From f74f280a14f9b79a25e2ba29bab7a3056c94e647 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 19 Oct 2011 14:51:12 +0200 Subject: get_header_tar: shrink 6->64 sign extension code function old new delta getOctal 125 107 -18 Signed-off-by: Denys Vlasenko --- archival/libarchive/get_header_tar.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/archival/libarchive/get_header_tar.c b/archival/libarchive/get_header_tar.c index 41e3efb50..a63c0fb01 100644 --- a/archival/libarchive/get_header_tar.c +++ b/archival/libarchive/get_header_tar.c @@ -79,10 +79,10 @@ static unsigned long long getOctal(char *str, int len) * * NB: tarballs with NEGATIVE unix times encoded that way were seen! */ - v = first; - /* Sign-extend using 6th bit: */ - v <<= sizeof(unsigned long long)*8 - 7; - v = (long long)v >> (sizeof(unsigned long long)*8 - 7); + /* Sign-extend 7bit 'first' to 64bit 'v' (that is, using 6th bit as sign): */ + first <<= 1; + first >>= 1; /* now 7th bit = 6th bit */ + v = first; /* sign-extend 8 bits to 64 */ while (--len != 0) v = (v << 8) + (unsigned char) *str++; } -- cgit v1.2.3