Some cleanups so utmp/wtmp behaves. Fix potential use of

uninitialized memory.  Prepare to reentrantify the utmp
stuff.
 -Erik

1 files changed, 44 insertions, 58 deletions

diff --git a/libutil/logwtmp.c b/libutil/logwtmp.c
index 6a8f6bd14..35d809d96 100644
--- a/libutil/logwtmp.c
+++ b/libutil/logwtmp.c
@@ -1,73 +1,59 @@
-/* Copyright (C) 1996, 1997 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Library General Public License as
-   published by the Free Software Foundation; either version 2 of the
-   License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Library General Public License for more details.
-
-   You should have received a copy of the GNU Library General Public
-   License along with the GNU C Library; see the file COPYING.LIB.  If not,
-   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-   Boston, MA 02111-1307, USA.  */
+/* wtmp support rubbish (i.e. complete crap)
+ *
+ * Written by Erik Andersen <andersee@debian.org> 
+ *
+ * This library is free software; you can redistribute it and/or 
+ * modify it under the terms of the GNU Library General Public License as 
+ * published by the Free Software Foundation; either version 2 of the 
+ * License, or (at your option) any later version.  
+ *
+ * This library is distributed in the hope that it will be useful, 
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU 
+ * Library General Public License for more details.  
+ *
+ * You should have received a copy of the GNU Library General Public 
+ * License along with this library; see the file COPYING.LIB.  If not, 
+ * write to the Free Software Foundation, Inc., 675 Mass Ave, 
+ * Cambridge, MA 02139, USA.  */
 
 #include <string.h>
 #include <sys/time.h>
 #include <time.h>
 #include <unistd.h>
-#include <fcntl.h>
 #include <utmp.h>
+#include <fcntl.h>
+#include <sys/file.h>
 
 
 void logwtmp (const char *line, const char *name, const char *host)
 {
-  struct utmp ut;
-  struct flock lock;
-  int ut_fd;
-
-
-  /* Set information in new entry.  */
-  memset (&ut, 0, sizeof (ut));
-#if _HAVE_UT_PID - 0
-  ut.ut_pid = getpid ();
-#endif
-#if _HAVE_UT_TYPE - 0
-  ut.ut_type = name[0] ? USER_PROCESS : DEAD_PROCESS;
-#endif
-  strncpy (ut.ut_line, line, sizeof ut.ut_line);
-  strncpy (ut.ut_name, name, sizeof ut.ut_name);
-#if _HAVE_UT_HOST - 0
-  strncpy (ut.ut_host, host, sizeof ut.ut_host);
-#endif
+    struct utmp lutmp;
+    memset (&(lutmp), 0, sizeof (struct utmp));
 
-#if _HAVE_UT_TV - 0
-  gettimeofday (&ut.ut_tv, NULL);
-#else
-  time (&ut.ut_time);
-#endif
+    lutmp.ut_type = (name && *name)? USER_PROCESS : DEAD_PROCESS;
+    lutmp.ut_pid = getpid();
+    strncpy(lutmp.ut_line, line, sizeof(lutmp.ut_line)-1);
+    strncpy(lutmp.ut_name, name, sizeof(lutmp.ut_name)-1);
+    strncpy(lutmp.ut_host, host, sizeof(lutmp.ut_host)-1);
+    gettimeofday(&(lutmp.ut_tv), NULL);
 
-/*  updwtmp (_PATH_WTMP, &ut); */
-/* from tinylogin */
+    updwtmp(_PATH_WTMP, &(lutmp));
+}
 
-	if ((ut_fd = open(_PATH_WTMP, O_APPEND | O_WRONLY)) >= 0) {
-		/* Lock the utmp file before updating */
-		lock.l_type = F_WRLCK;
-		lock.l_whence = SEEK_SET;
-		lock.l_start = 0;
-		lock.l_len = 0;
-		if (fcntl(ut_fd, F_SETLK, &lock) >= 0) {
-			write(ut_fd, (void *) &ut, sizeof(ut));
-			/* Now unlock the utmp file */
-			lock.l_type = F_UNLCK;
-		}
-		close(ut_fd);
+#if 0
+/* This is enabled in uClibc/libc/misc/utmp/wtent.c */
+extern void updwtmp(const char *wtmp_file, const struct utmp *lutmp)
+{
+    int fd;
+
+    fd = open(wtmp_file, O_APPEND | O_WRONLY, 0);
+    if (fd >= 0) {
+	if (lockf(fd, F_LOCK, 0)==0) {
+	    write(fd, (const char *) lutmp, sizeof(struct utmp));
+	    lockf(fd, F_ULOCK, 0);
+	    close(fd);
 	}
-
-
+    }
 }
+#endif