>From 3d6c193d5fb1e4e6022f976437caf01fdef68ee8 Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <address@hidden>
Date: Wed, 6 Nov 2019 11:13:02 +0100
Subject: [PATCH] ustar: fix prefix length calculation in split_long_name

This is backport of cd91cd3c629e3c489e5ab4650f443cdcfeec670a from
GNU tar.

* src/tar.c (split_long_name): Fix prefix length
calculation.
---
 src/tar.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/tar.c b/src/tar.c
index 07abfcd..99ef8a2 100644
--- a/src/tar.c
+++ b/src/tar.c
@@ -48,10 +48,12 @@ split_long_name (const char *name, size_t length)
 {
   size_t i;
 
-  if (length > TARPREFIXSIZE)
-    length = TARPREFIXSIZE+2;
+  if (length > TARPREFIXSIZE + 1)
+    length = TARPREFIXSIZE + 1;
+  else if (ISSLASH (name[length - 1]))
+    length--;
   for (i = length - 1; i > 0; i--)
-    if (name[i] == '/')
+    if (ISSLASH (name[i]))
       break;
   return i;
 }
-- 
2.23.0