ATF-FORMATS(5)

NAME
atf-formats - machine-parseable data formats used by ATF

DESCRIPTION
This manual page describes the multiple data formats used in ATF. These formats affect configuration files, control files and any data that is externalized or internalized by the tools.

Data files are always organized as follows:

    Header1: Value1            \
        ...                    | head
    HeaderN: ValueN            /
                               mandatory blank line
    Free-form text contents    \
        ...                    | body
        ...                    /

A file must always contain a ‘Content-Type’ header and must always separate that header from the body with a blank line, even if the body is empty.

The ‘Content-Type’ is always of the form:

    Content-Type: application/X-atf-<subtype>; version="<version>"

where ‘subtype’ indicates the specific file format and ‘version’ its format version. This header must be the first one of the file.

The main purpose of the ‘Content-Type’ header, aside from determining the format used in the file, is to allow future changes to a given format. Whenever an incompatible change is made, the version is bumped by one. By keeping the header in the first line, future versions may even remove the need for such a header -- e.g. if some format was replaced by XML files, which have their own mandatory header.

The rest of this document details the different format types.

  Format: application/X-atf-atffile, version: 1
Atffiles are logically divided into three sections:

•   Test programs: the list of test programs that define the test suite described by the Atffile.

•   Meta-data properties: these define some constant values applicable to all the test programs defined in the file. In some sense they define the properties that describe the test suite.

•   Configuration variables: defaults for configuration variables that can be overridden through configuration files or the command line.

The grammar for Atffiles is the following:

    DATA ::= ( ( CONF | PROP | TP )? COMMENT? NEWLINE )* EOF
    CONF ::= 'conf:' WORD EQUAL STRING
    PROP ::= 'prop:' WORD EQUAL STRING
    TP ::= TPFILE | TPGLOB
    TPFILE ::= 'tp: ' STRING
    TPGLOB ::= 'tp-glob: ' STRING
    STRING ::= WORD | '"' WORD* '"'

The meaning of the constructions above is:

CONF
    Definition of a configuration variable.

PROP
    Definition of a meta-data property.

TPFILE
    Addition of a test program into the test suite. The string is taken literally as the program's name, and this program must exist.

TPGLOB
    Addition of multiple test programs into the test suite. The string is taken as a glob pattern, which may have or not have any matches in the current directory.

An example:

    prop: test-suite = utilities
    conf: unprivileged-user = nobody
    tp: t_cp
    tp: t_mv
    tp: t_df
    tp-glob: t_dir_*

  Format: application/X-atf-config, version: 1
Configuration files are very simple: they only contain a list of variable name/variable value pairs. Their grammar is:

    DATA ::= ( VAR? COMMENT? NEWLINE )* EOF
    VAR ::= WORD EQUAL STRING
    COMMENT ::= HASH WORD*
    STRING ::= WORD | '"' WORD* '"'

An example:

    # This is the system-wide configuration file for ATF.
    # The above and this line are comments placed on their own line.
    var1 = this is a variable value
    var2 = this is another one      # Optional comment at the end.

  Format: application/X-atf-tcs, version: 1
The ‘application/X-atf-tcs’ format is used to describe the results of a collection of test cases; in other words, it represents the output of a test program. Unfortunately, it is not easy to control, from inside a test program, what it prints to both its standard output and standard error streams. This is specially the case of test programs written in the POSIX shell language, because they are constantly executing external tools that may print unexpected messages at all times. Due to this, ATF imposes no restrictions on what a test program can send to these two channels; in fact, they are encouraged to print as much useful information as possible to aid in the debugging of test failures.

Because we have no control over the two standard streams, the ‘application/X-atf-tcs’ format describes the structure of a third stream, known as the results output, that test programs must generate. (Note that test programs send, by default, the results output to the standard output; use their -r flag to change this whenever you need to parse the data.) This stream is decoupled from the other two and has the following grammar:

    DATA ::= TCS-COUNT TC-STANZA* EOF
    TCS-COUNT ::= 'tcs-count' COLON POSITIVE-NUMBER NEWLINE
    TC-STANZA ::= TC-START TC-END
    TC-START ::= 'tc-start' COLON STRING NEWLINE
    TC-END ::= 'tc-end' COLON STRING COMMA TCR NEWLINE
    TCR ::= 'passed' | ('failed' | 'skipped') COMMA STRING

The meaning of the constructions above is:

TCS-COUNT
    Indicates the number of test cases that will be executed. There will be this exact amount of ‘TC-STANZA’ constructions following it.

TC-START
    Indicates the beginning of a test case. This is accompanied by the test case's name.

TC-END
    Indicates the completion of a test case. This is accompanied by the test case's name, its result and the reason associated with this result (if applicable).

There are multiple reasons behind this design:

•   The reader of this format must be able to show real-time progress to the user as the test cases are processed. Therefore, the ‘TC-START’ construction tells the reader when a test case has started to process data.

•   The reader of this format has to be able to provide useful statistics to the user without having to wait for the end of the file. Hence, the existence of the ‘TCS-COUNT’ construction located at the beginning of the file.

•   Text-based tools have to be able to easily look for the results of a given test case. This is why the ‘TC-END’ construction duplicate the test case name already provided in ‘TC-START’.

An example:

    tcs-count: 2
    tc-start: add
    tc-end: add, passed
    tc-start: subtract
    tc-end: subtract, failed, Calculated an unexpected value

Going back to the standard output and standard error streams, the reader has to be able to match the messages in those two streams to the test cases they belong to. To do this, these two streams must print a magic string that separates the output of test cases from each other, which is enough to synchronize their contents with the results output. This string is ‘__atf_tc_separator__’ and it must printed on a line of its own. The last test case should not be followed by this line because the end of file marker takes its role.

  Format: application/X-atf-tps, version: 2
The ‘application/X-atf-tps’ format multiplexes the standard output, standard error and results output streams from multiple test programs into a single data file. This format is used by atf-run(1) to report the execution of several test programs and is later parsed by atf-report(1) to inform the user of this process. It has the following grammar:

    DATA ::= INFO* TPS-COUNT TP-STANZA* INFO* EOF
    INFO ::= 'info' COLON STRING COMMA STRING NEWLINE
    TPS-COUNT ::= 'tps-count' COLON POSITIVE-NUMBER NEWLINE
    TP-STANZA ::= TP-START TC-STANZA* TC-END
    TP-START ::= 'tp-start' COLON STRING COMMA POSITIVE-NUMBER NEWLINE
    TP-END ::= 'tc-end' COLON STRING (COMMA STRING)?
    TC-STANZA ::= TC-START (TC-SO | TC-SE)* TC-END
    TC-START ::= 'tc-start' COLON STRING NEWLINE
    TC-SO ::= 'tc-so' COLON STRING NEWLINE
    TC-SE ::= 'tc-se' COLON STRING NEWLINE
    TC-END ::= 'tc-end' COLON STRING COMMA TCR NEWLINE
    TCR ::= 'passed' | ('failed' | 'skipped') COMMA STRING

The meaning of the constructions above is:

TPS-COUNT
    Indicates the number of test programs that will be executed. There will be this exact amount of ‘TP-STANZA’ constructions following it.

TP-START
    Indicates the beginning of a test program. This includes the program's name and the amount of test cases that will follow.

TP-END
    Indicates the completion of a test program. This is followed by the program's name and, if the program ended prematurely, an error message indicating the reason of its failure. A successful execution of a test program (regardless of the status of its test cases) must not be accompanied by any reason.

TC-START
    Indicates the beginning of a test case. This is accompanied by the test case's name.

TC-SO
    Contains a text line sent to the standard output stream during the execution of the test case. Leading and trailing space is preserved.

TC-SE
    Contains a text line sent to the standard error stream during the execution of the test case. Leading and trailing space is preserved.

TC-END
    Indicates the completion of a test case. This is accompanied by the test case's name, its result and the reason associated with this result (if applicable).

An example:

    tps-count: 2
    tp-start: calculator, 2
    tc-start: add
    tc-end: add, passed
    tc-start: subtract
    tc-so: 3-2 expected to return 1 but got 0
    tc-end: subtract, failed, Calculated an unexpected value
    tp-end: calculator
    tp-start: files, 1
    tc-start: copy
    tc-se: could not find the cp(1) utility
    tc-end: copy, skipped
    tp-end: files

SEE ALSO
atf(7)