Dropping in software construction toolkit.

site_scons/site_tools/seven_zip.py

Index: site_scons/site_tools/seven_zip.py
===================================================================
--- site_scons/site_tools/seven_zip.py	(revision 0)
+++ site_scons/site_tools/seven_zip.py	(revision 0)
@@ -0,0 +1,145 @@
+#!/usr/bin/python2.4
+# Copyright 2008, 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.
+
+
+"""SCons tool for 7zip."""
+
+
+import os
+import shutil
+import subprocess
+import tempfile
+import SCons.Script
+
+
+def SevenZipGetFiles(env, source):
+  """SCons emitter for 7zip extract.
+
+  Examines the source 7z archive to determine the list of files which will be
+  created by extract/unzip operation.
+  Args:
+    env: The SCons environment to get the 7zip command line from.
+    source: The 7zip archive to examine.
+  Returns:
+    The list of filenames in the archive.
+  """
+  # Expand the command to list archive contents.
+  cmd = env.subst('$SEVEN_ZIP l "%s"' % source)
+  # Run it and capture output.
+  output = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0]
+  # Strip off 7-line header and 3-line trailer from 7zip output.
+  lines = output.split('\r\n')[7:-3]
+  # Trim out just the files and their names.
+  files = [i[53:] for i in lines if i[20] != 'D']
+  return files
+
+
+def SevenZipEmitter(target, source, env):
+  """An emitter that decides what nodes are vented from a 7zip archive.
+
+  Args:
+    target: The target directory node.
+    source: The source archive node.
+    env: The environment in which the emit takes place.
+  Returns:
+    The pair (target, source) which lists the emitted targets and sources.
+  """
+  # Remember out dir for later.
+  env['SEVEN_ZIP_OUT_DIR'] = target[0].dir
+  # Get out contents
+  files = SevenZipGetFiles(env, env.subst('$SOURCE', source=source))
+  # Extract a layer deeper if there is only one, and it extension is 7z.
+  if env.get('SEVEN_ZIP_PEEL_LAYERS', False):
+    assert len(files) == 1 and os.path.splitext(files[0])[1] == '.7z'
+    # Create a temporary directory.
+    tmp_dir = tempfile.mkdtemp()
+    # Expand the command to extract the archive to a temporary location.
+    cmd = env.subst('$SEVEN_ZIP x $SOURCE -o"%s"' % tmp_dir, source=source[0])
+    # Run it and swallow output.
+    subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()
+    # Get contents.
+    inner_files = SevenZipGetFiles(env, os.path.join(tmp_dir, files[0]))
+    # Make into file nodes.
+    inner_files = [target[0].dir.File(i) for i in inner_files]
+    # Delete temp_dir.
+    shutil.rmtree(tmp_dir)
+    # Decide where to extra working file to.
+    working_file = env.Dir(target[0].dir.abspath +
+                           '.7zip_extract').File(files[0])
+    # Combine everything.
+    files = [working_file] + inner_files
+  else:
+    # Make into file nodes.
+    files = [target[0].dir.File(i) for i in files]
+  # Return files as actual target.
+  return (files, source)
+
+
+def SevenZipGenerator(source, target, env, for_signature):
+  """The generator function which decides how to extract a file."""
+
+  # Silence lint.
+  source = source
+  target = target
+  for_signature = for_signature
+
+  if env.get('SEVEN_ZIP_PEEL_LAYERS', False):
+    return [SCons.Script.Delete('$SEVEN_ZIP_OUT_DIR'),
+            '$SEVEN_ZIP x $SOURCE -o"${TARGET.dir}"',
+            '$SEVEN_ZIP x $TARGET -o"$SEVEN_ZIP_OUT_DIR"']
+  else:
+    return [SCons.Script.Delete('$SEVEN_ZIP_OUT_DIR'),
+            '$SEVEN_ZIP x $SOURCE -o"$SEVEN_ZIP_OUT_DIR"']
+
+
+def generate(env):
+  # NOTE: SCons requires the use of this name, which fails gpylint.
+  """SCons entry point for this tool."""
+
+  env.Replace(
+      SEVEN_ZIP='$SEVEN_ZIP_DIR/7za.exe',
+      SEVEN_ZIP_ARCHIVE_OPTIONS = ['-t7z', '-mx0'],
+      SEVEN_ZIP_COMPRESS_OPTIONS = ['-t7z', '-mx9'],
+  )
+
+  b = SCons.Script.Builder(generator=SevenZipGenerator,
+                           emitter=SevenZipEmitter)
+  env['BUILDERS']['Extract7zip'] = b
+
+  b = SCons.Script.Builder(
+      action=('cd $SOURCE && '
+              '$SEVEN_ZIP a $SEVEN_ZIP_ARCHIVE_OPTIONS ${TARGET.abspath} ./'))
+  env['BUILDERS']['Archive7zip'] = b
+
+  b = SCons.Script.Builder(
+      action=('cd ${SOURCE.dir} && '
+              '$SEVEN_ZIP a $SEVEN_ZIP_COMPRESS_OPTIONS '
+              '${TARGET.abspath} ${SOURCE.file}'))
+  env['BUILDERS']['Compress7zip'] = b