login: fix "ignoring return value" errors

login.c:542:8: warning: ignoring return value of ‘fchown’, declared
with attribute warn_unused_result
login.c:1013:11: warning: ignoring return value of ‘fchown’, declared
with attribute warn_unused_result
login.c: In function ‘dolastlog’:
login.c:1452:7: warning: ignoring return value of ‘write’, declared
with attribute warn_unused_result
login.c: In function ‘motd’:
login.c:1391:7: warning: ignoring return value of ‘write’, declared
with attribute warn_unused_result

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/login.c b/login-utils/login.c
index 5ece59b2a936278258a9796944d7a293029b09f2..ad2932d0b14fdc7a4c87ecba901ab94901370637 100644 (file)
--- a/login-utils/login.c
+++ b/login-utils/login.c
@@ -539,7 +539,10 @@ main(int argc, char **argv)
        ttt.c_cflag &= ~HUPCL;
 
        /* These can fail, e.g. with ttyn on a read-only filesystem */
-       fchown(0, 0, 0);
+       if (fchown(0, 0, 0)) {
+               ; /* glibc warn_unused_result */
+       }
+
        fchmod(0, TTY_MODE);
 
        /* Kill processes left on this tty */
@@ -1010,16 +1013,22 @@ Michael Riepe <michael@stud.uni-hannover.de>
     logaudit(tty_name, username, hostname, pwd, 1);
     dolastlog(quietlog);
 
-    fchown(0, pwd->pw_uid,
-         (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
+    if (fchown(0, pwd->pw_uid,
+         (gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid))
+        warn(_("change terminal owner failed"));
+
     fchmod(0, TTY_MODE);
 
 #ifdef LOGIN_CHOWN_VCS
     /* if tty is one of the VC's then change owner and mode of the
        special /dev/vcs devices as well */
     if (consoletty(0)) {
-       chown(vcsn, pwd->pw_uid, (gr ? gr->gr_gid : pwd->pw_gid));
-       chown(vcsan, pwd->pw_uid, (gr ? gr->gr_gid : pwd->pw_gid));
+
+       if (chown(vcsn, pwd->pw_uid, (gr ? gr->gr_gid : pwd->pw_gid)))
+           warn(_("change terminal owner failed"));
+       if (chown(vcsan, pwd->pw_uid, (gr ? gr->gr_gid : pwd->pw_gid)))
+           warn(_("change terminal owner failed"));
+
        chmod(vcsn, TTY_MODE);
        chmod(vcsan, TTY_MODE);
     }
@@ -1387,8 +1396,11 @@ motd(void) {
       return;
     oldint = signal(SIGINT, sigint);
     if (setjmp(motdinterrupt) == 0)
-      while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
-       write(fileno(stdout), tbuf, nchars);
+      while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) {
+       if (write(fileno(stdout), tbuf, nchars)) {
+               ;       /* glibc warn_unused_result */
+       }
+      }
     signal(SIGINT, oldint);
     close(fd);
 }
@@ -1405,8 +1417,11 @@ checknologin(void) {
     char tbuf[8192];
 
     if ((fd = open(_PATH_NOLOGIN, O_RDONLY, 0)) >= 0) {
-       while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
-         write(fileno(stdout), tbuf, nchars);
+       while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0) {
+         if (write(fileno(stdout), tbuf, nchars)) {
+               ;       /* glibc warn_unused_result */
+         }
+       }
        close(fd);
        sleepexit(EXIT_SUCCESS);
     }
@@ -1449,7 +1464,8 @@ dolastlog(int quiet) {
        if (hostname)
            xstrncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
 
-       write(fd, (char *)&ll, sizeof(ll));
+       if (write(fd, (char *)&ll, sizeof(ll)) < 0)
+           warn(_("write lastlog failed"));
        close(fd);
     }
 }