1 # Copyright (c) 2014 Google Inc. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 """ 6 TestWin.py: a collection of helpers for testing on Windows. 7 """ 8 9 import errno 10 import os 11 import re 12 import sys 13 import subprocess 14 15 class Registry(object): 16 def _QueryBase(self, sysdir, key, value): 17 """Use reg.exe to read a particular key. 18 19 While ideally we might use the win32 module, we would like gyp to be 20 python neutral, so for instance cygwin python lacks this module. 21 22 Arguments: 23 sysdir: The system subdirectory to attempt to launch reg.exe from. 24 key: The registry key to read from. 25 value: The particular value to read. 26 Return: 27 stdout from reg.exe, or None for failure. 28 """ 29 # Skip if not on Windows or Python Win32 setup issue 30 if sys.platform not in ('win32', 'cygwin'): 31 return None 32 # Setup params to pass to and attempt to launch reg.exe 33 cmd = [os.path.join(os.environ.get('WINDIR', ''), sysdir, 'reg.exe'), 34 'query', key] 35 if value: 36 cmd.extend(['/v', value]) 37 p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE) 38 # Get the stdout from reg.exe, reading to the end so p.returncode is valid 39 # Note that the error text may be in [1] in some cases 40 text = p.communicate()[0] 41 # Check return code from reg.exe; officially 0==success and 1==error 42 if p.returncode: 43 return None 44 return text 45 46 def Query(self, key, value=None): 47 """Use reg.exe to read a particular key through _QueryBase. 48 49 First tries to launch from %WinDir%\Sysnative to avoid WoW64 redirection. If 50 that fails, it falls back to System32. Sysnative is available on Vista and 51 up and available on Windows Server 2003 and XP through KB patch 942589. Note 52 that Sysnative will always fail if using 64-bit python due to it being a 53 virtual directory and System32 will work correctly in the first place. 54 55 KB 942589 - http://support.microsoft.com/kb/942589/en-us. 56 57 Arguments: 58 key: The registry key. 59 value: The particular registry value to read (optional). 60 Return: 61 stdout from reg.exe, or None for failure. 62 """ 63 text = None 64 try: 65 text = self._QueryBase('Sysnative', key, value) 66 except OSError, e: 67 if e.errno == errno.ENOENT: 68 text = self._QueryBase('System32', key, value) 69 else: 70 raise 71 return text 72 73 def GetValue(self, key, value): 74 """Use reg.exe to obtain the value of a registry key. 75 76 Args: 77 key: The registry key. 78 value: The particular registry value to read. 79 Return: 80 contents of the registry key's value, or None on failure. 81 """ 82 text = self.Query(key, value) 83 if not text: 84 return None 85 # Extract value. 86 match = re.search(r'REG_\w+\s+([^\r]+)\r\n', text) 87 if not match: 88 return None 89 return match.group(1) 90 91 def KeyExists(self, key): 92 """Use reg.exe to see if a key exists. 93 94 Args: 95 key: The registry key to check. 96 Return: 97 True if the key exists 98 """ 99 if not self.Query(key): 100 return False 101 return True 102