{
+	int i;
+	wchar_t c, d;
+	int k, l;
+	char *optchar;
+
+	if (!optind || __optreset) {
+		optreset = 0;
+		optpos = 0;
+		optind = 1;
+	}
+
+	if (optind >= argc || !argv[optind])
+		return -1;
+
+	if (argv[optind][0] != '-') {
+		if (optstring[0] == '-') {
+			optarg = argv[optind++];
+			return 1;
+		}
+		return -1;
+	}
+
+	if (!argv[optind][1])
+		return -1;
+
+	if (argv[optind][1] == '-' && !argv[optind][2])
+		return optind++, -1;
+
+	if (!optpos) optpos++;
+	if ((k = mbtowc(&c, argv[optind]+optpos, MB_LEN_MAX)) < 0) {
+		k = 1;
+		c = 0xfffd; /* replacement char */
+	}
+	optchar = argv[optind]+optpos;
+	optpos += k;
+
+	if (!argv[optind][optpos]) {
+		optind++;
+		optpos = 0;
+	}
+
+	if (optstring[0] == '-' || optstring[0] == '+')
+		optstring++;
+
+	i = 0;
+	d = 0;
+	do {
+		l = mbtowc(&d, optstring+i, MB_LEN_MAX);
+		if (l>0) i+=l; else i++;
+	} while (l && d != c);
+
+	if (d != c || c == ':') {
+		optopt = c;
+		if (optstring[0] != ':' && opterr)
+			__getopt_msg(argv[0], ": unrecognized option: ", optchar, k);
+		return '?';
+	}
+	if (optstring[i] == ':') {
+		optarg = 0;
+		if (optstring[i+1] != ':' || optpos) {
+			optarg = argv[optind++] + optpos;
+			optpos = 0;
+		}
+		if (optind > argc) {
+			optopt = c;
+			if (optstring[0] == ':') return ':';
+			if (opterr) __getopt_msg(argv[0],
+				": option requires an argument: ",
+				optchar, k);
+			return '?';
+		}
+	}
+	return c;
+}
+#endif