Solved–Assignment 9 — Solution

Description

*Overview*

In this assignment, you will write 2 macros. These will be tested with a
driver program that will be provided.

You may find it useful to examine the material on macros in the
textbook, Chapter 9, or on various web pages.

Document your macros completely.

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*Macros*

The first macro is called STRCPY. Its purpose is to make a copy of a
C-style string.

A C-style string is the type of character string used in the C language.
It is stored as a sequence of consecutive bytes and ends with a byte
containing X’00’.

STRCPY has two symbolic parameters:

* &SOURCE is the address of a C-style string of some length.

* &DEST is the address to which we want to copy the string.

Each of these addresses may be a label or a D(B) expression.

It is the responsibility of the user to ensure that the string is
terminated properly with X’00’ and that the destination is large enough
to hold the value.

The STRCPY macro should verify that each of its mandatory symbolic
parameters is present. If a parameter is missing, the macro should print
an informative error message using MNOTE and then MEXIT.

The STRCPY macro should not change the value of any of its parameters.

The simplest way to implement STRCPY is to copy one byte at a time in a
loop until the value X’00’ is found. That value should also be copied.

The second macro is called _SEARCH_. Its purpose is to make it easier to
use TRT. to search a character variable.

SEARCH has four symbolic parameters, all positional:

* &STR is the label of a character value to be searched.

* &LEN is the length of the character variable.

* &TABLE is the label of a 256-byte space we will use to create a
search table.

* &LIST is a sublist in which each item is an immediate byte.

The SEARCH macro should verify that each of its mandatory symbolic
parameters is present. If a parameter is missing, the macro should print
an informative error message using MNOTE and then MEXIT. If &LIST is an
empty list (as in ‘()’), use an MNOTE to announce this fact and do
nothing else.

If &LIST is not empty, the SEARCH macro will do the following:

* Initialize all of &TABLE to X’00’.
* For each value in &LIST, change the corresponding entry in &TABLE to
X’FF’.
* Use TRT to search &STR with the search table &TABLE.

The SEARCH macro should not change any register values except for
registers 1 and 2, which are affected by TRT. If &LIST is empty,
registers 1 and 2 should also be unchanged.

The SEARCH macro will set the condition code (if &LIST is empty).

You will probably need to use a local arithmetic variable and the length
attribute. You will probably find MVI useful.

Notice that the values of &STR and &TABLE may not be D(B) addresses.
This is just a convenience. We could manage with D(B) addresses.

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*Job Control Language*

Use the following Job Control Language (JCL) to execute Assignment 9 The
fields described in lower case are the same as described in Chapter 2 of
your _Notes and Examples_ book. This JCL combines your macros with the
driver program.

The driver program is a _complete_ program. It begins with CSECT and
ends with END. Do not supply _anything_ other than your two macros.

//jobname JOB ,’your name’,MSGCLASS=H
//STEP1 EXEC PGM=ASSIST,PARM=’MACRO=F’
//STEPLIB DD DSN=KC02293.ASSIST.LOADLIB,DISP=SHR
//SYSPRINT DD SYSOUT=*
//SYSIN DD *
Your Macros go here. Each Macro must begin with
MACRO and a Prototype statement. Your model
statements follow and the Macro ends with MEND.
(You should remove these four lines.)
// DD DSN=KC02314.SPRING18.CSCI360.HW9.DRIVER,DISP=SHR
//FT05F001 DD DUMMY
//FT06F001 DD SYSOUT=*
//