sdhcp

commit 19e0ab7cc747ad5f6f239e484531a5fec0626e14
parent 8559ac1f08e7592d9f9b142e11125e210d6e7f5b
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Fri, 25 Apr 2014 21:50:25 +0200

add eprintf(), weprintf()

use it instead of die()

Signed-off-by: Hiltjo Posthuma <hiltjo@codemadness.org>

Diffstat:
M
Makefile
 | 
5
+++--
M
sdhcp.c
 | 
20
++++++++++++--------
M
util.h
 | 
4
++++
A
util/eprintf.c
 | 
67
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

4 files changed, 86 insertions(+), 10 deletions(-)
diff --git a/Makefile b/Makefile
@@ -3,9 +3,10 @@ include config.mk
 .POSIX:
 .SUFFIXES: .c .o
 
-HDR = util.h
+HDR = util.h arg.h
 LIB = \
-	  util/strlcpy.o
+	util/strlcpy.o \
+	util/eprintf.o
 
 SRC = sdhcp.c
 
diff --git a/sdhcp.c b/sdhcp.c
@@ -194,8 +194,10 @@ static void
 setdns(unsigned char dns[4])
 {
 	char buf[128], *bp = buf;
-	int fd = creat("/etc/resolv.conf", 0644);
+	int fd;
 
+	if((fd = creat("/etca/resolv.conf", 0644)) == -1)
+		weprintf("can't change /etc/resolv.conf:");
 	cat(fd, "/etc/resolv.conf.head");
 	memcpy(buf, "\nnameserver ", 12), bp+=11;
 	*(bp = itoa(bp+1, dns[0])) = '.';
@@ -441,20 +443,22 @@ main(int argc, char *argv[])
 	signal(SIGTERM, cleanexit);
 
 	if((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
-		die("socket");
+		eprintf("socket:");
 	if(setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &bcast, sizeof bcast) == -1)
-		die("setsockopt");
+		eprintf("setsockopt:");
 
 	strlcpy(ifreq.ifr_name, ifname, IF_NAMESIZE);
 	ioctl(sock, SIOCGIFINDEX, &ifreq);
 	if(setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, &ifreq, sizeof ifreq) == -1)
-		die("setsockopt");
-	addr = iptoaddr(IP(255,255,255,255), 68);
-	if(bind(sock, (void*)&addr, sizeof addr)!=0)
-		die("bind");
+		eprintf("setsockopt:");
+	addr = iptoaddr(IP(255, 255, 255, 255), 68);
+	if(bind(sock, (void*)&addr, sizeof addr) != 0)
+		eprintf("bind:");
 	ioctl(sock, SIOCGIFHWADDR, &ifreq);
 	memcpy(hwaddr, ifreq.ifr_hwaddr.sa_data, sizeof ifreq.ifr_hwaddr.sa_data);
-	rnd = open("/dev/urandom", O_RDONLY);
+
+	if((rnd = open("/dev/urandom", O_RDONLY) == -1))
+		eprintf("can't open /dev/urandom to generate unique transaction identifier:");
 	read(rnd, xid, sizeof xid);
 	close(rnd);
 
diff --git a/util.h b/util.h
@@ -3,3 +3,7 @@
 
 #undef strlcpy
 size_t strlcpy(char *, const char *, size_t);
+
+void weprintf(const char *, ...);
+void eprintf(const char *, ...);
+void enprintf(int, const char *, ...);
diff --git a/util/eprintf.c b/util/eprintf.c
@@ -0,0 +1,67 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "../util.h"
+
+char *argv0;
+
+static void venprintf(int, const char *, va_list);
+
+void
+eprintf(const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	venprintf(EXIT_FAILURE, fmt, ap);
+	va_end(ap);
+}
+
+void
+enprintf(int status, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	venprintf(status, fmt, ap);
+	va_end(ap);
+}
+
+void
+venprintf(int status, const char *fmt, va_list ap)
+{
+#ifdef DEBUG
+	fprintf(stderr, "%s: ", argv0);
+#endif
+
+	vfprintf(stderr, fmt, ap);
+
+	if(fmt[0] && fmt[strlen(fmt)-1] == ':') {
+		fputc(' ', stderr);
+		perror(NULL);
+	}
+
+	exit(status);
+}
+
+void
+weprintf(const char *fmt, ...)
+{
+	va_list ap;
+
+#ifdef DEBUG
+	fprintf(stderr, "%s: ", argv0);
+#endif
+
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	if (fmt[0] && fmt[strlen(fmt)-1] == ':') {
+		fputc(' ', stderr);
+		perror(NULL);
+	}
+}