Make NULL a (void*)0 whereever possible, and fix the warnings(-Werror)

that this provokes. "Wherever possible" means "In the kernel OR NOT
C++" (implying C).

There are places where (void *) pointers are not valid, such as for
function pointers, but in the special case of (void *)0, agreement
settles on it being OK.

Most of the fixes were NULL where an integer zero was needed; many
of the fixes were NULL where ascii <nul> ('\0') was needed, and a
few were just "other".

Tested on: i386 sparc64

5 files changed, 6 insertions, 6 deletions

diff --git a/sbin/atm/atmconfig/diag.c b/sbin/atm/atmconfig/diag.c
index 733c879..bd8bc7e 100644
--- a/sbin/atm/atmconfig/diag.c
+++ b/sbin/atm/atmconfig/diag.c
@@ -232,7 +232,7 @@ phy_fetch(const char *ifname, const char *var, void *val, size_t len,
 
 	if (asprintf(&str, "hw.atm.%s.phy_%s", ifname, var) == -1)
 		err(1, NULL);
-	if (sysctlbyname(str, val, &len, NULL, NULL) == -1) {
+	if (sysctlbyname(str, val, &len, NULL, 0) == -1) {
 		if (err_fatal || errno != ENOENT)
 			err(1, "%s", str);
 		free(str);
diff --git a/sbin/kldconfig/kldconfig.c b/sbin/kldconfig/kldconfig.c
index 0f7c721..1f53d7c 100644
--- a/sbin/kldconfig/kldconfig.c
+++ b/sbin/kldconfig/kldconfig.c
@@ -113,14 +113,14 @@ getpath(void)
 
 	if (miblen == 0)
 		getmib();
-	if (sysctl(mib, miblen, NULL, &sz, NULL, NULL) == -1)
+	if (sysctl(mib, miblen, NULL, &sz, NULL, 0) == -1)
 		err(1, "getting path: sysctl(%s) - size only", pathctl);
 	if ((path = malloc(sz + 1)) == NULL) {
 		errno = ENOMEM;
 		err(1, "allocating %lu bytes for the path",
 		    (unsigned long)sz+1);
 	}
-	if (sysctl(mib, miblen, path, &sz, NULL, NULL) == -1)
+	if (sysctl(mib, miblen, path, &sz, NULL, 0) == -1)
 		err(1, "getting path: sysctl(%s)", pathctl);
 	modpath = path;
 }
diff --git a/sbin/raidctl/raidctl.c b/sbin/raidctl/raidctl.c
index 4b7d27d..117e651 100644
--- a/sbin/raidctl/raidctl.c
+++ b/sbin/raidctl/raidctl.c
@@ -272,7 +272,7 @@ main(argc,argv)
 	argc -= optind;
 	argv += optind;
 
-	if ((num_options > 1) || (argc == NULL)) 
+	if ((num_options > 1) || (argc == 0)) 
 		usage();
 
 	strncpy(name,argv[0],PATH_MAX);
diff --git a/sbin/raidctl/rf_configure.c b/sbin/raidctl/rf_configure.c
index 8df7889..2970467 100644
--- a/sbin/raidctl/rf_configure.c
+++ b/sbin/raidctl/rf_configure.c
@@ -249,7 +249,7 @@ rf_MakeConfig(configname, cfgPtr)
 			}
 			/* Get rid of the newline at the end of the string */
 			if ((bfr1 = strchr(&bfr[0], '\n')) != NULL)
-				*bfr1 = NULL;
+				*bfr1 = '\0';
 			/* Make sure the device exists */
 			if ((devfd = open(&bfr[0], O_RDWR)) < 0) {
 				RF_ERRORMSG2(
diff --git a/sbin/swapon/swapon.c b/sbin/swapon/swapon.c
index 063eff4..edcc998 100644
--- a/sbin/swapon/swapon.c
+++ b/sbin/swapon/swapon.c
@@ -254,7 +254,7 @@ swaplist(int lflag, int sflag, int hflag)
 	for (n = 0; ; ++n) {
 		mib[mibsize] = n;
 		size = sizeof xsw;
-		if (sysctl(mib, mibsize + 1, &xsw, &size, NULL, NULL) == -1)
+		if (sysctl(mib, mibsize + 1, &xsw, &size, NULL, 0) == -1)
 			break;
 		if (xsw.xsw_version != XSWDEV_VERSION)
 			errx(1, "xswdev version mismatch");