Added function and man page for ftok(3), used in conjunction with

the so-called "System V IPC".

Submitted by:	jbeukema@HK.Super.Net (John Beukema)
Obtained from:  Th. Lockert <tholo@sigmasoft.com>, via NetBSD

3 files changed, 143 insertions, 1 deletions

diff --git a/lib/libcompat/Makefile b/lib/libcompat/Makefile
index c06a385..8c0089e 100644
--- a/lib/libcompat/Makefile
+++ b/lib/libcompat/Makefile
@@ -8,7 +8,8 @@ NOPIC=
 .PATH:	${.CURDIR}/4.1/${MACHINE} ${.CURDIR}/4.1 \
 	${.CURDIR}/4.3/${MACHINE} ${.CURDIR}/4.3 \
 	${.CURDIR}/4.4/${MACHINE} ${.CURDIR}/4.4 \
-	${.CURDIR}/regexp
+	${.CURDIR}/regexp \
+	${.CURDIR}/SysV
 
 # compat 4.1 sources
 # XXX MISSING:	tell.c vlimit.c vtimes.c
@@ -62,4 +63,10 @@ MAN3+=	regexp/regexp.3
 MLINKS+=regexp.3 regcomp.3 regexp.3 regexec.3 regexp.3 regsub.3 \
 	regexp.3 regerror.3
 
+# SysV compat sources
+SRCS+=	ftok.c
+
+MAN3+=	SysV/ftok.3
+
+
 .include <bsd.lib.mk>
diff --git a/lib/libcompat/SysV/ftok.3 b/lib/libcompat/SysV/ftok.3
new file mode 100644
index 0000000..9b25bf2
--- /dev/null
+++ b/lib/libcompat/SysV/ftok.3
@@ -0,0 +1,88 @@
+.\" Copyright (c) 1994 SigmaSoft, Th. Lockert <tholo@sigmasoft.com>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. The name of the author may not be used to endorse or promote products
+.\"    derived from this software without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\"	$Id: ftok.3,v 1.1 1994/06/26 16:24:57 jtc Exp $
+.Dd June 24, 1994
+.Os
+.Dt ftok 3
+.Sh NAME
+.Nm ftok
+.Nd create IPC indentifier from path name
+.Sh SYNOPSIS
+.Fd #include <sys/types.h>
+.Fd #include <sys/ipc.h>
+.Ft key_t
+.Fn ftok "const char *path" "char id" ;
+.Sh DESCRIPTION
+.Bf -symbolic
+This function is available from the compatibility library, libcompat.
+.Ef
+The
+.Fn ftok
+function attempts to create a unique key suitable for use with the
+.Xr msgget 2 ,
+.Xr semget 2
+and
+.Xr shmget 2
+functions given the
+.Fa path
+of an existing file and a user-selectable
+.Fa id .
+.Pp
+The specified
+.Fa path
+must specify an existing file that is accessible to the calling process
+or the call will fail.  Also, note that links to files will return the
+same key, given the same
+.Fa id .
+.Sh RETURN VALUES
+The
+.Fn ftok
+function will return -1 if
+.Fa path
+does not exist or if it cannot be accessed by the calling process.
+.Sh SEE ALSO
+.Xr msgget 2 ,
+.Xr semget 2 ,
+.Xr shmget 2
+.Sh HISTORY
+The
+.Fn ftok
+function originate with System V and is typically used by programs
+that use the System V IPC routines.
+.Sh AUTHOR
+.Bl -tag
+Thorsten Lockert <tholo@sigmasoft.com>
+.El
+.Sh BUGS
+The returned key is computed based on the device and inode of the
+specified
+.Fa path
+in combination with the given
+.Fa id .
+Thus is is quite possible for the routine to return duplicate keys
+given that those fields are not 8- and 16-bit quantities like they
+were on System V based systems where this library routine's ancestor
+were originally created.
diff --git a/lib/libcompat/SysV/ftok.c b/lib/libcompat/SysV/ftok.c
new file mode 100644
index 0000000..8861509
--- /dev/null
+++ b/lib/libcompat/SysV/ftok.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 1994 SigmaSoft, Th. Lockert <tholo@sigmasoft.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char *rcsid = "$Id: ftok.c,v 1.2 1994/06/26 16:27:34 jtc Exp $";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ipc.h>
+
+key_t
+ftok(path, id)
+	const char *path;
+	char id;
+{
+	struct stat st;
+
+	if (stat(path, &st) < 0)
+		return (key_t)-1;
+
+	return (key_t) (id << 24 | (st.st_dev & 0xff) << 16 | (st.st_ino & 0xffff));
+}