NAME
atf-c-api,
ATF_CHECK,
ATF_CHECK_MSG,
ATF_CHECK_EQ,
ATF_CHECK_EQ_MSG,
ATF_CHECK_MATCH,
ATF_CHECK_MATCH_MSG,
ATF_CHECK_STREQ,
ATF_CHECK_STREQ_MSG,
ATF_CHECK_ERRNO,
ATF_REQUIRE,
ATF_REQUIRE_MSG,
ATF_REQUIRE_EQ,
ATF_REQUIRE_EQ_MSG,
ATF_REQUIRE_MATCH,
ATF_REQUIRE_MATCH_MSG,
ATF_REQUIRE_STREQ,
ATF_REQUIRE_STREQ_MSG,
ATF_REQUIRE_ERRNO,
ATF_TC,
ATF_TC_BODY,
ATF_TC_BODY_NAME,
ATF_TC_CLEANUP,
ATF_TC_CLEANUP_NAME,
ATF_TC_HEAD,
ATF_TC_HEAD_NAME,
ATF_TC_NAME,
ATF_TC_WITH_CLEANUP,
ATF_TC_WITHOUT_HEAD,
ATF_TP_ADD_TC,
ATF_TP_ADD_TCS,
atf_tc_get_config_var,
atf_tc_get_config_var_wd,
atf_tc_get_config_var_as_bool,
atf_tc_get_config_var_as_bool_wd,
atf_tc_get_config_var_as_long,
atf_tc_get_config_var_as_long_wd,
atf_no_error,
atf_tc_expect_death,
atf_tc_expect_exit,
atf_tc_expect_fail,
atf_tc_expect_pass,
atf_tc_expect_signal,
atf_tc_expect_timeout,
atf_tc_fail,
atf_tc_fail_nonfatal,
atf_tc_pass,
atf_tc_skip,
atf_utils_cat_file,
atf_utils_compare_file,
atf_utils_copy_file,
atf_utils_create_file,
atf_utils_file_exists,
atf_utils_fork,
atf_utils_free_charpp,
atf_utils_grep_file,
atf_utils_grep_string,
atf_utils_readline,
atf_utils_redirect,
atf_utils_wait —
C API to write ATF-based test programs
SYNOPSIS
#include <atf-c.h>
ATF_CHECK(
expression);
ATF_CHECK_MSG(
expression,
fail_msg_fmt,
...);
ATF_CHECK_EQ(
expression_1,
expression_2);
ATF_CHECK_EQ_MSG(
expression_1,
expression_2,
fail_msg_fmt,
...);
ATF_CHECK_MATCH(
regexp,
string);
ATF_CHECK_MATCH_MSG(
regexp,
string,
fail_msg_fmt,
...);
ATF_CHECK_STREQ(
string_1,
string_2);
ATF_CHECK_STREQ_MSG(
string_1,
string_2,
fail_msg_fmt,
...);
ATF_CHECK_ERRNO(
exp_errno,
bool_expression);
ATF_REQUIRE(
expression);
ATF_REQUIRE_MSG(
expression,
fail_msg_fmt,
...);
ATF_REQUIRE_EQ(
expression_1,
expression_2);
ATF_REQUIRE_EQ_MSG(
expression_1,
expression_2,
fail_msg_fmt,
...);
ATF_REQUIRE_MATCH(
regexp,
string);
ATF_REQUIRE_MATCH_MSG(
regexp,
string,
fail_msg_fmt,
...);
ATF_REQUIRE_STREQ(
string_1,
string_2);
ATF_REQUIRE_STREQ_MSG(
string_1,
string_2,
fail_msg_fmt,
...);
ATF_REQUIRE_ERRNO(
exp_errno,
bool_expression);
ATF_TC(
name);
ATF_TC_BODY(
name,
tc);
ATF_TC_BODY_NAME(
name);
ATF_TC_CLEANUP(
name,
tc);
ATF_TC_CLEANUP_NAME(
name);
ATF_TC_HEAD(
name,
tc);
ATF_TC_HEAD_NAME(
name);
ATF_TC_NAME(
name);
ATF_TC_WITH_CLEANUP(
name);
ATF_TC_WITHOUT_HEAD(
name);
ATF_TP_ADD_TC(
tp_name,
tc_name);
ATF_TP_ADD_TCS(
tp_name);
atf_tc_get_config_var(
tc,
varname);
atf_tc_get_config_var_wd(
tc,
variable_name,
default_value);
atf_tc_get_config_var_as_bool(
tc,
variable_name);
atf_tc_get_config_var_as_bool_wd(
tc,
variable_name,
default_value);
atf_tc_get_config_var_as_long(
tc,
variable_name);
atf_tc_get_config_var_as_long_wd(
tc,
variable_name,
default_value);
atf_no_error();
atf_tc_expect_death(
reason,
...);
atf_tc_expect_exit(
exitcode,
reason,
...);
atf_tc_expect_fail(
reason,
...);
atf_tc_expect_pass();
atf_tc_expect_signal(
signo,
reason,
...);
atf_tc_expect_timeout(
reason,
...);
atf_tc_fail(
reason);
atf_tc_fail_nonfatal(
reason);
atf_tc_pass();
atf_tc_skip(
reason);
void
atf_utils_cat_file(
const char *file,
const char *prefix);
bool
atf_utils_compare_file(
const char *file,
const char *contents);
void
atf_utils_copy_file(
const char *source,
const char *destination);
void
atf_utils_create_file(
const char *file,
const char *contents,
...);
void
atf_utils_file_exists(
const char *file);
pid_t
atf_utils_fork(
void);
void
atf_utils_free_charpp(
char **argv);
bool
atf_utils_grep_file(
const char *regexp,
const char *file,
...);
bool
atf_utils_grep_string(
const char
*regexp,
const char *str,
...);
char *
atf_utils_readline(
int fd);
void
atf_utils_redirect(
const int fd,
const char *file);
void
atf_utils_wait(
const pid_t pid,
const int expected_exit_status,
const
char *expected_stdout,
const char
*expected_stderr);
DESCRIPTION
ATF provides a C programming interface to implement test programs. C-based test
programs follow this template:
... C-specific includes go here ...
#include <atf-c.h>
ATF_TC(tc1);
ATF_TC_HEAD(tc1, tc)
{
... first test case's header ...
}
ATF_TC_BODY(tc1, tc)
{
... first test case's body ...
}
ATF_TC_WITH_CLEANUP(tc2);
ATF_TC_HEAD(tc2, tc)
{
... second test case's header ...
}
ATF_TC_BODY(tc2, tc)
{
... second test case's body ...
}
ATF_TC_CLEANUP(tc2, tc)
{
... second test case's cleanup ...
}
ATF_TC_WITHOUT_HEAD(tc3);
ATF_TC_BODY(tc3, tc)
{
... third test case's body ...
}
... additional test cases ...
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tcs, tc1);
ATF_TP_ADD_TC(tcs, tc2);
ATF_TP_ADD_TC(tcs, tc3);
... add additional test cases ...
return atf_no_error();
}
Definition of test cases
Test cases have an identifier and are composed of three different parts: the
header, the body and an optional cleanup routine, all of which are described
in
atf-test-case(4). To
define test cases, one can use the
ATF_TC(),
ATF_TC_WITH_CLEANUP() or the
ATF_TC_WITHOUT_HEAD() macros, which take a single parameter
specifiying the test case's name.
ATF_TC(), requires to
define a head and a body for the test case,
ATF_TC_WITH_CLEANUP() requires to define a head, a body and
a cleanup for the test case and
ATF_TC_WITHOUT_HEAD()
requires only a body for the test case. It is important to note that these
do not set the test case up for execution when the program
is run. In order to do so, a later registration is needed with the
ATF_TP_ADD_TC() macro detailed in
Program initialization.
Later on, one must define the three parts of the body by means of three
functions. Their headers are given by the
ATF_TC_HEAD(),
ATF_TC_BODY() and
ATF_TC_CLEANUP() macros,
all of which take the test case name provided to the
ATF_TC()
ATF_TC_WITH_CLEANUP(), or
ATF_TC_WITHOUT_HEAD() macros and the name of the variable
that will hold a pointer to the test case data. Following each of these, a
block of code is expected, surrounded by the opening and closing brackets.
Program initialization
The library provides a way to easily define the test program's
main() function. You should never define one on your own,
but rely on the library to do it for you. This is done by using the
ATF_TP_ADD_TCS() macro, which is passed the name of the
object that will hold the test cases; i.e. the test program instance. This
name can be whatever you want as long as it is a valid variable identifier.
After the macro, you are supposed to provide the body of a function, which
should only use the
ATF_TP_ADD_TC() macro to register the
test cases the test program will execute and return a success error code. The
first parameter of this macro matches the name you provided in the former
call. The success status can be returned using the
atf_no_error() function.
The test case's header can define the meta-data by using the
atf_tc_set_md_var() method, which takes three parameters:
the first one points to the test case data, the second one specifies the
meta-data variable to be set and the third one specifies its value. Both of
them are strings.
Configuration variables
The test case has read-only access to the current configuration variables by
means of the
bool
atf_tc_has_config_var(),
const char *
atf_tc_get_config_var(),
const char *
atf_tc_get_config_var_wd(),
bool
atf_tc_get_config_var_as_bool(),
bool
atf_tc_get_config_var_as_bool_wd(),
long atf_tc_get_config_var_as_long(),
and the
long
atf_tc_get_config_var_as_long_wd() functions, which can be
called in any of the three parts of a test case.
The ‘_wd’ variants take a default value for the variable which is
returned if the variable is not defined. The other functions without the
‘_wd’ suffix
require the variable to be defined.
Access to the source
directory
It is possible to get the path to the test case's source directory from any of
its three components by querying the ‘srcdir’ configuration
variable.
Requiring programs
Aside from the
require.progs meta-data variable available
in the header only, one can also check for additional programs in the test
case's body by using the
atf_tc_require_prog() function,
which takes the base name or full path of a single binary. Relative paths are
forbidden. If it is not found, the test case will be automatically skipped.
Test case finalization
The test case finalizes either when the body reaches its end, at which point the
test is assumed to have
passed, unless any non-fatal errors
were raised using
atf_tc_fail_nonfatal(), or at any explicit
call to
atf_tc_pass(),
atf_tc_fail() or
atf_tc_skip(). These three functions terminate the execution
of the test case immediately. The cleanup routine will be processed afterwards
in a completely automated way, regardless of the test case's termination
reason.
atf_tc_pass() does not take any parameters.
atf_tc_fail(),
atf_tc_fail_nonfatal() and
atf_tc_skip() take a format string and a variable list of
parameters, which describe, in a user-friendly manner, why the test case
failed or was skipped, respectively. It is very important to provide a clear
error message in both cases so that the user can quickly know why the test did
not pass.
Expectations
Everything explained in the previous section changes when the test case
expectations are redefined by the programmer.
Each test case has an internal state called ‘expect’ that describes
what the test case expectations are at any point in time. The value of this
property can change during execution by any of:
-
-
- atf_tc_expect_death(reason,
...)
- Expects the test case to exit prematurely regardless of the
nature of the exit.
-
-
- atf_tc_expect_exit(exitcode,
reason, ...)
- Expects the test case to exit cleanly. If
exitcode is not ‘-1’,
atf-run(1) will validate
that the exit code of the test case matches the one provided in this call.
Otherwise, the exact value will be ignored.
-
-
- atf_tc_expect_fail(reason,
...)
- Any failure (be it fatal or non-fatal) raised in this mode
is recorded. However, such failures do not report the test case as failed;
instead, the test case finalizes cleanly and is reported as
‘expected failure’; this report includes the provided
reason as part of it. If no error is raised while
running in this mode, then the test case is reported as
‘failed’.
This mode is useful to reproduce actual known bugs in tests. Whenever the
developer fixes the bug later on, the test case will start reporting a
failure, signaling the developer that the test case must be adjusted to
the new conditions. In this situation, it is useful, for example, to set
reason as the bug number for tracking purposes.
-
-
- atf_tc_expect_pass()
- This is the normal mode of execution. In this mode, any
failure is reported as such to the user and the test case is marked as
‘failed’.
-
-
- atf_tc_expect_signal(signo,
reason, ...)
- Expects the test case to terminate due to the reception of
a signal. If signo is not ‘-1’,
atf-run(1) will validate
that the signal that terminated the test case matches the one provided in
this call. Otherwise, the exact value will be ignored.
-
-
- atf_tc_expect_timeout(reason,
...)
- Expects the test case to execute for longer than its
timeout.
Helper macros for common
checks
The library provides several macros that are very handy in multiple situations.
These basically check some condition after executing a given statement or
processing a given expression and, if the condition is not met, they report
the test case as failed.
The ‘REQUIRE’ variant of the macros immediately abort the test case
as soon as an error condition is detected by calling the
atf_tc_fail() function. Use this variant whenever it makes
no sense to continue the execution of a test case when the checked condition
is not met. The ‘CHECK’ variant, on the other hand, reports a
failure as soon as it is encountered using the
atf_tc_fail_nonfatal() function, but the execution of the
test case continues as if nothing had happened. Use this variant whenever the
checked condition is important as a result of the test case, but there are
other conditions that can be subsequently checked on the same run without
aborting.
Additionally, the ‘MSG’ variants take an extra set of parameters to
explicitly specify the failure message. This failure message is formatted
according to the
printf(3)
formatters.
ATF_CHECK(),
ATF_CHECK_MSG(),
ATF_REQUIRE() and
ATF_REQUIRE_MSG() take
an expression and fail if the expression evaluates to false.
ATF_CHECK_EQ(),
ATF_CHECK_EQ_MSG(),
ATF_REQUIRE_EQ() and
ATF_REQUIRE_EQ_MSG()
take two expressions and fail if the two evaluated values are not equal.
ATF_CHECK_MATCH(),
ATF_CHECK_MATCH_MSG(),
ATF_REQUIRE_MATCH() and
ATF_REQUIRE_MATCH_MSG() take a regular expression and a
string and fail if the regular expression does not match the given string.
Note that the regular expression is not anchored, so it will match anywhere in
the string.
ATF_CHECK_STREQ(),
ATF_CHECK_STREQ_MSG(),
ATF_REQUIRE_STREQ() and
ATF_REQUIRE_STREQ_MSG() take two strings and fail if the two
are not equal character by character.
ATF_CHECK_ERRNO() and
ATF_REQUIRE_ERRNO()
take, first, the error code that the check is expecting to find in the
errno variable and, second, a boolean expression that,
if evaluates to true, means that a call failed and
errno
has to be checked against the first value.
Utility functions
The following functions are provided as part of the
atf-c-api
API to simplify the creation of a variety of tests. In particular, these are
useful to write tests for command-line interfaces.
void
atf_utils_cat_file(
const char *file,
const char *prefix);
Prints the contents of
file to the standard output, prefixing every line with
the string in prefix.
bool
atf_utils_compare_file(
const char
*file,
const char *contents);
Returns true if the given
file matches exactly the expected inlined
contents.
void
atf_utils_copy_file(
const char
*source,
const char *destination);
Copies the file
source to destination. The
permissions of the file are preserved during the code.
void
atf_utils_create_file(
const char
*file,
const char *contents,
...);
Creates file
with the text given in contents, which is a formatting
string that uses the rest of the variable arguments.
void
atf_utils_file_exists(
const char
*file);
Checks if
file exists.
pid_t
atf_utils_fork(
void);
Forks a process and redirects the
standard output and standard error of the child to files for later validation
with atf_utils_wait(). Fails the test case if the fork
fails, so this does not return an error.
void
atf_utils_free_charpp(
char **argv);
Frees a dynamically-allocated array
of dynamically-allocated strings.
bool
atf_utils_grep_file(
const char
*regexp,
const char *file,
...);
Searches for the
regexp, which is a formatting string representing the
regular expression, in the file. The variable arguments
are used to construct the regular expression.
bool
atf_utils_grep_string(
const char
*regexp,
const char *str,
...);
Searches for the
regexp, which is a formatting string representing the
regular expression, in the literal string str. The
variable arguments are used to construct the regular expression.
char *
atf_utils_readline(
int fd);
Reads a line from the file
descriptor
fd. The line, if any, is returned as a
dynamically-allocated buffer that must be released with
free(3). If there was nothing to
read, returns ‘NULL’.
void
atf_utils_redirect(
const int fd,
const char *file);
Redirects the given file descriptor
fd to file. This function exits
the process in case of an error and does not properly mark the test case as
failed. As a result, it should only be used in subprocesses of the test case;
specially those spawned by atf_utils_fork().
void
atf_utils_wait(
const pid_t pid,
const int expected_exit_status,
const
char *expected_stdout,
const char
*expected_stderr);
Waits and validates the result of a
subprocess spawned with
atf_utils_wait(). The validation
involves checking that the subprocess exited cleanly and returned the code
specified in
expected_exit_status and that its standard
output and standard error match the strings given in
expected_stdout and
expected_stderr.
If any of the
expected_stdout or
expected_stderr strings are prefixed with
‘save:’, then they specify the name of the file into which to
store the stdout or stderr of the subprocess, and no comparison is
performed.
EXAMPLES
The following shows a complete test program with a single test case that
validates the addition operator:
#include <atf-c.h>
ATF_TC(addition);
ATF_TC_HEAD(addition, tc)
{
atf_tc_set_md_var(tc, "descr",
"Sample tests for the addition operator");
}
ATF_TC_BODY(addition, tc)
{
ATF_CHECK_EQ(0 + 0, 0);
ATF_CHECK_EQ(0 + 1, 1);
ATF_CHECK_EQ(1 + 0, 1);
ATF_CHECK_EQ(1 + 1, 2);
ATF_CHECK_EQ(100 + 200, 300);
}
ATF_TC(string_formatting);
ATF_TC_HEAD(string_formatting, tc)
{
atf_tc_set_md_var(tc, "descr",
"Sample tests for the snprintf");
}
ATF_TC_BODY(string_formatting, tc)
{
char buf[1024];
snprintf(buf, sizeof(buf), "a %s", "string");
ATF_CHECK_STREQ_MSG("a string", buf, "%s is not working");
}
ATF_TC(open_failure);
ATF_TC_HEAD(open_failure, tc)
{
atf_tc_set_md_var(tc, "descr",
"Sample tests for the open function");
}
ATF_TC_BODY(open_failure, tc)
{
ATF_CHECK_ERRNO(ENOENT, open("non-existent", O_RDONLY) == -1);
}
ATF_TC(known_bug);
ATF_TC_HEAD(known_bug, tc)
{
atf_tc_set_md_var(tc, "descr",
"Reproduces a known bug");
}
ATF_TC_BODY(known_bug, tc)
{
atf_tc_expect_fail("See bug number foo/bar");
ATF_CHECK_EQ(3, 1 + 1);
atf_tc_expect_pass();
ATF_CHECK_EQ(3, 1 + 2);
}
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, addition);
ATF_TP_ADD_TC(tp, string_formatting);
ATF_TP_ADD_TC(tp, open_failure);
ATF_TP_ADD_TC(tp, known_bug);
return atf_no_error();
}
SEE ALSO
atf-test-program(1),
atf-test-case(4),
atf(7)