This test uses the same style of re-packing variadic arguments through
two layers of variadic calls, and compares that call chain against one
direct variadic call.
The outer function uses the same kind of re-packing used in
src/libfaketime.c's syscall (leading to real_syscall), but the inner
functions use different assumptions about the types of each argument.
This is not an entirely comprehensive test, because we only define two
different inner function signatures. If some particular syscall is
breaking when intercepted, consider adding something like its expected
function signature in test/variadic/inner.c, and invoke it in
test/variadic/main.c.
Note that we don't test any floating point types (those types are
typically passed in registers in x86-64, not on the stack, and are
also not used for any syscall that i'm aware of).
Most of these snippets are likely to have some env var that causes the
data to hold constant, while the data will otherwise be likely to vary
over time.
This framework offers a way to test those snippets, by dropping the
variable and an example value in the test/snippets/FOO.variable
one-line file.
Note that the test/snippets/syscall.c snippet is *not* expected to
vary over time (or to differ when any given variable is set), so we
simply don't add any test/snippets/syscall.variable file to avoid it
being tested in this way.
We want to make it easier to test a bunch of different functions that
might be invoked in constructors of other libraries.
It seems conceivable that with these snippets, we could design other
tests that also work across a wide range of intercepted functions.
A single program that invokes getrandom() repeatedly should end up
with the same stream of bytes, regardless of how it chunks up the
reading from the entropy source.
This test already passses. I'm including it because it seems
like a useful confirmation.
In trying to test the experimental getrandom features, I found a few
minor problems. These changes should make it easier to test.
After building, the developer can now just do:
make -C test randomtest
This will do a basic verfication that the feature works as expected.
I haven't tried to integrate this with the overall "make test". To do
that right, it should condition the test on the definition of
FAKE_RANDOM.
Used (emacs) M-x untabify for whole faketime.c as the prevailing
style in that file used spaces for indentation.
Used M-x delete-trailing-whitespace to all files that had either
trailing whitespace or empty lines at the end of file to remove
those.
* Use variables for compiler and linker flags.
* Use variables for source/object files, library names and sonames.
* Use proper targets instead of phony targets to build the shared
libraries.
Signed-off-by: Lukas Fleischer <info@cryptocrack.de>
