#!/usr/bin/env python
# Copyright (c) 2012 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Generator for Pnacl Shim functions that bridges the calling conventions
between GCC and PNaCl. """
from datetime import datetime
import difflib
import glob
import os
import sys
from idl_c_proto import CGen
from idl_gen_wrapper import Interface, WrapperGen
from idl_log import ErrOut, InfoOut, WarnOut
from idl_option import GetOption, Option, ParseOptions
from idl_parser import ParseFiles
Option('pnaclshim', 'Name of the pnacl shim file.',
default='temp_pnacl_shim.c')
Option('disable_pnacl_opt', 'Turn off optimization of pnacl shim.')
class PnaclGen(WrapperGen):
"""PnaclGen generates shim code to bridge the Gcc ABI with PNaCl.
This subclass of WrapperGenerator takes the IDL sources and
generates shim methods for bridging the calling conventions between GCC
and PNaCl (LLVM). Some of the PPAPI methods do not need shimming, so
this will also detect those situations and provide direct access to the
original PPAPI methods (rather than the shim methods).
"""
def __init__(self):
WrapperGen.__init__(self,
'Pnacl',
'Pnacl Shim Gen',
'pnacl',
'Generate the PNaCl shim.')
self.cgen = CGen()
self._skip_opt = False
############################################################
def OwnHeaderFile(self):
"""Return the header file that specifies the API of this wrapper.
We do not generate the header files. """
return 'ppapi/generators/pnacl_shim.h'
def InterfaceVersionNeedsWrapping(self, iface, version):
"""Return true if the interface+version has ANY methods that
need wrapping.
"""
if self._skip_opt:
return True
if iface.GetName().endswith('Trusted'):
return False
for member in iface.GetListOf('Member'):
release = member.GetRelease(version)
if self.MemberNeedsWrapping(member, release):
return True
return False
def MemberNeedsWrapping(self, member, release):
"""Return true if a particular member function at a particular
release needs wrapping.
"""
if self._skip_opt:
return True
if not member.InReleases([release]):
return False
ret, name, array, args_spec = self.cgen.GetComponents(member,
release,
'store')
return self.TypeNeedsWrapping(ret, []) or self.ArgsNeedWrapping(args_spec)
def ArgsNeedWrapping(self, args):
"""Return true if any parameter in the list needs wrapping.
"""
for arg in args:
(type_str, name, array_dims, more_args) = arg
if self.TypeNeedsWrapping(type_str, array_dims):
return True
return False
def TypeNeedsWrapping(self, type_node, array_dims):
"""Return true if a parameter type needs wrapping.
Currently, this is true for byval aggregates.
"""
is_aggregate = type_node.startswith('struct') or \
type_node.startswith('union')
is_reference = (type_node.find('*') != -1 or array_dims != [])
return is_aggregate and not is_reference
############################################################
def ConvertByValueReturnType(self, ret, args_spec):
if self.TypeNeedsWrapping(ret, array_dims=[]):
args_spec = [(ret, '_struct_result', [], None)] + args_spec
ret2 = 'void'
wrap_return = True
else:
ret2 = ret
wrap_return = False
return wrap_return, ret2, args_spec
def ConvertByValueArguments(self, args_spec):
args = []
for type_str, name, array_dims, more_args in args_spec:
if self.TypeNeedsWrapping(type_str, array_dims):
type_str += '*'
args.append((type_str, name, array_dims, more_args))
return args
def FormatArgs(self, c_operator, args_spec):
args = []
for type_str, name, array_dims, more_args in args_spec:
if self.TypeNeedsWrapping(type_str, array_dims):
args.append(c_operator + name)
else:
args.append(name)
return ', '.join(args)
def GenerateWrapperForPPBMethod(self, iface, member):
result = []
func_prefix = self.WrapperMethodPrefix(iface.node, iface.release)
ret, name, array, cspec = self.cgen.GetComponents(member,
iface.release,
'store')
wrap_return, ret2, cspec2 = self.ConvertByValueReturnType(ret, cspec)
cspec2 = self.ConvertByValueArguments(cspec2)
sig = self.cgen.Compose(ret2, name, array, cspec2,
prefix=func_prefix,
func_as_ptr=False,
include_name=True,
unsized_as_ptr=False)
result.append('static %s {\n' % sig)
result.append(' const struct %s *iface = %s.real_iface;\n' %
(iface.struct_name, self.GetWrapperInfoName(iface)))
return_prefix = ''
if wrap_return:
return_prefix = '*_struct_result = '
elif ret != 'void':
return_prefix = 'return '
result.append(' %siface->%s(%s);\n}\n\n' % (return_prefix,
member.GetName(),
self.FormatArgs('*', cspec)))
return result
def GenerateWrapperForPPPMethod(self, iface, member):
result = []
func_prefix = self.WrapperMethodPrefix(iface.node, iface.release)
sig = self.cgen.GetSignature(member, iface.release, 'store',
func_prefix, False)
result.append('static %s {\n' % sig)
result.append(' const struct %s *iface = %s.real_iface;\n' %
(iface.struct_name, self.GetWrapperInfoName(iface)))
ret, name, array, cspec = self.cgen.GetComponents(member,
iface.release,
'store')
wrap_return, ret2, cspec = self.ConvertByValueReturnType(ret, cspec)
cspec2 = self.ConvertByValueArguments(cspec)
temp_fp = self.cgen.Compose(ret2, name, array, cspec2,
prefix='temp_fp',
func_as_ptr=True,
include_name=False,
unsized_as_ptr=False)
cast = self.cgen.Compose(ret2, name, array, cspec2,
prefix='',
func_as_ptr=True,
include_name=False,
unsized_as_ptr=False)
result.append(' %s =\n ((%s)iface->%s);\n' % (temp_fp,
cast,
member.GetName()))
return_prefix = ''
if wrap_return:
result.append(' %s _struct_result;\n' % ret)
elif ret != 'void':
return_prefix = 'return '
result.append(' %stemp_fp(%s);\n' % (return_prefix,
self.FormatArgs('&', cspec)))
if wrap_return:
result.append(' return _struct_result;\n')
result.append('}\n\n')
return result
def GenerateRange(self, ast, releases, options):
"""Generate shim code for a range of releases.
"""
self._skip_opt = GetOption('disable_pnacl_opt')
self.SetOutputFile(GetOption('pnaclshim'))
return WrapperGen.GenerateRange(self, ast, releases, options)
pnaclgen = PnaclGen()
######################################################################
# Tests.
# Clean a string representing an object definition and return then string
# as a single space delimited set of tokens.
def CleanString(instr):
instr = instr.strip()
instr = instr.split()
return ' '.join(instr)
def PrintErrorDiff(old, new):
oldlines = old.split(';')
newlines = new.split(';')
d = difflib.Differ()
diff = d.compare(oldlines, newlines)
ErrOut.Log('Diff is:\n%s' % '\n'.join(diff))
def GetOldTestOutput(ast):
# Scan the top-level comments in the IDL file for comparison.
old = []
for filenode in ast.GetListOf('File'):
for node in filenode.GetChildren():
instr = node.GetOneOf('Comment')
if not instr: continue
instr.Dump()
old.append(instr.GetName())
return CleanString(''.join(old))
def TestFiles(filenames, test_releases):
ast = ParseFiles(filenames)
iface_releases = pnaclgen.DetermineInterfaces(ast, test_releases)
new_output = CleanString(pnaclgen.GenerateWrapperForMethods(
iface_releases, comments=False))
old_output = GetOldTestOutput(ast)
if new_output != old_output:
PrintErrorDiff(old_output, new_output)
ErrOut.Log('Failed pnacl generator test.')
return 1
else:
InfoOut.Log('Passed pnacl generator test.')
return 0
def Main(args):
filenames = ParseOptions(args)
test_releases = ['M13', 'M14', 'M15']
if not filenames:
idldir = os.path.split(sys.argv[0])[0]
idldir = os.path.join(idldir, 'test_gen_pnacl', '*.idl')
filenames = glob.glob(idldir)
filenames = sorted(filenames)
if GetOption('test'):
# Run the tests.
return TestFiles(filenames, test_releases)
# Otherwise, generate the output file (for potential use as golden file).
ast = ParseFiles(filenames)
return pnaclgen.GenerateRange(ast, test_releases, filenames)
if __name__ == '__main__':
retval = Main(sys.argv[1:])
sys.exit(retval)