1 files changed, 101 insertions, 0 deletions
diff --git a/libmisc/getrange.c b/libmisc/getrange.c
new file mode 100644
index 0000000..82f2edf
--- /dev/null
+++ b/libmisc/getrange.c
@@ -0,0 +1,101 @@
+/*
+ * SPDX-FileCopyrightText: 2008       , Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <config.h>
+
+#ident "$Id: $"
+
+#include <ctype.h>
+#include <stdlib.h>
+
+#include "defines.h"
+#include "prototypes.h"
+
+/*
+ * Parse a range and indicate if the range is valid.
+ * Valid ranges are in the form:
+ *     <long>          -> min=max=long         has_min  has_max
+ *     -<long>         -> max=long            !has_min  has_max
+ *     <long>-         -> min=long             has_min !has_max
+ *     <long1>-<long2> -> min=long1 max=long2  has_min  has_max
+ *
+ * If the range is valid, getrange returns 1.
+ * If the range is not valid, getrange returns 0.
+ */
+int getrange (const char *range,
+              unsigned long *min, bool *has_min,
+              unsigned long *max, bool *has_max)
+{
+	char *endptr;
+	unsigned long n;
+
+	if (NULL == range) {
+		return 0;
+	}
+
+	if ('-' == range[0]) {
+		if (!isdigit(range[1])) {
+			/* invalid */
+			return 0;
+		}
+		errno = 0;
+		n = strtoul (&range[1], &endptr, 10);
+		if (('\0' != *endptr) || (ERANGE == errno)) {
+			/* invalid */
+			return 0;
+		}
+		/* -<long> */
+		*has_min = false;
+		*has_max = true;
+		*max = n;
+	} else {
+		errno = 0;
+		n = strtoul (range, &endptr, 10);
+		if (ERANGE == errno) {
+			/* invalid */
+			return 0;
+		}
+		switch (*endptr) {
+			case '\0':
+				/* <long> */
+				*has_min = true;
+				*has_max = true;
+				*min = n;
+				*max = n;
+				break;
+			case '-':
+				endptr++;
+				if ('\0' == *endptr) {
+					/* <long>- */
+					*has_min = true;
+					*has_max = false;
+					*min = n;
+				} else if (!isdigit (*endptr)) {
+					/* invalid */
+					return 0;
+				} else {
+					*has_min = true;
+					*min = n;
+					errno = 0;
+					n = strtoul (endptr, &endptr, 10);
+					if (   ('\0' != *endptr)
+					    || (ERANGE == errno)) {
+						/* invalid */
+						return 0;
+					}
+					/* <long>-<long> */
+					*has_max = true;
+					*max = n;
+				}
+				break;
+			default:
+				return 0;
+		}
+	}
+
+	return 1;
+}
+