utils: add s32 parser

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>

include/utils.h

@@ -85,6 +85,7 @@ extern int get_time_rtt(unsigned *val, const char *arg, int *raw);
 #define get_short get_s16
 extern int get_u64(__u64 *val, const char *arg, int base);
 extern int get_u32(__u32 *val, const char *arg, int base);
+extern int get_s32(__s32 *val, const char *arg, int base);
 extern int get_u16(__u16 *val, const char *arg, int base);
 extern int get_s16(__s16 *val, const char *arg, int base);
 extern int get_u8(__u8 *val, const char *arg, int base);

lib/utils.c

@@ -25,6 +25,7 @@
 #include <linux/pkt_sched.h>
 #include <time.h>
 #include <sys/time.h>
+#include <errno.h>
 
 
 #include "utils.h"
@@ -198,6 +199,24 @@ int get_u8(__u8 *val, const char *arg, int base)
 	return 0;
 }
 
+int get_s32(__s32 *val, const char *arg, int base)
+{
+	long res;
+	char *ptr;
+
+	errno = 0;
+
+	if (!arg || !*arg)
+		return -1;
+	res = strtol(arg, &ptr, base);
+	if (ptr == arg || *ptr ||
+	    ((res ==  LONG_MIN || res == LONG_MAX) && errno == ERANGE) ||
+	    res > INT32_MAX || res < INT32_MIN)
+		return -1;
+	*val = res;
+	return 0;
+}
+
 int get_s16(__s16 *val, const char *arg, int base)
 {
 	long res;