TechTip: Analyze Your Programs and Applications, Part III

Tips & Techniques - System Administration

Written by Jean-Paul Lamontre

Friday, 10 August 2012 00:00

Fill the gap between modules and ILE programs for a full panorama of your ILE application.

Part I and Part II of this series have shown how some system commands can be used to dissect in depth one application, without the source code. But these analyses suffer from a lack of information for ILE programs-namely, the link between the program and embedded modules.

Indeed, for OPM programs, the command DSPOBJD provides a direct link between the program and source code. This is possible because the compiler goes directly from the source code to the program without going through an object module. Conversely, for ILE programs, DSPOBJD does not give such information. It cannot: ILE programs can be composed of several modules.

Although each module knows the name of its source code (and DSPOBJD knows how to find that), the link between a program and the list of modules is inaccessible: the command DSPPGM does not offer OUTPUT(*FILE).

This third article shows first the command RTVPGM, based on the six APIs shown below. This command and these APIs provide an OUTPUT(*FILE) equivalent to the output screens of DSPMOD, DSPPGM, and DSPSRVPGM. These OUTFILE outputs are a one-to-one relationship for most of the formats of these APIs.

Retrieve Module Information (QBNRMODI) API
Retrieve Program Information (QCLRPGMI) API
Retrieve Service Program Information (QBNRSPGM) API
List Module Information (QBNLMODI) API
List ILE Program Information (QBNLPGMI) API
List Service Program Information (QBNLSPGM) API

This article then shows the scripts used to extract information from these files.

The command RTVPGM explores objects of type * MODULE, * PGM, and * SRVPGM. It produces 16 files:

Three describe the basic information modules, programs, and service programs:

MODI0100-Basic module information
PGMI0100-Basic program information
SPGI0100-Basic service program information

Five to describe the attachment of modules:

MODL0100-Module export (*EXPORT) information
MODL0200-Module import (*IMPORT) information
MODL0300-Module procedures (*PROCLIST) information
MODL0400-Referenced system objects (*REFSYSOBJ) information
MODL0500-Module copyright (*COPYRIGHT) information

Five describe programs and service programs' attachments:

PGML0100-ILE program module (*MODULE) information
PGML0200-ILE service program (*SRVPGM) information
PGML0300-Data items exported to the activation group (*ACTGRPEXP)
PGML0400-Data item imports resolved by weak exports that were exported to the activation group (*ACTGRPIMP)
PGML0500-ILE program copyright (*COPYRIGHT) information

Three describe specific service programs' attachments:

SPGL0600-Procedure export information
SPGL0700-Data export information
SPGL0800-Signature information

Figures 1 through 3 show the three screens of the RTVPGM command

081012JpFig1

Figure 1: In RTVPGM page 1, choose the objects to analyze and the names for module information files

081012JpFig2

Figure 2: In RTVPGM page 2, choose the name for the program information files

081012JpFig3

Figure 3: In RTVPGM page 3, choose the name for the service program information files

These files by themselves are very interesting cross-references. For example, when a program crashes because of a service program (yes, it happens, especially in development), we can easily find out which procedure sent the error message (it's in F9 of the message), but how do we determine the name of the module that hosts this procedure? Is it the only one? MODL0300 provides the answer.

But back to the goal of this article: analyzing the structure of an ILE application. The difference is that here, with an ILE application, we must include the fact that a program consists of one or more modules and these modules have source code.

First, you will find below rewritten SQL to match some SQL from the previous article. I've done this because the previous SQL was prepared for a program, where source code name and module name are the same.

For an ILE program, there is no method to determine the list of modules within a program because DSPPGM does not have an OUTPUT(*OUTFILE). The modified SQL uses the OUTFILEs generated by RTVPGM to determine the list of the modules of any ILE program, irrespective of the number of modules.Depending on whether or not the *MODULE objects are available, we use either file MODI0100 or PGML0100. Finally, you will find SQL that gets the two or three pieces of information that were missing

Modules by Type and Year

This statistic concerns the counting of objects by type and year of source update:

*MODULE:

with stat as (
  SELECT MODULE_ATTR "Attribute" ,trim(char(substr(source_date,1,1) + 19) ) concat substr(SOURCE_DATE,2,2) "Year" 
  FROM jpltools.modi0100 
) select "Year" ,"Attribute" , count(*) Number 
  from stat 
  group by "Attribute", "Year" 
  order by "Year", "Attribute"

081012JpFig4

Figure 4: These are the modules by type and year

Note: No OPM program here; OPM does not produce *MODULE.

*PGM & *SRVPGM:

with stat as (
  SELECT MODULE_ATTR "Attribute" ,trim(char(substr(source_date,1,1) + 19) ) concat substr(SOURCE_DATE,2,2) "Year" 
  FROM jpltools.pgml0100 
) select "Year" ,"Attribute" , count(*) Number 
  from stat 
  group by "Attribute", "Year" 
  order by "Year", "Attribute"

081012JpFig5

Figure 5: These are the modules by type and year from programs

Note: No OPM here; that's discarded by RTVPGM.

Results are slightly different. These are some reasons:

1. Some programs need to be recompiled to include updated modules.
2. Some modules are not referenced.
3. Some modules are not available.

Source by Library

*MODULE:

SELECT count(*),SOURCE_LIB 
FROM jpltools.modi0100 
GROUP BY SOURCE_LIB

081012JpFig6

Figure 6: These are the sources by library from modules

*PGM & *SRVPGM:

SELECT count(*),SOURCE_LIB 
FROM jpltools.pgml0100 
GROUP BY SOURCE_LIB

081012JpFig7

Figure 7: These are the sources by library from programs

Sources by File

SELECT count(*),SOURCE_NAME 
FROM jpltools.modi0100 
GROUP BY SOURCE_NAME

081012JpFig8

Figure 8: These are the sources by file from modules

*PGM & *SRVPGM

SELECT count(*),SOURCE_NAME 
FROM jpltools.pgml0100 
GROUP BY SOURCE_NAME

081012JpFig9

Figure 9: These are the sources by file from programs

Objects by Version

SELECT count(*),RELEASE_MODULE_CREATED_FOR 
FROM jpltools.modi0100 
GROUP BY RELEASE_MODULE_CREATED_FOR

081012JpFig10
Figure 10: These are the objects by version from modules

*PGM & *SRVPGM:

SELECT count(*), RELEASE_FOR 
FROM jpltools.pgml0100 
GROUP BY RELEASE_FOR

081012JpFig11

Figure 11: These are the objects by version from programs

Objects by Owner

SELECT count(*),MODULE_OWNER 
FROM jpltools.modi0100 
GROUP BY MODULE_OWNER

081012JpFig12

Figure 12: These are the objects by owner from modules.

SELECT count(*),PROGRAM_OWNER 
FROM jpltools.pgmi0100 
GROUP BY PROGRAM_OWNER

081012JpFig13

Figure 13: These are the objects by owner from programs.

SELECT count(*), OWNER 
FROM jpltools.spgi0100 
GROUP BY OWNER

081012JpFig14

Figure 14: These are the objects by owner from service programs.

Check the Date of the Source Code

Reminder: MODI0100 or PGML0100 give us the exact date of the source code when compiling the module. DSPFD MBRLIST gives us the exact date of last modification of the source code.

Step one: Simplify the reading of DSPFD-MBRLIST (remember, the code is the same as in the previous article).

For the modification date of the source code:

SELECT MLNAME,case when MLCHGc = '' then ' ' else trim(char(MLCHGC+ 19)) concat MLCHGD concat MLCHGt end Upddate,MLMTXT 
FROM jpltools.mbrlist 
WHERE MLCHGc <> ''

081012JpFig15

Figure 15: Simplify reading DSPFD-MBRLIST

Step two: Simplify the reading of MODI0100.

For the compilation date of the source code:

SELECT src, srcmbr , case when srcdate = '' then ' ' else trim(char(substr(srcdate,1,1) + 19) ) concat substr( srcdate,2) end cpldate , modattr 
FROM jpltools.modi0100

081012JpFig16

Figure 16: Simplify the reading of MODI0100

The join of the two previous results (with SQL CTE - Common Table Expression) gives the list of modules without source:

with
obj as (
	SELECT 
		src, 
		srcmbr , 
		case when srcdate = '' then ' ' 
			  else trim(char(substr(srcdate,1,1) + 19) ) concat substr( srcdate,2) end cpldate , 
		modattr 
		FROM jpltools.modi0100 
) , src as (
	SELECT 
		MLNAME, 
		case when MLCHGc = '' then ' ' 
		     else trim(char(MLCHGC+ 19)) concat MLCHGD concat MLCHGt end Upddate,
		MLMTXT 
		FROM jpltools.mbrlist 
		WHERE MLCHGc <> ''
)	select src , srcmbr , cpldate, modattr 
	from obj exception join src on srcmbr = mlname

081012JpFig17

Figure 17: These are the modules without source

Find the list of sources that do not build a program directly-for example, code description of a service program or code of an SQL procedure or uncompiled code (i.e., copied code):

with obj as (
	SELECT srcfile, srcmbr , case when srcdate = '' then ' ' else trim(char(substr(srcdate,1 ,1) + 19) ) concat substr( srcdate,2)  end cpldate , modattr 
	FROM jpltools.pgml0100
) , src as (
	SELECT MLNAME, case when MLCHGc = '' then ' ' else trim(char(MLCHGC+ 19)) concat MLCHGD concat MLCHGt end Upddate,MLMTXT 
	FROMjpltools.mbrlist 
	WHERE MLCHGc <> ''
) 	select src.* from src src exception join obj on srcmbr = mlname

081012JpFig18

Figure 18: These are the sources without objects

Get the list of sources modified but not recompiled:

with obj as ( 
	SELECT src, srcmbr , case when srcdate = '' then ' ' else trim(char(substr(srcdate,1 ,1) + 19) ) concat substr( srcdate,2)  end cpldate , modattr , text 
	FROM jpltools.modi0100
) , src as ( 
	SELECT MLNAME, case when MLCHGc = '' then ' ' else trim(char( MLCHGC+ 19)) concat MLCHGD concat MLCHGt end Upddate,MLMTXT 
	FROM jpltools.mbrlist 
	WHERE MLCHGc <> '' 
) select 
	src "Object"
	, srcmbr "Src Mbr"
	, cpldate concat 
		case when upddate = cpldate then '' 
		     else ' was updated ' concat upddate end "Compiled_date" 
	, case when mlmtxt = text then ' ' concat text 
	       else '>> '  concat text concat ' changed to ' concat mlmtxt end  "Text" 
	from obj join src on srcmbr  = mlname and (cpldate <> upddate or text  <> mlmtxt)

081012JpFig19

Figure 19 : These sources were modified but not recompiled .

I changed my machine; we see the traces dated 2010-11-12-20:41:42.

Program Cross-References

These are based on DSPPGMREF output; that is to say on objects themselves, not on the source. Therefore, there is nothing to add to DSPPGMREF from the 16 files of RTVPGM. These analyses, exposed in the second article, are already accurate. They are not replicated here.

ILE Cross-References

ILE Cross-references are focused on module, procedure, program, and service program information received from RTVPGM outfiles. Their goal is to complete the data got from DSPPGMREF. Here, you will find a starter: the two SQLs needed to get the missing information quoted in previous articles:

Program by Activation Group:

 
select activation_group_attribute, count(*) count 
from jpltools.pgmi0100 
group by activation_group_attribute

081012JpFig20

Figure 20 : Get information about programs by activation group.

Monitor the Rights Acquisition:

select USER_profile_option, use_adopted_authority, count(*) count 
from jpltools.pgmi0100 
group by USER_profile_option, use_adopted_authority

081012JpFig21
Figure 21 : Monitor rights acquisition.

None of the programs in this application uses the owner authority. I don't need to further analyze which program runs under owner profile authority and check whether this is compliant with my policy rules. But if you need that information, you may want to quickly run an analysis:

	
SELECT program_name, program_library_name, program_owner 
FROM jpltools.pgmi0100 
WHERE USER_profile_option <>'U'

I'll stop here; there is so much information in these files! Depending on your own interests, you can now easily understand how your software is built. Now, it's up to you.

Jean-Paul Lamontre

About the Author:

Jean-Paul Lamontre has been working on IBM machines since 1976. His first was a 3/15 with 128K RAM (the biggest machine of the county). His first program was an RPG program, no more than 15 lines. It never compiled, and nobody ever understood why.

Currently, Jean-Paul divides has work time between two companies.

For Cilasoft, which offers the Cilasoft Audit and Security suite, he is the director of development. The Cilasoft suite is a cornerstore to any company's compliance process.

For Resolution, which offers Xcase, a database engineering suite, he is the CTO of the IBM i department. Xcase allows developers to modernize a DDS database to DDL, discover and implement implicit relationships, and manage SQL databases using an advanced GUI.

Jean-Paul also publishes some free tools on his personal Web site. Most popular are SQL2XLS, SPLF2PDF, and MAIL.