update from main archive 961214cvs/libc-961215

Sun Dec 15 01:53:20 1996  Ulrich Drepper  <drepper@cygnus.com>

	* Makefile (subdirs): Change crypt to md5-crypt.
	* crypt/Makefile, crypt/md5-crypt.c, crypt/md5.c, crypt/md5.h,
	crypt/md5c-test.c, crypt/md5test.c: Move to new directory
	md5-crypt.
	* sysdeps/unix/sysv/linux/configure.in: Refer to linuxthreads and
	crypt instead of LinuxThreads and des-crypt.

	* Makefile (subdirs): Add nss back.
	* sysdeps/unix/inet/Subdirs: Move nis to end of file to fulfill
	dependencies.

	* libio/iofclose.c: Implement fclose(NULL) as closing all streams.
	* stdio-common/Makefile (routines): Add fcloseall.
	* stdio-common/fcloseall.c: New file.
	* sysdeps/generic/abort.c: Make implementation POSIX.1 compatible.

	* sysdeps/mach/libc-lock.h: Add definition of __libc_lock_trylock.
	* sysdeps/stub/libc-lock.h: Define __libc_lock_trylock to always
	return 0.

	* stdio-common/printf.h: Define MIN and MAX only if not already
	defined.

	* stdio-common/vfprintf.c: Set errno to EBADF if stream does not
	allow writing.  Required by POSIX.1.

	* libio/libioP.h (CHECK_FILE): Use MAYBE_SET_EINVAL instead of
	assignment.

	* interp.c: Update copyright.
	* libio/clearerr.c: Likewise.
	* libio/ioseekoff.c: Likewise.
	* libio/ioseekpos.c: Likewise.
	* stdio/fclose.c: Likewise.
	* stdio/fflus.c: Likewise.

	* libio/libio.h [!_IO_MTSAFE_IO]: Define _IO_cleanup_region_start
	and _IO_cleanup_region_end as empty.
	* libio/fgetc.c: Use _IO_cleanup_region_start and
	_IO_cleanup_region_end instead of __libc_cleanup_region_start and
	__libc_cleanup_region_end.
	* libio/fputc.c: Likewise.
	* libio/freopen.c: Likewise.
	* libio/fseek.c: Likewise.
	* libio/getc.c: Likewise.
	* libio/getchar.c: Likewise.
	* libio/iofclose.c: Likewise.
	* libio/iofflush.c: Likewise.
	* libio/iofgetpos.c: Likewise.
	* libio/iofgets.c: Likewise.
	* libio/iofputs.c: Likewise.
	* libio/iofread.c: Likewise.
	* libio/iofsetpos.c: Likewise.
	* libio/ioftell.c: Likewise.
	* libio/iofwrite.c: Likewise.
	* libio/iogetdelim.c: Likewise.
	* libio/iogets.c: Likewise.
	* libio/ioputs.c: Likewise.
	* libio/iosetbuffer.c: Likewise.
	* libio/iosetvbuf.c: Likewise.
	* libio/ioungetc.c: Likewise.

	* libio/iovspintf.c: Use cleanup handler to make sure no dangling
	locks can stay over.
	* libio/iovsscanf.c: Likewise.

	* libio/genops.c: Use _IO_lock_init_recursive and _IO_lock_fini
	instead of __libc_lock_init_recursive and __libc_lock_fini.

	* libio/filedoalloc.c: Only use __isatty when compiling GNU libc.
	Otherwise use isatty.
	* libio/fileops.c: Likewise for __open and open.

	* login/utmp_file.c (getutent_r_file): Use fcntl instead of
	flock.

	* nis/ypclnt.h: Add more casts to prevent warnings.

	* nss/Makefile (services): Remove dns.
	(libnss_dns, libnss_dns-inhibit-o): Remove definition.
	($(objpfx)libnss_dns.so): Removed.
	* nss/nss_dns/dns-host.c, nss/nss_dns/dns-network.c: Moved to...
	* resolv/nss_dns: ...here.
	* resolv/Makefile (extra-libs): Add libnss_dns.
	(libnss_dns-routines, libnss_dns-inhibit-o): Define as in
	nss/Makefile.

	* nss/XXX-lookup.c: Call __nss_database_lookup with new argument
	specifying alternate name for entry in /etc/nsswitch.conf
	* nss/nsswitch.c: If no entry with primary name is found in
	/etc/nsswitch.conf try alternate name if given.
	* nss/nsswitch.h: Add new parameter in prototype for
	__nss_database_lookup.
	* nss/spwd-lookup.c: Provide alternative entry name to look for.
	This makes our NSS compatible with Solaris' nsswitch.conf files.

	* string/tst-strlen.c: Change all counting variables to type size_t
	to prevent warnings.

	* sysdeps/posix/fpathconf.c: Update copyright.
	* sysdeps/posix/pathconf.c: Don't call fpathconf to do the work.
	Opening the file at this path may fail if it is a FIFO or pipe.

	These changes make the time implementation POSIX.1 compliant.
	* time/localtime.c (__localtime_r): Always call __tzset not only
	if __tzset_run is zero.
	* time/strftime.c: Add definition of memset_space to help to
	reduce for systems which have memset.
	(strftime): Don't use tm_zone member of argument for zone name.
	Instead always use tzname[].
	Call tzset() as required by POSIX.1 before any action.
	* time/tzset.c (tzset): Set tzname[] as required by POSIX.1.
	Remove global variable __tzset_run.  __tzset is now called always
	when a dependent function is used.
	(__tzset): Caching happens based on the contents of the
	environment variable TZ.

Fri Dec 13 01:06:52 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/unix/sysv/linux/paths.h: Add _PATH_KLOG.

Thu Dec 12 09:16:35 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* rellns-sh: Correctly handle a relative source file name.

Wed Dec 11 19:18:40 1996  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* login/utmp_file.c (setutent_file): Seek back to beginning of the
	file if resetting.

Thu Dec 12 16:39:12 1996  Thomas Bushnell, n/BSG  <thomas@gnu.ai.mit.edu>

	* hurd/hurdinit.c (map0): Delete function.  Don't do this on
	_hurd_preinit_hook.
	* hurd/hurdstartup.c (_hurd_startup): Map page zero redzone here.

1 files changed, 17 insertions, 2 deletions

diff --git a/login/utmp_file.c b/login/utmp_file.c
index 2bb6c92..c728d9a 100644
--- a/login/utmp_file.c
+++ b/login/utmp_file.c
@@ -92,6 +92,8 @@ setutent_file (int reset)
     }
   else if (reset)
     {
+      lseek (file_fd, 0, SEEK_SET);
+
       /* Remember we are at beginning of file.  */
       file_offset = 0;
 
@@ -117,6 +119,7 @@ static int
 getutent_r_file (struct utmp *buffer, struct utmp **result)
 {
   int nbytes;
+  struct flock fl;			/* Information struct for locking.  */
 
   /* Open utmp file if not already done.  */
   if (file_fd == INT_MIN)
@@ -129,10 +132,22 @@ getutent_r_file (struct utmp *buffer, struct utmp **result)
       return -1;
     }
 
+  /* XXX The following is not perfect.  Instead of locking the file itself
+     Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl> suggests to
+     use an extra locking file.  */
+
+  /* Try to get the lock.  */
+  memset (&fl, '\0', sizeof (struct flock));
+  fl.l_type = F_WRLCK;
+  fl.l_whence = SEEK_SET;
+  result = fcntl (file_fd, F_SETLKW, &fl);
+
   /* Read the next entry.  */
-  flock (file_fd, LOCK_SH);
   nbytes = read (file_fd, &last_entry, sizeof (struct utmp));
-  flock (file_fd, LOCK_UN);
+
+  /* And unlock the file.  */
+  fl.l_type = F_UNLCK;
+  result = fcntl (file_fd, F_SETLKW, &fl);
 
   if (nbytes != sizeof (struct utmp))
     {