Pull and build shaderc rather than use checked in lib/header

tools/build_shaderc.py

+#!/usr/bin/python
+
+# Copyright 2016 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+
+"""
+Script to build the shaderc library.
+"""
+
+import argparse
+import os
+import shlex
+import shutil
+import subprocess
+import sys
+
+def main():
+  parser = argparse.ArgumentParser(description='Builds shaderc')
+  parser.add_argument('-s', '--src-dir', required=True, help=
+      'path to shaderc source')
+  parser.add_argument('-t', '--build-type', required=True, help=
+      'Either Release or Debug')
+  parser.add_argument('-a', '--arch-type', required=True, help=
+      'Either x86 or x86_64')
+  parser.add_argument('-o', '--output-dir', required=True, help=
+      'Directory for cmake build')
+  parser.add_argument('-p', '--project_type', required=True, help=
+      'Project type to use. Must be "ninja", "MSVS2013", or "MSVS2015"')
+  args = parser.parse_args()
+
+  args.src_dir = os.path.abspath(args.src_dir)
+  args.output_dir = os.path.abspath(args.output_dir)
+
+  if not os.path.isdir(args.src_dir):
+    sys.exit(args.src_dir + ' is not a directory.')
+    
+  if args.build_type != 'Debug' and args.build_type != 'Release':
+    sys.exit('Invalid build type: ' + args.build_type);
+
+  if args.arch_type == 'x86':
+    vs_arch = ''
+  elif args.arch_type == 'x86_64':
+    vs_arch = ' Win64'
+  else:
+    sys.exit('Invalid arch type: ' + args.arch_type);
+
+  if args.project_type == 'ninja':
+    generator = 'Ninja'
+  elif args.project_type == 'MSVS2013':
+    generator = 'Visual Studio 12 2013' + vs_arch
+  elif args.project_type == "MSVS2015":
+    generator = 'Visual Studio 14 2015' + vs_arch
+  else:
+    sys.exit('Invalid project type: ' + args.project_type);
+
+  if not os.path.isdir(args.output_dir):
+    try:
+      os.makedirs(args.output_dir)
+    except os.error:
+      sys.exit('Error creating output dir ' + args.output_dir)
+
+  try:
+    subprocess.check_call(['cmake', '-G', generator,
+        '-DSPIRV_SKIP_EXECUTABLES=ON', args.src_dir], cwd=args.output_dir)
+  except subprocess.CalledProcessError as error:
+    sys.exit('Error (ret code: {code}) calling "{cmd}" in {dir}'.format(
+        code = error.returncode, cmd = error.cmd, dir = args.src_dir))
+
+  try:
+    subprocess.check_call(['cmake', '--build', args.output_dir, '--config',
+        args.build_type], cwd=args.output_dir)
+  except subprocess.CalledProcessError as error:
+    sys.exit('Error (ret code: {code}) calling "{cmd}" in {dir}'.format(
+        code = error.returncode, cmd = error.cmd, dir = args.src_dir))
+
+if __name__ == '__main__':
+  main()
+