Automatically download gnu win tools from update.py

I put a small zip (1.6MB) on GCS containing just the gnu tools
(from GNUWin32) that are required by LLVM's check-all target.
If more are needed in the future, we'll need to push a new
zip file to GCS with the new tools.  This seems better than
downloading the full 182MB gnuwin tools from the script.

BUG=578306

Review URL: https://codereview.chromium.org/1781113002

Cr-Commit-Position: refs/heads/master@{#380661}

2 files changed, 24 insertions, 12 deletions

diff --git a/tools/clang/scripts/package.py b/tools/clang/scripts/package.py
index 944acee..63ab1a9 100755
--- a/tools/clang/scripts/package.py
+++ b/tools/clang/scripts/package.py
@@ -110,13 +110,6 @@ def MaybeUpload(args, archive_name, platform):
 
 
 def main():
-  if sys.platform == 'win32':
-    try:
-      subprocess.check_output(['grep', '--help'], shell=True)
-    except subprocess.CalledProcessError:
-      print 'Add gnuwin32 to your PATH, then try again.'
-      return 1
-
   parser = argparse.ArgumentParser(description='build and package clang')
   parser.add_argument('--upload', action='store_true',
                       help='Upload the target archive to Google Cloud Storage.')
diff --git a/tools/clang/scripts/update.py b/tools/clang/scripts/update.py
index e3fa1b1..b005520 100755
--- a/tools/clang/scripts/update.py
+++ b/tools/clang/scripts/update.py
@@ -136,19 +136,19 @@ def DownloadAndUnpack(url, output_dir):
       tarfile.open(mode='r:gz', fileobj=f).extractall(path=output_dir)
 
 
-def ReadStampFile():
+def ReadStampFile(path=STAMP_FILE):
   """Return the contents of the stamp file, or '' if it doesn't exist."""
   try:
-    with open(STAMP_FILE, 'r') as f:
+    with open(path, 'r') as f:
       return f.read().rstrip()
   except IOError:
     return ''
 
 
-def WriteStampFile(s):
+def WriteStampFile(s, path=STAMP_FILE):
   """Write s to the stamp file."""
-  EnsureDirExists(os.path.dirname(STAMP_FILE))
-  with open(STAMP_FILE, 'w') as f:
+  EnsureDirExists(os.path.dirname(path))
+  with open(path, 'w') as f:
     f.write(s)
     f.write('\n')
 
@@ -305,6 +305,24 @@ def AddCMakeToPath():
   os.environ['PATH'] = cmake_dir + os.pathsep + os.environ.get('PATH', '')
 
 
+def AddGnuWinToPath():
+  """Download some GNU win tools and add them to PATH."""
+  if sys.platform != 'win32':
+    return
+
+  gnuwin_dir = os.path.join(LLVM_BUILD_TOOLS_DIR, 'gnuwin')
+  GNUWIN_VERSION = '1'
+  GNUWIN_STAMP = os.path.join(gnuwin_dir, 'stamp')
+  if ReadStampFile(GNUWIN_STAMP) == GNUWIN_VERSION:
+    print 'GNU Win tools already up to date.'
+  else:
+    zip_name = 'gnuwin-%s.zip' % GNUWIN_VERSION
+    DownloadAndUnpack(CDS_URL + '/tools/' + zip_name, LLVM_BUILD_TOOLS_DIR)
+    WriteStampFile(GNUWIN_VERSION, GNUWIN_STAMP)
+
+  os.environ['PATH'] = gnuwin_dir + os.pathsep + os.environ.get('PATH', '')
+
+
 vs_version = None
 def GetVSVersion():
   global vs_version
@@ -381,6 +399,7 @@ def UpdateClang(args):
 
   DownloadHostGcc(args)
   AddCMakeToPath()
+  AddGnuWinToPath()
 
   DeleteChromeToolsShim()