build-sys: generate systemd/id128-constants.h in setup.py

Fixes #7.

Author: dekkers

Makefile

@@ -13,10 +13,7 @@ builddir := $(shell $(PYTHON) -c '$(buildscript)')
 
 all: build
 
-systemd/id128-constants.h: $(INCLUDE_DIR)/systemd/sd-messages.h
-	$(SED) -n -r 's/,//g; s/#define (SD_MESSAGE_[A-Z0-9_]+)\s.*/add_id(m, "\1", \1) JOINER/p' <$< >$@
-
-build: systemd/id128-constants.h
+build:
 	$(PYTHON) setup.py build
 
 install:

setup.py

@@ -1,7 +1,25 @@
 import sys, os
 from distutils.core import setup, Extension
+from distutils.command.build_ext import build_ext
 from subprocess import Popen, PIPE, check_output
 
+
+class build_ext_generate_id128_header(build_ext):
+    def run(self):
+        if not self.dry_run and not os.path.exists("systemd/id128-constants.h"):
+            constants = []
+            with open("/usr/include/systemd/sd-messages.h") as f:
+                for line in f:
+                    if line.startswith('#define SD'):
+                        constants.append(line.split()[1])
+
+            with open("systemd/id128-constants.h", "w") as f:
+                for c in constants:
+                    f.write('add_id(m, "{0}", {0}) JOINER\n'.format(c))
+
+        return build_ext.run(self)
+
+
 def call(*cmd):
     cmd = Popen(cmd,
                 stdout=PIPE, stderr=PIPE,
@@ -84,4 +102,5 @@ def lib(*names, **kw):
                       _reader,
                       _daemon,
                       id128,
-                      login])
+                      login],
+       cmdclass = {'build_ext': build_ext_generate_id128_header})