dejagnu.info-2   [plain text]


This is Info file dejagnu.info, produced by Makeinfo version 1.68 from
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START-INFO-DIR-ENTRY
* DejaGnu: (dejagnu).            The GNU testing framework.
END-INFO-DIR-ENTRY

   Copyright (C) 92, 93, 94, 95, 1996 Free Software Foundation, Inc.

   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided also
that the entire resulting derived work is distributed under the terms
of a permission notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions.


File: dejagnu.info,  Node: Names,  Next: Init Module,  Up: Internals

Conventions for using tool names
================================

   DejaGnu uses `$tool', the name of the tool under test, to tie
together the testing configuration in a straightforward but flexible
way. If there is only one testsuite for a particular application, then
`$tool' is optional.

   `$tool' is *not* used to invoke the tool, since sites that run
multiple configurations of a particular tool often call each
configuration by a different name.  `runtest' uses the
configuration-dependent variables captured in `site.exp' to determine
how to call each tool.

   `runtest' uses tool names to find directories containing tests.
`runtest' scans the source directory (specified with `--srcdir') for
all directories whose names start with the tool name. It is a common
practice to put a period after the tool part of the name. For instance,
directories that start with `g++.' contain G++ tests.  To add a new
test, just put it in any directory (create an entirely new directory,
if you wish) whose name follows this convention.

   A test is any file in an appropriately named subdirectory whose name
ends in `.exp' (the conventional way of naming `expect' scripts).
These simple naming conventions make it as simple as possible to
install new tests: all you must do is put the test in the right
directory.

   `runtest' sorts the tests in each subdirectory by name (using the
Tcl `lsort' command) and runs them in the resulting order.


File: dejagnu.info,  Node: Init Module,  Next: DejaGnu Builtins,  Prev: Names,  Up: Internals

Initialization module
=====================

   The initialization module (or "init file") has two purposes: to
provide tool and target dependent procedures, and to start up an
interactive tool to the point where it is ready to operate.  The latter
includes establishing communications with the target.  All the tests for
interactive programs assume that the tool is already running and
communicating.  Initialization modules for non-interactive programs may
only need to supply the support functions.

   Each test suite directory must contain (in its `config'
subdirectory) a separate initialization module for each target.  The
appropriate init file is can be named several ways. The prefered name is
the *os* part of the canonical configuration name with `.exp' as the
suffix. An example would be that for an `m68k-coff' system, the
`target_os' part would be `coff'. The next way is for system where
there are short filenames, or a shortcut is desired to refer to the OS
name for that target. This is uses the value of `$target_abbrev' rather
than the `target_os'.

   The final file looked for is simply `default.exp'. If there is only
one operating system to support, then this file can be used. It's main
purpose is to offer some support for new operating systems, or for
unsupported cross targets. The last file looked for is `unknown.exp'.
This is usually limited to error handling for unsupported targets. It's
whole contents is typically.

     perror "Sorry, there is no support for this target"
     exit 1

   At the beginning of the init file, you must first determine the
proper executable name of the tool to execute, since the actual name of
the tool to be tested my vary from system to system. Here's an example
for the GNU C compiler.

     global AR
     # look for the archiver ar
     if ![info exists AR] {
         set AR [findfile $base_dir/../../binutils/ar $base_dir/../../binutils/ar [tr
     ansform ar]]
         verbose "AR defaulting to $AR" 2
     }
     }
     
     global CFLAGS
     if ![info exists CFLAGS] then {
         set CFLAGS ""
     }

   It is always a good idea to first check the variable, and only set
it if it has not yet been defined.  Often the proper value of `AR' is
set on the command line that invokes `runtest'.

   The `findfile' procedure takes as it's first argument a file name to
look for. The second argument is returned if the file is found, and the
third argument is returned if the file is not found. `base_dir' is set
internally by DejaGnu to the top level directory of the object tree.

   The `transform' procedure takes as its argument the native name of a
tool (such as `gcc' for the compiler), and returns the name as
configured for that tool in the current installation.  (For example, a
cross-compiling version of GNU CC that generates MIPS code may be
installed with a name like `mips-idt-ecoff-gcc'.)

   In a test running native, writing the Tcl code for initialization is
usually quite simple.  For cross configurations, however, more elaborate
instructions are usually needed to describe how to talk to a remote
target.

   Each initialization module defines up to four procedures with
standard names and purposes.  The names of these procedures begin with
`$tool', the string that identifies tests for a particular tool:
`$tool_start', `$tool_load', `$tool_exit', and `$tool_version'.  For
example, the start procedure for GDB is called `gdb_start'.  (Since
start procedures are used differently for batch and interactive tools,
however, `runtest' itself never calls the start procedure.  Init files
for interactive tools are expected to end by running the start
procedure.)

   The initialization module is also a good place to call `load_lib' to
get any collections of utility procedures meant for a family of test
cases, and to set up default values for any additional Tcl variables
needed for a specific set of tests.

   *Note Target dependent procedures: Target Dependent, for full
descriptions of these procedures.


File: dejagnu.info,  Node: DejaGnu Builtins,  Next: Target Dependent,  Prev: Init Module,  Up: Internals

DejaGnu procedures
==================

   DejaGnu provides these Tcl procedures for use in test scripts.  You
can also use any standard `expect' or Tcl function. These procedures
are stored in libraries, which DejaGnu loads at runtime. Here's
explanation of the library procedures that get loaded at runtime. All
other librarys are optional, and need to be loaded by the testsuite.

* Menu:

* framework.exp::               Core Internal Procedures.
* remote.exp::                  Procedures for remote communication.
* utils.exp::                   Utility procedures.
* target.exp::                  Cross target procedures.
* debugger.exp::                Procedures for debugging your Tcl code.


File: dejagnu.info,  Node: framework.exp,  Next: remote.exp,  Up: DejaGnu Builtins

Core Internal Procedures
------------------------

   *Note A POSIX conforming test framework: Posix, for more detailed
explanations of the test outcomes (`FAIL', `PASS', `UNTESTED',
`UNRESOLVED', `UNSUPPORTED').

`perror "STRING NUMBER"'
     Declares a severe error in the testing framework itself.  `perror'
     writes in the log files a message beginning with `ERROR',
     appending the argument STRING. If the optional NUMBER is supplied,
     then this is used to set the internal count of errors to that
     value.

     As a side effect, `perror' also changes the effect of the next
     `pass' or `fail' command: the test outcome becomes `UNRESOLVED',
     since an automatic `PASS' or `FAIL' cannot be trusted after a
     severe error in the test framework.  If the optional numeric value
     is `0', then there are no further side effects to calling this
     function, and the following test outcome doesn't become
     `UNRESOLVED'. This can be used for errors with no known side
     effects.

`warning "STRING NUMBER"'
     Declares detection of a minor error in the test case itself.
     `warning' writes in the log files a message beginning with
     `WARNING', appending the argument STRING.  Use `warning' rather
     than `error' for cases (such as communication failure to be
     followed by a retry) where the test case can recover from the
     error.  If the optional NUMBER is supplied, then this is used to
     set the internal count of warnings to that value.

     As a side effect, `warning_threshold' or more calls to `warning'
     in a single test case also changes the effect of the next `pass'
     or `fail' command: the test outcome becomes `UNRESOLVED' since an
     automatic `PASS' or `FAIL' may not be trustworthy after many
     warnings.  If the optional numeric value is `0', then there are no
     further side effects to calling this function, and the following
     test outcome doesn't become `UNRESOLVED'. This can be used for
     errors with no known side effects.

`note "STRING"'
     Appends an informational message to the log file.  `note' writes
     in the log files a message beginning with `NOTE', appending the
     argument STRING.  Use `note' sparingly.  `verbose' should be used
     for most such messages, but in cases where a message is needed in
     the log file regardless of the verbosity level use `note'.

`pass "STRING"'
     Declares a test to have passed.  `pass' writes in the log files a
     message beginning with `PASS' (or `XPASS', if failure was
     expected), appending the argument STRING.

`fail "STRING"'
     Declares a test to have failed.  `fail' writes in the log files a
     message beginning with `FAIL' (or `XFAIL', if failure was
     expected), appending the argument STRING.

`unresolved "STRING"'
     Declares a test to have an unresolved outcome.  `unresolved' writes
     in the log file a message beginning with `UNRESOLVED', appending
     the argument STRING.  This usually means the test did not execute
     as expected, and a human being must go over results to determine
     if it passed or failed (and to improve the test case).

`untested "STRING"'
     Declares a test was not run.  `untested' writes in the log file a
     message beginning with `UNTESTED', appending the argument STRING.
     For example, you might use this in a dummy test whose only role is
     to record that a test does not yet exist for some feature.

`unsupported "STRING"'
     Declares that a test case depends on some facility that does not
     exist in the testing environment.  `unsupported' writes in the log
     file a message beginning with `UNSUPPORTED', appending the argument
     STRING.

`get_warning_threshold'
     Returns the current value of `warning_threshold'.  The default
     value is 3.

`set_warning_threshold THRESHOLD'
     Sets the value of `warning_threshold'.  A value of `0' disables
     it: calls to `warning' will not turn a `PASS' or `FAIL' into an
     `UNRESOLVED'.

`transform "TOOLNAME"'
     Generates a string for the name of a tool as it was configured and
     installed, given its native name (as the argument TOOLNAME).  This
     makes the assumption that all tools are installed using the same
     naming conventions: it extrapolates from the invocation name for
     `runtest'.  For example, if you call `runtest' as
     `m68k-vxworks-runtest', the result of ` transform "gcc" ' is
     `m68k-vxworks-gcc'.

`ishost "HOST"'
     Tests for a particular *host* environment.  If the currently
     configured host matches the argument string, the result is `1';
     otherwise the result is `0'.  HOST must be a full three-part
     `configure' host name; in particular, you may not use the shorter
     nicknames supported by `configure' (but you can use wildcard
     characters, using shell syntax, to specify sets of names).

`istarget "TARGET"'
     Tests for a particular *target* environment.  If the currently
     configured target matches the argument string, the result is `1';
     otherwise the result is `0'.  TARGET must be a full three-part
     `configure' target name; in particular, you may not use the
     shorter nicknames supported by `configure' (but you can use
     wildcard characters, using shell syntax, to specify sets of
     names). If it is passed a `NULL' string, then it returns the name
     of the build canonical configuration.

`isbuild "HOST"'
     Tests for a particular *build host* environment.  If the currently
     configured host matches the argument string, the result is `1';
     otherwise the result is `0'.  HOST must be a full three-part
     `configure' host name; in particular, you may not use the shorter
     nicknames supported by `configure' (but you can use wildcard
     characters, using shell syntax, to specify sets of names). If it is
     passed a `NULL' string, then it returns the name of the build
     canonical configuration.

     item is3way "HOST" Tests for a canadian cross. This is when the
     tests will be run on a remotly hosted cross compiler. If it is a
     canadian cross, then the result is `1'; otherwise the result is
     `0'.

`isnative'
     Tests whether the current configuration has the same host and
     target.  When it runs in a *native* configuration this procedure
     returns a `1'; otherwise it returns a `0'.

`load_lib "LIBRARY-FILE"'
     Loads the file LIBRARY-FILE by searching a fixed path built into
     `runtest'.  If DejaGnu has been installed, it looks in a path
     starting with the installed library directory.  If you are running
     DejaGnu directly from a source directory, without first running
     `make install', this path defaults to the current directory.  In
     either case, it then looks in the current directory for a directory
     called `lib'.  If there are duplicate definitions, the last one
     loaded takes precedence over the earlier ones.

`setup_xfail "CONFIG  [BUGID]"'
     Declares that the test is expected to fail on a particular set of
     configurations.  The CONFIG argument must be a list of full
     three-part `configure' target name; in particular, you may not use
     the shorter nicknames supported by `configure' (but you can use the
     common shell wildcard characters to specify sets of names).  The
     BUGID argument is optional, and used only in the logging file
     output; use it as a link to a bug-tracking system such as GNATS
     (*note Overview: (gnats.info)Overview.).

     Once you use `setup_xfail', the `fail' and `pass' procedures
     produce the messages `XFAIL' and `XPASS' respectively, allowing
     you to distinguish expected failures (and unexpected success!)
     from other test outcomes.

     *Warning:* you must clear the expected failure after using
     `setup_xfail' in a test case.  Any call to `pass' or `fail' clears
     the expected failure implicitly; if the test has some other
     outcome, e.g. an error, you can call `clear_xfail' to clear the
     expected failure explicitly.  Otherwise, the expected-failure
     declaration applies to whatever test runs next, leading to
     surprising results.

`clear_xfail CONFIG'
     Cancel an expected failure (previously declared with `setup_xfail')
     for a particular set of configurations.  The CONFIG argument is a
     list of configuration target names.  It is only necessary to call
     `clear_xfail' if a test case ends without calling either `pass' or
     `fail', after calling `setup_xfail'.

`verbose [-log] [-n] [--] "STRING" NUMBER'
     Test cases can use this function to issue helpful messages
     depending on the number of `--verbose' options on the `runtest'
     command line.  It prints STRING if the value of the variable
     `verbose' is higher than or equal to the optional NUMBER. The
     default value for NUMBER is 1.  Use the optional `-log' argument
     to cause STRING to always be added to the log file, even if it
     won't be printed.  Use the optional `-n' argument to print STRING
     without a trailing newline.  Use the optional `--' argument if
     STRING begins with "-".


File: dejagnu.info,  Node: remote.exp,  Next: utils.exp,  Prev: framework.exp,  Up: DejaGnu Builtins

Remote Communication Procedures
-------------------------------

`lib/remote.exp' defines these functions, for establishing and managing
communications:

   *Procedures to establish a connection:* Each of these procedures
tries to establish the connection up to three times before returning.
Warnings (if retries will continue) or errors (if the attempt is
abandoned) report on communication failures.  The result for any of
these procedures is either `-1', when the connection cannot be
established, or the spawn ID returned by the `expect' command `spawn'.

   It use the value of the `connect' field in the `target_info' array
(was `connectmode' as the type of connection to make. Current supported
connection types are tip, kermit, telnet, rsh, rlogin, and netdata. If
the `--reboot' option was used on the runtest command line, then the
target is rebooted before the connection is made.

`remote_open TYPE'
     *Remote Connection Procedure.* This is passed *host* or *target*.
     Host or target refers to whether it is a connection to a remote
     target, or a remote host. This opens the connection to the desired
     target or host using the default values in the configuration
     system. It returns that `spawn_id' of the process that manages the
     connection. This value can be used in `expect' or `exp_send'
     statements, or passed to other procedures that need the connection
     process's id. This also sets the `fileid' field in the
     `target_info' array.

`remote_close SHELLID'
     *shellid* is value returned by a call to `remote_open'. This
     closes the connection to the target so resources can be used by
     others. This parameter can be left off if the `fileid' field in the
     `target_info' array is set.

`telnet HOSTNAME PORT'
`rlogin HOSTNAME'
`rsh HOSTNAME'
     *IP network procedures.* HOSTNAME refers to the IP address or name
     (for example, an entry in `/etc/hosts') for this target.  The
     procedure names reflect the Unix utility used to establish a
     connection. The optional PORT is used to specify the IP port
     number. The value of the `netport' field in the `target_info'
     array is used. (was `$netport') This value has two parts, the
     hostname and the port number, seperated by a *:*. If `host' or
     `target' is used in the `hostname' field, than the config array is
     used for all information.

`tip PORT'
     *Serial line procedure.* Connect using the Unix utility `tip'.
     PORT must be a name from the `tip' configuration file
     `/etc/remote'.  Often, this is called `hardwire', or something
     like `ttya'. This file holds all the configuration data for the
     serial port. The value of the `serial' field in the `target_info'
     array is used. (was `$serialport') If `host' or `target' is used
     in the `port' field, than the config array is used for all
     information.

`kermit PORT BPS'
     *Serial line procedure.*  Connect using the program `kermit'.
     PORT is the device name, e.g. `/dev/ttyb'.  BPS is the line speed
     to use (in bits per second) for the connection. The value of the
     `serial' field in the `target_info' array is used. (was
     `$serialport') If `host' or `target' is used in the `port' field,
     than the config array is used for all information.

*Procedures to manage a connection:*

`tip_download SPAWNID FILE'
     Download `FILE' to the process SPAWNID (the value returned when
     the connection was established), using the `~put' command under
     `tip'.  Most often used for single board computers that require
     downloading programs in ASCII S-records.  Returns `1' if an error
     occurs, `0' otherwise.

`exit_remote_shell SPAWNID'
     Exits a remote process started by any of the connection procedures.
     SPAWNID is the result of the connection procedure that started the
     remote process.

`download FILE [ SPAWNID ]'
     After you establish a connection to a target, you can download
     programs using this command.  `download' reads in FILE (object
     code in S-record format) and writes it to the device controlling
     this SPAWNID.  (From the point of view of the target, the S-record
     file comes in via standard input.)

     If you have more than one target active, you can use the optional
     argument SPAWNID to specify an alternative target (the default is
     the most recently established SPAWNID.)


File: dejagnu.info,  Node: utils.exp,  Next: target.exp,  Prev: remote.exp,  Up: DejaGnu Builtins

Utility Procedures
------------------

`lib/utils.exp' defines these utility procedures:

`getdirs DIR'
`getdirs DIR PATTERN'
     Returns a list of all the directories in the single directory DIR
     that match PATTERN.  If you do not specify PATTERN, `getdirs'
     assumes `*'.  You may use the common shell wildcard characters in
     PATTERN. If no directories match the pattern, then a `NULL' string
     is returned.

`find DIR PATTERN'
     Search for files whose names match PATTERN (using shell wildcard
     characters for filename expansion).  Search subdirectories
     recursively, starting at DIR.  The result is the list of files
     whose names match; if no files match, the result is empty.
     Filenames in the result include all intervening subdirectory
     names. If no files match the pattern, then a `NULL' string is
     returned.

`which BINARY'
     Searches the execution path for an executable file BINARY, like
     the the BSD `which' utility.  This procedure uses the shell
     environment variable `PATH'. It returns `0' if the binary is not
     in the path, or if there is no `PATH' environment variable. If
     BINARY is in the path, it returns the full path to BINARY.

`grep FILENAME REGEXP'

`grep FILENAME REGEXP line'
     Search the file called FILENAME (a fully specified path) for lines
     that contain a match for regular expression REGEXP.  The result is
     a list of all the lines that match.  If no lines match, the result
     is an empty string.  Specify REGEXP using the standard regular
     expression style used by the Unix utility program `grep'.

     Use the optional third argument `line' to start lines in the result
     with the line number in FILENAME.  (This argument is simply an
     option flag; type it just as shown--`line'.)

`diff FILENAME FILENAME'
     Compares the two files and returns a 1 if they match, or a 0 if
     they don't. If `verbose' is set, then it'll print the differences
     to the screen.

`slay NAME'
     This look in the process tabel for NAME and send it a unix
     `SIGINT', killing the process.

`absolute PATH'
     This procedure takes the relative PATH, and converts it to an
     absolute path.

`psource FILENAME'
     This sources the file FILENAME, and traps all errors. It also
     ignores all extraneous output. If there was an error it returns a
     1, otherwise it returns a 0.

`prune LIST PATTERN'
     Remove elements of the Tcl list LIST.  Elements are fields
     delimited by spaces.  The result is a copy of LIST, without any
     elements that match PATTERN.  You can use the common shell
     wildcard characters to specify PATTERN.

`setenv VAR VAL'
     Sets the variable VAR to the value VAL.

`unsetenv VAR'
     Unsets the environment variable VAR

`getenv VAR'
     returns the value of VAR in the environment if it exists,
     otherwise it returns `NULL'.

`runtest_file_p RUNTESTS TESTCASE'
     Search RUNTESTS for TESTCASE and return 1 if found, 0 if not.
     RUNTESTS is a list of two elements.  The first is the pathname of
     the testsuite expect script running.  The second is a copy of what
     was on the right side of the `=' if `foo.exp="..."' was specified,
     or an empty string if no such argument is present.  This is used
     by tools like compilers where each testcase is a file.

`prune_system_crud SYSTEM TEXT'
     For system SYSTEM, delete text the host or target operating system
     might issue that will interfere with pattern matching of program
     output in TEXT.  An example is the message that is printed if a
     shared library is out of date.


File: dejagnu.info,  Node: target.exp,  Next: debugger.exp,  Prev: utils.exp,  Up: DejaGnu Builtins

Cross target procedure
----------------------

`lib/target.exp' defines these utility procedures:

`push_target *name*'
     This makes the target named *name* be the current target
     connection. The value of *name* is an index into the `target_info'
     array and is set in the global config file.

`pop_target'
     This unsets the current target connection.

`list_targets'
     This lists all the supported targets for this architecture.

`push_host *name*'
     This makes the host named *name* be the current remote host
     connection. The value of *name* is an index into the `target_info'
     array and is set in the global config file.

`pop_host'
     This unsets the current host connection.

     This invokes the compiler as set by `CC' to compile the file
     *file*. The default options for many cross compilation targets are
     *guessed* by DejaGnu, and these options can be added to by passing
     in more parameters as arguments to `compile'. Optionally, this will
     also use the value of the `cflags' field in the target config
     array. If the host is not the same as the build machines, then then
     compiler is run on the remote host using `execute_anywhere'.

     This produces an archive file. Any parameters passed to `archive'
     are used in addition to the default flags. Optionally, this will
     also use the value of the `arflags' field in the target config
     array. If the host is not the same as the build machines, then then
     archiver is run on the remote host using `execute_anywhere'.

     This generates an index for the archive file for systems that
     aren't POSIX yet. Any parameters passed to `ranlib' are used in
     for the flags.

`execute_anywhere *cmdline*'
     This executes the *cmdline* on the proper host. This should be used
     as a replacement for the Tcl command `exec' as this version
     utilizes the target config info to execute this command on the
     build machine or a remote host. All config information for the
     remote host must be setup to have this command work. If this is a
     canadian cross, (where we test a cross compiler that runs on a
     different host then where DejaGnu is running) then a connection is
     made to the remote host and the command is executed there. It
     returns either *REMOTERROR* (for an error) or the output produced
     when the command was executed. This is used for running the tool
     to be tested, not a test case.


File: dejagnu.info,  Node: debugger.exp,  Prev: target.exp,  Up: DejaGnu Builtins

Debugging Procedures
--------------------

   `lib/debugger.exp' defines these utility procedures:

`dumpvars *expr*'
     This takes a csh style regular expression (glob rules) and prints
     the values of the global variable names that match.  It is
     abbreviated as `dv'

`dumplocals *expr*'
     This takes a csh style regular expression (glob rules) and prints
     the values of the local variable names that match. It is
     abbreviated as `dl'.

`dumprocs *expr*'
     This takes a csh style regular expression (glob rules) and prints
     the body of all procs that match. It is abbreviated as `dp'

`dumpwatch *expr*'
     This takes a csh style regular expression (glob rules) and prints
     all the watchpoints. It is abbreviated as `dw'.

`watchunset *var*'
     This breaks program execution when the variable *var* is unset. It
     is abbreviated as `wu'.

`watchwrite *var*'
     This breaks program execution when the variable *var* is written.
     It is abbreviated as `ww'.

`watchread *var*'
     This breaks program execution when the variable *var* is read. It
     is abbreviated as `wr'.

`watchdel *watch*'
     This deletes a the watchpoint for *watch*. It is abbreviated as
     `wd'.

`print *var*'
     This prints the value of the variable *var*. It is abbreviated as
     `p'.

`quit'
     This makes runtest exit. It is abbreviated as `q'.

`bt'
     This prints a backtrace of the executed Tcl commands.


File: dejagnu.info,  Node: Target Dependent,  Next: Cross Targets,  Prev: DejaGnu Builtins,  Up: Internals

Target dependent procedures
===========================

   Each combination of target and tool requires some target-dependent
procedures.  The names of these procedures have a common form: the tool
name, followed by an underbar `_', and finally a suffix describing the
procedure's purpose.  For example, a procedure to extract the version
from GDB is called `gdb_version'.  *Note Initialization Module: Init
Module, for a discussion of how DejaGnu arranges to find the right
procedures for each target.

   `runtest' itself calls only two of these procedures, `TOOL_exit' and
`TOOL_version'; these procedures use no arguments.

   The other two procedures, `TOOL_start' and `TOOL_load', are only
called by the test suites themselves (or by testsuite-specific
initialization code); they may take arguments or not, depending on the
conventions used within each test suite.

`TOOL_start'
     Starts a particular tool.  For an interactive tool, `TOOL_start'
     starts and initializes the tool, leaving the tool up and running
     for the test cases; an example is `gdb_start', the start function
     for GDB.  For a batch oriented tool, `TOOL_start' is optional; the
     recommended convention is to let `TOOL_start' run the tool,
     leaving the output in a variable called `comp_output'.  Test
     scripts can then analyze `$comp_output' to determine the test
     results.  An example of this second kind of start function is
     `gcc_start', the start function for GCC.

     `runtest' itself *does not call* `TOOL_start'.  The initialization
     module `TOOL_init.exp' must call `TOOL_start' for interactive
     tools; for batch-oriented tools, each individual test script calls
     `TOOL_start' (or makes other arrangements to run the tool).

`TOOL_load'
     Loads something into a tool. For an interactive tool, this
     conditions the tool for a particular test case; for example,
     `gdb_load' loads a new executable file into the debugger. For
     batch oriented tools, `TOOL_load' may do nothing--though, for
     example, the GCC support uses `gcc_load' to load and run a binary
     on the target environment.  Conventionally, `TOOL_load' leaves the
     output of any program it runs in a variable called `exec_output'.
     Writing `TOOL_load' can be the most complex part of extending
     DejaGnu to a new tool or a new target, if it requires much
     communication coding or file downloading.

     Test scripts call `TOOL_load'.

`TOOL_exit'
     Cleans up (if necessary) before `runtest' exits. For interactive
     tools, this usually ends the interactive session.  You can also use
     `TOOL_exit' to remove any temporary files left over from the tests.

     `runtest' calls `TOOL_exit'.

`TOOL_version'
     Prints the version label and number for TOOL.  This is called by
     the DejaGnu procedure that prints the final summary report.  The
     output should consist of the full path name used for the tested
     tool, and its version number.

     `runtest' calls `TOOL_version'.

   The usual convention for return codes from any of these procedures
(although it is not required by `runtest') is to return `0' if the
procedure succeeded, `1' if it failed, and `-1' if there was a
communication error.


File: dejagnu.info,  Node: Cross Targets,  Next: Input Files,  Prev: Target Dependent,  Up: Internals

Remote targets supported
========================

   The DejaGnu distribution includes support for the following remote
targets.  You can set the target name and the connect mode in the
`site.exp' file (using the Tcl variables `targetname' and
`connectmode', respectively), or on the `runtest' command line (using
`--name' and `--connect').

*AMD 29000, with UDI protocol*
     Configure DejaGnu for target `a29k-amd-udi'.  (Cygnus `configure'
     also recognizes the abbreviation `udi29k'.)  Then, to run tests,
     use the `runtest' target name to specify whether you want to use a
     simulator, or a particular hardware board.  The particular string
     to use with `--name' will depend on your UDI setup file, `udi_soc'
     (if `udi_soc' is not in your working directory, the environment
     variable `UDICONF' should contain a path to this file).  For
     example, if your UDI setup file includes these lines:

     iss   AF_UNIX  *   isstip -r /home/gnu/29k/src/osboot/sim/osboot
     mon   AF_UNIX  *   montip -t serial -baud 9600 -com /dev/ttyb

* *
     You can use `--name iss' to run tests on the simulator, and
     `--name mon' to run tests on the 29K hardware.  See the
     manufacturer's manuals for more information on UDI and `udi_soc'.

     The default connect protocol is `mondfe' with either back end.
     `mondfe' is the only shell DejaGnu supports for UDI targets.
     `mondfe' is an AMD specific monitor program freely available from
     AMD.

     *Warning:* This target requires GDB version 4.7.2 (or greater).
     Earlier versions of GDB do not fully support the `load' command on
     this target, so DejaGnu has no way to load executable files from
     the debugger.

*Motorola 680x0 boards, a.out or COFF object format*
     Configure DejaGnu for any remote target matching `m68k-*'.

     *Warning:* Most `m68k-*' configurations run all tests only for
     native testing (when the target is the same as the host).  When you
     specify most of these targets for a cross configuration, you will
     only be able to use tests that run completely within the host (for
     example, tests of the binary utilities such as the archiver; or
     compiler tests that only generate code rather than running it).

     To run a.out or COFF binaries on a remote M68K, you must configure
     DejaGnu for a particular target board.  `m68k-abug' is an example.
     (In general for an embedded environment, because it does not have
     absolute addresses, a.out is not a good choice for output format
     in any case; most often S-records or Hex-32 are used instead.)

*Motorola 68K MVME 135 board running ABug boot monitor*
     Configure for `m68k-abug-aout' or `m68k-abug-coff' (as a target).
     This boot monitor can only download S-records; therefore, the
     DejaGnu tests for this environment require a linker command script
     to convert either output format to S-records, setting the default
     addresses for `.text', `.bss', and `.data'.

     With this configuration, the default for `--connect' is `tip'.
     `tip' is the only communications protocol supported for connecting
     to `m68k-abug-*' targets.  `tip' uses an ASCII downloader (the
     `~put' command) to load S-records into the target board.  The
     `--name' string must be a machine name that `tip' understands (for
     example, on some `tip' implementations it must be an entry from
     the initialization file for `tip'; this file is sometimes called
     `/etc/remote').

     See your system documentation for information on how to create new
     entries in `/etc/remote'.  (Some UNIX systems are distributed with
     at least one default entry with a name resembling `hardwire'; if
     your system has one, you can edit it, or make a modified copy with
     a new name.)  When you have a working `/etc/remote' entry
     ABUGTARGET, you should be able to type `tip ABUGTARGET', and get
     the prompt `135ABUG>' from the board.  Use the same ABUGTARGET
     string with `runtest --name'.

*Motorola IDP board running the rom68k boot monitor*
     This is the same in functionality as the MVME board running the
     `BUG' boot monitor. Only the monitor commands and the addresses are
     different.

*VxWorks (Motorola 68K or Intel 960)*
     Configure DejaGnu for either `m68k-wrs-vxworks' (abbreviated
     `vxworks68') or `i960-wrs-vxworks' (abbreviated `vxworks960').
     Since both targets support IP addressing, specify the network
     address (for example, a host name from `/etc/hosts') with `--name'.

     The default connect protocol is `rlogin', but you can use any of
     `--connect rlogin', `--connect telnet', or `--connect rsh'.

     Test scripts need no special code to load programs into these
     targets; since VxWorks supports NFS, all you must do is ensure
     test programs are on an exported filesystem.

     When you compile for VxWorks, use the linker `-r' option to make
     the linker output relocatable--at least if you want to use library
     routines. Many standard C routines are included in VxWorks; often
     no additional libraries are needed.  See your VxWorks system
     documentation for additional details.


File: dejagnu.info,  Node: Input Files,  Next: Output Files,  Prev: Cross Targets,  Up: Internals

The files DejaGnu reads
=======================

   The `runtest' program used to invoke DejaGnu is a short shell script
generated by `make' during the configuration process.  Its main task is
to read the main test framework driver, `runtest.exp'.

   `runtest.exp', in turn, reads `expect' code from certain other
files, in this order:

  1. Each of the `site.exp' local definition files available.  *Note
     Setting `runtest' defaults: Customizing, for details.

  2. `lib/utils.exp', a collection of utility procedures.  *Note
     DejaGnu Builtins: DejaGnu Builtins, for descriptions of these
     procedures.

  3. `lib/framework.exp', a file of subroutines meant for `runtest'
     itself rather than for general-purpose use in both `runtest' and
     test suites.

  4. `debugger.exp', Don Libes' Tcl Debugger.  (See `A Debugger for Tcl
     Applications' by Don Libes. This paper is distributed with
     `expect' in PostScript form as the file `expect/tcl-debug.ps'.)

  5. `lib/remote.exp', a collection of subroutines meant for connecting
     to remote machines.

  6. `lib/target.exp', a collection of subroutines used for the
     configuration systems in DejaGnu. These procedures typically
     manipulate or utilize the configuration system.

  7. An initialization file `TOOL_init.exp'.  *Note Initialization
     module: Init Module, for more discussion of init files.


File: dejagnu.info,  Node: Output Files,  Prev: Input Files,  Up: Internals

The files DejaGnu writes
========================

   `runtest' always writes two kinds of output files: summary logs and
detailed logs.  The contents of both of these are determined by your
tests.

   For troubleshooting, a third kind of output file is useful: use
`--debug' to request an output file showing details of what `expect' is
doing internally.

* Menu:

* Summary::             Files that summarize tests
* Detail::              Files that contain complete test results
* Debug::               Logging expect internal actions


File: dejagnu.info,  Node: Summary,  Next: Detail,  Up: Output Files

Summary log
-----------

   `runtest' always produces a summary output file `TOOL.sum'.  This
summary shows the names of all test files run; for each test file, one
line of output from each `pass' command (showing status `PASS' or
`XPASS') or `fail' command (status `FAIL' or `XFAIL'); trailing summary
statistics that count passing and failing tests (expected and
unexpected); and the full pathname and version number of the tool
tested.  (All possible outcomes, and all errors, are always reflected in
the summary output file, regardless of whether or not you specify
`--all'.)

   If any of your tests use the procedures `unresolved', `unsupported',
or `untested', the summary output also tabulates the corresponding
outcomes.

   For example, after `runtest --tool binutils', look for a summary log
in `binutils.sum'.  Normally, `runtest' writes this file in your
current working directory; use the `--outdir' option to select a
different directory.

Here is a short sample summary log:

     Test Run By rob on Mon May 25 21:40:57 PDT 1992
                     === gdb tests ===
     Running ./gdb.t00/echo.exp ...
     PASS:   Echo test
     Running ./gdb.all/help.exp ...
     PASS:   help add-symbol-file
     PASS:   help aliases
     PASS:   help breakpoint "bre" abbreviation
     FAIL:   help run "r" abbreviation
     Running ./gdb.t10/crossload.exp ...
     PASS:   m68k-elf (elf-big) explicit format; loaded
     XFAIL:  mips-ecoff (ecoff-bigmips) "ptype v_signed_char" signed
     C types
                     === gdb Summary ===
     # of expected passes 5
     # of expected failures 1
     # of unexpected failures 1
     /usr/latest/bin/gdb version 4.6.5 -q


File: dejagnu.info,  Node: Detail,  Next: Debug,  Prev: Summary,  Up: Output Files

Detailed log
------------

   `runtest' also saves a detailed log file `TOOL.log', showing any
output generated by tests as well as the summary output.  For example,
after `runtest --tool binutils', look for a detailed log in
`binutils.log'.  Normally, `runtest' writes this file in your current
working directory; use the `--outdir' option to select a different
directory.

Here is a brief example showing a detailed log for G++ tests:

     Test Run By rob on Mon May 25 21:40:43 PDT 1992
     
                     === g++ tests ===
     
     --- Running ./g++.other/t01-1.exp ---
             PASS:   operate delete
     
     --- Running ./g++.other/t01-2.exp ---
             FAIL:   i960 bug EOF
     p0000646.C: In function `int  warn_return_1 ()':
     p0000646.C:109: warning: control reaches end of non-void function
     p0000646.C: In function `int  warn_return_arg (int)':
     p0000646.C:117: warning: control reaches end of non-void function
     p0000646.C: In function `int  warn_return_sum (int, int)':
     p0000646.C:125: warning: control reaches end of non-void function
     p0000646.C: In function `struct foo warn_return_foo ()':
     p0000646.C:132: warning: control reaches end of non-void function
     
     --- Running ./g++.other/t01-4.exp ---
             FAIL:   abort
     900403_04.C:8: zero width for bit-field `foo'
     --- Running ./g++.other/t01-3.exp ---
             FAIL:   segment violation
     900519_12.C:9: parse error before `;'
     900519_12.C:12: Segmentation violation
     /usr/latest/bin/gcc: Internal compiler error: program cc1plus got
     fatal signal
     
                     === g++ Summary ===
     
     # of expected passes 1
     # of expected failures 3
     /usr/ps/bin/g++ version cygnus-2.0.1


File: dejagnu.info,  Node: Debug,  Prev: Detail,  Up: Output Files

Logging `expect' internal actions
---------------------------------

   With the `--debug' option, you can request a log file showing the
output from `expect' itself, running in debugging mode. This file
(`dbg.log', in the directory where you start `runtest') shows each
pattern `expect' considers in analyzing test output.

   This file reflects each `send' command, showing the string sent as
input to the tool under test; and each `expect' command, showing each
pattern it compares with the tool output.

   The log messages for `expect' begin with a message of the form

     expect: does {TOOL OUTPUT} (spawn_id N) match pattern
     {EXPECTED PATTERN}?

For every unsuccessful match, `expect' issues a `no' after this
message; if other patterns are specified for the same `expect' command,
they are reflected also, but without the first part of the message
(`expect...match pattern').

   When `expect' finds a match, the log for the successful match ends
with `yes', followed by a record of the `expect' variables set to
describe a successful match.  Here is an excerpt from the debugging log
for a GDB test:

     send: sent {break gdbme.c:34\n} to spawn id 6
     expect: does {} (spawn_id 6) match pattern {Breakpoint.*at.* file
      gdbme.c, line 34.*\(gdb\) $}? no
     {.*\(gdb\) $}? no
     expect: does {} (spawn_id 0) match pattern {<return>}? no
     {\(y or n\) }? no
     {buffer_full}? no
     {virtual}? no
     {memory}? no
     {exhausted}? no
     {Undefined}? no
     {command}? no
     break gdbme.c:34
     Breakpoint 8 at 0x23d8: file gdbme.c, line 34.
     (gdb) expect: does {break gdbme.c:34\r\nBreakpoint 8 at 0x23d8:
     file gdbme.c, line 34.\r\n(gdb) } (spawn_id 6) match pattern
     {Breakpoint.*at.* file gdbme.c, line 34.*\(gdb\) $}? yes
     expect: set expect_out(0,start) {18}
     expect: set expect_out(0,end) {71}
     expect: set expect_out(0,string) {Breakpoint 8 at 0x23d8: file
     gdbme.c, line 34.\r\n(gdb) }
     expect: set expect_out(spawn_id) {6}
     expect: set expect_out(buffer) {break gdbme.c:34\r\nBreakpoint 8
     at 0x23d8: file gdbme.c, line 34.\r\n(gdb) }
             PASS:   70      0       breakpoint line number in file

This example exhibits three properties of `expect' and DejaGnu that
might be surprising at first glance:

   * Empty output for the first attempted match.  The first set of
     attempted matches shown ran against the output `{}'--that is, no
     output.  `expect' begins attempting to match the patterns supplied
     immediately; often, the first pass is against incomplete output (or
     completely before all output, as in this case).

   * Interspersed tool output.  The beginning of the log entry for the
     second attempted match may be hard to spot: this is because the
     prompt `(gdb) ' appears on the same line, just before the `expect:'
     that marks the beginning of the log entry.

   * Fail-safe patterns.  Many of the patterns tested are fail-safe
     patterns provided by GDB testing utilities, to reduce possible
     indeterminacy.  It is useful to anticipate potential variations
     caused by extreme system conditions (GDB might issue the message
     `virtual memory exhausted' in rare circumstances), or by changes in
     the tested program (`Undefined command' is the likeliest outcome if
     the name of a tested command changes).

     The pattern `{<return>}' is a particularly interesting fail-safe
     to notice; it checks for an unexpected <RET> prompt.  This may
     happen, for example, if the tested tool can filter output through a
     pager.

     These fail-safe patterns (like the debugging log itself) are
     primarily useful while developing test scripts.  Use the `error'
     procedure to make the actions for fail-safe patterns produce
     messages starting with `ERROR' on the `runtest' standard output,
     and in the detailed log file.


File: dejagnu.info,  Node: Tests,  Next: Extending,  Prev: Internals,  Up: Top

How To Write a Test Case
************************

* Menu:

* Writing::                     Writing a test case
* Debugging::                   Debugging a test case
* Adding::                      Adding a test case to a test suite
* Hints::                       Hints on writing a test case
* Variables::                   Special variables used by test cases


File: dejagnu.info,  Node: Writing,  Next: Debugging,  Up: Tests

Writing a test case
===================

   The easiest way to prepare a new test case is to base it on an
existing one for a similar situation.  There are two major categories
of tests: batch or interactive.  Batch oriented tests are usually
easier to write.

   The GCC tests are a good example of batch oriented tests.  All GCC
tests consist primarily of a call to a single common procedure, since
all the tests either have no output, or only have a few warning
messages when successfully compiled.  Any non-warning output is a test
failure.  All the C code needed is kept in the test directory.  The test
driver, written in `expect', need only get a listing of all the C files
in the directory, and compile them all using a generic procedure.  This
procedure and a few others supporting for these tests are kept in the
library module `lib/c-torture.exp' in the GCC test suite.  Most tests
of this kind use very few `expect' features, and are coded almost
purely in Tcl.

Writing the complete suite of C tests, then, consisted of these steps:

  1. Copying all the C code into the test directory.  These tests were
     based on the C-torture test created by Torbjorn Granlund (on
     behalf of the Free Software Foundation) for GCC development.

  2. Writing (and debugging) the generic `expect' procedures for
     compilation.

  3. Writing the simple test driver: its main task is to search the
     directory (using the Tcl procedure `glob' for filename expansion
     with wildcards) and call a Tcl procedure with each filename.  It
     also checks for a few errors from the testing procedure.

   Testing interactive programs is intrinsically more complex.  Tests
for most interactive programs require some trial and error before they
are complete.

   However, some interactive programs can be tested in a simple fashion
reminiscent of batch tests.  For example, prior to the creation of
DejaGnu, the GDB distribution already included a wide-ranging testing
procedure.  This procedure was very robust, and had already undergone
much more debugging and error checking than many recent DejaGnu test
cases.  Accordingly, the best approach was simply to encapsulate the
existing GDB tests, for reporting purposes.  Thereafter, new GDB tests
built up a family of `expect' procedures specialized for GDB testing.

   `gdb.t10/crossload.exp' is a good example of an interactive test.