Start libc++ python cleanup and consolidation.

Libc++ frequently creates and uses utilities written in python.
Currently there are python modules under both libcxx/test and
libcxx/util. My goal with these changes is to consolidate them
into a single package under libcxx/utils/libcxx.

llvm-svn: 294644
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 0b37f209bf2aaf9b06276a0c40d1c29b5d6bfe89
diff --git a/utils/sym_extract.py b/utils/sym_extract.py
new file mode 100755
index 0000000..0d9d2ee
--- /dev/null
+++ b/utils/sym_extract.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+#===----------------------------------------------------------------------===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is dual licensed under the MIT and the University of Illinois Open
+# Source Licenses. See LICENSE.TXT for details.
+#
+#===----------------------------------------------------------------------===##
+"""
+sym_extract - Extract and output a list of symbols from a shared library.
+"""
+from argparse import ArgumentParser
+from libcxx.sym_check import extract, util
+
+
+def main():
+    parser = ArgumentParser(
+        description='Extract a list of symbols from a shared library.')
+    parser.add_argument('library', metavar='shared-lib', type=str,
+                        help='The library to extract symbols from')
+    parser.add_argument('-o', '--output', dest='output',
+                        help='The output file. stdout is used if not given',
+                        type=str, action='store', default=None)
+    parser.add_argument('--names-only', dest='names_only',
+                        help='Output only the name of the symbol',
+                        action='store_true', default=False)
+    parser.add_argument('--only-stdlib-symbols', dest='only_stdlib',
+                        help="Filter all symbols not related to the stdlib",
+                        action='store_true', default=False)
+    args = parser.parse_args()
+    if args.output is not None:
+        print('Extracting symbols from %s to %s.'
+              % (args.library, args.output))
+    syms = extract.extract_symbols(args.library)
+    if args.only_stdlib:
+        syms, other_syms = util.filter_stdlib_symbols(syms)
+    util.write_syms(syms, out=args.output, names_only=args.names_only)
+
+
+if __name__ == '__main__':
+    main()