From 753a1ada03bffcb3056b60b7a36587ac72379cbb Mon Sep 17 00:00:00 2001
From: deraadt <deraadt@openbsd.org>
Date: Fri, 8 Dec 2017 17:04:14 +0000
Subject: [PATCH] Convert snprintf+write into dprintf.  It is simply easier to
 read, and provides retry on short-write file descriptors. ok florian,
 previous versions seen by millert

---
 bin/pax/pax.c              | 11 +++--------
 sbin/dump/tape.c           |  7 +++----
 usr.bin/awk/lib.c          | 26 +++++++++-----------------
 usr.bin/chpass/chpass.c    | 18 +++---------------
 usr.bin/find/misc.c        | 12 +++---------
 usr.bin/login/login.c      |  7 ++-----
 usr.sbin/rtadvd/advcap.c   | 10 +++++-----
 usr.sbin/tcpdump/tcpdump.c | 14 +++++---------
 8 files changed, 33 insertions(+), 72 deletions(-)

diff --git a/bin/pax/pax.c b/bin/pax/pax.c
index ca46ba50ad6..91045afbfe5 100644
--- a/bin/pax/pax.c
+++ b/bin/pax/pax.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pax.c,v 1.50 2017/03/11 12:55:47 tb Exp $	*/
+/*	$OpenBSD: pax.c,v 1.51 2017/12/08 17:04:14 deraadt Exp $	*/
 /*	$NetBSD: pax.c,v 1.5 1996/03/26 23:54:20 mrg Exp $	*/
 
 /*-
@@ -311,8 +311,6 @@ main(int argc, char **argv)
 void
 sig_cleanup(int which_sig)
 {
-	char errbuf[80];
-
 	/*
 	 * restore modes and times for any dirs we may have created
 	 * or any dirs we may have read.
@@ -320,12 +318,9 @@ sig_cleanup(int which_sig)
 
 	/* paxwarn() uses stdio; fake it as well as we can */
 	if (which_sig == SIGXCPU)
-		strlcpy(errbuf, "\nCPU time limit reached, cleaning up.\n",
-		    sizeof errbuf);
+		dprintf(STDERR_FILENO, "\nCPU time limit reached, cleaning up.\n");
 	else
-		strlcpy(errbuf, "\nSignal caught, cleaning up.\n",
-		    sizeof errbuf);
-	(void) write(STDERR_FILENO, errbuf, strlen(errbuf));
+		dprintf(STDERR_FILENO, "\nSignal caught, cleaning up.\n");
 
 	ar_close(1);
 	sltab_process(1);
diff --git a/sbin/dump/tape.c b/sbin/dump/tape.c
index dc0eaf1d3bb..445a75df555 100644
--- a/sbin/dump/tape.c
+++ b/sbin/dump/tape.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tape.c,v 1.43 2015/08/20 22:02:20 deraadt Exp $	*/
+/*	$OpenBSD: tape.c,v 1.44 2017/12/08 17:04:15 deraadt Exp $	*/
 /*	$NetBSD: tape.c,v 1.11 1997/06/05 11:13:26 lukem Exp $	*/
 
 /*-
@@ -258,7 +258,6 @@ void
 statussig(int signo)
 {
 	time_t	tnow, deltat;
-	char	msgbuf[128];
 	int save_errno = errno;
 
 	if (blockswritten < 500)
@@ -266,12 +265,12 @@ statussig(int signo)
 	(void) time(&tnow);
 	deltat = tstart_writing - tnow + (1.0 * (tnow - tstart_writing))
 		/ blockswritten * tapesize;
-	(void)snprintf(msgbuf, sizeof(msgbuf),
+	/* XXX not safe due to floating point printf */
+	dprintf(STDERR_FILENO,
 	    "dump: %s %3.2f%% done at %lld KB/s, finished in %d:%02d\n",
 	    tape, (blockswritten * 100.0) / tapesize,
 	    (spcl.c_tapea - tapea_volume) / (tnow - tstart_volume),
 	    (int)(deltat / 3600), (int)((deltat % 3600) / 60));
-	write(STDERR_FILENO, msgbuf, strlen(msgbuf));
 	errno = save_errno;
 }
 
diff --git a/usr.bin/awk/lib.c b/usr.bin/awk/lib.c
index 2a40a02f6f3..f1ff64731ca 100644
--- a/usr.bin/awk/lib.c
+++ b/usr.bin/awk/lib.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lib.c,v 1.24 2017/10/09 14:51:31 deraadt Exp $	*/
+/*	$OpenBSD: lib.c,v 1.25 2017/12/08 17:04:15 deraadt Exp $	*/
 /****************************************************************
 Copyright (C) Lucent Technologies 1997
 All Rights Reserved
@@ -532,33 +532,25 @@ void SYNTAX(const char *fmt, ...)
 void fpecatch(int sig)
 {
 	extern Node *curnode;
-	char buf[1024];
 
-	snprintf(buf, sizeof buf, "floating point exception\n");
-	write(STDERR_FILENO, buf, strlen(buf));
+	dprintf(STDERR_FILENO, "floating point exception\n");
 
 	if (compile_time != 2 && NR && *NR > 0) {
-		snprintf(buf, sizeof buf, " input record number %d", (int) (*FNR));
-		write(STDERR_FILENO, buf, strlen(buf));
-
+		dprintf(STDERR_FILENO, " input record number %d", (int) (*FNR));
 		if (strcmp(*FILENAME, "-") != 0) {
-			snprintf(buf, sizeof buf, ", file %s", *FILENAME);
-			write(STDERR_FILENO, buf, strlen(buf));
+			dprintf(STDERR_FILENO, ", file %s", *FILENAME);
 		}
-		write(STDERR_FILENO, "\n", 1);
+		dprintf(STDERR_FILENO, "\n");
 	}
 	if (compile_time != 2 && curnode) {
-		snprintf(buf, sizeof buf, " source line number %d", curnode->lineno);
-		write(STDERR_FILENO, buf, strlen(buf));
+		dprintf(STDERR_FILENO, " source line number %d", curnode->lineno);
 	} else if (compile_time != 2 && lineno) {
-		snprintf(buf, sizeof buf, " source line number %d", lineno);
-		write(STDERR_FILENO, buf, strlen(buf));
+		dprintf(STDERR_FILENO, " source line number %d", lineno);
 	}
 	if (compile_time == 1 && cursource() != NULL) {
-		snprintf(buf, sizeof buf, " source file %s", cursource());
-		write(STDERR_FILENO, buf, strlen(buf));
+		dprintf(STDERR_FILENO, " source file %s", cursource());
 	}
-	write(STDERR_FILENO, "\n", 1);
+	dprintf(STDERR_FILENO, "\n");
 	if (dbg > 1)		/* core dump if serious debugging on */
 		abort();
 	_exit(1);
diff --git a/usr.bin/chpass/chpass.c b/usr.bin/chpass/chpass.c
index 4e47a82b441..1c1836c800a 100644
--- a/usr.bin/chpass/chpass.c
+++ b/usr.bin/chpass/chpass.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: chpass.c,v 1.43 2015/11/26 19:01:47 deraadt Exp $	*/
+/*	$OpenBSD: chpass.c,v 1.44 2017/12/08 17:04:15 deraadt Exp $	*/
 /*	$NetBSD: chpass.c,v 1.8 1996/05/15 21:50:43 jtc Exp $	*/
 
 /*-
@@ -219,20 +219,8 @@ baduser(void)
 void
 kbintr(int signo)
 {
-	struct iovec iv[5];
-
-	iv[0].iov_base = "\n";
-	iv[0].iov_len = 1;
-	iv[1].iov_base = __progname;
-	iv[1].iov_len = strlen(__progname);
-	iv[2].iov_base = ": ";
-	iv[2].iov_len = 2;
-	iv[3].iov_base = _PATH_MASTERPASSWD;
-	iv[3].iov_len = sizeof(_PATH_MASTERPASSWD) - 1;
-	iv[4].iov_base = " unchanged\n";
-	iv[4].iov_len = 11;
-	writev(STDERR_FILENO, iv, 5);
-
+	dprintf(STDERR_FILENO, "\n%s: %s unchanged\n",
+	    __progname, _PATH_MASTERPASSWD);
 	_exit(1);
 }
 
diff --git a/usr.bin/find/misc.c b/usr.bin/find/misc.c
index c4f358cadfd..69a4434bd4e 100644
--- a/usr.bin/find/misc.c
+++ b/usr.bin/find/misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: misc.c,v 1.15 2015/07/14 17:18:48 millert Exp $	*/
+/*	$OpenBSD: misc.c,v 1.16 2017/12/08 17:04:15 deraadt Exp $	*/
 
 /*-
  * Copyright (c) 1990, 1993
@@ -148,16 +148,10 @@ show_path(int signo)
 {
 	int save_errno = errno;
 	extern FTSENT *entry;
-	struct iovec iov[3];
 
 	if (entry != NULL) {
-		iov[0].iov_base = "find path: ";
-		iov[0].iov_len = strlen(iov[0].iov_base);
-		iov[1].iov_base = entry->fts_path;
-		iov[1].iov_len = entry->fts_pathlen;
-		iov[2].iov_base = "\n";
-		iov[2].iov_len = strlen(iov[2].iov_base);
-		writev(STDERR_FILENO, iov, 3);
+		dprintf(STDERR_FILENO, "find path: %*s\n",
+		    entry->fts_pathlen, entry->fts_path);
 		errno = save_errno;
 	}
 }
diff --git a/usr.bin/login/login.c b/usr.bin/login/login.c
index 9755972b443..edbb4d48c87 100644
--- a/usr.bin/login/login.c
+++ b/usr.bin/login/login.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: login.c,v 1.68 2016/08/21 03:26:04 beck Exp $	*/
+/*	$OpenBSD: login.c,v 1.69 2017/12/08 17:04:15 deraadt Exp $	*/
 /*	$NetBSD: login.c,v 1.13 1996/05/15 23:50:16 jtc Exp $	*/
 
 /*-
@@ -825,11 +825,8 @@ sigint(int signo)
 void
 timedout(int signo)
 {
-	char warn[1024];
-
-	snprintf(warn, sizeof warn,
+	dprintf(STDERR_FILENO,
 	    "Login timed out after %d seconds\n", timeout);
-	write(STDERR_FILENO, warn, strlen(warn));
 	if (username)
 		badlogin(username);
 	_exit(0);
diff --git a/usr.sbin/rtadvd/advcap.c b/usr.sbin/rtadvd/advcap.c
index 9b2cf3a19ec..ace81f4fa7c 100644
--- a/usr.sbin/rtadvd/advcap.c
+++ b/usr.sbin/rtadvd/advcap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: advcap.c,v 1.17 2015/10/25 22:36:17 jca Exp $	*/
+/*	$OpenBSD: advcap.c,v 1.18 2017/12/08 17:04:15 deraadt Exp $	*/
 /*	$KAME: advcap.c,v 1.9 2002/05/29 14:28:35 itojun Exp $	*/
 
 /*
@@ -151,7 +151,7 @@ getent(char *bp, char *name, char *cp)
 				break;
 			}
 			if (cp >= bp + BUFSIZ) {
-				write(STDERR_FILENO, "Remcap entry too long\n", 23);
+				dprintf(STDERR_FILENO, "Remcap entry too long\n");
 				break;
 			} else
 				*cp++ = c;
@@ -187,7 +187,7 @@ tnchktc(void)
 	p = tbuf + strlen(tbuf) - 2;	/* before the last colon */
 	while (*--p != ':')
 		if (p < tbuf) {
-			write(STDERR_FILENO, "Bad remcap entry\n", 18);
+			dprintf(STDERR_FILENO, "Bad remcap entry\n");
 			return (0);
 		}
 	p++;
@@ -200,7 +200,7 @@ tnchktc(void)
 		q++;
 	*q = 0;
 	if (++hopcount > MAXHOP) {
-		write(STDERR_FILENO, "Infinite tc= loop\n", 18);
+		dprintf(STDERR_FILENO, "Infinite tc= loop\n");
 		return (0);
 	}
 	if (getent(tcbuf, tcname, remotefile) != 1) {
@@ -212,7 +212,7 @@ tnchktc(void)
 		;
 	l = p - holdtbuf + strlen(q);
 	if (l > BUFSIZ) {
-		write(STDERR_FILENO, "Remcap entry too long\n", 23);
+		dprintf(STDERR_FILENO, "Remcap entry too long\n");
 		q[BUFSIZ - (p-holdtbuf)] = 0;
 	}
 	strlcpy(p, q, holdtbuf + BUFSIZ - p);
diff --git a/usr.sbin/tcpdump/tcpdump.c b/usr.sbin/tcpdump/tcpdump.c
index d90fd45d7b8..378d1574edb 100644
--- a/usr.sbin/tcpdump/tcpdump.c
+++ b/usr.sbin/tcpdump/tcpdump.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tcpdump.c,v 1.80 2017/09/08 19:10:57 brynet Exp $	*/
+/*	$OpenBSD: tcpdump.c,v 1.81 2017/12/08 17:04:15 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -513,25 +513,21 @@ cleanup(int signo)
 {
 	struct pcap_stat stat;
 	sigset_t allsigs;
-	char buf[1024];
 
 	sigfillset(&allsigs);
 	sigprocmask(SIG_BLOCK, &allsigs, NULL);
 
 	/* Can't print the summary if reading from a savefile */
-	(void)write(STDERR_FILENO, "\n", 1);
+	dprintf(STDERR_FILENO, "\n");
 	if (pd != NULL && pcap_file(pd) == NULL) {
 		if (priv_pcap_stats(&stat) < 0) {
-			(void)snprintf(buf, sizeof buf,
+			dprintf(STDERR_FILENO,
 			    "pcap_stats: %s\n", pcap_geterr(pd));
-			write(STDERR_FILENO, buf, strlen(buf));
 		} else {
-			(void)snprintf(buf, sizeof buf,
+			dprintf(STDERR_FILENO,
 			    "%u packets received by filter\n", stat.ps_recv);
-			write(STDERR_FILENO, buf, strlen(buf));
-			(void)snprintf(buf, sizeof buf,
+			dprintf(STDERR_FILENO,
 			    "%u packets dropped by kernel\n", stat.ps_drop);
-			write(STDERR_FILENO, buf, strlen(buf));
 		}
 	}
 	_exit(0);
-- 
2.20.1