Tools/Scripts/dump-class-layout - WebKit - Git at Google

 #!/usr/bin/env python

 # Copyright (C) 2011-2015 Apple 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:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. 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.
 #
 # THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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.

 import re
 import sys
 import getopt
 import argparse
 import os
 import subprocess
 from sets import Set


 framework = "WebCore"
 build_directory = ""
 config = "Release"
 arch = None

 def webkit_build_dir():
     scriptpath = os.path.dirname(os.path.realpath(__file__))
     return subprocess.check_output([os.path.join(scriptpath, "webkit-build-directory"), "--top-level"]).strip()

 def developer_dir():
     return subprocess.check_output(["xcode-select", "--print-path"])

 def import_lldb():
     xcode_contents_path = os.path.split(developer_dir())[0]
     lldb_framework_path = os.path.join(xcode_contents_path, "SharedFrameworks", "LLDB.framework", "Resources", "Python")
     sys.path.append(lldb_framework_path)

     LLDB_MODULE_NAME = "lldb"
     try:
         globals()[LLDB_MODULE_NAME] = __import__(LLDB_MODULE_NAME)
     except ImportError:
         print "Failed to import {} from {}".format(LLDB_MODULE_NAME, lldb_framework_path)
         sys.exit(1)

 def verify_type(target, type):
     typename = type.GetName()
     seenOffset = Set()
     (end_offset, padding) = verify_type_recursive(target, type, None, 0, 0, 0, seenOffset)
     byte_size = type.GetByteSize()
     print 'Total byte size: %u' % (byte_size)
     print 'Total pad bytes: %u' % (padding)
     if padding > 0:
         print 'Padding percentage: %2.2f %%' % ((float(padding) / float(byte_size)) * 100.0)
     print

 def verify_type_recursive(target, type, member_name, depth, base_offset, padding, seenOffset):
     prev_end_offset = base_offset
     typename = type.GetName()
     byte_size = type.GetByteSize()
     if member_name and member_name != typename:
         print '%+4u <%3u> %s%s %s;' % (base_offset, byte_size, '    ' * depth, typename, member_name)
     else:
         print '%+4u {%3u} %s%s' % (base_offset, byte_size, '    ' * depth, typename)

     members = type.members
     if members:
         for member_idx, member in enumerate(members):
             member_type = member.GetType()
             member_canonical_type = member_type.GetCanonicalType()
             member_type_class = member_canonical_type.GetTypeClass()
             member_name = member.GetName()
             member_offset = member.GetOffsetInBytes()
             member_total_offset = member_offset + base_offset
             member_byte_size = member_type.GetByteSize()
             member_is_class_or_struct = False

             if (member_offset, member_name) in seenOffset:
                 continue
             seenOffset.add((member_offset, member_name))

             if member_type_class == lldb.eTypeClassStruct or member_type_class == lldb.eTypeClassClass:
                 member_is_class_or_struct = True
             if member_idx == 0 and member_offset == target.GetAddressByteSize() and type.IsPolymorphicClass():
                 ptr_size = target.GetAddressByteSize()
                 print '%+4u <%3u> %s__vtbl_ptr_type * _vptr;' % (prev_end_offset, ptr_size, '    ' * (depth + 1))
                 prev_end_offset = ptr_size
             else:
                 if prev_end_offset < member_total_offset:
                     member_padding = member_total_offset - prev_end_offset
                     padding = padding + member_padding
                     print '%+4u <%3u> %s<PADDING>' % (prev_end_offset, member_padding, '    ' * (depth + 1))

             if member_is_class_or_struct:
                 (prev_end_offset, padding) = verify_type_recursive(target, member_canonical_type, member_name, depth + 1, member_total_offset, padding, seenOffset)
             else:
                 prev_end_offset = member_total_offset + member_byte_size
                 member_typename = member_type.GetName()
                 if member.IsBitfield():
                     print '%+4u <%3u> %s%s:%u %s;' % (member_total_offset, member_byte_size, '    ' * (depth + 1), member_typename, member.GetBitfieldSizeInBits(), member_name)
                 else:
                     print '%+4u <%3u> %s%s %s;' % (member_total_offset, member_byte_size, '    ' * (depth + 1), member_typename, member_name)

         if prev_end_offset < byte_size:
             last_member_padding = byte_size - prev_end_offset
             print '%+4u <%3u> %s<PADDING>' % (prev_end_offset, last_member_padding, '    ' * (depth + 1))
             padding += last_member_padding
     else:
         if type.IsPolymorphicClass():
             ptr_size = target.GetAddressByteSize()
             print '%+4u <%3u> %s__vtbl_ptr_type * _vptr;' % (prev_end_offset, ptr_size, '    ' * (depth + 1))
             prev_end_offset = ptr_size
         prev_end_offset = base_offset + byte_size

     return (prev_end_offset, padding)

 def get_first_file_architecture(framework_path):
     p = re.compile('shared library +(\w+)$')
     file_result = subprocess.check_output(["file", framework_path]).split('\n')
     arches = []
     for line in file_result:
         match = p.search(line)
         if match:
             arches.append(match.group(1));

     if len(arches) > 1:
         print 'Found architectures %s, using %s' % (arches, arches[0])

     if len(arches) > 0:
         return arches[0]

     return lldb.LLDB_ARCH_DEFAULT

 def dump_class(framework_path, classname, architecture):
     debugger = lldb.SBDebugger.Create()
     debugger.SetAsync(False)
     if not architecture:
         architecture = get_first_file_architecture(framework_path)

     target = debugger.CreateTargetWithFileAndArch(framework_path, architecture)
     if not target:
         print "Failed to make target for " + framework_path;
         sys.exit(1)

     module = target.GetModuleAtIndex(0)
     if not module:
         print "Failed to get first module in " + framework_path;
         sys.exit(1)

     types = module.FindTypes(classname)
     if types.GetSize():
         print 'Found %u types matching "%s" in "%s" for %s' % (len(types), classname, module.file, architecture)
         for type in types:
             verify_type(target, type)
     else:
         print 'error: no type matches "%s" in "%s"' % (classname, module.file)

     lldb.SBDebugger.Destroy(debugger)

 def main():
     parser = argparse.ArgumentParser(description='Dumps the in-memory layout of the given class or classes, showing padding holes.')
     parser.add_argument('framework', metavar='framework',
         help='name of the framework containing the class (e.g. "WebCore")')
     parser.add_argument('classname', metavar='classname',
         help='name of the class or struct to dump')

     parser.add_argument('-b', '--build-directory', dest='build_directory', action='store',
         help='Path to the directory under which build files are kept (should not include configuration)')

     parser.add_argument('-c', '--configuration', dest='config', action='store',
         help='Configuration (Debug or Release)')

     parser.add_argument('-a', '--architecture', dest='arch', action='store',
         help='Architecture (i386, x86_64, armv7, armv7s, arm64). Uses the first architecture listed by \'file\' by default')

     args = parser.parse_args()
     build_dir = webkit_build_dir()

     if args.config == None:
         args.config = "Release"

     if not args.build_directory == None:
         build_dir = args.build_directory

     target_path = os.path.join(build_dir, args.config, args.framework + ".framework", args.framework);
     import_lldb()
     dump_class(target_path, args.classname, args.arch)

 if __name__ == "__main__":
     main()
	#!/usr/bin/env python

	# Copyright (C) 2011-2015 Apple 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:
	# 1. Redistributions of source code must retain the above copyright
	# notice, this list of conditions and the following disclaimer.
	# 2. 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.
	#
	# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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.

	import re
	import sys
	import getopt
	import argparse
	import os
	import subprocess
	from sets import Set


	framework = "WebCore"
	build_directory = ""
	config = "Release"
	arch = None

	def webkit_build_dir():
	scriptpath = os.path.dirname(os.path.realpath(__file__))
	return subprocess.check_output([os.path.join(scriptpath, "webkit-build-directory"), "--top-level"]).strip()

	def developer_dir():
	return subprocess.check_output(["xcode-select", "--print-path"])

	def import_lldb():
	xcode_contents_path = os.path.split(developer_dir())[0]
	lldb_framework_path = os.path.join(xcode_contents_path, "SharedFrameworks", "LLDB.framework", "Resources", "Python")
	sys.path.append(lldb_framework_path)

	LLDB_MODULE_NAME = "lldb"
	try:
	globals()[LLDB_MODULE_NAME] = __import__(LLDB_MODULE_NAME)
	except ImportError:
	print "Failed to import {} from {}".format(LLDB_MODULE_NAME, lldb_framework_path)
	sys.exit(1)

	def verify_type(target, type):
	typename = type.GetName()
	seenOffset = Set()
	(end_offset, padding) = verify_type_recursive(target, type, None, 0, 0, 0, seenOffset)
	byte_size = type.GetByteSize()
	print 'Total byte size: %u' % (byte_size)
	print 'Total pad bytes: %u' % (padding)
	if padding > 0:
	print 'Padding percentage: %2.2f %%' % ((float(padding) / float(byte_size)) * 100.0)
	print

	def verify_type_recursive(target, type, member_name, depth, base_offset, padding, seenOffset):
	prev_end_offset = base_offset
	typename = type.GetName()
	byte_size = type.GetByteSize()
	if member_name and member_name != typename:
	print '%+4u <%3u> %s%s %s;' % (base_offset, byte_size, ' ' * depth, typename, member_name)
	else:
	print '%+4u {%3u} %s%s' % (base_offset, byte_size, ' ' * depth, typename)

	members = type.members
	if members:
	for member_idx, member in enumerate(members):
	member_type = member.GetType()
	member_canonical_type = member_type.GetCanonicalType()
	member_type_class = member_canonical_type.GetTypeClass()
	member_name = member.GetName()
	member_offset = member.GetOffsetInBytes()
	member_total_offset = member_offset + base_offset
	member_byte_size = member_type.GetByteSize()
	member_is_class_or_struct = False

	if (member_offset, member_name) in seenOffset:
	continue
	seenOffset.add((member_offset, member_name))

	if member_type_class == lldb.eTypeClassStruct or member_type_class == lldb.eTypeClassClass:
	member_is_class_or_struct = True
	if member_idx == 0 and member_offset == target.GetAddressByteSize() and type.IsPolymorphicClass():
	ptr_size = target.GetAddressByteSize()
	print '%+4u <%3u> %s__vtbl_ptr_type * _vptr;' % (prev_end_offset, ptr_size, ' ' * (depth + 1))
	prev_end_offset = ptr_size
	else:
	if prev_end_offset < member_total_offset:
	member_padding = member_total_offset - prev_end_offset
	padding = padding + member_padding
	print '%+4u <%3u> %s<PADDING>' % (prev_end_offset, member_padding, ' ' * (depth + 1))

	if member_is_class_or_struct:
	(prev_end_offset, padding) = verify_type_recursive(target, member_canonical_type, member_name, depth + 1, member_total_offset, padding, seenOffset)
	else:
	prev_end_offset = member_total_offset + member_byte_size
	member_typename = member_type.GetName()
	if member.IsBitfield():
	print '%+4u <%3u> %s%s:%u %s;' % (member_total_offset, member_byte_size, ' ' * (depth + 1), member_typename, member.GetBitfieldSizeInBits(), member_name)
	else:
	print '%+4u <%3u> %s%s %s;' % (member_total_offset, member_byte_size, ' ' * (depth + 1), member_typename, member_name)

	if prev_end_offset < byte_size:
	last_member_padding = byte_size - prev_end_offset
	print '%+4u <%3u> %s<PADDING>' % (prev_end_offset, last_member_padding, ' ' * (depth + 1))
	padding += last_member_padding
	else:
	if type.IsPolymorphicClass():
	ptr_size = target.GetAddressByteSize()
	print '%+4u <%3u> %s__vtbl_ptr_type * _vptr;' % (prev_end_offset, ptr_size, ' ' * (depth + 1))
	prev_end_offset = ptr_size
	prev_end_offset = base_offset + byte_size

	return (prev_end_offset, padding)

	def get_first_file_architecture(framework_path):
	p = re.compile('shared library +(\w+)$')
	file_result = subprocess.check_output(["file", framework_path]).split('\n')
	arches = []
	for line in file_result:
	match = p.search(line)
	if match:
	arches.append(match.group(1));

	if len(arches) > 1:
	print 'Found architectures %s, using %s' % (arches, arches[0])

	if len(arches) > 0:
	return arches[0]

	return lldb.LLDB_ARCH_DEFAULT

	def dump_class(framework_path, classname, architecture):
	debugger = lldb.SBDebugger.Create()
	debugger.SetAsync(False)
	if not architecture:
	architecture = get_first_file_architecture(framework_path)

	target = debugger.CreateTargetWithFileAndArch(framework_path, architecture)
	if not target:
	print "Failed to make target for " + framework_path;
	sys.exit(1)

	module = target.GetModuleAtIndex(0)
	if not module:
	print "Failed to get first module in " + framework_path;
	sys.exit(1)

	types = module.FindTypes(classname)
	if types.GetSize():
	print 'Found %u types matching "%s" in "%s" for %s' % (len(types), classname, module.file, architecture)
	for type in types:
	verify_type(target, type)
	else:
	print 'error: no type matches "%s" in "%s"' % (classname, module.file)

	lldb.SBDebugger.Destroy(debugger)

	def main():
	parser = argparse.ArgumentParser(description='Dumps the in-memory layout of the given class or classes, showing padding holes.')
	parser.add_argument('framework', metavar='framework',
	help='name of the framework containing the class (e.g. "WebCore")')
	parser.add_argument('classname', metavar='classname',
	help='name of the class or struct to dump')

	parser.add_argument('-b', '--build-directory', dest='build_directory', action='store',
	help='Path to the directory under which build files are kept (should not include configuration)')

	parser.add_argument('-c', '--configuration', dest='config', action='store',
	help='Configuration (Debug or Release)')

	parser.add_argument('-a', '--architecture', dest='arch', action='store',
	help='Architecture (i386, x86_64, armv7, armv7s, arm64). Uses the first architecture listed by \'file\' by default')

	args = parser.parse_args()
	build_dir = webkit_build_dir()

	if args.config == None:
	args.config = "Release"

	if not args.build_directory == None:
	build_dir = args.build_directory

	target_path = os.path.join(build_dir, args.config, args.framework + ".framework", args.framework);
	import_lldb()
	dump_class(target_path, args.classname, args.arch)

	if __name__ == "__main__":
	main()