From: Guy Harris <guy@alum.mit.edu>
Date: Sun, 9 Aug 2015 18:04:53 +0000 (-0700)
Subject: Clean up signed_relts_print() some more.
X-Git-Tag: tcpdump-4.9.0-bp~73
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/4e85180c53c1c8992c2979f6ad0ba4375c02203d

Clean up signed_relts_print() some more.

If it's not < 0, it's not -2147483648; check for negative values first.

Don't calculate the value for -2147483648 by hand, print a - and then
have unsigned_relts_print() calculate the value for 2147483648.
---

diff --git a/util-print.c b/util-print.c
index d0f014fd..68f98887 100644
--- a/util-print.c
+++ b/util-print.c
@@ -423,22 +423,29 @@ void
 signed_relts_print(netdissect_options *ndo,
                    int32_t secs)
 {
-	if (secs == -2147483648) {
-		/*
-		 * -2^31; you can't fit its absolute value into a 32-bit
-		 * signed integer.
-		 *
-		 * We calculate the right string by hand.
-		 */
-		ND_PRINT((ndo, "-68y5w3h14m8s"));
-		return;
-	}
 	if (secs < 0) {
-		/*
-		 * We now know -secs will fit into secs.
-		 */
 		ND_PRINT((ndo, "-"));
-		secs = -secs;
+		if (secs == -2147483648) {
+			/*
+			 * -2^31; you can't fit its absolute value into
+			 * a 32-bit signed integer.
+			 *
+			 * Just directly pass said absolute value to
+			 * unsigned_relts_print() directly.
+			 *
+			 * (XXX - does ISO C guarantee that -(-2^n),
+			 * when calculated and cast to an n-bit unsigned
+			 * integer type, will have the value 2^n?)
+			 */
+			unsigned_relts_print(ndo, 2147483648U);
+		} else {
+			/*
+			 * We now know -secs will fit into an int32_t;
+			 * negate it and pass that to unsigned_relts_print().
+			 */
+			unsigned_relts_print(ndo, -secs);
+		}
+		return;
 	}
 	unsigned_relts_print(ndo, secs);
 }