This is the first of a 2-part patch set that fixes slow DSO sorting behavior in
the dynamic loader, as reported in BZ #17645. In order to facilitate such a
large modification to the dynamic loader, this first patch implements a testing
framework for validating shared object sorting behavior, to enable comparison
between old/new sorting algorithms, and any later enhancements.
This testing infrastructure consists of a Python script
scripts/dso-ordering-test.py' which takes in a description language, consisting
of strings that describe a set of link dependency relations between DSOs, and
generates testcase programs and Makefile fragments to automatically test the
described situation, for example:
a->b->c->d # four objects linked one after another
a->[bc]->d;b->c # a depends on b and c, which both depend on d,
# b depends on c (b,c linked to object a in fixed order)
a->b->c;{+a;%a;-a} # a, b, c serially dependent, main program uses
# dlopen/dlsym/dlclose on object a
a->b->c;{}!->[abc] # a, b, c serially dependent; multiple tests generated
# to test all permutations of a, b, c ordering linked
# to main program
(Above is just a short description of what the script can do, more
documentation is in the script comments.)
Two files containing several new tests, elf/dso-sort-tests-[12].def are added,
including test scenarios for BZ #15311 and Redhat issue #1162810 [1].
Due to the nature of dynamic loader tests, where the sorting behavior and test
output occurs before/after main(), generating testcases to use
support/test-driver.c does not suffice to control meaningful timeout for ld.so.
Therefore a new utility program 'support/test-run-command', based on
test-driver.c/support_test_main.c has been added. This does the same testcase
control, but for a program specified through a command-line rather than at the
source code level. This utility is used to run the dynamic loader testcases
generated by dso-ordering-test.py.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1162810
Signed-off-by: Chung-Lin Tang <cltang@codesourcery.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This subdirectory contains infrastructure which is not put into
installed libraries, but may be linked into programs (installed or
not) and tests.
# Error-checking wrappers
These wrappers test for error return codes an terminate the process on
error. They are declared in these header files:
* support.h
* xsignal.h
* xthread.h
* xtime.h
In general, new wrappers should be added to support.h if possible.
However, support.h must remain fully compatible with C90 and therefore
cannot include headers which use identifers not reserved in C90. If
the wrappers need additional types, additional headers such as
signal.h need to be introduced.
# Test framework
The test framework provides a main program for tests, including a
timeout for hanging tests. See README-testing.c for a minimal
example, and test-driver.c for details how to use it. The following
header files provide related declarations:
* check.h
* temp_file.h
* test-driver.h
For tests that make use of struct timespec, the following header files
contain additional macros and helper functions:
* timespec.h
e6fd79f379