Fix make distcheck for Python test suite

Python tests assumed the build and source directories were identical, which
holds for an in-tree build but not for `make distcheck`, where automake
builds in a separate _build/sub directory. Under distcheck the wolfssl
binary was searched for under the source tree (where it did not exist),
fixture files were opened via cwd-relative paths, and the certs/ tree was
not distributed at all. As a result every Python test either failed to
find the wolfssl binary or skipped because certs/ was missing.

- Add certs/ to EXTRA_DIST so it ships in the distribution tarball.
- Teach wolfclu_test.py to locate the wolfssl binary and certs/ via the
  build/source directories exported through AM_TESTS_ENVIRONMENT, with
  sensible fallbacks for direct script invocation.
- Replace cwd-relative "./tests/<dir>" paths in dgst, hash, and
  x509-process tests with paths derived from each test file's location,
  so they resolve correctly regardless of where the test is run from.

Author: julek-wolfssl

Makefile.am

@@ -21,6 +21,9 @@ dist_noinst_SCRIPTS=
 
 TEST_EXTENSIONS = .sh .py
 PY_LOG_COMPILER = $(PYTHON)
+AM_TESTS_ENVIRONMENT = \
+    WOLFCLU_BUILDDIR='$(abs_top_builddir)'; export WOLFCLU_BUILDDIR; \
+    WOLFCLU_SRCDIR='$(abs_top_srcdir)'; export WOLFCLU_SRCDIR;
 
 #includes additional rules from aminclude.am
 @INC_AMINCLUDE@
@@ -32,6 +35,7 @@ DISTCLEANFILES+= aminclude.am
 ACLOCAL_AMFLAGS= -I m4
 
 EXTRA_DIST+= tests
+EXTRA_DIST+= certs
 EXTRA_DIST+= manpages
 EXTRA_DIST+= README.md
 EXTRA_DIST+= LICENSE

tests/dgst/dgst-test.py

@@ -9,7 +9,7 @@
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 from wolfclu_test import CERTS_DIR, run_wolfssl, test_main
 
-DGST_DIR = os.path.join(".", "tests", "dgst")
+DGST_DIR = os.path.dirname(os.path.abspath(__file__))
 
 
 class DgstVerifyTest(unittest.TestCase):

tests/hash/hash-test.py

@@ -8,7 +8,7 @@
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 from wolfclu_test import CERTS_DIR, run_wolfssl, test_main
 
-HASH_DIR = os.path.join(".", "tests", "hash")
+HASH_DIR = os.path.dirname(os.path.abspath(__file__))
 CERT_FILE = os.path.join(CERTS_DIR, "ca-cert.pem")
 
 

tests/wolfclu_test.py

@@ -12,9 +12,18 @@
 
 
 def _find_wolfssl_bin():
-    """Locate the wolfssl binary, searching common build output paths."""
+    """Locate the wolfssl binary, searching common build output paths.
+
+    Under `make distcheck`, the build directory differs from the source
+    directory, so the binary is produced next to where tests are invoked
+    (the current working directory) rather than under the source tree.
+    Honour WOLFCLU_BUILDDIR if set by the test harness, then fall back to
+    the current working directory, and finally the source tree.
+    """
+    builddir = os.environ.get("WOLFCLU_BUILDDIR") or os.getcwd()
     if platform.system() == "Windows":
         candidates = [
+            os.path.join(builddir, "wolfssl.exe"),
             os.path.join(_PROJECT_ROOT, "x64", "Debug", "wolfssl.exe"),
             os.path.join(_PROJECT_ROOT, "x64", "Release", "wolfssl.exe"),
             os.path.join(_PROJECT_ROOT, "Debug", "wolfssl.exe"),
@@ -23,6 +32,7 @@ def _find_wolfssl_bin():
         ]
     else:
         candidates = [
+            os.path.join(builddir, "wolfssl"),
             os.path.join(_PROJECT_ROOT, "wolfssl"),
         ]
 
@@ -34,8 +44,21 @@ def _find_wolfssl_bin():
     return candidates[0]
 
 
+def _find_certs_dir():
+    """Locate the certs directory (source tree or extracted tarball)."""
+    srcdir = os.environ.get("WOLFCLU_SRCDIR")
+    candidates = []
+    if srcdir:
+        candidates.append(os.path.join(srcdir, "certs"))
+    candidates.append(os.path.join(_PROJECT_ROOT, "certs"))
+    for path in candidates:
+        if os.path.isdir(path):
+            return path
+    return candidates[-1]
+
+
 WOLFSSL_BIN = _find_wolfssl_bin()
-CERTS_DIR = os.path.join(_PROJECT_ROOT, "certs")
+CERTS_DIR = _find_certs_dir()
 
 
 def run_wolfssl(*args, stdin_data=None, timeout=60):

tests/x509/x509-process-test.py

@@ -10,7 +10,7 @@
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 from wolfclu_test import WOLFSSL_BIN, CERTS_DIR, run_wolfssl, test_main
 
-TESTS_X509_DIR = os.path.join(".", "tests", "x509")
+TESTS_X509_DIR = os.path.dirname(os.path.abspath(__file__))
 HAS_OPENSSL = shutil.which("openssl") is not None