Improve the toolchains-hash calculation.

I often ends up with a corrupt toolchain because I've used Windbg and there's now a bunch of PDB files in win_sdk/Debuggers/sym/... , I think that it's safe to ignore these files (the original package doesn't contain any of these files).

It's also useful to have more details about which files are missing and or which ones shouldn't be here when we get an invalid toolchain hash.

Finally, if you the hash of a toolchain doesn't correspond to the name of its root directory then it should be removed.

Review-Url: https://codereview.chromium.org/1974453003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300557 0039d316-1c4b-4281-b951-d872f2087c98

win_toolchain/get_toolchain_if_necessary.py

@@ -72,11 +72,19 @@ def GetFileList(root):
   assert not os.path.isabs(root)
   assert os.path.normpath(root) == root
   file_list = []
+  # Ignore WER ReportQueue entries that vctip/cl leave in the bin dir if/when
+  # they crash. Also ignores the content of the win_sdk/debuggers/x(86|64)/sym/
+  # directories as this is just the temporarily location that Windbg might use
+  # to store the symbol files.
+  ignored_directories = ['wer\\reportqueue',
+                         'win_sdk\\debuggers\\x86\\sym\\',
+                         'win_sdk\\debuggers\\x64\\sym\\']
   for base, _, files in os.walk(root):
-    paths = [os.path.join(base, f) for f in files]
-    # Ignore WER ReportQueue entries that vctip/cl leave in the bin dir if/when
-    # they crash.
-    file_list.extend(x.lower() for x in paths if 'WER\\ReportQueue' not in x)
+    paths = [os.path.join(base, f).lower() for f in files]
+    for p in paths:
+      if any(ignored_dir in p for ignored_dir in ignored_directories):
+        continue
+      file_list.append(p)
   return sorted(file_list, key=lambda s: s.replace('/', '\\'))
 
 
@@ -119,6 +127,25 @@ def CalculateHash(root, expected_hash):
           disk != vc_dir and os.path.getmtime(disk) != cached[1]):
         matches = False
         break
+  elif os.path.exists(timestamps_file):
+    # Print some information about the extra/missing files. Don't do this if we
+    # don't have a timestamp file, as all the files will be considered as
+    # missing.
+    timestamps_data_files = []
+    for f in timestamps_data['files']:
+      timestamps_data_files.append(f[0])
+    missing_files = [f for f in timestamps_data_files if f not in file_list]
+    if len(missing_files):
+      print ('Some files are missing from the %s version of the toolchain:' %
+             expected_hash)
+      for f in missing_files:
+        print '\t%s' % f
+    extra_files = [f for f in file_list if f not in timestamps_data_files]
+    if len(extra_files):
+      print ('There\'s some extra files in the %s version of the toolchain:' %
+             expected_hash)
+      for f in extra_files:
+        print '\t%s' % f
   if matches:
     return timestamps_data['sha1']
 
@@ -137,14 +164,22 @@ def CalculateHash(root, expected_hash):
   return digest.hexdigest()
 
 
-def CalculateToolchainHashes(root):
+def CalculateToolchainHashes(root, remove_corrupt_toolchains):
   """Calculate the hash of the different toolchains installed in the |root|
   directory."""
   hashes = []
   dir_list = [
       d for d in os.listdir(root) if os.path.isdir(os.path.join(root, d))]
   for d in dir_list:
-    hashes.append(CalculateHash(root, d))
+    toolchain_hash = CalculateHash(root, d)
+    if toolchain_hash != d:
+      print ('The hash of a version of the toolchain has an unexpected value ('
+             '%s instead of %s)%s.' % (toolchain_hash, d,
+             ', removing it' if remove_corrupt_toolchains else ''))
+      if remove_corrupt_toolchains:
+        RemoveToolchain(root, d, True)
+    else:
+      hashes.append(toolchain_hash)
   return hashes
 
 
@@ -425,7 +460,7 @@ def main():
   # Typically this script is only run when the .sha1 one file is updated, but
   # directly calling "gclient runhooks" will also run it, so we cache
   # based on timestamps to make that case fast.
-  current_hashes = CalculateToolchainHashes(target_dir)
+  current_hashes = CalculateToolchainHashes(target_dir, True)
   if desired_hash not in current_hashes:
     should_use_gs = False
     if (HaveSrcInternalAccess() or
@@ -479,7 +514,7 @@ def main():
     json.dump(data, f)
 
   if got_new_toolchain:
-    current_hashes = CalculateToolchainHashes(target_dir)
+    current_hashes = CalculateToolchainHashes(target_dir, False)
     if desired_hash not in current_hashes:
       print >> sys.stderr, (
           'Got wrong hash after pulling a new toolchain. '