scripts: waifulib: add tool for building with Emscripten's Clang wrapper

scripts/waifulib/c_emscripten.py

@@ -0,0 +1,100 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 vi:ts=4:noexpandtab
+
+from waflib.Tools import ccroot, gcc, gxx
+from waflib.Configure import conf
+from waflib.TaskGen import feature, after_method
+from waflib import Utils
+
+@conf
+def get_emscripten_version(conf, cc):
+	k = conf.get_cc_version(cc, clang=True)
+
+	if '__EMSCRIPTEN__' not in k:
+		conf.fatal('Could not determine the emscripten compiler version')
+
+	conf.env.DEST_OS = 'emscripten'
+	conf.env.DEST_CPU = 'wasm'
+
+@conf
+def find_emcc(conf):
+	cc = conf.find_program(['emcc'], var='CC')
+	conf.get_emscripten_version(cc)
+	conf.env.CC_NAME = 'clang'
+
+@conf
+def find_emxx(conf):
+	cxx = conf.find_program(['em++'], var='CXX')
+	conf.get_emscripten_version(cxx)
+	conf.env.CXX_NAME = 'clang'
+
+@conf
+def gcc_modifier_emscripten(conf):
+	v = conf.env
+
+	conf.env.cshlib_PATTERN = 'lib%s.wasm'
+	conf.env.cprogram_PATTERN = '%s.html'
+
+	conf.env.CFLAGS_cshlib = ['-fPIC', '-sSIDE_MODULE=1']
+	conf.env.CFLAGS_cstlib = ['-fPIC']
+	conf.env.CFLAGS_cprogram = ['-sMAIN_MODULE=1']
+
+	conf.env.LINKFLAGS_cshlib = ['-sSIDE_MODULE=1']
+	conf.env.LINKFLAGS_cprogram = ['-sMAIN_MODULE=1']
+
+@conf
+def gxx_modifier_emscripten(conf):
+	v = conf.env
+
+	conf.env.cxxshlib_PATTERN = 'lib%s.wasm'
+	conf.env.cxxprogram_PATTERN = '%s.html'
+	conf.env.CXXFLAGS_cxxshlib = ['-fPIC', '-sSIDE_MODULE=1']
+	conf.env.CXXFLAGS_cxxstlib = ['-fPIC']
+	conf.env.CXXFLAGS_cxxprogram = ['-sMAIN_MODULE=1']
+
+	conf.env.LINKFLAGS_cxxshlib = ['-sSIDE_MODULE=1']
+	conf.env.LINKFLAGS_cxxprogram = ['-sMAIN_MODULE=1']
+
+@feature('cxxprogram', 'cprogram')
+@after_method('apply_link')
+def apply_indexhtml(self):
+	if self.env.DEST_OS != 'emscripten':
+		return
+
+	tsk = self.link_task
+	node = tsk.outputs[0]
+
+	tsk.outputs.append(node.change_ext('.js'))
+	tsk.outputs.append(node.change_ext('.wasm'))
+
+	if '--preload-file' in getattr(self, 'linkflags', []) + self.env.LINKFLAGS:
+		tsk.outputs.append(node.change_ext('.data'))
+
+	inst_to = getattr(self, 'special_install_path', None)
+	if inst_to:
+		self.add_install_as(install_to=inst_to + '/index.html',
+			install_from=tsk.outputs[0], chmod=Utils.O644, task=tsk)
+
+		self.add_install_files(install_to=inst_to,
+			install_from=tsk.outputs[1:], chmod=Utils.O644, task=tsk)
+
+def configure(conf):
+	if not conf.env.CC:
+		conf.find_emcc()
+		conf.gcc_common_flags()
+		conf.gcc_modifier_platform()
+		conf.cc_load_tools()
+		conf.cc_add_flags()
+		conf.link_add_flags()
+
+	if not conf.env.AR:
+		conf.find_program(['emar'], var='AR')
+		conf.find_ar()
+
+	if not conf.env.CXX:
+		conf.find_emxx()
+		conf.gxx_common_flags()
+		conf.gxx_modifier_platform()
+		conf.cxx_load_tools()
+		conf.cxx_add_flags()
+		conf.link_add_flags()

scripts/waifulib/xcompile.py

@@ -539,6 +539,8 @@ def options(opt):
 		help='enable building for PlayStation Vita [default: %(default)s]')
 	xc.add_option('--sailfish', action='store', dest='SAILFISH', default = None,
 		help='enable building for Sailfish/Aurora')
+	xc.add_option('--emscripten', action='store_true', dest='EMSCRIPTEN', default = None,
+		help='enable building for Emscripten')
 
 def configure(conf):
 	if conf.options.ANDROID_OPTS:
@@ -627,11 +629,21 @@ def configure(conf):
 		conf.env.LIB_M = ['m']
 		conf.env.VRTLD = ['vrtld']
 		conf.env.DEST_OS = 'psvita'
+	elif conf.options.EMSCRIPTEN:
+		# Emscripten compiler is just wrapper to clang
+		# But we need to setup platform modifiers, they all are contained inside c_emscripten.py for now
+		# In future, that could be upstreamed to waf itself and this wouldn't be needed
+		conf.environ['CC'] = 'emcc'
+		conf.environ['CXX'] = 'em++'
+		conf.environ['AR'] = 'emar'
+		conf.environ['STRIP'] = 'emstrip'
+		conf.environ['OBJCOPY'] = 'llvm-objcopy'
+		conf.load('c_emscripten')
 
 	conf.env.MAGX = conf.options.MAGX
 	conf.env.MSVC_WINE = conf.options.MSVC_WINE
 	conf.env.SAILFISH = conf.options.SAILFISH
-	MACRO_TO_DESTOS = OrderedDict({ '__ANDROID__' : 'android', '__SWITCH__' : 'nswitch', '__vita__' : 'psvita', '__wasi__': 'wasi' })
+	MACRO_TO_DESTOS = OrderedDict({ '__ANDROID__' : 'android', '__SWITCH__' : 'nswitch', '__vita__' : 'psvita', '__wasi__': 'wasi', '__EMSCRIPTEN__' : 'emscripten' })
 	for k in c_config.MACRO_TO_DESTOS:
 		MACRO_TO_DESTOS[k] = c_config.MACRO_TO_DESTOS[k] # ordering is important
 	c_config.MACRO_TO_DESTOS  = MACRO_TO_DESTOS