Date: Sat, 23 Jun 2001 15:13:10 +0300 From: Peter Pentchev <roam@orbitel.bg> To: arch@FreeBSD.org Cc: audit@FreeBSD.org Subject: patch for '%lld' handling in *scanf(3) Message-ID: <20010623151310.A497@ringworld.oblivion.bg>
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Hi,
scanf(3) does not understand %lld for 'long long', it only understands
%qd, and it treats %lld as plain %ld. printf(3) prints out %lld just fine.
The fix needed is just three lines of code, which have been in both NetBSD
and OpenBSD for some time.
Demonstration: the following program:
#include <sys/types.h>
#include <stdio.h>
int
main(void) {
quad_t x = 0xeFFFFFFFFFFFFFFe;
scanf("%lld", &x);
printf("%llx\n", x);
return (0);
}
Before:
[roam@freefall ~/c/misc/foo]$ ./foo7
5
efffffff00000005
[roam@freefall ~/c/misc/foo]$
After:
[roam@ringworld:v4 ~/c/misc/foo]$ ./foo7
5
5
[roam@ringworld:v4 ~/c/misc/foo]$
The patch is attached.
OK, so maybe this patch is not quite semantically correct; it tends
to assume that 'long long' is the same as 'quad', or at least, that
the programmer asked for 'quad' by using %lld. A 'real' fix would
be defining a LONGLONG flag for scanf().
G'luck,
Peter
--
When you are not looking at it, this sentence is in Spanish.
Index: src/lib/libc/stdio/vfscanf.c
===================================================================
RCS file: /home/ncvs/src/lib/libc/stdio/vfscanf.c,v
retrieving revision 1.16
diff -u -r1.16 vfscanf.c
--- src/lib/libc/stdio/vfscanf.c 2001/02/10 05:46:05 1.16
+++ src/lib/libc/stdio/vfscanf.c 2001/06/23 12:12:30
@@ -186,7 +186,12 @@
flags |= SUPPRESS;
goto again;
case 'l':
- flags |= LONG;
+ if (*fmt == 'l') {
+ fmt++;
+ flags |= QUAD;
+ } else {
+ flags |= LONG;
+ }
goto again;
case 'q':
flags |= QUAD;
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