Re: usr/bin/ktrace: replace snprintf(3)/write(2) with #define and write(2)

[Adam Wolk]

On Sun, Jun 11, 2017 at 11:10:30AM -0600, Theo de Raadt wrote:
> +       write(STDERR_FILENO, NO_KTRACE, sizeof(NO_KTRACE));
> 
> Naw, I dislike that sizeof.
> 
> You can use dprintf, it is signal-safe in OpenBSD as long as the format
> string doesn't contain floating-point strings.

Attaching updated diff.


? ktrace
? ktrace.1.diff
? ktrace.diff
Index: ktrace.c
===================================================================
RCS file: /cvs/src/usr.bin/ktrace/ktrace.c,v
retrieving revision 1.33
diff -u -p -r1.33 ktrace.c
--- ktrace.c    18 Jul 2016 09:36:50 -0000      1.33
+++ ktrace.c    11 Jun 2017 17:17:59 -0000
@@ -250,10 +250,7 @@ usage(void)
 static void
 no_ktrace(int signo)
 {
-       char buf[8192];
-
-       snprintf(buf, sizeof(buf),
+       dprintf(STDERR_FILENO,
 "error:\tktrace() system call not supported in the running 
kernel\n\tre-compile kernel with 'option KTRACE'\n");
-       write(STDERR_FILENO, buf, strlen(buf));
        _exit(1);
 }