ISO/IEC 13719-1:1995
(Main)Information technology — Portable Common Tool Environment (PCTE) — Part 1: Abstract specification
Information technology — Portable Common Tool Environment (PCTE) — Part 1: Abstract specification
Technologies de l'information — Environnement d'outil courant portable (PCTE) — Partie 1: Spécifications abstraites
General Information
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Standards Content (Sample)
I N TE R NAT I O NA L
ISOJIEC
STANDARD
13719-1
First edition
1995-06-01
Information technology - Portable
Common Tool Environment (PCTE) -
Part 1:
Abstract specification
Technologies de l’information - Environnement d’outil courant portable
(PCTE) -
Partie I: Spécification d’abstrait
Reference number
ISO/IEC 13719-1 :1995(E)
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ISO/IEC 13719-1:1995(E)
Contents
1
Scope
1
Conformance
1
2.1 Conformance of binding
2.2 Conformance of implementation
20
3
Normative references
3
Definitions
3
4.1 Technical terms
4
4.2 Other terms
4
Formal notations
4
Overview of PCTE
6.1 PCTE structural architecture 5
6.2 Object management system 5
6.3
Object base
6 5~
6.4 Schema management
6
6.5 Self-representation and predefined SDSs
6.6 Object contents 6
6.7 Process execution 7
6.8 Monitoring 7
6.9 Communication between processes 7
6.10 Notification
7
6.11 Concurrency and integrity control 7
0 ISO/IEC 1995
All rights reserved. Unless otherwise specified, no part of this publication may be
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photocopying and microfilm, without permission in writing from the publisher.
HSO/IEC Copyright Office Case postale 56 CH-121 1 Genève 20 * Switzerland
Printed in Switzerland
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0 ISO/IEC
ISOBEC 13'719-f:1995(E)
6.12 Distribution
6.13 Replication
6.14 Security
6.15 Accounting
6.16 Implementation limits
7
Outline of ISO/IEC 13719
9
8 Foundation
10
8.1 The state
10
8.2 The object base
11
8.2.1 Objects
11
8.2.2 Attributes
12
8.2.3 Links
13
8.3 Types
14
8.3.1 Object types
14
8.3.2 Attribute types
15
8.3.3 Link types
16
8.3.4 Enumeral types
19
8.4 Types in SDS
19
8.4.1 Object types in SDS
21
8.4.2 Attribute types in SDS
21
8.4.3 Link types in SDS
22
8.4.4 Enumeral types in SDS
22
8.5 Types in working schema
22
8.5.1 Object types in working schema
23
8.5.2 Attribute types in working schema
23
8.5.3 Link types in working schema
24
8.5.4 Enumeral types in working schema
24
8.6 Types in global schema
24
m
8.7
Operations
25
8.7.1 Calling process
25
8.7.2 Direct and indirect effects
25
8.7.3 Errors
27
8.7.4 Operation serializability
28
9 Object management
28
9.1 Object management concepts
28
9.1.1 The basic type "object"
28
9.1.2 The common root
31
9.1.3 Datatypes for object management
32
9.2 Link operations
32
9.3 Object operations
40
9.4 Version operations
53
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ISO/IEC 13719-1: 1995(E)
0 ISO/IEC
59
1 O Schema management
59
10.1 Schema management concepts
10.1.1 Schema definition sets and the SDS directory 59
10.1.2 Types 60
61
10.1.3 Object types
61
10.1.4 Attribute types
63
10.1.5 Link types
10.1.6 Enumeral types 64
10.1.7 Datatypes for schema management 64
64
10.2 SDS update operations
89
10.3 SDS usage operations
10.4 Working schema operations 96
11 Volumes, devices, and archives 100
1 1.1 Volume, device, and archiving concepts 100
11.1.1 Volumes 100
101
1 1.1.2 Administration volumes
1 1.1.3 Devices 102
1 1.1.4 Archives 102
1 1.2 Volume, device, and archive operations 103
12 Files, pipes, and devices 110
12.1 File, pipe, and device concepts 110
12.2 File, pipe, and device operations
113
13 Process execution 120
13.1 Process execution concepts
120
13.1.1 Static contexts
120
13.1.2 Foreign execution images 121
13.1.3 Execution classes 121
13.1.4 Processes
122
13.1.5 Initial processes
128
13.1.6 Profiling and monitoring concepts
129
13.2 Process execution operations
129
13.3 Security operations
141
13.4 Profiling operations
146
13.5 Monitoring operations
147
14 Message queues
149
14.1 Message queue concepts
149
14.2 Message queue operations
151
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O ISO/IEC ISO/IEC 13719-1:1995(E)
157
15 Notification
157
15.1 Notification concepts
157
15.1.1 Access events and notifiers
158
15.1.2 Notification messages
158
15.1.3 Time of sending notification messages
158
15.1.4 Range of concerned message queues
159
1 5.2 Notification operations
160
16 Concurrency and integrity control
160
Concurrency and integrity control concepts
16.1
160
16.1.1 Activities
162
16.1.2 Resources and locks
164
16.1.3 Lack modes
166
16.1.4 Inheritance of locks
167
16.1.5 Establishment and promotion of locks
168
16.1.6 Implied locks
169
16.1.7 Conditions for establishment or promotion of a lock
169
16.1.8 Releasing locks
170
16.1.9 Permanence of updates
170
16.1.10 Tables for locks
173
Concurrency and integrity control operations
16.2
178
17 Replication
178
17.1 Replication concepts
178
17.1.1 Replica sets
179
17.1.2 Replicated objects
180
of an appropriate replica
17.1.3 Selection
181
17.1.4 Administration replica set
181
17.2 Replication operations
187
18 Network connection
187
18.1 Network connection concepts
187
18.1.1 Execution sites
187
18.1.2 Workstations
190
18.1.3 Foreign systems
190
18.1.4 Network partitions
191
18.1.5 Accessibility
192
18.1.6 Workstation closedown
193
18.2 Network connection operations
198
18.3 Foreign system operations
199
18.4 Time operations
200
19 Discretionary security
200
19.1 Discretionary security concepts
200
19.1.1 Security groups
203
19.1.2 Access control lists
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206
19.1.3 Discretionary access modes
208
19.1.4 Access control lists on object creation
209
19.2 Operations for discretionary access control operation
212
19.3 Discretionary security administration operations
217
2 O Mandatory security
217
20.1 Mandatory security concepts
217
20.1.1 Mandatory classes
218
20.1.2 The mandatory class structure
219
20.1.3 Labels and the concept of dominance
220
20.1.4 Mandatory rules for information flow
224
20.1.5 Multi-level security labels
226
20.1.6 Floating security levels
228
20.1.7 Implementation restrictions
228
20.1.8 Built-in policy aspects
230 a
20.2 Operations for mandatory security operation
235
20.3 Mandatory security administration operations
239
20.4 Mandatory security operations for processes
241
21 Auditing
24 1
2 1.1 Auditing concepts
24 1
2 1.1.1 Audit files
243
21.1.2 Audit selection criteria
2 1.2 Auditing operations 244
2 2 Accounting 248
22.1 Accounting concepts 248
22.1.1 Consumers and accountable resources
248
22.1.2 Accounting logs and accounting records 249
22.2 Accounting administration operations 0
252
22.3 Consumer identity operations 257
23 Common binding features
257
23.1 Mapping of types
257
23.1.1 Mapping of predefined PCTE datatypes
257
23.1.2 Mapping of designators and nominators
260
23.1.3 Mapping of other values
266
23.2 Object reference operations
267
23.3 Link reference operations
269
23.4 Type reference operations
272
2 4 Implementation limits
274
24.1 Bounds on installation-wide limits
274
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24.2 Bounds on workstation-dependent limits 275
Annex A (normative) VDM Specification Lnaguage for the abstract specification 278
Annex B (normative) The Data Definition Language (DDL) 283
Annex C (normative) Specification of errors 292
Annex D (normative) Auditable events 311
Annex E (informative) The predefined schema definition sets 318
Index of Error Conditions
337
Index of Technical Terms 344
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ISO/IEC 13719-1: 1995(E) O ISO/IEC
~ Foreword
IS0 (the International Organization for Standardization) and IEC (the Inter-
national Electrotechnical Commission) form the specialized system for worldwide
standardization. National bodies that are members of IS0 or IEC participate in the
development of International Standards through technical committees established
by the respective organization to deal with particular fields of technical activity.
IS0 and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with
IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint
technical committee, ISO/IEC JTC 1. Draft International Standards adopted by the
joint technical committee are circulated to national bodies for voting. Publication
% of the national
as an International Standard requires approval by at least 75
bodies casting a vote.
International Standard ISOAEC 137 19-1 was prepared by the European Computer
Manufacturers Association (ECMA) (as Standard ECMA- 149) and was adopted,
~
under a special “fast-track procedure”, by Joint Technical Committee ISOAEC
‘
STC 1, Information technology, in parallel with its approval by national bodies of
IS0 and IEC.
ISO/IEC 13719 consists of the following parts, under the general title Information
technology - Portable Common Tool Environment (PCTE):
- Part 1: Abstract specification
- Part 2: C programming language binding
- Part 3: Ada programming language binding
Annexes A to D form an integral part of this part of ISOAEC. Annex E is for
information only.
..I
VllP
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INTERNATIONAL STANDARD O ISO/IEC ISO/IEC 13719-1 1995(E)
Information technology - Portable Common Tool
Environment (PCTE) -
Part 1:
Abstract specification
1 Scope
This part of ISO/IEC 137 19 specifies PCTE in abstract, programming-language-independent, terms.
It specifies the interface supported by any conforming implementation as a set of abstract operation
specifications, together with the types of their parameters and results. It is supported by a number
of standard bindings, i.e. representations of the interface in standard programming languages.
The scope of this part of ISO/IEC 13719 is restricted to a single PCTE installation. It does not
specify the means of communication between PCTE installations, nor between a PCTE installation
and another system.
A number of features are not completely defined in this part of ISO/IEC 13719, some freedom being
allowed to the implementor. Some of these are implementation limits, for which constraints are
defined (see clause 24). The other implementation-dependent and implementation-defined features
are specified in the appropriate places in this part of ISO/IEC 13719 .
PCTE is an interface to a set of facilities that forms the basis for constructing environments
supporting systems engineering projects. These facilities are designed particularly to provide an
infrastructure for programs which may be part of such environments. Such programs, which are
used as aids to systems development, are often referred to as tools.
2 Conformance
2.1 Conformance of binding
A binding conforms to this part of ISO/IEC 13719 if and only if:
- it consists of a set of operational interfaces and datatypes, with a mapping from the operations
and datatypes of this part of ISODEC 137 19 ;
- each operation of this part of ISODEC 13719 is mapped to one or more sequences of one or
more operations of the binding (distinct operations need not be mapped to distinct sets of
sequences of binding operations);
- each datatype of this part of ISO/IEC 137 19 is mapped to one or more datatypes of the binding;
- each named error of this part of ISODEC 13719 is mapped to one or more error values (status
values, exceptions, or the like) of the binding;
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- the conditions of clause 23 on common binding features are satisfied;
- the conditions for conformance of an implementation to the binding are defined, are achievable,
and are not in conflict with the conditions in 2.2 below.
2.2 Conformance of implementation
The functionality of PCTE is divided into the following modules:
- The core module consists of the datatypes and operations defined in clauses 8 to 19 (except
13.1.6, 13.4, and 13.5) and 23.
- The mandatory access control module consists of the datatypes and operations defined in clause
20.
- The auditing module consists of the datatypes and operations defined in clause 21.
- The accounting module consists of the datatypes and operations defined in clause 22.
- The profiling module consists of the datatypes defined in 13.1.6 and the operations defined in
13.4.
- The monitoring module consists of the datatype Address defined in 13.1.6 and operations
defined in 13.5.
An implementation of PCTE conforms to this part of ISO/IEC 137 19 if and only if it implements
the core module.
An implementation of PCTE conforms to this part of ISO/IEC 13719 with mandatory access
control level 1 or 2 if it implements the core module and in addition:
- for level 1: the mandatory access control module except the floating security levels features
defined in 20.1.6;
- for level 2: the mandatory access control module.
An implementation of PCTE conforms to this part of ISODEC 13719 with auditing if and only if it
implements the core module and in addition the auditing module.
An implementation of PCTE conforms to this part of ISODEC 13719 with accounting if and only if
it implements the core module and in addition the accounting module.
An implementation of PCTE conforms to this part of ISODEC 137 19 with profiling if and only if it
implements the core module and in addition the profiling module.
An implementation of PCTE conforms to this part of ISODEC 13719 with monitoring if and only if
it implements the core module and in addition the monitoring module.
By 'an implementation implements a module' is meant that, for the clauses of the module:
- the implementation conforms to a binding of this part of ISO/IEC 13719 which itself conforms
to this part of ISODEC 13719 and which is itself an International Standard;
- if an operation of this part of ISO/IEC 13719 is mapped to a set of sequences of operations in
the binding:
. case 1 : operation-A; 0peration-B; . operation-F;
. case 2: operation-G; operation-H; . operation-M;
. etc.
then in each case the sequence of invocations of the operations of the implementation must have
the effect of the original operation of this part of ISODEC 13719;
- the relevant limits on quantities specified in clause 24 are no more restrictive than the values
specified there;
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- the implementations of the implementation-defined features in this part of ISODEC 13719 are all
defined.
An implementation of PCTE does not conform to this part of ISODEC 13719 if it implements any
of the following, whether or not the PCTE entity mentioned is in a module which the
implementation implements:
- an operation with same name as a PCTE operation but with different effect;
- an SDS with the same name as a PCTE predefined SDS but with different contents;
- an error condition with the same name as a PCTE error condition but with different meaning.
3 Normative references
The following standards contain provisions which, through reference in this text, constitute
provisions of this part of ISODEC 13719. At the time of publication, the editions indicated were
valid. All standards are subject to revision, and parties to agreements based on this International
Standard are encouraged to investigate the possibility of applying the most recent editions of the
Members of IEC and IS0 maintain registers of currently valid
standards indicated below.
International Standards.
ISODEC 2022 : 1994, Information technology - Character code structure and extension
techniques.
IS0 8601 : 1988, Data elements and interchange formats -Information interchange -
Representation of dates and times.
IS0 885 1 : 1987, Information processing - 8-bit single-byte coded graphic character sets
-Part 1 : Latin alphabet No. 1.
0646- 1 : 1993, Information technology - Universal Multiple-Octet Coded Character Set
ISODEC
(UCS) - Part 1: Architecture and Basic Multilingual Plane.
ISODEC 1404 : ---I), Information technology -Programming languages, their environments
and system software interfaces - Language-independent datatypes.
Information technology -Programming languages, their environments
ISO/IEC 13303- : -I),
and system software interJCaces - Vienna Development
Method/Specification language - Part I : Basic Language.
BS 6145 : 1981 Method of Defining Syntactic Metalanguage.
4 Definitions
4.1 Technical terms
All technical terms used in this part of ISODEC 13719, other than a few in widespread use, are
defined in the text, usually in a formal notation. All identifiers defined in VDM-SL or in DDL (see
5.2) are technical terms; apart from those, a defined technical term is printed in italics at the point of
its definition, and only there. For the use of technical terms defined in VDM-SL and DDL see
clause A.3 and clause B.9 respectively. All defined technical terms are listed in an index, with
references to their definitions.
1) To be published.
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4.2 Other terms
For the purposes of this International Standard, the following definitions apply.
4.2.1 implementation-defined: Possibly differing between PCTE implementations, but
defined for any particular PCTE implementation.
4.2.2 implementation-dependent: Possibly differing between PCTE implementations and
not necessarily defined for any particular PCTE implementation.
4.2.3 binding-defined: Possibly differing between language bindings, but defined for any
particular language binding.
4.2.4 datatype: The type of a parameter or result of an operation defined in this part of ISO/IEC
13719, or used to define such a type. Where, as in clause 23, it is necessary to distinguish these
types from datatypes defined elsewhere, the term PCTE datatype is used.
5 Formal notations
Four formal notations are used in this part of ISO/IEC 13719.
For datatypes and for operation signatures, a small subset of the Vienna Development Method
Specifîcation Language or VDM-SL is used; it is defined in annex A. This subset of VDM-SL is
also used to define some types used for operation parameters and results.
The Data Definition Language or DDL is used to define types; it is defined in annex B. Where a
concept is defined in both VDM-SL and DDL, the same identifier is used.
To define the error conditions detected by operations, a parameterized notation is used; it is defined
in annex C.
The BSI syntactic notation (BS 6154 : 1981) is used to define the syntax of VDM-SL and DDL,
and in a few other places where the syntax of strings is defined.
6 Overview of PCTE
PCTE is designed to support program portability by providing machine-independent access to a set
of facilities. These facilities, which are described in ISO/IEC 13719, are designed particularly to
provide an infrastructure for programs to support systems engineering projects.
The PCTE architecture is described in two dimensions: the structural architecture and thefunctional
architecture. The structural architecture is described in 6.1, and shows how a PCTE installation is
built of a system of communicating workstations and how the software providing the PCTE
interfaces is structured. The functional architecture is described in 6.2 onwards, and gives an
outline of the functional components of PCTE and the facilities they provide.
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6.1 PCTE structural architecture
The preferred structural architecture for a PCTE installation is a set of workstations and associated
resources communicating over a network, though other architectures are possible. There is no
hierarchy or ordering of workstations within a PCTE installation. If a workstation is part of a
PCTE installation then the PCTE installation appears to the workstation's user as a conceptually
single machine, although each workstation can act as an autonomous unit. Such a user has access
to the total resources of a PCTE installation, subject to the necessary access controls.
The PCTE database (called the object base) is partitioned into volumes. Volumes are dynamically
allocated to (mounted on) particular workstations, and, once mounted, are globally available in that
PCTE installation.
The program writer does not need to be aware of the distribution architecture, but the PCTE
interfaces do provide all the facilities needed to configure a PCTE installation and control its
distribution. The PCTE interfaces appear to the tool writer as available within a PCTE installation
irrespective of the tool's physical location within a PCTE installation and independent of any
particular network topology.
6.2 Object management system
An aspect of PCTE that is of major importance to the process of constructing and integrating
portable tools is the provision of the object base and a set of functions to manipulate the various
objects in the object base. The object base is the repository of the data used by the tools of a PCTE
installation, and the Object Management System or OMS of PCTE provides the functions used to
access the object base.
In a general sense, the users and programs of the PCTE installation have the ability to manage
entities that are known to, and can be designated in, a particular PCTE installation. These may be
files in the traditional sense, or peripherals, interprocess message queues or pipes, or the
description of processes themselves or of the static context of a process. Tools supporting user
applications establish classes of objects defined by the user: these can represent information items
such as project milestones, tasks, and change requests.
6.3 Object base
The basic OMS model is derived from the Entity Relationship data model and defines objects and
links as being the basic items of a PCTE object base,
Objects are entities (in the Entity Relationship sense) which can be designated, and can optionally
have:
- Contents: a storage of data representing the traditional file concept;
- Attributes: primitive values representing specific properties of an object which can be named
individually;
- Links: representations of associations between objects. Links may have attributes, which may
be used to describe properties of the associations or as keys to distinguish between links of the
same type from the same object.
Designation of links is the basis for the designation of objects: the principal means for accessing
objects in most OMS operations is to navigate the object base by traversing a sequence of links.
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6.4 Schema management
Entities used by the user and those used by the system that are represe ted by objects in the object
base can be treated in a uniform manner, and facilities to control their structure, to store and to
designate these objects, are provided by PCTE.
The object base of each PCTE installation is governed by a typing mechanism. All entities in the
object base are typed and the data must conform to the corresponding type rules. Type rules are
defined for objects, for links, and for attributes.
PCTE is designed to allow, but not to require, distributed and devolved management of the object
base. To this end the definition of the typing rules which govern an object, a link, or an attribute in
the object base may be split up among a number of schema definition sets (or SDSs). Some
an object, a link, or an attribute must be the same in every SDS which contributes to
properties of
the definition of the typing rules for that object, link, or attribute: these are properties of the type.
Other properties may differ for different SDSs: these are properties of the type in SDS.
Each SDS provides a consistent and self-contained view of the data in the object base. A process,
at any one time, views the data in the object base through a working schema. A working schema is
obtained as a composition of SDSs in an ordered list. The effect of such a composition is to
provide a union of all the types contained in the listed SDSs. A uniform naming algorithm,
dependent on the ordering of the SDSs, is applied to all the contained types.
The object base of a PCTE installation has a notional global schema, composed of all the SDSs.
The global schema is not directly represented in the object base, and the concept is used mainly to
state certain consistency constraints on the object base as a whole.
Child types of object types can be defined with the effect of implicit inheritance of all properties of
their parent types. Additionally, child types can have properties of their own.
6.5 Self-representation and predefined SDSs
Many of the entities in a PCTE installation are represented by objects in the object base. The types
of these objects are defined in predefined SDSs, which are available in any conforming
implementation; for example processes are represented by objects of type "process" which is
defined in the predefined SDS 'system'. This property of PCTE is called self-representation. In
general, in this part of ISO/IEC 137 19, the name of an entity is used also to refer to the object that
represents it.
In some cases an object of a type representing some kind of entity requires initializing, or must be
it can be used in operations to represent an entity of that
created by a particular operation, before
kind. Such an object which has been initialized or correctly created is referred to as a known entity
of that kind (i.e. known to the PCTE installation); any other object of that type is referred to as an
unknown entity. For example an object of type "process" created by PROCESS-CREATE is a
known process, while one created by OBJECTCREATE is an unknown process.
6.6 Object contents
A set of operations is provided to access the contents of some types of objects (files, pipes, and
devices). These operations provide conventional input-output facilities on files and pipes and
control of input and output on devices. These contents are not interpreted by PCTE.
Other types of objects (accounting logs and audit files) have contents with structure that is defined
by PCTE and for access to which special operations are provided.
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6.7 Process execution
PCTE is an interface to support programs. When a program is run, this is either the execution of
the program itself, or the execution of an interpreter which interprets the program. An execution of
a program is aprocess. Processes are represented by objects in the object base, so the hierarchy of
processes, the environment in which a process runs, the parameters it has been passed, and the
various stages of the program execution can be controlled, manipulated and examined.
These facilities can be used also to control processes running on foreign systems. A foreign
system can be a foreign development system, a target system running a real-time operating system,
or even a PCTE workstation in another PCTE installation.
6.8 Monitoring
PCTE provides three sets of features to support debugging and monitoring of processes.
- To measure the amount of time spent in selected parts of the code.
- To observe, and modify, the execution of a child process.
- To measure the processor usage of the calling process.
6.9 Communication between processes
PCTE provides a number of different mechanisms for communicating between processes. The
principal ones supplied are:
- the objects, links and attributes in the database;
- message queues;
- pipes.
Message queues and pipes are essentially special forms of object. Thus both pipes and message
queues are special cases of the general use of the object base for interprocess communication.
Pipes and message queues also provide communication between PCTE processes and foreign
processes running on foreign systems (if the foreign systems allow it).
6.10 Notification
In PCTE there is a mechanism that allows the designation of objects so that certain types of access
in a message queue which can be accessed by the process
result in a message being posted
requesting the notification.
The notification mechanism allows a process to specify events, corresponding to operations on
objects, of which it wants to be notified.
6.11 Concurrency and integrity control
The object base is subject to concurrent access by users, and is liable to underlying system failure.
PCTE provides locking facilities to control the strength of object base concurrency and consistency,
ranging from unprotected behaviour, through protected behaviour, to protected atomic and
serializable transaction activities. PCTE ensures object base consistency and object base integrity
for atomic and serializable transactions.
Each user carrying out a transaction on the object base sees some grouping of operations as an
atomic operation which transforms the object base from one consistent state to another. If
transactions are run one at a time then each transaction sees the consistent state left by its
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O ISO/IEC
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predecessor. When transactions are run concurrently PCTE ensures that the effect on the object
base is as though they were run serially. With a few exceptions, such as messages sent to or
received from a message queue, the effect of a sequence of operations performed within a
tran
...
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