Fix relative/absolute path handling in checkdeps.py

Currently checkdeps.py fails if you specify a start dir and a *relative* path for root, such as:
tools/checkdeps/checkdeps.py --root third_party/WebKit Source/bindings
(Exact error is a stack overflow, due to infinite recursion on /)
This is because it makes the start dir absolute, but doesn't make the root dir absolute.

Simple fix, by making the root dir absolute.
Also checks that directory to check is actually a subdirectory of root, which otherwise has the same stack overflow error.

R=joi
BUG=365190

Review URL: https://codereview.chromium.org/244673002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@265566 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 9 insertions, 4 deletions

diff --git a/tools/checkdeps/checkdeps.py b/tools/checkdeps/checkdeps.py
index 3789b0e..6e815c0 100755
--- a/tools/checkdeps/checkdeps.py
+++ b/tools/checkdeps/checkdeps.py
@@ -195,21 +195,26 @@ def main():
                              verbose=options.verbose,
                              ignore_temp_rules=options.ignore_temp_rules,
                              skip_tests=options.skip_tests)
+  base_directory = deps_checker.base_directory  # Default if needed, normalized
 
   # Figure out which directory we have to check.
-  start_dir = deps_checker.base_directory
+  start_dir = base_directory
   if len(args) == 1:
     # Directory specified. Start here. It's supposed to be relative to the
     # base directory.
-    start_dir = os.path.abspath(
-        os.path.join(deps_checker.base_directory, args[0]))
+    start_dir = os.path.abspath(os.path.join(base_directory, args[0]))
   elif len(args) >= 2 or (options.generate_temp_rules and
                           options.count_violations):
     # More than one argument, or incompatible flags, we don't handle this.
     PrintUsage()
     return 1
 
-  print 'Using base directory:', deps_checker.base_directory
+  if not start_dir.startswith(deps_checker.base_directory):
+    print 'Directory to check must be a subdirectory of the base directory,'
+    print 'but %s is not a subdirectory of %s' % (start_dir, base_directory)
+    return 1
+
+  print 'Using base directory:', base_directory
   print 'Checking:', start_dir
 
   if options.generate_temp_rules: