There are some platforms where 'char' is unsigned, by default
(RPi, s390x to name a few). And because of how test_demo is
written we are experiencing some test cases failing there. For
instance: /xdr/struct-scalar is failing. This is because in the
test (test_struct_scalar()), we have a struct with two chars. One
is initialized to 0xca, the other 0xfe (note that both have the
MSB set). The XDR encoder (xdr_TestStructScalar()) then calls
xdr_char() on both of them. But XDR itself has no notion of
char type, so under the hood, it expands it to int [1] and calls
xdr_int(). And this is where the problem lies. On platforms where
char is signed, the integer expansion results in 0xffffffca, but
on platforms where char is unsigned it results in 0x000000ca. Two
distinct results.
The test then goes and compares the encoded buffer with an
expected one (memcmp(), read from the disk earlier).
This poses no problem for real life use, because when decoding
those chars back, the padding is thrown away.
To avoid tickling this issue, use values that don't have the MSB
set.
1: https://git.linux-nfs.org/?p=steved/libtirpc.git;a=blob;f=src/xdr.c;h=28d1382cc4853ecf1238d792af5016160435d1e0;hb=HEAD#l487
Fixes: 40cbaa8fbe rpcgen: add test case for XDR serialization
Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
The test_demo program compares whether XDR encoded data match the
expected output as read from a file. But the file path is not
absolute and thus relative to CWD which means the program can run
only from one specific directory.
Do what we do in the rest of our test suite: define 'abs_srcdir'
macro and prefix the path with it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
This will eliminate the need to call xdr_free to clear
pointers from data structures.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Test the serialization done by libtirpc, so that when we later
switch to our own code, we can prove wire compatibility.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
