Add the beginnings of scripts to produce SDKs.

sdk_build/pylib/git.py

Index: sdk_build/pylib/git.py
diff --git a/sdk_build/pylib/git.py b/sdk_build/pylib/git.py
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index 0000000000000000000000000000000000000000..fa09880cdec27e773ced8e52086b9452ca7b5f00
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+++ b/sdk_build/pylib/git.py
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+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Git support functions."""
+
+
+from errors import FatalError
+import fnmatch
+import os.path
+import subprocess
+
+
+def Git(subcommand, *args):
+  """Runs "git <subcommand> <args...>" and returns the output, including
+  standard error. Raises |OSError| if it fails to run git at all and
+  |subprocess.CalledProcessError| if the command returns failure (nonzero)."""
+
+  return subprocess.check_output(
+      ('git', subcommand) + args, stderr=subprocess.STDOUT)
+
+
+def SanityCheckGit():
+  """Does a sanity check that git is available and the current working directory
+  is in a git repository (exits with an error message on failure)."""
+
+  try:
+    Git("status")
+  except OSError:
+    FatalError("failed to run git -- is it in your PATH?")
+  except subprocess.CalledProcessError:
+    FatalError("\"git status\" failed -- is %s in a git repository?" %
+        os.getcwd())
+
+
+def IsGitTreeDirty():
+  """Checks if the tree looks dirty (returning true if it is)."""
+
+  try:
+    Git("diff-index", "--quiet", "HEAD")
+  except subprocess.CalledProcessError:
+    return True
+  return False
+
+
+def GitLsFiles(path, recursive=True, exclude_file_patterns=None,
+              exclude_path_patterns=None):
+  """Returns a list of files under the given path (the filenames will include
+  the full path). If |recursive| is true (the default), then this list will
+  include all files (recursively); if not, it will only include the files "at"
+  the exact path. |exclude_file_patterns| may be a list of shell-style wildcards
+  of filenames to exclude. Similarly, |exclude_path_patterns| may be a list of
+  shell-style wildcards of paths to exclude (note: to make it easier to match
+  subtrees, a trailing '/' is added to the path for matching purposes)."""
+
+  # Files are "null-terminated". This results in an extra empty string at the
+  # end. "Luckily", in the empty case, we also get an empty string.
+  result = Git("ls-files", "-z", path).split("\0")[:-1]
+  if not recursive:
+    result = [f for f in result if os.path.dirname(f) == path]
+  if exclude_file_patterns:
+    for p in exclude_file_patterns:
+      result = [f for f in result
+                if not fnmatch.fnmatch(os.path.basename(f), p)]
+  if exclude_path_patterns:
+    for p in exclude_path_patterns:
+      result = [f for f in result
+                if not fnmatch.fnmatch(os.path.dirname(f) + "/", p)]
+  return result