Bug 1407432 - Move system wrapper generation to moz.build; r=froydnj

The make-system-wrappers.py invocation is largely identical to
make-stl-wrappers.py, though this script generates wrappers for both the
STL headers and every other system header that can be used.

Note that the nsprpub script didn't create multiple layers of
subdirectories properly, so for example the 'ia64/sys/inline.h' wrapper
is now generated properly. Additionally, MOZ_SYSTEM_ICU define was
incorrectly using '#ifdef' instead of '#if ... == 1', which causes those
unicode headers to have wrappers when they shouldn't. These will show up
as differences when comparing the Makefile output to the moz.build
output.

MozReview-Commit-ID: KvQAawfzXao

--HG--
extra : rebase_source : 758e325c6ec192d83fcfa10f8c878ba2629e45a3

config/Makefile.in

@@ -32,29 +32,6 @@ endif
 
 include $(topsrcdir)/config/rules.mk
 
-ifdef WRAP_SYSTEM_INCLUDES
-export-preqs = \
-  $(call mkdir_deps,system_wrappers) \
-  $(NULL)
-
-export:: $(export-preqs)
-	$(PYTHON) -m mozbuild.action.preprocessor $(DEFINES) $(ACDEFINES) \
-		-DMOZ_TREE_CAIRO=$(MOZ_TREE_CAIRO) \
-		-DMOZ_TREE_PIXMAN=$(MOZ_TREE_PIXMAN) \
-		-DMOZ_SYSTEM_HUNSPELL=$(MOZ_SYSTEM_HUNSPELL) \
-		-DMOZ_SYSTEM_BZ2=$(MOZ_SYSTEM_BZ2) \
-		-DMOZ_SYSTEM_ZLIB=$(MOZ_SYSTEM_ZLIB) \
-		-DMOZ_SYSTEM_PNG=$(MOZ_SYSTEM_PNG) \
-		-DMOZ_SYSTEM_JPEG=$(MOZ_SYSTEM_JPEG) \
-		-DMOZ_SYSTEM_LIBEVENT=$(MOZ_SYSTEM_LIBEVENT) \
-		-DMOZ_SYSTEM_LIBVPX=$(MOZ_SYSTEM_LIBVPX) \
-		-DMOZ_SYSTEM_ICU=$(MOZ_SYSTEM_ICU) \
-		$(srcdir)/system-headers $(srcdir)/stl-headers | $(PERL) $(topsrcdir)/nsprpub/config/make-system-wrappers.pl system_wrappers
-	$(INSTALL) system_wrappers $(DIST)
-
-GARBAGE_DIRS += system_wrappers
-endif
-
 GARBAGE += \
   $(FINAL_LINK_COMPS) $(FINAL_LINK_LIBS) $(FINAL_LINK_COMP_NAMES) $(srcdir)/*.pyc *.pyc
 

config/make-system-wrappers.py

@@ -0,0 +1,23 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+from __future__ import print_function
+import os
+import sys
+from mozbuild.util import FileAvoidWrite
+
+header_template = '''#pragma GCC system_header
+#pragma GCC visibility push(default)
+#include_next <%(header)s>
+#pragma GCC visibility pop
+'''
+
+
+# The 'unused' arg is the output file from the file_generate action. We actually
+# generate all the files in header_list
+def gen_wrappers(unused, outdir, *header_list):
+    for header in header_list:
+        with FileAvoidWrite(os.path.join(outdir, header)) as f:
+            f.write(header_template % {
+                'header': header,
+            })

config/moz.build

@@ -63,3 +63,14 @@ if CONFIG['WRAP_STL_INCLUDES']:
         stl.script = 'make-stl-wrappers.py:gen_wrappers'
         stl.flags = [output_dir, stl_compiler, template_file]
         stl.flags.extend(stl_headers)
+
+if CONFIG['WRAP_SYSTEM_INCLUDES']:
+    include('system-headers.mozbuild')
+    output_dir = '../dist/system_wrappers'
+    outputs = tuple(['system-header.sentinel'] + ['%s/%s' % (output_dir, h) for h in stl_headers + system_headers])
+    GENERATED_FILES += [outputs]
+    system = GENERATED_FILES[outputs]
+    system.script = 'make-system-wrappers.py:gen_wrappers'
+    system.flags = [output_dir]
+    system.flags.extend(stl_headers)
+    system.flags.extend(system_headers)