Fix a number of warnings. A gcc preprocessor bug relating to macros

with variable numbers of arguments made this slightly harder than
it should be. Avoid the bug by not doing string concatenation within
the macros, and instead add a new function to syslog or print the
error messages.

usr.sbin/moused/moused.c

@@ -68,6 +68,7 @@ static const char rcsid[] =
 #include <sys/types.h>
 #include <sys/time.h>
 #include <sys/socket.h>
+#include <sys/stat.h>
 #include <sys/un.h>
 #include <unistd.h>
 
@@ -104,38 +105,26 @@ static const char rcsid[] =
 #define ID_MODEL	8
 #define ID_ALL		(ID_PORT | ID_IF | ID_TYPE | ID_MODEL)
 
-#define debug(fmt,args...) \
-	if (debug&&nodaemon) warnx(fmt, ##args)
+#define debug(fmt, args...) do {				\
+	if (debug && nodaemon)					\
+		warnx(fmt, ##args);				\
+} while (0)
 
-#define logerr(e, fmt, args...) {				\
-	if (background) {					\
-	    syslog(LOG_DAEMON | LOG_ERR, fmt ": %m", ##args);	\
-	    exit(e);						\
-	} else							\
-	    err(e, fmt, ##args);				\
-}
+#define logerr(e, fmt, args...) do {				\
+	log_or_warn(LOG_DAEMON | LOG_ERR, errno, fmt, ##args);	\
+	exit(e);						\
+} while (0)
 
-#define logerrx(e, fmt, args...) {				\
-	if (background) {					\
-	    syslog(LOG_DAEMON | LOG_ERR, fmt, ##args);		\
-	    exit(e);						\
-	} else							\
-	    errx(e, fmt, ##args);				\
-}
+#define logerrx(e, fmt, args...) do {				\
+	log_or_warn(LOG_DAEMON | LOG_ERR, 0, fmt, ##args);	\
+	exit(e);						\
+} while (0)
 
-#define logwarn(fmt, args...) {					\
-	if (background)						\
-	    syslog(LOG_DAEMON | LOG_WARNING, fmt ": %m", ##args); \
-	else							\
-	    warn(fmt, ##args);					\
-}
+#define logwarn(fmt, args...)					\
+	log_or_warn(LOG_DAEMON | LOG_WARNING, errno, fmt, ##args)
 
-#define logwarnx(fmt, args...) {				\
-	if (background)						\
-	    syslog(LOG_DAEMON | LOG_WARNING, fmt, ##args);	\
-	else							\
-	    warnx(fmt, ##args);					\
-}
+#define logwarnx(fmt, args...)					\
+	log_or_warn(LOG_DAEMON | LOG_WARNING, 0, fmt, ##args)
 
 /* structures */
 
@@ -475,6 +464,8 @@ static void	moused(void);
 static void	hup(int sig);
 static void	cleanup(int sig);
 static void	usage(void);
+static void	log_or_warn(int log_pri, int errnum, const char *fmt, ...)
+		    __printflike(3, 4);
 
 static int	r_identify(void);
 static char	*r_if(int type);
@@ -838,11 +829,11 @@ moused(void)
     int i;
 
     if ((rodent.cfd = open("/dev/consolectl", O_RDWR, 0)) == -1)
-	logerr(1, "cannot open /dev/consolectl", 0);
+	logerr(1, "cannot open /dev/consolectl");
 
-    if (!nodaemon && !background)
+    if (!nodaemon && !background) {
 	if (daemon(0, 0)) {
-	    logerr(1, "failed to become a daemon", 0);
+	    logerr(1, "failed to become a daemon");
 	} else {
 	    background = TRUE;
 	    fp = fopen(pidfile, "w");
@@ -851,6 +842,7 @@ moused(void)
 		fclose(fp);
 	    }
 	}
+    }
 
     /* clear mouse data */
     bzero(&action0, sizeof(action0));
@@ -888,7 +880,7 @@ moused(void)
 	c = select(FD_SETSIZE, &fds, NULL, NULL,
 		   (rodent.flags & Emulate3Button) ? &timeout : NULL);
 	if (c < 0) {                    /* error */
-	    logwarn("failed to read from mouse", 0);
+	    logwarn("failed to read from mouse");
 	    continue;
 	} else if (c == 0) {            /* timeout */
 	    /* assert(rodent.flags & Emulate3Button) */
@@ -1017,6 +1009,30 @@ usage(void)
     exit(1);
 }
 
+/*
+ * Output an error message to syslog or stderr as appropriate. If
+ * `errnum' is non-zero, append its string form to the message.
+ */
+static void
+log_or_warn(int log_pri, int errnum, const char *fmt, ...)
+{
+	va_list ap;
+	char buf[256];
+
+	va_start(ap, fmt);
+	vsnprintf(buf, sizeof(buf), fmt, ap);
+	va_end(ap);
+	if (errnum) {
+		strlcat(buf, ": ", sizeof(buf));
+		strlcat(buf, strerror(errnum), sizeof(buf));
+	}
+
+	if (background)
+		syslog(log_pri, "%s", buf);
+	else
+		warnx("%s", buf);
+}
+
 /**
  ** Mouse interface code, courtesy of XFree86 3.1.2.
  **
@@ -2304,7 +2320,7 @@ setmousespeed(int old, int new, unsigned cflag)
 
 	if (tcgetattr(rodent.mfd, &tty) < 0)
 	{
-		logwarn("unable to get status of mouse fd", 0);
+		logwarn("unable to get status of mouse fd");
 		return;
 	}
 
@@ -2337,7 +2353,7 @@ setmousespeed(int old, int new, unsigned cflag)
 
 	if (tcsetattr(rodent.mfd, TCSADRAIN, &tty) < 0)
 	{
-		logwarn("unable to set status of mouse fd", 0);
+		logwarn("unable to set status of mouse fd");
 		return;
 	}
 
@@ -2370,14 +2386,14 @@ setmousespeed(int old, int new, unsigned cflag)
 	{
 		if (write(rodent.mfd, c, 2) != 2)
 		{
-			logwarn("unable to write to mouse fd", 0);
+			logwarn("unable to write to mouse fd");
 			return;
 		}
 	}
 	usleep(100000);
 
 	if (tcsetattr(rodent.mfd, TCSADRAIN, &tty) < 0)
-		logwarn("unable to set status of mouse fd", 0);
+		logwarn("unable to set status of mouse fd");
 }
 
 /* 
@@ -2539,7 +2555,6 @@ pnpgets(char *buf)
 	 * assuming there is something at the port even if it didn't 
 	 * respond to the PnP enumeration procedure.
 	 */
-disconnect_idle:
 	i = TIOCM_DTR | TIOCM_RTS;		/* DTR = 1, RTS = 1 */
 	ioctl(rodent.mfd, TIOCMBIS, &i);
 	return 0;
@@ -2839,7 +2854,7 @@ typedef enum {
 static int
 kidspad(u_char rxc, mousestatus_t *act)
 {
-    static buf[5];
+    static int buf[5];
     static int buflen = 0, b_prev = 0 , x_prev = -1, y_prev = -1 ;
     static k_status status = S_IDLE ;
     static struct timeval old, now ;