From: Daira Hopwood <daira@jacaranda.org>
Date: Tue, 27 Oct 2015 14:47:11 +0000 (+0000)
Subject: Improve all of the Windows-specific error reporting.
X-Git-Url: https://git.rkrishnan.org/components/com_hotproperty/somewhere?a=commitdiff_plain;h=532fade643d6b4d4d63b5db3e41daa644b6c3fa3;p=tahoe-lafs%2Ftahoe-lafs.git

Improve all of the Windows-specific error reporting.
Also make the Windows function declarations more readable and consistent.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
---

diff --git a/src/allmydata/util/fileutil.py b/src/allmydata/util/fileutil.py
index 29e6d1b1..1133c261 100644
--- a/src/allmydata/util/fileutil.py
+++ b/src/allmydata/util/fileutil.py
@@ -521,8 +521,10 @@ def get_available_space(whichdir, reserved_space):
 
 if sys.platform == "win32":
     # <http://msdn.microsoft.com/en-us/library/aa363858%28v=vs.85%29.aspx>
-    CreateFileW = WINFUNCTYPE(HANDLE, LPCWSTR, DWORD, DWORD, LPVOID, DWORD, DWORD, HANDLE) \
-                      (("CreateFileW", windll.kernel32))
+    CreateFileW = WINFUNCTYPE(
+        HANDLE,  LPCWSTR, DWORD, DWORD, LPVOID, DWORD, DWORD, HANDLE,
+        use_last_error=True
+    )(("CreateFileW", windll.kernel32))
 
     GENERIC_WRITE        = 0x40000000
     FILE_SHARE_READ      = 0x00000001
@@ -531,10 +533,16 @@ if sys.platform == "win32":
     INVALID_HANDLE_VALUE = 0xFFFFFFFF
 
     # <http://msdn.microsoft.com/en-us/library/aa364439%28v=vs.85%29.aspx>
-    FlushFileBuffers = WINFUNCTYPE(BOOL, HANDLE)(("FlushFileBuffers", windll.kernel32))
+    FlushFileBuffers = WINFUNCTYPE(
+        BOOL,  HANDLE,
+        use_last_error=True
+    )(("FlushFileBuffers", windll.kernel32))
 
     # <http://msdn.microsoft.com/en-us/library/ms724211%28v=vs.85%29.aspx>
-    CloseHandle = WINFUNCTYPE(BOOL, HANDLE)(("CloseHandle", windll.kernel32))
+    CloseHandle = WINFUNCTYPE(
+        BOOL,  HANDLE,
+        use_last_error=True
+    )(("CloseHandle", windll.kernel32))
 
     # <http://social.msdn.microsoft.com/forums/en-US/netfxbcl/thread/4465cafb-f4ed-434f-89d8-c85ced6ffaa8/>
     def flush_volume(path):
@@ -549,10 +557,10 @@ if sys.platform == "win32":
                               None
                              )
         if hVolume == INVALID_HANDLE_VALUE:
-            raise WinError()
+            raise WinError(get_last_error())
 
         if FlushFileBuffers(hVolume) == 0:
-            raise WinError()
+            raise WinError(get_last_error())
 
         CloseHandle(hVolume)
 else:
@@ -575,10 +583,9 @@ def reraise(wrapper):
 if sys.platform == "win32":
     # <https://msdn.microsoft.com/en-us/library/windows/desktop/aa365512%28v=vs.85%29.aspx>
     ReplaceFileW = WINFUNCTYPE(
-        BOOL,
-          LPCWSTR, LPCWSTR, LPCWSTR, DWORD, LPVOID, LPVOID,
+        BOOL,  LPCWSTR, LPCWSTR, LPCWSTR, DWORD, LPVOID, LPVOID,
         use_last_error=True
-      )(("ReplaceFileW", windll.kernel32))
+    )(("ReplaceFileW", windll.kernel32))
 
     REPLACEFILE_IGNORE_MERGE_ERRORS = 0x00000002
 
diff --git a/src/allmydata/windows/inotify.py b/src/allmydata/windows/inotify.py
index 1a719f9a..c5099ca4 100644
--- a/src/allmydata/windows/inotify.py
+++ b/src/allmydata/windows/inotify.py
@@ -23,15 +23,18 @@ from allmydata.util.encodingutil import quote_output
 from allmydata.util import log, fileutil
 from allmydata.util.pollmixin import PollMixin
 
-from ctypes import WINFUNCTYPE, WinError, windll, POINTER, byref, create_string_buffer, addressof
+from ctypes import WINFUNCTYPE, WinError, windll, POINTER, byref, create_string_buffer, \
+    addressof, get_last_error
 from ctypes.wintypes import BOOL, HANDLE, DWORD, LPCWSTR, LPVOID
 
 # <http://msdn.microsoft.com/en-us/library/gg258116%28v=vs.85%29.aspx>
 FILE_LIST_DIRECTORY              = 1
 
 # <http://msdn.microsoft.com/en-us/library/aa363858%28v=vs.85%29.aspx>
-CreateFileW = WINFUNCTYPE(HANDLE, LPCWSTR, DWORD, DWORD, LPVOID, DWORD, DWORD, HANDLE) \
-                  (("CreateFileW", windll.kernel32))
+CreateFileW = WINFUNCTYPE(
+    HANDLE,  LPCWSTR, DWORD, DWORD, LPVOID, DWORD, DWORD, HANDLE,
+    use_last_error=True
+)(("CreateFileW", windll.kernel32))
 
 FILE_SHARE_READ                  = 0x00000001
 FILE_SHARE_WRITE                 = 0x00000002
@@ -42,11 +45,16 @@ OPEN_EXISTING                    = 3
 FILE_FLAG_BACKUP_SEMANTICS       = 0x02000000
 
 # <http://msdn.microsoft.com/en-us/library/ms724211%28v=vs.85%29.aspx>
-CloseHandle = WINFUNCTYPE(BOOL, HANDLE)(("CloseHandle", windll.kernel32))
+CloseHandle = WINFUNCTYPE(
+    BOOL,  HANDLE,
+    use_last_error=True
+)(("CloseHandle", windll.kernel32))
 
 # <http://msdn.microsoft.com/en-us/library/aa365465%28v=vs.85%29.aspx>
-ReadDirectoryChangesW = WINFUNCTYPE(BOOL, HANDLE, LPVOID, DWORD, BOOL, DWORD, POINTER(DWORD), LPVOID, LPVOID) \
-                            (("ReadDirectoryChangesW", windll.kernel32))
+ReadDirectoryChangesW = WINFUNCTYPE(
+    BOOL,  HANDLE, LPVOID, DWORD, BOOL, DWORD, POINTER(DWORD), LPVOID, LPVOID,
+    use_last_error=True
+)(("ReadDirectoryChangesW", windll.kernel32))
 
 FILE_NOTIFY_CHANGE_FILE_NAME     = 0x00000001
 FILE_NOTIFY_CHANGE_DIR_NAME      = 0x00000002
@@ -121,7 +129,7 @@ class FileNotifyInformation(object):
                                   None   # NULL -> no completion routine
                                  )
         if r == 0:
-            raise WinError()
+            raise WinError(get_last_error())
         self.data = self.buffer.raw[:bytes_returned.value]
 
     def __iter__(self):
@@ -157,8 +165,8 @@ def _open_directory(path_u):
                              None                         # no template file
                             )
     if hDirectory == INVALID_HANDLE_VALUE:
-        e = WinError()
-        raise OSError("Opening directory %s gave Windows error %r: %s" % (quote_output(path_u), e.args[0], e.args[1]))
+        e = WinError(get_last_error())
+        raise OSError("Opening directory %s gave WinError: %s" % (quote_output(path_u), e))
     return hDirectory