kernel32: There is no need to zero-fill the FormatMessage() temporary buffer.
[wine] / dlls / kernel32 / change.c
1 /*
2  * Win32 file change notification functions
3  *
4  * Copyright 1998 Ulrich Weigand
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
19  */
20
21 #include "config.h"
22
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <string.h>
26
27 #include "ntstatus.h"
28 #define WIN32_NO_STATUS
29 #define NONAMELESSUNION
30 #define NONAMELESSSTRUCT
31 #include "windef.h"
32 #include "winbase.h"
33 #include "winerror.h"
34 #include "winternl.h"
35 #include "kernel_private.h"
36 #include "wine/debug.h"
37
38 WINE_DEFAULT_DEBUG_CHANNEL(file);
39
40 /****************************************************************************
41  *              FindFirstChangeNotificationA (KERNEL32.@)
42  */
43 HANDLE WINAPI FindFirstChangeNotificationA( LPCSTR lpPathName, BOOL bWatchSubtree,
44                                             DWORD dwNotifyFilter )
45 {
46     WCHAR *pathW;
47
48     if (!(pathW = FILE_name_AtoW( lpPathName, FALSE ))) return INVALID_HANDLE_VALUE;
49     return FindFirstChangeNotificationW( pathW, bWatchSubtree, dwNotifyFilter );
50 }
51
52 /*
53  * NtNotifyChangeDirectoryFile may write back to the IO_STATUS_BLOCK
54  * asynchronously.  We don't care about the contents, but it can't
55  * be placed on the stack since it will go out of scope when we return.
56  */
57 static IO_STATUS_BLOCK FindFirstChange_iosb;
58
59 /****************************************************************************
60  *              FindFirstChangeNotificationW (KERNEL32.@)
61  */
62 HANDLE WINAPI FindFirstChangeNotificationW( LPCWSTR lpPathName, BOOL bWatchSubtree,
63                                             DWORD dwNotifyFilter)
64 {
65     UNICODE_STRING nt_name;
66     OBJECT_ATTRIBUTES attr;
67     NTSTATUS status;
68     HANDLE handle = INVALID_HANDLE_VALUE;
69
70     TRACE( "%s %d %x\n", debugstr_w(lpPathName), bWatchSubtree, dwNotifyFilter );
71
72     if (!RtlDosPathNameToNtPathName_U( lpPathName, &nt_name, NULL, NULL ))
73     {
74         SetLastError( ERROR_PATH_NOT_FOUND );
75         return handle;
76     }
77
78     attr.Length = sizeof(attr);
79     attr.RootDirectory = 0;
80     attr.Attributes = OBJ_CASE_INSENSITIVE;
81     attr.ObjectName = &nt_name;
82     attr.SecurityDescriptor = NULL;
83     attr.SecurityQualityOfService = NULL;
84
85     status = NtOpenFile( &handle, FILE_LIST_DIRECTORY | SYNCHRONIZE,
86                          &attr, &FindFirstChange_iosb,
87                          FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
88                          FILE_DIRECTORY_FILE | FILE_SYNCHRONOUS_IO_NONALERT );
89     RtlFreeUnicodeString( &nt_name );
90
91     if (status != STATUS_SUCCESS)
92     {
93         SetLastError( RtlNtStatusToDosError(status) );
94         return INVALID_HANDLE_VALUE;
95     }
96
97     status = NtNotifyChangeDirectoryFile( handle, NULL, NULL, NULL,
98                                           &FindFirstChange_iosb,
99                                           NULL, 0, dwNotifyFilter, bWatchSubtree );
100     if (status != STATUS_PENDING)
101     {
102         NtClose( handle );
103         SetLastError( RtlNtStatusToDosError(status) );
104         return INVALID_HANDLE_VALUE;
105     }
106     return handle;
107 }
108
109 /****************************************************************************
110  *              FindNextChangeNotification (KERNEL32.@)
111  */
112 BOOL WINAPI FindNextChangeNotification( HANDLE handle )
113 {
114     NTSTATUS status;
115
116     TRACE("%p\n",handle);
117
118     status = NtNotifyChangeDirectoryFile( handle, NULL, NULL, NULL,
119                                           &FindFirstChange_iosb,
120                                           NULL, 0, FILE_NOTIFY_CHANGE_SIZE, 0 );
121     if (status != STATUS_PENDING)
122     {
123         SetLastError( RtlNtStatusToDosError(status) );
124         return FALSE;
125     }
126     return TRUE;
127 }
128
129 /****************************************************************************
130  *              FindCloseChangeNotification (KERNEL32.@)
131  */
132 BOOL WINAPI FindCloseChangeNotification( HANDLE handle )
133 {
134     return CloseHandle( handle );
135 }
136
137 static void WINAPI invoke_completion(LPVOID ctx, IO_STATUS_BLOCK *ios, ULONG res)
138 {
139     LPOVERLAPPED_COMPLETION_ROUTINE completion = ctx;
140     completion(ios->u.Status, ios->Information, (LPOVERLAPPED)ios);
141 }
142
143 /****************************************************************************
144  *              ReadDirectoryChangesW (KERNEL32.@)
145  *
146  * NOTES
147  *
148  *  The filter is remember from the first run and ignored on successive runs.
149  *
150  *  If there's no output buffer on the first run, it's ignored successive runs
151  *   and STATUS_NOTIFY_ENUM_DIRECTORY is returned with an empty buffer.
152  *
153  *  If a NULL overlapped->hEvent is passed, the directory handle is used
154  *   for signalling.
155  */
156 BOOL WINAPI ReadDirectoryChangesW( HANDLE handle, LPVOID buffer, DWORD len, BOOL subtree,
157                                    DWORD filter, LPDWORD returned, LPOVERLAPPED overlapped,
158                                    LPOVERLAPPED_COMPLETION_ROUTINE completion )
159 {
160     OVERLAPPED ov, *pov;
161     IO_STATUS_BLOCK *ios;
162     NTSTATUS status;
163     BOOL ret = TRUE;
164     LPVOID cvalue = NULL;
165
166     TRACE("%p %p %08x %d %08x %p %p %p\n", handle, buffer, len, subtree, filter,
167            returned, overlapped, completion );
168
169     if (!overlapped)
170     {
171         memset( &ov, 0, sizeof ov );
172         ov.hEvent = CreateEventW( NULL, 0, 0, NULL );
173         pov = &ov;
174     }
175     else
176     {
177         pov = overlapped;
178         if(completion) cvalue = completion;
179         else if (((ULONG_PTR)overlapped->hEvent & 1) == 0) cvalue = overlapped;
180     }
181
182     ios = (PIO_STATUS_BLOCK) pov;
183     ios->u.Status = STATUS_PENDING;
184
185     status = NtNotifyChangeDirectoryFile( handle, completion && overlapped ? NULL : pov->hEvent,
186             completion && overlapped ? invoke_completion : NULL,
187             cvalue, ios, buffer, len, filter, subtree );
188     if (status == STATUS_PENDING)
189     {
190         if (overlapped)
191             return TRUE;
192
193         WaitForSingleObjectEx( ov.hEvent, INFINITE, TRUE );
194         CloseHandle( ov.hEvent );
195         if (returned)
196             *returned = ios->Information;
197         status = ios->u.Status;
198     }
199
200     if (status != STATUS_SUCCESS)
201     {
202         SetLastError( RtlNtStatusToDosError(status) );
203         ret = FALSE;
204     }
205
206     return ret;
207 }