need #defines to make flock use lockf

Mark Davies mark at comp.vuw.ac.nz
Wed Oct 3 12:34:38 AEST 1990


In article <1990Oct2.213652.20025 at ux1.cso.uiuc.edu> paul at uxc.cso.uiuc.edu (Paul Pomes - UofIllinois CSO) writes:
>I have a program that makes use of flock() scattered around several files.
>Rather than cluttering the code with #ifdefs for both flock() and lockf(),
>I'd like to redefine the flock calls in a common include file to use lockf
>instead when #ifndef BSD is true.  Has anyone already created such a beast?

This is the flock() emulation we use for sendmail and a few other programs
on our hpux boxes and I think its now also been run on a SysV box.

cheers
mark

#! /bin/sh
# This is a shell archive.  Remove anything before this line, then unpack
# it by saving it into a file and typing "sh file".  To overwrite existing
# files, type "sh file -c".  You can also feed this as standard input via
# unshar, or by typing "sh <file", e.g..  If this archive is complete, you
# will see the following message at the end:
#		"End of shell archive."
# Contents:  flock.c flock.h
# Wrapped by mark at the-taj.comp.vuw.ac.nz on Wed Oct  3 14:30:18 1990
PATH=/bin:/usr/bin:/usr/ucb ; export PATH
if test -f 'flock.c' -a "${1}" != "-c" ; then 
  echo shar: Will not clobber existing file \"'flock.c'\"
else
echo shar: Extracting \"'flock.c'\" \(2049 characters\)
sed "s/^X//" >'flock.c' <<'END_OF_FILE'
X/*
X * Copyright (c) 1989 Mark Davies
X * Copyright (c) 1990 Andy Linton
X * Copyright (c) 1990 Victoria University of Wellington.
X * All rights reserved.
X *
X * Redistribution and use in source and binary forms are permitted provided
X * that: (1) source distributions retain this entire copyright notice and
X * comment, and (2) distributions including binaries display the following
X * acknowledgement:  ``This product includes software developed by the
X * Victoria University of Wellington, New Zealand and its contributors''
X * in the documentation or other materials provided with the distribution
X * and in all advertising materials mentioning features or use of this
X * software.
X * Neither the name of the University nor the names of its contributors may
X * be used to endorse or promote products derived from this software without
X * specific prior written permission.
X * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
X * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
X * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
X */
X
X#include <unistd.h>
X#include <sys/types.h>
X#include <errno.h>
X#include <fcntl.h>
X#include "flock.h"               /* defines normally in <sys/file.h> */
X
X
X#if defined(F_SETLK) && defined(F_SETLKW)
X
Xflock(fd, operation)
Xint fd, operation;
X{
X	int op, ret;
X	struct flock arg;
X	extern int errno;
X
X	op = (LOCK_NB & operation) ? F_SETLK : F_SETLKW;
X	
X	arg.l_type = (LOCK_EX & operation) ? F_WRLCK :
X		(LOCK_SH & operation) ? F_RDLCK : F_UNLCK;
X	arg.l_whence = 0;
X	arg.l_start = 0;
X	arg.l_len = 0;
X	arg.l_pid = 0;
X	
X	if ((ret = fcntl(fd, op, &arg)) == -1) {
X		if (errno == EACCES || errno == EAGAIN)
X			errno = EWOULDBLOCK;
X	}
X	return (ret);
X}
X
X#else
X
Xflock(fd, operation)
Xint fd, operation;
X{
X	int op, ret;
X	extern int errno;
X
X	op = (LOCK_UN & operation) ? F_ULOCK :
X	  (LOCK_NB & operation) ? F_TLOCK : F_LOCK;
X
X	if ((ret = lockf(fd, op, 0)) == -1) {
X		if (errno == EACCES || errno == EAGAIN)
X			errno = EWOULDBLOCK;
X	}
X
X	return (ret);
X}
X
X#endif /* F_SETLK && F_SETLKW */
X
END_OF_FILE
if test 2049 -ne `wc -c <'flock.c'`; then
    echo shar: \"'flock.c'\" unpacked with wrong size!
fi
# end of 'flock.c'
fi
if test -f 'flock.h' -a "${1}" != "-c" ; then 
  echo shar: Will not clobber existing file \"'flock.h'\"
else
echo shar: Extracting \"'flock.h'\" \(413 characters\)
sed "s/^X//" >'flock.h' <<'END_OF_FILE'
X/* These definitions are in <sys/file.h> on BSD 4.3 */
X
X#if defined(F_SETLK) && defined(F_SETLKW)
X# define FCNTL_FLOCK
X#else
X# define LOCKF_FLOCK
X#endif /* F_SETLK && F_SETLKW */
X/*
X * Flock call.
X */
X#define LOCK_SH         1       /* shared lock */
X#define LOCK_EX         2       /* exclusive lock */
X#define LOCK_NB         4       /* don't block when locking */
X#define LOCK_UN         8       /* unlock */
END_OF_FILE
if test 413 -ne `wc -c <'flock.h'`; then
    echo shar: \"'flock.h'\" unpacked with wrong size!
fi
chmod +x 'flock.h'
# end of 'flock.h'
fi
echo shar: End of shell archive.
exit 0



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