Roll IDL to Dartium37 (r181268)

bindings/scripts/code_generator_v8.py

+# Copyright (C) 2013 Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Generate Blink V8 bindings (.h and .cpp files).
+
+If run itself, caches Jinja templates (and creates dummy file for build,
+since cache filenames are unpredictable and opaque).
+
+This module is *not* concurrency-safe without care: bytecode caching creates
+a race condition on cache *write* (crashes if one process tries to read a
+partially-written cache). However, if you pre-cache the templates (by running
+the module itself), then you can parallelize compiling individual files, since
+cache *reading* is safe.
+
+Input: An object of class IdlDefinitions, containing an IDL interface X
+Output: V8X.h and V8X.cpp
+
+Design doc: http://www.chromium.org/developers/design-documents/idl-compiler
+"""
+
+import os
+import posixpath
+import re
+import sys
+
+# Path handling for libraries and templates
+# Paths have to be normalized because Jinja uses the exact template path to
+# determine the hash used in the cache filename, and we need a pre-caching step
+# to be concurrency-safe. Use absolute path because __file__ is absolute if
+# module is imported, and relative if executed directly.
+# If paths differ between pre-caching and individual file compilation, the cache
+# is regenerated, which causes a race condition and breaks concurrent build,
+# since some compile processes will try to read the partially written cache.
+module_path, module_filename = os.path.split(os.path.realpath(__file__))
+third_party_dir = os.path.normpath(os.path.join(
+    module_path, os.pardir, os.pardir, os.pardir, os.pardir))
+templates_dir = os.path.normpath(os.path.join(
+    module_path, os.pardir, 'templates'))
+# Make sure extension is .py, not .pyc or .pyo, so doesn't depend on caching
+module_pyname = os.path.splitext(module_filename)[0] + '.py'
+
+# jinja2 is in chromium's third_party directory.
+# Insert at 1 so at front to override system libraries, and
+# after path[0] == invoking script dir
+sys.path.insert(1, third_party_dir)
+import jinja2
+
+import idl_types
+from idl_types import IdlType
+import v8_callback_interface
+from v8_globals import includes, interfaces
+import v8_interface
+import v8_types
+from v8_utilities import capitalize, cpp_name, conditional_string, v8_class_name
+
+
+class CodeGeneratorV8(object):
+    def __init__(self, interfaces_info, cache_dir):
+        interfaces_info = interfaces_info or {}
+        self.interfaces_info = interfaces_info
+        self.jinja_env = initialize_jinja_env(cache_dir)
+
+        # Set global type info
+        idl_types.set_ancestors(dict(
+            (interface_name, interface_info['ancestors'])
+            for interface_name, interface_info in interfaces_info.iteritems()
+            if interface_info['ancestors']))
+        IdlType.set_callback_interfaces(set(
+            interface_name
+            for interface_name, interface_info in interfaces_info.iteritems()
+            if interface_info['is_callback_interface']))
+        IdlType.set_implemented_as_interfaces(dict(
+            (interface_name, interface_info['implemented_as'])
+            for interface_name, interface_info in interfaces_info.iteritems()
+            if interface_info['implemented_as']))
+        IdlType.set_garbage_collected_types(set(
+            interface_name
+            for interface_name, interface_info in interfaces_info.iteritems()
+            if 'GarbageCollected' in interface_info['inherited_extended_attributes']))
+        IdlType.set_will_be_garbage_collected_types(set(
+            interface_name
+            for interface_name, interface_info in interfaces_info.iteritems()
+            if 'WillBeGarbageCollected' in interface_info['inherited_extended_attributes']))
+        v8_types.set_component_dirs(dict(
+            (interface_name, interface_info['component_dir'])
+            for interface_name, interface_info in interfaces_info.iteritems()))
+
+    def generate_code(self, definitions, interface_name):
+        """Returns .h/.cpp code as (header_text, cpp_text)."""
+        try:
+            interface = definitions.interfaces[interface_name]
+        except KeyError:
+            raise Exception('%s not in IDL definitions' % interface_name)
+
+        # Store other interfaces for introspection
+        interfaces.update(definitions.interfaces)
+
+        # Set local type info
+        IdlType.set_callback_functions(definitions.callback_functions.keys())
+        IdlType.set_enums((enum.name, enum.values)
+                          for enum in definitions.enumerations.values())
+
+        # Select appropriate Jinja template and contents function
+        if interface.is_callback:
+            header_template_filename = 'callback_interface.h'
+            cpp_template_filename = 'callback_interface.cpp'
+            generate_contents = v8_callback_interface.generate_callback_interface
+        else:
+            header_template_filename = 'interface.h'
+            cpp_template_filename = 'interface.cpp'
+            generate_contents = v8_interface.generate_interface
+        header_template = self.jinja_env.get_template(header_template_filename)
+        cpp_template = self.jinja_env.get_template(cpp_template_filename)
+
+        # Generate contents (input parameters for Jinja)
+        template_contents = generate_contents(interface)
+        template_contents['code_generator'] = module_pyname
+
+        # Add includes for interface itself and any dependencies
+        interface_info = self.interfaces_info[interface_name]
+        template_contents['header_includes'].add(interface_info['include_path'])
+        template_contents['header_includes'] = sorted(template_contents['header_includes'])
+        includes.update(interface_info.get('dependencies_include_paths', []))
+        template_contents['cpp_includes'] = sorted(includes)
+
+        # Render Jinja templates
+        header_text = header_template.render(template_contents)
+        cpp_text = cpp_template.render(template_contents)
+        return header_text, cpp_text
+
+
+def initialize_jinja_env(cache_dir):
+    jinja_env = jinja2.Environment(
+        loader=jinja2.FileSystemLoader(templates_dir),
+        # Bytecode cache is not concurrency-safe unless pre-cached:
+        # if pre-cached this is read-only, but writing creates a race condition.
+        bytecode_cache=jinja2.FileSystemBytecodeCache(cache_dir),
+        keep_trailing_newline=True,  # newline-terminate generated files
+        lstrip_blocks=True,  # so can indent control flow tags
+        trim_blocks=True)
+    jinja_env.filters.update({
+        'blink_capitalize': capitalize,
+        'conditional': conditional_if_endif,
+        'runtime_enabled': runtime_enabled_if,
+        })
+    return jinja_env
+
+
+# [Conditional]
+def conditional_if_endif(code, conditional_string):
+    # Jinja2 filter to generate if/endif directive blocks
+    if not conditional_string:
+        return code
+    return ('#if %s\n' % conditional_string +
+            code +
+            '#endif // %s\n' % conditional_string)
+
+
+# [RuntimeEnabled]
+def runtime_enabled_if(code, runtime_enabled_function_name):
+    if not runtime_enabled_function_name:
+        return code
+    # Indent if statement to level of original code
+    indent = re.match(' *', code).group(0)
+    return ('%sif (%s()) {\n' % (indent, runtime_enabled_function_name) +
+            '    %s\n' % '\n    '.join(code.splitlines()) +
+            '%s}\n' % indent)
+
+
+################################################################################
+
+def main(argv):
+    # If file itself executed, cache templates
+    try:
+        cache_dir = argv[1]
+        dummy_filename = argv[2]
+    except IndexError as err:
+        print 'Usage: %s CACHE_DIR DUMMY_FILENAME' % argv[0]
+        return 1
+
+    # Cache templates
+    jinja_env = initialize_jinja_env(cache_dir)
+    template_filenames = [filename for filename in os.listdir(templates_dir)
+                          # Skip .svn, directories, etc.
+                          if filename.endswith(('.cpp', '.h'))]
+    for template_filename in template_filenames:
+        jinja_env.get_template(template_filename)
+
+    # Create a dummy file as output for the build system,
+    # since filenames of individual cache files are unpredictable and opaque
+    # (they are hashes of the template path, which varies based on environment)
+    with open(dummy_filename, 'w') as dummy_file:
+        pass  # |open| creates or touches the file
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv))