third_party/WebKit/Source/build/scripts/rule_bison.py

   1 #!/usr/bin/python
   2 #
   3 # Copyright (C) 2009 Google Inc. All rights reserved.
   4 #
   5 # Redistribution and use in source and binary forms, with or without
   6 # modification, are permitted provided that the following conditions are
   7 # met:
   8 #
   9 #     * Redistributions of source code must retain the above copyright
  10 # notice, this list of conditions and the following disclaimer.
  11 #     * Redistributions in binary form must reproduce the above
  12 # copyright notice, this list of conditions and the following disclaimer
  13 # in the documentation and/or other materials provided with the
  14 # distribution.
  15 #     * Neither the name of Google Inc. nor the names of its
  16 # contributors may be used to endorse or promote products derived from
  17 # this software without specific prior written permission.
  18 #
  19 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30 #
  31 # Copyright (c) 2009 The Chromium Authors. All rights reserved.
  32 # Use of this source code is governed by a BSD-style license that can be
  33 # found in the LICENSE file.
  34
  35 # usage: rule_bison.py INPUT_FILE OUTPUT_DIR [BISON_EXE]
  36 # INPUT_FILE is a path to either XPathGrammar.y.
  37 # OUTPUT_DIR is where the bison-generated .cpp and .h files should be placed.
  38
  39 import errno
  40 import os
  41 import os.path
  42 import subprocess
  43 import sys
  44
  45 assert len(sys.argv) == 3 or len(sys.argv) == 4
  46
  47 inputFile = sys.argv[1]
  48 outputDir = sys.argv[2]
  49 bisonExe = 'bison'
  50 if len(sys.argv) > 3:
  51     bisonExe = sys.argv[3]
  52
  53 pathToBison = os.path.split(bisonExe)[0]
  54 if pathToBison:
  55     # Make sure this path is in the path so that it can find its auxiliary
  56     # binaries (in particular, m4). To avoid other 'm4's being found, insert
  57     # at head, rather than tail.
  58     os.environ['PATH'] = pathToBison + os.pathsep + os.environ['PATH']
  59
  60 inputName = os.path.basename(inputFile)
  61 assert inputName == 'XPathGrammar.y'
  62 prefix = {'XPathGrammar.y': 'xpathyy'}[inputName]
  63
  64 (inputRoot, inputExt) = os.path.splitext(inputName)
  65
  66 # The generated .h will be in a different location depending on the bison
  67 # version.
  68 outputHTries = [
  69     os.path.join(outputDir, inputRoot + '.cpp.h'),
  70     os.path.join(outputDir, inputRoot + '.hpp'),
  71 ]
  72
  73 for outputHTry in outputHTries:
  74     try:
  75         os.unlink(outputHTry)
  76     except OSError, e:
  77         if e.errno != errno.ENOENT:
  78             raise
  79
  80 outputCpp = os.path.join(outputDir, inputRoot + '.cpp')
  81
  82 returnCode = subprocess.call([bisonExe, '-d', '-p', prefix, inputFile, '-o', outputCpp])
  83 assert returnCode == 0
  84
  85 # Find the name that bison used for the generated header file.
  86 outputHTmp = None
  87 for outputHTry in outputHTries:
  88     try:
  89         os.stat(outputHTry)
  90         outputHTmp = outputHTry
  91         break
  92     except OSError, e:
  93         if e.errno != errno.ENOENT:
  94             raise
  95
  96 assert outputHTmp != None
  97
  98 # Read the header file in under the generated name and remove it.
  99 outputHFile = open(outputHTmp)
 100 outputHContents = outputHFile.read()
 101 outputHFile.close()
 102 os.unlink(outputHTmp)
 103
 104 # Rewrite the generated header with #include guards.
 105 outputH = os.path.join(outputDir, inputRoot + '.h')
 106
 107 outputHFile = open(outputH, 'w')
 108 print >>outputHFile, '#ifndef %sH' % inputRoot
 109 print >>outputHFile, '#define %sH' % inputRoot
 110 print >>outputHFile, outputHContents
 111 print >>outputHFile, '#endif'
 112 outputHFile.close()