Add a Python script to change what version of Clang is used by Xcode for static analysis (and ONLY static analysis).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95569 91177308-0d34-0410-b5e6-96231b3b80d8

tools/scan-build/set-xcode-analyzer

@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+import os
+import sys
+import re
+import tempfile
+import shutil
+import stat
+
+def FindClangSpecs(path):
+  for root, dirs, files in os.walk(path):
+    for f in files:
+      if f.endswith(".xcspec") and f.startswith("Clang LLVM"):
+        yield os.path.join(root, f)
+
+def ModifySpec(path, pathToChecker):
+  print "Updating:", path
+  t = tempfile.NamedTemporaryFile(delete=False)
+  foundAnalyzer = False
+  with open(path) as f:
+    for line in f:
+      if not foundAnalyzer:
+        if line.find("Static Analyzer") >= 0:
+          foundAnalyzer = True
+      else:
+        m = re.search('^(\s*ExecPath\s*=\s*")', line)
+        if m:
+          line = "".join([m.group(0), pathToChecker, '";\n'])
+      t.write(line)
+  t.close()
+  shutil.copy(t.name, path)
+  os.chmod(path, stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IROTH)
+  os.unlink(t.name)
+
+def main():
+  from optparse import OptionParser
+  parser = OptionParser('usage: %prog [options]')
+  parser.set_description(__doc__)
+  parser.add_option("--use-checker-build", dest="path",
+                    help="Use the Clang located at the provided absolute path, e.g. /Users/foo/checker-1")
+  parser.add_option("--use-xcode-clang", action="store_const", 
+                    const="$(CLANG)", dest="default",
+                    help="Use the Clang bundled with Xcode")
+  (options, args) = parser.parse_args()
+  if options.path is None and options.default is None:
+    parser.error("You must specify a version of Clang to use for static analysis.  Specify '-h' for details")
+
+  if options.path:
+    # Expand tildes.
+    path = os.path.expanduser(options.path)
+    if not path.endswith("clang"):
+      print "Using Clang bundled with checker build:", path
+      path = os.path.join(path, "bin", "clang");
+    else:
+      print "Using Clang located at:", path
+  else:
+    print "Using the Clang bundled with Xcode"
+    path = options.default
+
+  for x in FindClangSpecs('/Developer'):
+    ModifySpec(x, path)
+
+if __name__ == '__main__':
+  main()
+