Pnacl ppapi shim generator (from IDL), based on Noel's first cut.

ppapi/generators/idl_gen_pnacl.py

+#!/usr/bin/python
+#
+# Copyright (c) 2011 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
+    self._pnacl_attribute = '__attribute__((pnaclcall))'
+
+  ############################################################
+
+  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 InterfaceNeedsWrapper(self, iface, releases):
+    """Return true if the interface has ANY methods that need wrapping.
+    """
+    if self._skip_opt:
+      return True
+    for release in iface.GetUniqueReleases(releases):
+      version = iface.GetVersion(release)
+      if self.InterfaceVersionNeedsWrapping(iface, version):
+        return True
+    return False
+
+
+  def InterfaceVersionNeedsWrapping(self, iface, version):
+    """Return true if the interface+version has ANY methods that
+    need wrapping.
+    """
+    if self._skip_opt:
+      return True
+    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 GenerateWrapperForPPBMethod(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%s {\n' % (self._pnacl_attribute, 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')
+    ret_str, args_str = self.GetReturnArgs(ret, cspec)
+    result.append('  %siface->%s(%s);\n}\n\n' % (ret_str,
+                                                 member.GetName(), args_str))
+    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)))
+    temp_fp = self.cgen.GetSignature(member, iface.release, 'return',
+                                     'temp_fp',
+                                     func_as_ptr=True,
+                                     ptr_prefix=self._pnacl_attribute + ' ',
+                                     include_name=False)
+    cast = self.cgen.GetSignature(member, iface.release, 'return',
+                                  prefix='',
+                                  func_as_ptr=True,
+                                  ptr_prefix=self._pnacl_attribute + ' ',
+                                  include_name=False)
+    result.append('  %s = ((%s)iface->%s);\n' % (temp_fp,
+                                                 cast,
+                                                 member.GetName()))
+    ret, name, array, cspec = self.cgen.GetComponents(member,
+                                                      iface.release,
+                                                      'store')
+    ret_str, args_str = self.GetReturnArgs(ret, cspec)
+    result.append('  %stemp_fp(%s);\n}\n\n' % (ret_str, args_str))
+    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)