Simplify string handling

lib/env.c

@@ -226,9 +226,9 @@ void sanitize_env (void)
 			if (!strprefix(*cur, *bad)) {
 				continue;
 			}
-			if (strchr (*cur, '/') == NULL) {
+			if (!strchr(*cur, '/'))
 				continue;	/* OK */
-			}
+
 			for (move = cur; NULL != *move; move++) {
 				*move = *(move + 1);
 			}

lib/obscure.c

@@ -13,6 +13,7 @@
 
 #include <ctype.h>
 #include <stdio.h>
+#include <string.h>
 
 #include "attr.h"
 #include "prototypes.h"
@@ -66,9 +67,8 @@ static bool similar (/*@notnull@*/const char *old, /*@notnull@*/const char *new)
 	}
 
 	for (i = j = 0; ('\0' != new[i]) && ('\0' != old[i]); i++) {
-		if (strchr (new, old[i]) != NULL) {
+		if (strchr(new, old[i]))
 			j++;
-		}
 	}
 
 	if (i >= j * 2) {

lib/setupenv.c

@@ -235,7 +235,7 @@ void setup_env (struct passwd *info)
 	if (NULL == cp) {
 		/* not specified, use a minimal default */
 		addenv ((info->pw_uid == 0) ? "PATH=/sbin:/bin:/usr/sbin:/usr/bin" : "PATH=/bin:/usr/bin", NULL);
-	} else if (strchr (cp, '=')) {
+	} else if (strchr(cp, '=')) {
 		/* specified as name=value (PATH=...) */
 		addenv (cp, NULL);
 	} else {

lib/tcbfuncs.c

@@ -189,7 +189,7 @@ static shadowtcb_status mkdir_leading (const char *name, uid_t uid)
 		         shadow_progname, TCB_DIR, strerror (errno));
 		goto out_free_path;
 	}
-	while ((ind = strchr (ptr, '/'))) {
+	while (NULL != (ind = strchr(ptr, '/'))) {
 		stpcpy(ind, "");
 		dir = aprintf(TCB_DIR "/%s", path);
 		if (dir == NULL) {

lib/utmp.c

@@ -410,12 +410,12 @@ active_sessions_count(const char *name, unsigned long limit)
 		if (USER_PROCESS != ut->ut_type) {
 			continue;
 		}
-		if ('\0' == ut->ut_user[0]) {
+		if (strncmp(ut->ut_user, "", countof(ut->ut_user)) == 0)
 			continue;
-		}
-		if (strncmp (name, ut->ut_user, sizeof (ut->ut_user)) != 0) {
+
+		if (strncmp(ut->ut_user, name, countof(ut->ut_user)) != 0)
 			continue;
-		}
+
 		count++;
 		if (count > limit) {
 			break;

src/chfn.c

@@ -15,6 +15,7 @@
 #include <pwd.h>
 #include <signal.h>
 #include <stdio.h>
+#include <string.h>
 #include <sys/types.h>
 #include <getopt.h>
 
@@ -160,9 +161,8 @@ static bool may_change_field (int field)
 		cp = "frwh";
 	}
 
-	if (strchr (cp, field) != NULL) {
+	if (strchr(cp, field))
 		return true;
-	}
 
 	return false;
 }

src/chpasswd.c

@@ -17,6 +17,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #ifdef USE_PAM
 #include "pam_defs.h"
@@ -509,10 +510,8 @@ int main (int argc, char **argv)
 			if (feof (stdin) == 0) {
 				// Drop all remaining characters on this line.
 				while (fgets (buf, sizeof buf, stdin) != NULL) {
-					cp = strchr (buf, '\n');
-					if (cp != NULL) {
+					if (strchr(buf, '\n'))
 						break;
-					}
 				}
 
 				fprintf (stderr,

src/login_nopam.c

@@ -315,9 +315,8 @@ static bool from_match (char *tok, const char *string)
 			return true;
 		}
 	} else if (strcaseeq(tok, "LOCAL")) {	/* LOCAL: no dots */
-		if (strchr (string, '.') == NULL) {
+		if (!strchr(string, '.'))
 			return true;
-		}
 	} else if (   (!streq(tok, "") && tok[strlen(tok) - 1] == '.') /* network */
 		   && strprefix(resolve_hostname(string), tok)) {
 		return true;

src/logoutd.c

@@ -13,6 +13,7 @@
 #include <fcntl.h>
 #include <signal.h>
 #include <stdio.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <utmpx.h>
@@ -178,9 +179,9 @@ main(int argc, char **argv)
 			if (ut->ut_type != USER_PROCESS) {
 				continue;
 			}
-			if (ut->ut_user[0] == '\0') {
+			if (strncmp(ut->ut_user, "", countof(ut->ut_user)) == 0)
 				continue;
-			}
+
 			if (check_login (ut)) {
 				continue;
 			}

src/su.c

@@ -951,7 +951,7 @@ static void set_environment (struct passwd *pw)
 	cp = getdef_str ((pw->pw_uid == 0) ? "ENV_SUPATH" : "ENV_PATH");
 	if (NULL == cp) {
 		addenv ((pw->pw_uid == 0) ? "PATH=/sbin:/bin:/usr/sbin:/usr/bin" : "PATH=/bin:/usr/bin", NULL);
-	} else if (strchr (cp, '=') != NULL) {
+	} else if (strchr(cp, '=')) {
 		addenv (cp, NULL);
 	} else {
 		addenv ("PATH", cp);