Don't test for NULL before calling free(3)

free(3) accepts NULL, since the oldest ISO C.  I guess the
paranoid code was taking care of prehistoric implementations of
free(3).  I've never known of an implementation that doesn't
conform to this, so let's simplify this.

Remove xfree(3), which was effectively an equivalent of free(3).

Signed-off-by: Alejandro Colomar <alx@kernel.org>

src/gpasswd.c

@@ -1186,17 +1186,11 @@ int main (int argc, char **argv)
 
 #ifdef SHADOWGRP
 	if (is_shadowgrp) {
-		if (sgent.sg_adm) {
-			xfree(sgent.sg_adm);
-		}
-		if (sgent.sg_mem) {
-			xfree(sgent.sg_mem);
-		}
+		free(sgent.sg_adm);
+		free(sgent.sg_mem);
 	}
 #endif
-	if (grent.gr_mem) {
-		xfree(grent.gr_mem);
-	}
+	free(grent.gr_mem);
 	exit (E_SUCCESS);
 }
 

src/login.c

@@ -419,9 +419,7 @@ static void get_pam_user (char **ptr_pam_user)
 	retcode = pam_get_item (pamh, PAM_USER, (const void **)&ptr_user);
 	PAM_FAIL_CHECK;
 
-	if (NULL != *ptr_pam_user) {
-		free (*ptr_pam_user);
-	}
+	free (*ptr_pam_user);
 	if (NULL != ptr_user) {
 		*ptr_pam_user = xstrdup ((const char *)ptr_user);
 	} else {
@@ -872,9 +870,7 @@ int main (int argc, char **argv)
 	 * PAM APIs.
 	 */
 	get_pam_user (&pam_user);
-	if (NULL != username) {
-		free (username);
-	}
+	free (username);
 	username = xstrdup (pam_user);
 	failent_user = get_failent_user (username);
 

src/newusers.c

@@ -285,8 +285,7 @@ static int add_group (const char *name, const char *gid, gid_t *ngid, uid_t uid)
 		fprintf (stderr,
 		         _("%s: invalid group name '%s'\n"),
 		         Prog, grent.gr_name);
-		if (grent.gr_name)
-			free (grent.gr_name);
+		free (grent.gr_name);
 		return -1;
 	}