1 files changed, 111 insertions, 0 deletions
diff --git a/include/optutils.h b/include/optutils.h
new file mode 100644
index 0000000..6fe4aeb
--- /dev/null
+++ b/include/optutils.h
@@ -0,0 +1,111 @@
+/*
+ * No copyright is claimed.  This code is in the public domain; do with
+ * it what you wish.
+ */
+#ifndef UTIL_LINUX_OPTUTILS_H
+#define UTIL_LINUX_OPTUTILS_H
+
+#include <assert.h>
+
+#include "c.h"
+#include "nls.h"
+#include "cctype.h"
+
+static inline const char *option_to_longopt(int c, const struct option *opts)
+{
+	const struct option *o;
+
+	assert(!(opts == NULL));
+	for (o = opts; o->name; o++)
+		if (o->val == c)
+			return o->name;
+	return NULL;
+}
+
+#ifndef OPTUTILS_EXIT_CODE
+# define OPTUTILS_EXIT_CODE EXIT_FAILURE
+#endif
+
+/*
+ * Check collisions between options.
+ *
+ * The conflicts between options are described in ul_excl_t array. The
+ * array contains groups of mutually exclusive options. For example
+ *
+ *	static const ul_excl_t excl[] = {
+ *		{ 'Z','b','c' },		// first group
+ *		{ 'b','x' },			// second group
+ *		{ 0 }
+ *	};
+ *
+ *	int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+ *
+ *	while ((c = getopt_long(argc, argv, "Zbcx", longopts, NULL)) != -1) {
+ *
+ *		err_exclusive_options(c, longopts, excl, excl_st);
+ *
+ *		switch (c) {
+ *		case 'Z':
+ *		   ....
+ *		}
+ *	}
+ *
+ * The array excl[] defines two groups of the mutually exclusive options. The
+ * option '-b' is in the both groups.
+ *
+ * Note that the options in the group have to be in ASCII order (ABC..abc..) and
+ * groups have to be also in ASCII order.
+ *
+ * The maximal number of the options in the group is 15 (size of the array is
+ * 16, last is zero).
+ *
+ * The current status of options is stored in excl_st array. The size of the array
+ * must be the same as number of the groups in the ul_excl_t array.
+ *
+ * If you're unsure then see sys-utils/mount.c or misc-utils/findmnt.c.
+ */
+#define UL_EXCL_STATUS_INIT	{ 0 }
+typedef int ul_excl_t[16];
+
+static inline void err_exclusive_options(
+			int c,
+			const struct option *opts,
+			const ul_excl_t *excl,
+			int *status)
+{
+	int e;
+
+	for (e = 0; excl[e][0] && excl[e][0] <= c; e++) {
+		const int *op = excl[e];
+
+		for (; *op && *op <= c; op++) {
+			if (*op != c)
+				continue;
+			if (status[e] == 0)
+				status[e] = c;
+			else if (status[e] != c) {
+				size_t ct = 0;
+
+				fprintf(stderr, _("%s: mutually exclusive "
+						  "arguments:"),
+						program_invocation_short_name);
+
+				for (op = excl[e];
+				     ct + 1 < ARRAY_SIZE(excl[0]) && *op;
+				     op++, ct++) {
+					const char *n = option_to_longopt(*op, opts);
+					if (n)
+						fprintf(stderr, " --%s", n);
+					else if (c_isgraph(*op))
+						fprintf(stderr, " -%c", *op);
+				}
+				fputc('\n', stderr);
+				exit(OPTUTILS_EXIT_CODE);
+			}
+			break;
+		}
+	}
+}
+
+#endif
+