Enable windows build static

Author: rhpvorderman

setup.py

@@ -30,12 +30,21 @@
 
 ISA_L_SOURCE = os.path.join("src", "isal", "isa-l")
 
+SYSTEM_IS_UNIX = (sys.platform.startswith("linux") or
+                  sys.platform.startswith("darwin"))
+SYSTEM_IS_WINDOWS = sys.platform.startswith("win")
+
 
 class IsalExtension(Extension):
     """Custom extension to allow for targeted modification."""
     pass
 
 
+MODULES = [IsalExtension("isal.isal_zlib", ["src/isal/isal_zlib.pyx"])]
+if SYSTEM_IS_UNIX:
+    MODULES.append(IsalExtension("isal._isal", ["src/isal/_isal.pyx"]))
+
+
 class BuildIsalExt(build_ext):
     def build_extension(self, ext):
         if not isinstance(ext, IsalExtension):
@@ -57,11 +66,10 @@ def build_extension(self, ext):
             ext.libraries = ["isal"]
         else:
             isa_l_prefix_dir = build_isa_l()
-            if (sys.platform.startswith("linux") or
-                    sys.platform.startswith("darwin")):
+            if SYSTEM_IS_UNIX:
                 ext.extra_objects = [
                     os.path.join(isa_l_prefix_dir, "lib", "libisal.a")]
-            elif sys.platform.startswith("win"):
+            elif SYSTEM_IS_WINDOWS:
                 ext.extra_objects = [
                     os.path.join(isa_l_prefix_dir, "isa-l_static.lib")]
             else:
@@ -110,17 +118,22 @@ def build_isa_l():
     else:  # sched_getaffinity not available on all platforms
         cpu_count = os.cpu_count() or 1  # os.cpu_count() can return None
     run_args = dict(cwd=build_dir, env=build_env)
-    if sys.platform.startswith("linux") or sys.platform.startswith("darwin"):
+    if SYSTEM_IS_UNIX:
         subprocess.run(os.path.join(build_dir, "autogen.sh"), **run_args)
         subprocess.run([os.path.join(build_dir, "configure"),
                         "--prefix", temp_prefix], **run_args)
         subprocess.run(["make", "-j", str(cpu_count)],
                        **run_args)
         subprocess.run(["make", "install"], **run_args)
         shutil.rmtree(build_dir)
-    elif sys.platform.startswith("win"):
+    elif SYSTEM_IS_WINDOWS:
         subprocess.run(["nmake", "/f", "Makefile.nmake"], **run_args)
-        temp_prefix = build_dir
+        Path(temp_prefix, "include").mkdir()
+        print(temp_prefix, file=sys.stderr)
+        shutil.copytree(os.path.join(build_dir, "include"),
+                        Path(temp_prefix, "include", "isa-l"))
+        shutil.copy(os.path.join(build_dir, "isa-l_static.lib"),
+                    os.path.join(temp_prefix, "isa-l_static.lib"))
     else:
         raise NotImplementedError(f"Unsupported platform: {sys.platform}")
     return temp_prefix
@@ -163,8 +176,5 @@ def build_isa_l():
         "Operating System :: MacOS"
     ],
     python_requires=">=3.6",
-    ext_modules=[
-        IsalExtension("isal.isal_zlib", ["src/isal/isal_zlib.pyx"]),
-        IsalExtension("isal._isal", ["src/isal/_isal.pyx"]),
-    ]
+    ext_modules=MODULES
 )

src/isal/__init__.py

@@ -18,8 +18,14 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from ._isal import ISAL_MAJOR_VERSION, ISAL_MINOR_VERSION, \
-    ISAL_PATCH_VERSION, ISAL_VERSION
+try:
+    from ._isal import ISAL_MAJOR_VERSION, ISAL_MINOR_VERSION, \
+        ISAL_PATCH_VERSION, ISAL_VERSION
+except ImportError:  # Not available on windows
+    ISAL_MAJOR_VERSION = None
+    ISAL_MINOR_VERSION = None
+    ISAL_PATCH_VERSION = None
+    ISAL_VERSION = None
 
 __all__ = [
     "ISAL_MAJOR_VERSION",