1、 International Telecommunication Union ITU-T Z.164TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (05/2012) SERIES Z: LANGUAGES AND GENERAL SOFTWARE ASPECTS FOR TELECOMMUNICATION SYSTEMS Formal description techniques (FDT) Testing and Test Control Notation (TTCN) Testing and Test Control Notation ve
2、rsion 3: TTCN-3 operational semantics Recommendation ITU-T Z.164 ITU-T Z-SERIES RECOMMENDATIONS LANGUAGES AND GENERAL SOFTWARE ASPECTS FOR TELECOMMUNICATION SYSTEMS FORMAL DESCRIPTION TECHNIQUES (FDT) Specification and Description Language (SDL) Z.100Z.109 Application of formal description technique
3、s Z.110Z.119 Message Sequence Chart (MSC) Z.120Z.129 User Requirements Notation (URN) Z.150Z.159 Testing and Test Control Notation (TTCN) Z.160Z.179PROGRAMMING LANGUAGES CHILL: The ITU-T high level language Z.200Z.209 MAN-MACHINE LANGUAGE General principles Z.300Z.309 Basic syntax and dialogue proce
4、dures Z.310Z.319 Extended MML for visual display terminals Z.320Z.329 Specification of the man-machine interface Z.330Z.349 Data-oriented human-machine interfaces Z.350Z.359 Human-machine interfaces for the management of telecommunications networks Z.360Z.379 QUALITY Quality of telecommunication sof
5、tware Z.400Z.409 Quality aspects of protocol-related Recommendations Z.450Z.459 METHODS Methods for validation and testing Z.500Z.519 MIDDLEWARE Processing environment architectures Z.600Z.609 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T Z.164 (05/2012) i Recomm
6、endation ITU-T Z.164 Testing and Test Control Notation version 3: TTCN-3 operational semantics Summary Recommendation ITU-T Z.164 defines the operational semantics of TTCN-3 (Testing and Test Control Notation 3). The operational semantics are necessary to unambiguously interpret the specifications m
7、ade with TTCN-3. This Recommendation is based on the TTCN-3 core language defined in Recommendation ITU-T Z.161. This second revision of the Recommendation contains amendments, clarifications, corrigenda and editorial corrections. This Recommendation is technically aligned with ETSI ES 201 873-4 V4.
8、4.1 (2012). History Edition Recommendation Approval Study Group 1.0 ITU-T Z.143 2006-03-16 17 2.0 ITU-T Z.164 2007-11-13 17 3.0 ITU-T Z.164 2011-03-16 17 4.0 ITU-T Z.164 2012-05-29 17 ii Rec. ITU-T Z.164 (05/2012) FOREWORD The International Telecommunication Union (ITU) is the United Nations special
9、ized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them wit
10、h a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Reco
11、mmendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for c
12、onciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recomm
13、endation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any par
14、ty. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property R
15、ights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implemen
16、ters are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written p
17、ermission of ITU. Rec. ITU-T Z.164 (05/2012) iii Table of Contents Page 1 Scope 1 2 References. 1 2.1 Normative references 1 2.2 Informative references 1 3 Definitions and abbreviations . 1 3.1 Definitions 1 3.2 Abbreviations . 1 4 Introduction 2 5 Structure of the present document 2 6 Restrictions
18、. 2 7 Replacement of short forms 3 7.1 Order of replacement steps . 3 7.2 Replacement of global constants and module parameters 4 7.3 Embedding single receiving operations into alt statements . 4 7.4 Embedding stand-alone altstep calls into alt statements 5 7.5 Replacement of interleave statements 5
19、 7.6 Replacement of trigger operations 18 7.7 Replacement of select-case statements . 19 7.8 Replacement of simple break statements . 20 7.9 Replacement of continue statements 21 7.10 Adding default parameters to disconnect and unmap operations without parameters . 21 7.11 Adding default values of p
20、arameters 22 8 Flow graph semantics of TTCN-3 22 8.1 Flow graphs 22 8.2 Flow graph representation of TTCN-3 behaviour 27 8.3 State definitions for TTCN-3 modules . 33 8.4 Messages, procedure calls, replies and exceptions . 45 8.5 Call records for functions, altsteps and test cases 48 8.6 The evaluat
21、ion procedure for a TTCN-3 module . 48 9 Flow graph segments for TTCN-3 constructs 50 9.1 Action statement . 51 9.2 Activate statement 51 9.2a Alive component operation 52 9.3 Alt statement . 55 9.4 Altstep call 62 9.5 Assignment statement . 62 iv Rec. ITU-T Z.164 (05/2012) Page 9.5a Break statement
22、s in altsteps 62 9.6 Call operation . 63 9.7 Catch operation . 70 9.8 Check operation 71 9.8a Checkstate port operation . 74 9.9 Clear port operation 77 9.10 Connect operation . 77 9.11 Constant definition . 78 9.12 Create operation 79 9.13 Deactivate statement . 80 9.14 Disconnect operation 82 9.15
23、 Do-while statement . 87 9.16 Done component operation . 88 9.17 Execute statement . 89 9.18 Expression 93 9.19 Flow graph segment 96 9.20 Flow graph segment . 96 9.20a Flow graph segment 97 9.20b Flow graph segment . 97 9.21 Flow graph segment . 98 9.22 Flow graph segment 98 9.23 For statement 99 9
24、.24 Function call . 100 9.25 Getcall operation 105 9.26 Getreply operation 105 9.27 Getverdict operation . 106 9.28 Goto statement 106 9.28a Halt port operation 107 9.29 If-else statement 107 9.29a Kill component operation . 108 9.29b Kill execution statement . 112 9.29c Killed component operation .
25、 114 9.30 Label statement . 115 9.31 Log statement . 116 9.32 Map operation . 116 9.33 Mtc operation 117 9.34 Port declaration . 117 9.35 Raise operation . 118 9.36 Read timer operation 121 9.37 Receive operation . 122 Rec. ITU-T Z.164 (05/2012) v Page 9.38 Repeat statement . 126 9.39 Reply operatio
26、n 127 9.40 Return statement . 130 9.41 Running component operation . 134 9.42 Running timer operation . 136 9.43 Self operation 138 9.44 Send operation 138 9.45 Setverdict operation 141 9.46 Start component operation 142 9.47 Start port operation . 143 9.48 Start timer operation . 144 9.49 Stop comp
27、onent operation 146 9.50 Stop execution statement 150 9.51 Stop port operation . 151 9.52 Stop timer operation . 152 9.53 System operation 153 9.53a Test case stop operation 154 9.54 Timer declaration 154 9.55 Timeout timer operation . 156 9.56 Unmap operation 156 9.57 Variable declaration 160 9.58
28、While statement 162 10 Lists of operational semantic components 163 10.1 Functions and states 163 10.2 Special keywords 166 10.3 Flow graphs of TTCN-3 behaviour descriptions 166 10.4 Flow graph segments 166 Rec. ITU-T Z.164 (05/2012) 1 Recommendation ITU-T Z.164 Testing and Test Control Notation ver
29、sion 3: TTCN-3 operational semantics 1 Scope This Recommendation defines the operational semantics of TTCN-3. The present document is based on the TTCN-3 core language defined in 1. 2 References References are either specific (identified by date of publication and/or edition number or version number
30、) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. Referenced documents which are not found to be publicly available in the expected location might be found at http:
31、/docbox.etsi.org/Reference. NOTE While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long-term validity. 2.1 Normative references The following ITU-T Recommendations and other references contain provisions which, through reference in this te
32、xt, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition
33、of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. 1 Recommendation ITU-T Z.161 (2012
34、), Testing and Test Control Notation version 3: TTCN-3 core language. ETSI ES 201 873-1 (2012), Methods for Testing and Specification (MTS); The Testing and Test Control Notation version 3; Part 1: TTCN-3 Core Language. 2.2 Informative references None. 3 Definitions and abbreviations 3.1 Definitions
35、 For the purposes of this Recommendation, the terms and definitions given in 1 apply. 3.2 Abbreviations For the purposes of this Recommendation, the following abbreviations apply: BNF Backus-Nauer Form MTC Master Test Component SUT System Under Test TTCN Testing and Test Control Notation 2 Rec. ITU-
36、T Z.164 (05/2012) 4 Introduction This clause defines the meaning of TTCN-3 behaviour in an intuitive and unambiguous manner. The operational semantics is not meant to be formal and therefore the ability to perform mathematical proofs based on this semantics is very limited. This operational semantic
37、s provides a state oriented view on the execution of a TTCN module. Different kinds of states are introduced and the meaning of the different TTCN-3 constructs is described by: 1) using state information to define the preconditions for the execution of a construct; and 2) defining how the execution
38、of a construct will change a state. The operational semantics is restricted to the meaning of behaviour in TTCN-3, i.e., functions, altsteps, test cases, module control and language constructs for defining test behaviour, e.g., send and receive operations, if-else-, or while- statements. The meaning
39、 of some TTCN-3 constructs is explained by replacing them with other language constructs. For example, interleave statements are short forms for series of nested alt statements and the meaning of each interleave statement is explained by its replacement with a corresponding series of nested alt stat
40、ements. In most cases, the definition of the semantics of a language is based on an abstract syntax tree of the code that shall be described. This semantics does not work on an abstract syntax tree but requires a graphical representation of TTCN-3 behaviour descriptions in form of flow graphs. A flo
41、w graph describes the flow of control in a function, alt step, test case or the module control. The mapping of TTCN-3 behaviour descriptions onto flow graphs is straightforward. NOTE The mapping of TTCN-3 statements onto flow graphs is an informal step and is not defined by using the BNF rules in 1.
42、 The reason for this is that the BNF rules are not optimal for an intuitive mapping because several static semantic rules are coded into BNF rules in order to allow static semantic checks during the syntax check. 5 Structure of the present document The present document is structured into four parts:
43、 1) The first part (see clause 6) describes restrictions of the operational semantics, i.e., issues related to the semantics, which are not covered by the present document. 2) The second part (see clause 8) defines the meaning of TTCN-3 short cut and macro notations by their replacement with other T
44、TCN-3 language constructs. These replacements in a TTCN-3 module can be seen as pre-processing step before the module can be interpreted according to the following operational semantics description. 3) The third part (see clause 9) describes the operational semantics of TTCN-3 by means of flow graph
45、 interpretation and state modification. 4) The fourth part (see clause 10) specifies the mapping of the different TTCN-3 statements onto flow graph segments, which provide the building blocks for flow graphs representing functions, alt steps, test cases and module control. 6 Restrictions The operati
46、onal semantics only covers behavioural aspects of TTCN-3, i.e., it describes the meaning of statements and operations. It does not provide: a) A semantics for the data aspects of TTCN-3. This includes aspects like encoding, decoding and the usage of data imported from non-TTCN-3 specifications. b) A
47、 semantics for the grouping mechanism. Grouping is related to the definitions part of a TTCN-3 module and has no behavioural aspects. Rec. ITU-T Z.164 (05/2012) 3 c) A semantics for the import statement. The import of definitions has to be done in the definitions part of a TTCN-3 module. The operati
48、onal semantics handles imported definitions as if they are defined in the importing module. 7 Replacement of short forms Short forms have to be expanded by the corresponding complete definitions on a textual level before this operational semantics can be used for the explanation of TTCN-3 behaviour.
49、 TTCN-3 short forms are: lists of module parameter, constant and variable declarations of the same type and lists of timer declarations; stand-alone receiving operations; stand-alone altsteps calls; trigger operations; missing return and stop statements at the end of function and test case definitions; missing stop execution statements; interleave statements; select-case statements; break and continue statements; disconnect and unmap operations without parameters; and default values
