#!/bin/sh
# This is a shar archive.
# The rest of this file is a shell script which will extract:
#
# 8_11.h 8_11a.h makefile rc.h rctst.c tst.cmp tst.data tst.save tst2.cmp
#
# To extract the files from this shell archive file simply
# create a directory for this file, move the archive file
# to it and enter the command
#
#	sh filename
# 
# The files will be extracted automatically.
# Note: Do not use csh.
#
# Archive created: Mon Jul 30 23:12:05 EDT 1990
#
echo x - 8_11.h
sed 's/^X//' > 8_11.h << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
// Exercise 8.11
// Generic random access to objects kept within a file.
// The user would use the generic class randomOBJ
// for a user type TYPE by the following steps:
//
// declare(randomOBJ,TYPE)
// implement(randomOBJ,TYPE)
// ...
// randomOBJ(TYPE) x("filename",
//		     read-err-func, write-err-func);
// randomOBJ(TYPE) y("filename");

#ifndef RANDACCESS_H
#define RANDACCESS_H
#include <stdio.h>
#include <generic.h>

#include "8_11a.h" /* EXPAND */

/*
   An extended FILE which keeps track of its
   current location within the file. This class
   has no type-specific implementation and can
   be used across all instantiations of randomOBJ.
*/

class eFILE
{
    long fileoffset;
    FILE *fp;
    eFILE() { };

public:
    friend eFILE *efopen(char *file);
    friend void efclose(eFILE *efp);
    friend int egetobj(eFILE *efp, long offset,
	void *obj, unsigned szobj);
    friend int eputobj(eFILE *efp, long offset,
	void *obj, unsigned szobj);
};

#define randomOBJdeclare(type)				\
    class randomOBJ(type);				\
							\
    class OBJrandomloc(type)				\
    {							\
	randomOBJ(type) *rOBJ;				\
	long thisoffset;				\
							\
    public:						\
	OBJrandomloc(type)(randomOBJ(type) *robj,	\
			   long offset)			\
	{						\
	    rOBJ = robj;				\
	    thisoffset = offset;			\
	}						\
							\
	operator type();				\
							\
	OBJrandomloc(type) operator=(type newobj);	\
	OBJrandomloc(type) operator=(			\
	    OBJrandomloc(type) r);			\
    };							\
							\
    class randomOBJ(type)				\
    {							\
	eFILE *rfp;					\
	void (*rdrfnc)(type *);				\
	void (*wtrfnc)(type *);				\
	friend OBJrandomloc(type);			\
	OBJrandomloc(type) operator=(type newobj);	\
							\
    public:						\
	randomOBJ(type)(char *filename,			\
	    void (*rfnc)(type *) = 0,			\
	    void (*wfnc)(type *) = 0)			\
	{						\
	    rfp = efopen(filename);			\
	    rdrfnc = rfnc;				\
	    wtrfnc = wfnc;				\
	}						\
							\
	~randomOBJ(type)()				\
	{						\
	    efclose(rfp);				\
	}						\
							\
	int openedokay()				\
	{						\
	    return rfp != 0;				\
	}						\
							\
	OBJrandomloc(type) operator[](long offset)	\
	{						\
	    OBJrandomloc(type) ret(this, offset);	\
	    return ret;					\
	}						\
    };

#define randomOBJimplement(type)			\
    OBJrandomloc(type)::operator type()			\
    {							\
	type x;						\
	if (!egetobj(rOBJ->rfp, thisoffset, &x,		\
		     sizeof x))				\
	    if (rOBJ->rdrfnc)				\
		(*rOBJ->rdrfnc)(&x);			\
	return x;					\
    }							\
							\
    OBJrandomloc(type) OBJrandomloc(type)::operator=(	\
	type newobj)					\
    {							\
	if (!eputobj(rOBJ->rfp, thisoffset,		\
		     &newobj, sizeof newobj))		\
	    if (rOBJ->wtrfnc)				\
		(*rOBJ->wtrfnc)(&newobj);		\
	return *this;					\
    }							\
							\
    OBJrandomloc(type) OBJrandomloc(type)::operator=(	\
				 OBJrandomloc(type) r)	\
    {							\
	return (*this = (type) r);			\
    }
#endif /* RANDACCESS_H */
!EOF!
ls -l 8_11.h
echo x - 8_11a.h
sed 's/^X//' > 8_11a.h << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#define randomOBJ(type) name3(type,random,OBJ)
#define OBJrandomloc(type) name3(type,OBJ,randomloc)

!EOF!
ls -l 8_11a.h
echo x - makefile
sed 's/^X//' > makefile << '!EOF!'
CC= CC -I. -I../../CC
CFLAGS= +i -g

all: rctst

rctst: rctst.c rc.h 8_11a.h ../8.10dir/pr.c ../8.9dir/8_9a2.c \
	../8.9dir/8_9a3.c ../8.10dir/8_10a4.c ../8.10dir/8_10a5.c
	$(CC) $(CFLAGS) rctst.c -o rctst

CMP= tst.cmp tst2.cmp
OUT= tst.out

tst.out: rctst tst.save
	cp tst.save tst.data
	rctst > tst.out

test: $(CMP) $(OUT)
	cmp tst.out tst.cmp
	cmp tst.data tst2.cmp
	@echo test done
!EOF!
ls -l makefile
echo x - rc.h
sed 's/^X//' > rc.h << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
// Exercise 8.11
// Generic random access to objects kept within a file.
// The user would use the generic class randomOBJ
// for a user type TYPE by the following steps:
//
// declare(randomOBJ,TYPE)
// implement(randomOBJ,TYPE)
// ...
// randomOBJ(TYPE) x("filename",
//		     read-err-func, write-err-func);
// randomOBJ(TYPE) y("filename");

#ifndef RANDACCESS_H
#define RANDACCESS_H
#include <stdio.h>
#include <generic.h>

#include "8_11a.h" /* EXPAND */

/*
   An extended FILE which keeps track of its
   current location within the file. This class
   has no type-specific implementation and can
   be used across all instantiations of randomOBJ.
*/

class eFILE
{
    long fileoffset;
    FILE *fp;
    eFILE() { };

public:
    friend eFILE *efopen(char *file);
    friend void efclose(eFILE *efp);
    friend int egetobj(eFILE *efp, long offset,
	void *obj, unsigned szobj);
    friend int eputobj(eFILE *efp, long offset,
	void *obj, unsigned szobj);
};

#define randomOBJdeclare(type)				\
    class randomOBJ(type);				\
							\
    class OBJrandomloc(type)				\
    {							\
	randomOBJ(type) *rOBJ;				\
	long thisoffset;				\
							\
    public:						\
	OBJrandomloc(type)(randomOBJ(type) *robj,	\
			   long offset)			\
	{						\
	    rOBJ = robj;				\
	    thisoffset = offset;			\
	}						\
							\
	operator type();				\
							\
	OBJrandomloc(type) operator=(type newobj);	\
	OBJrandomloc(type) operator=(			\
	    OBJrandomloc(type) r);			\
    };							\
							\
    class randomOBJ(type)				\
    {							\
	eFILE *rfp;					\
	void (*rdrfnc)(type *);				\
	void (*wtrfnc)(type *);				\
	friend OBJrandomloc(type);			\
	OBJrandomloc(type) operator=(type newobj);	\
							\
    public:						\
	randomOBJ(type)(char *filename,			\
	    void (*rfnc)(type *) = 0,			\
	    void (*wfnc)(type *) = 0)			\
	{						\
	    rfp = efopen(filename);			\
	    rdrfnc = rfnc;				\
	    wtrfnc = wfnc;				\
	}						\
							\
	~randomOBJ(type)()				\
	{						\
	    efclose(rfp);				\
	}						\
							\
	int openedokay()				\
	{						\
	    return rfp != 0;				\
	}						\
							\
	OBJrandomloc(type) operator[](long offset)	\
	{						\
	    OBJrandomloc(type) ret(this, offset);	\
	    return ret;					\
	}						\
    };

#define randomOBJimplement(type)			\
    OBJrandomloc(type)::operator type()			\
    {							\
	type x;						\
	if (!egetobj(rOBJ->rfp, thisoffset, &x,		\
		     sizeof x))				\
	    if (rOBJ->rdrfnc)				\
		(*rOBJ->rdrfnc)(&x);			\
	return x;					\
    }							\
							\
    OBJrandomloc(type) OBJrandomloc(type)::operator=(	\
	type newobj)					\
    {							\
	if (!eputobj(rOBJ->rfp, thisoffset,		\
		     &newobj, sizeof newobj))		\
	    if (rOBJ->wtrfnc)				\
		(*rOBJ->wtrfnc)(&newobj);		\
	return *this;					\
    }							\
							\
    OBJrandomloc(type) OBJrandomloc(type)::operator=(	\
				 OBJrandomloc(type) r)	\
    {							\
	return (*this = (type) r);			\
    }
#endif /* RANDACCESS_H */
!EOF!
ls -l rc.h
echo x - rctst.c
sed 's/^X//' > rctst.c << '!EOF!'
/* Copyright (c) 1990 by AT&T Bell Telephone Laboratories, Incorporated. */
/* The C++ Answer Book */
/* Tony Hansen */
/* All rights reserved. */
#include <stream.h>
#include <ctype.h>

struct INT {
    char x[4];
};

#define XXXXOBJ INT
#include "../8.10dir/pr.c"

#include "rc.h"
declare(randomOBJ,INT);
implement(randomOBJ,INT);

#include "../8.9dir/8_9a2.c"
#include "../8.9dir/8_9a3.c"
#include "../8.10dir/8_10a4.c"
#include "../8.10dir/8_10a5.c"

int main(int, char**)
{
    randomOBJ(INT) x("tst.data");

    INT i = x[3];
    pr("x[3] = ", i);

    i = x[2];
    pr("x[2] = ", i);

    i.x[0] = '3';
    i.x[1] = ';';
    pr("i = ", i);
    x[1] = i;
    cout << "assigned x[1] <- i('3;')\n";

    x[0] = x[8];
    cout << "assigned x[0] <- x[8]\n";
    i = x[8];
    pr("x[8] = ", i);
    i = x[0];
    pr("x[0] = ", i);
    return 0;
}
!EOF!
ls -l rctst.c
echo x - tst.cmp
sed 's/^X//' > tst.cmp << '!EOF!'
x[3] = 10,111(o),116(t),104(h)
x[2] = 114(r),111(o),111(o),116(t)
i = 51(3),59(;),111(o),116(t)
assigned x[1] <- i('3;')
assigned x[0] <- x[8]
x[8] = 111(o),116(t),44(,),98(b)
x[0] = 111(o),116(t),44(,),98(b)
!EOF!
ls -l tst.cmp
echo x - tst.data
sed 's/^X//' > tst.data << '!EOF!'
ot,b3;otroot
other::1:
bin::2:root,bin,daemon
sys::3:root,bin,sys,adm
adm::4:root,adm,daemon
uucp::5:root,uucp
mail::6:root
daemon::12:root,daemon
docx::21:pcor,russak,mds,dsl,jeremy,bwp,hansen,coleman,chu,jack
guest::22:
!EOF!
ls -l tst.data
echo x - tst.save
sed 's/^X//' > tst.save << '!EOF!'
root::0:root
other::1:
bin::2:root,bin,daemon
sys::3:root,bin,sys,adm
adm::4:root,adm,daemon
uucp::5:root,uucp
mail::6:root
daemon::12:root,daemon
docx::21:pcor,russak,mds,dsl,jeremy,bwp,hansen,coleman,chu,jack
guest::22:
!EOF!
ls -l tst.save
echo x - tst2.cmp
sed 's/^X//' > tst2.cmp << '!EOF!'
ot,b3;otroot
other::1:
bin::2:root,bin,daemon
sys::3:root,bin,sys,adm
adm::4:root,adm,daemon
uucp::5:root,uucp
mail::6:root
daemon::12:root,daemon
docx::21:pcor,russak,mds,dsl,jeremy,bwp,hansen,coleman,chu,jack
guest::22:
!EOF!
ls -l tst2.cmp
# The following exit is to ensure that extra garbage 
# after the end of the shar file will be ignored.
exit 0