[PATCH libkdumpfile] tests: skip tests which apply to disabled compression

[Stephen Brennan <stephen.s.brennan@oracle.com>]

If configured --without-libzstd, for example, the diskdump-basic-zstd
test will return an ERROR code, causing "make check" to fail. Even using
XFAIL_TESTS will not resolve the error, because the return code is
ERROR, not FAIL.

Instead, conditionally include the tests based on whether we are
compiling with each compression format. This way, we don't test
unsupported features.

Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
---
 m4/compression.m4 |  1 +
 tests/Makefile.am | 17 +++++++++++++----
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/m4/compression.m4 b/m4/compression.m4
index 6755ef1..8cb7ce2 100644
--- a/m4/compression.m4
+++ b/m4/compression.m4
@@ -32,4 +32,5 @@ AC_SUBST([$2][_REQUIRES])
 AC_SUBST([$2][_CFLAGS])
 AC_SUBST([$2][_LIBS])
 AC_SUBST([$2][_PC_LIBS])
+AM_CONDITIONAL(HAVE_$2, test "x$have_$1" = xyes)
 ])
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 0c03b20..8ac90b3 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -196,10 +196,6 @@ test_scripts = \
 	diskdump-empty-s390x \
 	diskdump-empty-x86_64 \
 	diskdump-basic-raw \
-	diskdump-basic-zlib \
-	diskdump-basic-lzo \
-	diskdump-basic-snappy \
-	diskdump-basic-zstd \
 	diskdump-flat-raw \
 	diskdump-multiread \
 	diskdump-excluded \
@@ -331,6 +327,19 @@ test_scripts = \
 	xlat-xen-x86_64-4.6-bigmem \
 	zero-size
 
+if HAVE_ZSTD
+test_scripts += diskdump-basic-zstd
+endif
+if HAVE_ZLIB
+test_scripts += diskdump-basic-zlib
+endif
+if HAVE_LZO
+test_scripts += diskdump-basic-lzo
+endif
+if HAVE_SNAPPY
+test_scripts += diskdump-basic-snappy
+endif
+
 dist_check_DATA = \
 	addrmap-single-begin.expect \
 	addrmap-single-middle.expect \
-- 
2.39.3