1 // A hack for docs.rs to build documentation that has both windows and linux documentation in the
2 // same rustdoc build visible.
3 #[cfg(all(docsrs, not(windows)))]
4 mod windows_imports {
5     pub(super) enum WORD {}
6     pub(super) struct DWORD;
7     pub(super) enum HMODULE {}
8     pub(super) enum FARPROC {}
9 
10     pub(super) mod consts {
11         use super::DWORD;
12         pub(crate) const LOAD_IGNORE_CODE_AUTHZ_LEVEL: DWORD = DWORD;
13         pub(crate) const LOAD_LIBRARY_AS_DATAFILE: DWORD = DWORD;
14         pub(crate) const LOAD_LIBRARY_AS_DATAFILE_EXCLUSIVE: DWORD = DWORD;
15         pub(crate) const LOAD_LIBRARY_AS_IMAGE_RESOURCE: DWORD = DWORD;
16         pub(crate) const LOAD_LIBRARY_SEARCH_APPLICATION_DIR: DWORD = DWORD;
17         pub(crate) const LOAD_LIBRARY_SEARCH_DEFAULT_DIRS: DWORD = DWORD;
18         pub(crate) const LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR: DWORD = DWORD;
19         pub(crate) const LOAD_LIBRARY_SEARCH_SYSTEM32: DWORD = DWORD;
20         pub(crate) const LOAD_LIBRARY_SEARCH_USER_DIRS: DWORD = DWORD;
21         pub(crate) const LOAD_WITH_ALTERED_SEARCH_PATH: DWORD = DWORD;
22         pub(crate) const LOAD_LIBRARY_REQUIRE_SIGNED_TARGET: DWORD = DWORD;
23         pub(crate) const LOAD_LIBRARY_SAFE_CURRENT_DIRS: DWORD = DWORD;
24     }
25 }
26 #[cfg(any(not(docsrs), windows))]
27 mod windows_imports {
28     extern crate winapi;
with_dlerror<T, F>(wrap: fn(crate::error::DlDescription) -> crate::Error, closure: F) -> Result<T, Option<crate::Error>> where F: FnOnce() -> Option<T>29     pub(super) use self::winapi::shared::minwindef::{WORD, DWORD, HMODULE, FARPROC};
30     pub(super) use self::winapi::shared::ntdef::WCHAR;
31     pub(super) use self::winapi::um::{errhandlingapi, libloaderapi};
32     pub(super) use std::os::windows::ffi::{OsStrExt, OsStringExt};
33     pub(super) const SEM_FAILCE: DWORD = 1;
34 
35     pub(super) mod consts {
36         pub(crate) use super::winapi::um::libloaderapi::{
37             LOAD_IGNORE_CODE_AUTHZ_LEVEL,
38             LOAD_LIBRARY_AS_DATAFILE,
39             LOAD_LIBRARY_AS_DATAFILE_EXCLUSIVE,
40             LOAD_LIBRARY_AS_IMAGE_RESOURCE,
41             LOAD_LIBRARY_SEARCH_APPLICATION_DIR,
42             LOAD_LIBRARY_SEARCH_DEFAULT_DIRS,
43             LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR,
44             LOAD_LIBRARY_SEARCH_SYSTEM32,
45             LOAD_LIBRARY_SEARCH_USER_DIRS,
46             LOAD_WITH_ALTERED_SEARCH_PATH,
47             LOAD_LIBRARY_REQUIRE_SIGNED_TARGET,
48             LOAD_LIBRARY_SAFE_CURRENT_DIRS,
49         };
50     }
51 }
52 
53 use self::windows_imports::*;
54 use util::{ensure_compatible_types, cstr_cow_from_bytes};
55 use std::ffi::{OsStr, OsString};
56 use std::{fmt, io, marker, mem, ptr};
57 
58 /// A platform-specific counterpart of the cross-platform [`Library`](crate::Library).
59 pub struct Library(HMODULE);
60 
61 unsafe impl Send for Library {}
62 // Now, this is sort-of-tricky. MSDN documentation does not really make any claims as to safety of
63 // the Win32 APIs. Sadly, whomever I asked, even current and former Microsoft employees, couldn’t
64 // say for sure, whether the Win32 APIs used to implement `Library` are thread-safe or not.
65 //
66 // My investigation ended up with a question about thread-safety properties of the API involved
67 // being sent to an internal (to MS) general question mailing-list. The conclusion of the mail is
68 // as such:
69 //
70 // * Nobody inside MS (at least out of all the people who have seen the question) knows for
71 //   sure either;
72 // * However, the general consensus between MS developers is that one can rely on the API being
73 //   thread-safe. In case it is not thread-safe it should be considered a bug on the Windows
74 //   part. (NB: bugs filled at https://connect.microsoft.com/ against Windows Server)
75 unsafe impl Sync for Library {}
76 
77 impl Library {
78     /// Find and load a module.
79     ///
80     /// If the `filename` specifies a full path, the function only searches that path for the
81     /// module. Otherwise, if the `filename` specifies a relative path or a module name without a
82     /// path, the function uses a windows-specific search strategy to find the module; for more
83     /// information, see the [Remarks on MSDN][msdn].
84     ///
85     /// If the `filename` specifies a library filename without path and with extension omitted,
86     /// `.dll` extension is implicitly added. This behaviour may be suppressed by appending a
87     /// trailing `.` to the `filename`.
88     ///
89     /// This is equivalent to <code>[Library::load_with_flags](filename, 0)</code>.
90     ///
91     /// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryw#remarks
92     ///
93     /// # Safety
94     ///
95     /// When a library is loaded initialization routines contained within the library are executed.
96     /// For the purposes of safety, execution of these routines is conceptually the same calling an
97     /// unknown foreign function and may impose arbitrary requirements on the caller for the call
98     /// to be sound.
99     ///
100     /// Additionally, the callers of this function must also ensure that execution of the
101     /// termination routines contained within the library is safe as well. These routines may be
102     /// executed when the library is unloaded.
103     #[inline]
104     pub unsafe fn new<P: AsRef<OsStr>>(filename: P) -> Result<Library, crate::Error> {
105         Library::load_with_flags(filename, 0)
106     }
107 
108     /// Get the `Library` representing the original program executable.
109     ///
110     /// Note that behaviour of `Library` loaded with this method is different from
111     /// Libraries loaded with [`os::unix::Library::this`]. For more information refer to [MSDN].
112     ///
113     /// Corresponds to `GetModuleHandleExW(0, NULL, _)`.
114     ///
115     /// [`os::unix::Library::this`]: crate::os::unix::Library::this
116     /// [MSDN]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-getmodulehandleexw
117     pub fn this() -> Result<Library, crate::Error> {
118         unsafe {
119             let mut handle: HMODULE = std::ptr::null_mut();
120             with_get_last_error(|source| crate::Error::GetModuleHandleExW { source }, || {
new<P: AsRef<OsStr>>(filename: P) -> Result<Library, crate::Error>121                 let result = libloaderapi::GetModuleHandleExW(0, std::ptr::null_mut(), &mut handle);
122                 if result == 0 {
123                     None
124                 } else {
125                     Some(Library(handle))
126                 }
127             }).map_err(|e| e.unwrap_or(crate::Error::GetModuleHandleExWUnknown))
128         }
129     }
130 
131     /// Get a module that is already loaded by the program.
132     ///
133     /// This function returns a `Library` corresponding to a module with the given name that is
134     /// already mapped into the address space of the process. If the module isn't found an error is
135     /// returned.
136     ///
137     /// If the `filename` does not include a full path and there are multiple different loaded
138     /// modules corresponding to the `filename`, it is impossible to predict which module handle
139     /// will be returned. For more information refer to [MSDN].
140     ///
141     /// If the `filename` specifies a library filename without path and with extension omitted,
this() -> Library142     /// `.dll` extension is implicitly added. This behaviour may be suppressed by appending a
143     /// trailing `.` to the `filename`.
144     ///
145     /// This is equivalent to `GetModuleHandleExW(0, filename, _)`.
146     ///
147     /// [MSDN]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-getmodulehandleexw
148     pub fn open_already_loaded<P: AsRef<OsStr>>(filename: P) -> Result<Library, crate::Error> {
149         let wide_filename: Vec<u16> = filename.as_ref().encode_wide().chain(Some(0)).collect();
150 
151         let ret = unsafe {
152             let mut handle: HMODULE = std::ptr::null_mut();
153             with_get_last_error(|source| crate::Error::GetModuleHandleExW { source }, || {
154                 // Make sure no winapi calls as a result of drop happen inside this closure, because
155                 // otherwise that might change the return value of the GetLastError.
156                 let result = libloaderapi::GetModuleHandleExW(0, wide_filename.as_ptr(), &mut handle);
157                 if result == 0 {
158                     None
159                 } else {
160                     Some(Library(handle))
161                 }
162             }).map_err(|e| e.unwrap_or(crate::Error::GetModuleHandleExWUnknown))
163         };
164 
165         drop(wide_filename); // Drop wide_filename here to ensure it doesn’t get moved and dropped
166                              // inside the closure by mistake. See comment inside the closure.
167         ret
168     }
169 
170     /// Find and load a module, additionally adjusting behaviour with flags.
171     ///
172     /// See [`Library::new`] for documentation on handling of the `filename` argument. See the
173     /// [flag table on MSDN][flags] for information on applicable values for the `flags` argument.
174     ///
175     /// Corresponds to `LoadLibraryExW(filename, reserved: NULL, flags)`.
176     ///
177     /// [flags]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters
178     ///
179     /// # Safety
180     ///
181     /// When a library is loaded initialization routines contained within the library are executed.
182     /// For the purposes of safety, execution of these routines is conceptually the same calling an
183     /// unknown foreign function and may impose arbitrary requirements on the caller for the call
184     /// to be sound.
185     ///
186     /// Additionally, the callers of this function must also ensure that execution of the
187     /// termination routines contained within the library is safe as well. These routines may be
188     /// executed when the library is unloaded.
189     pub unsafe fn load_with_flags<P: AsRef<OsStr>>(filename: P, flags: DWORD) -> Result<Library, crate::Error> {
get_impl<T, F>(&self, symbol: &[u8], on_null: F) -> Result<Symbol<T>, crate::Error> where F: FnOnce() -> Result<Symbol<T>, crate::Error>190         let wide_filename: Vec<u16> = filename.as_ref().encode_wide().chain(Some(0)).collect();
191         let _guard = ErrorModeGuard::new();
192 
193         let ret = with_get_last_error(|source| crate::Error::LoadLibraryExW { source }, || {
194             // Make sure no winapi calls as a result of drop happen inside this closure, because
195             // otherwise that might change the return value of the GetLastError.
196             let handle =
197                 libloaderapi::LoadLibraryExW(wide_filename.as_ptr(), std::ptr::null_mut(), flags);
198             if handle.is_null()  {
199                 None
200             } else {
201                 Some(Library(handle))
202             }
203         }).map_err(|e| e.unwrap_or(crate::Error::LoadLibraryExWUnknown));
204         drop(wide_filename); // Drop wide_filename here to ensure it doesn’t get moved and dropped
205                              // inside the closure by mistake. See comment inside the closure.
206         ret
207     }
208 
209     /// Get a pointer to function or static variable by symbol name.
210     ///
211     /// The `symbol` may not contain any null bytes, with an exception of last byte. A null
212     /// terminated `symbol` may avoid a string allocation in some cases.
213     ///
214     /// Symbol is interpreted as-is; no mangling is done. This means that symbols like `x::y` are
215     /// most likely invalid.
216     ///
217     /// # Safety
218     ///
219     /// Users of this API must specify the correct type of the function or variable loaded. Using a
220     /// `Symbol` with a wrong type is undefined.
221     pub unsafe fn get<T>(&self, symbol: &[u8]) -> Result<Symbol<T>, crate::Error> {
222         ensure_compatible_types::<T, FARPROC>()?;
223         let symbol = cstr_cow_from_bytes(symbol)?;
224         with_get_last_error(|source| crate::Error::GetProcAddress { source }, || {
225             let symbol = libloaderapi::GetProcAddress(self.0, symbol.as_ptr());
226             if symbol.is_null() {
227                 None
228             } else {
229                 Some(Symbol {
230                     pointer: symbol,
231                     pd: marker::PhantomData
232                 })
233             }
234         }).map_err(|e| e.unwrap_or(crate::Error::GetProcAddressUnknown))
235     }
236 
237     /// Get a pointer to function or static variable by ordinal number.
238     ///
239     /// # Safety
240     ///
241     /// Users of this API must specify the correct type of the function or variable loaded. Using a
242     /// `Symbol` with a wrong type is undefined.
243     pub unsafe fn get_ordinal<T>(&self, ordinal: WORD) -> Result<Symbol<T>, crate::Error> {
get<T>(&self, symbol: &[u8]) -> Result<Symbol<T>, crate::Error>244         ensure_compatible_types::<T, FARPROC>()?;
245         with_get_last_error(|source| crate::Error::GetProcAddress { source }, || {
246             let ordinal = ordinal as usize as *mut _;
247             let symbol = libloaderapi::GetProcAddress(self.0, ordinal);
248             if symbol.is_null() {
249                 None
250             } else {
251                 Some(Symbol {
252                     pointer: symbol,
253                     pd: marker::PhantomData
254                 })
255             }
256         }).map_err(|e| e.unwrap_or(crate::Error::GetProcAddressUnknown))
257     }
258 
259     /// Convert the `Library` to a raw handle.
260     pub fn into_raw(self) -> HMODULE {
261         let handle = self.0;
262         mem::forget(self);
263         handle
264     }
265 
266     /// Convert a raw handle to a `Library`.
267     ///
268     /// # Safety
269     ///
270     /// The handle shall be a result of a successful call of `LoadLibraryA`, `LoadLibraryW`,
271     /// `LoadLibraryExW`, `LoadLibraryExA` or a handle previously returned by the
272     /// `Library::into_raw` call.
273     pub unsafe fn from_raw(handle: HMODULE) -> Library {
274         Library(handle)
275     }
276 
277     /// Unload the library.
278     ///
279     /// You only need to call this if you are interested in handling any errors that may arise when
280     /// library is unloaded. Otherwise this will be done when `Library` is dropped.
281     ///
282     /// The underlying data structures may still get leaked if an error does occur.
283     pub fn close(self) -> Result<(), crate::Error> {
284         let result = with_get_last_error(|source| crate::Error::FreeLibrary { source }, || {
285             if unsafe { libloaderapi::FreeLibrary(self.0) == 0 } {
286                 None
287             } else {
get_singlethreaded<T>(&self, symbol: &[u8]) -> Result<Symbol<T>, crate::Error>288                 Some(())
289             }
290         }).map_err(|e| e.unwrap_or(crate::Error::FreeLibraryUnknown));
291         // While the library is not free'd yet in case of an error, there is no reason to try
292         // dropping it again, because all that will do is try calling `FreeLibrary` again. only
293         // this time it would ignore the return result, which we already seen failing…
294         std::mem::forget(self);
295         result
296     }
297 }
298 
into_raw(self) -> *mut raw::c_void299 impl Drop for Library {
300     fn drop(&mut self) {
301         unsafe { libloaderapi::FreeLibrary(self.0); }
302     }
303 }
304 
305 impl fmt::Debug for Library {
306     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
307         unsafe {
308             // FIXME: use Maybeuninit::uninit_array when stable
309             let mut buf =
310                 mem::MaybeUninit::<[mem::MaybeUninit::<WCHAR>; 1024]>::uninit().assume_init();
311             let len = libloaderapi::GetModuleFileNameW(self.0,
from_raw(handle: *mut raw::c_void) -> Library312                 (&mut buf[..]).as_mut_ptr().cast(), 1024) as usize;
313             if len == 0 {
314                 f.write_str(&format!("Library@{:p}", self.0))
315             } else {
316                 let string: OsString = OsString::from_wide(
317                     // FIXME: use Maybeuninit::slice_get_ref when stable
318                     &*(&buf[..len] as *const [_] as *const [WCHAR])
319                 );
320                 f.write_str(&format!("Library@{:p} from {:?}", self.0, string))
321             }
322         }
323     }
324 }
325 
326 /// Symbol from a library.
327 ///
close(self) -> Result<(), crate::Error>328 /// A major difference compared to the cross-platform `Symbol` is that this does not ensure the
329 /// `Symbol` does not outlive `Library` it comes from.
330 pub struct Symbol<T> {
331     pointer: FARPROC,
332     pd: marker::PhantomData<T>
333 }
334 
335 impl<T> Symbol<T> {
336     /// Convert the loaded Symbol into a handle.
337     pub fn into_raw(self) -> FARPROC {
338         let pointer = self.pointer;
339         mem::forget(self);
340         pointer
341     }
342 }
343 
344 impl<T> Symbol<Option<T>> {
drop(&mut self)345     /// Lift Option out of the symbol.
346     pub fn lift_option(self) -> Option<Symbol<T>> {
347         if self.pointer.is_null() {
348             None
349         } else {
350             Some(Symbol {
351                 pointer: self.pointer,
352                 pd: marker::PhantomData,
353             })
354         }
355     }
356 }
357 
358 unsafe impl<T: Send> Send for Symbol<T> {}
359 unsafe impl<T: Sync> Sync for Symbol<T> {}
360 
361 impl<T> Clone for Symbol<T> {
362     fn clone(&self) -> Symbol<T> {
363         Symbol { ..*self }
364     }
365 }
366 
367 impl<T> ::std::ops::Deref for Symbol<T> {
368     type Target = T;
into_raw(self) -> *mut raw::c_void369     fn deref(&self) -> &T {
370         unsafe {
371             // Additional reference level for a dereference on `deref` return value.
372             &*(&self.pointer as *const *mut _ as *const T)
373         }
374     }
375 }
376 
377 impl<T> fmt::Debug for Symbol<T> {
lift_option(self) -> Option<Symbol<T>>378     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
379         f.write_str(&format!("Symbol@{:p}", self.pointer))
380     }
381 }
382 
383 struct ErrorModeGuard(DWORD);
384 
385 impl ErrorModeGuard {
386     #[allow(clippy::if_same_then_else)]
387     fn new() -> Option<ErrorModeGuard> {
388         unsafe {
389             let mut previous_mode = 0;
390             if errhandlingapi::SetThreadErrorMode(SEM_FAILCE, &mut previous_mode) == 0 {
391                 // How in the world is it possible for what is essentially a simple variable swap
392                 // to fail?  For now we just ignore the error -- the worst that can happen here is
393                 // the previous mode staying on and user seeing a dialog error on older Windows
clone(&self) -> Symbol<T>394                 // machines.
395                 None
396             } else if previous_mode == SEM_FAILCE {
397                 None
398             } else {
399                 Some(ErrorModeGuard(previous_mode))
400             }
deref(&self) -> &T401         }
402     }
403 }
404 
405 impl Drop for ErrorModeGuard {
406     fn drop(&mut self) {
407         unsafe {
408             errhandlingapi::SetThreadErrorMode(self.0, ptr::null_mut());
409         }
410     }
411 }
412 
413 fn with_get_last_error<T, F>(wrap: fn(crate::error::WindowsError) -> crate::Error, closure: F)
414 -> Result<T, Option<crate::Error>>
415 where F: FnOnce() -> Option<T> {
416     closure().ok_or_else(|| {
417         let error = unsafe { errhandlingapi::GetLastError() };
418         if error == 0 {
419             None
420         } else {
421             Some(wrap(crate::error::WindowsError(io::Error::from_raw_os_error(error as i32))))
422         }
423     })
424 }
425 
426 /// Do not check AppLocker rules or apply Software Restriction Policies for the DLL.
427 ///
428 /// This action applies only to the DLL being loaded and not to its dependencies. This value is
429 /// recommended for use in setup programs that must run extracted DLLs during installation.
430 ///
431 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
432 pub const LOAD_IGNORE_CODE_AUTHZ_LEVEL: DWORD = consts::LOAD_IGNORE_CODE_AUTHZ_LEVEL;
433 
434 /// Map the file into the calling process’ virtual address space as if it were a data file.
dlopen(filename: *const raw::c_char, flags: raw::c_int) -> *mut raw::c_void435 ///
436 /// Nothing is done to execute or prepare to execute the mapped file. Therefore, you cannot call
437 /// functions like [`Library::get`] with this DLL. Using this value causes writes to read-only
438 /// memory to raise an access violation. Use this flag when you want to load a DLL only to extract
439 /// messages or resources from it.
440 ///
441 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
442 pub const LOAD_LIBRARY_AS_DATAFILE: DWORD = consts::LOAD_LIBRARY_AS_DATAFILE;
443 
444 /// Map the file into the calling process’ virtual address space as if it were a data file.
445 ///
446 /// Similar to [`LOAD_LIBRARY_AS_DATAFILE`], except that the DLL file is opened with exclusive
447 /// write access for the calling process. Other processes cannot open the DLL file for write access
448 /// while it is in use. However, the DLL can still be opened by other processes.
449 ///
450 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
451 pub const LOAD_LIBRARY_AS_DATAFILE_EXCLUSIVE: DWORD = consts::LOAD_LIBRARY_AS_DATAFILE_EXCLUSIVE;
452 
453 /// Map the file into the process’ virtual address space as an image file.
454 ///
455 /// The loader does not load the static imports or perform the other usual initialization steps.
456 /// Use this flag when you want to load a DLL only to extract messages or resources from it.
457 ///
458 /// Unless the application depends on the file having the in-memory layout of an image, this value
459 /// should be used with either [`LOAD_LIBRARY_AS_DATAFILE_EXCLUSIVE`] or
460 /// [`LOAD_LIBRARY_AS_DATAFILE`].
461 ///
462 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
463 pub const LOAD_LIBRARY_AS_IMAGE_RESOURCE: DWORD = consts::LOAD_LIBRARY_AS_IMAGE_RESOURCE;
464 
465 /// Search application's installation directory for the DLL and its dependencies.
466 ///
467 /// Directories in the standard search path are not searched. This value cannot be combined with
468 /// [`LOAD_WITH_ALTERED_SEARCH_PATH`].
469 ///
470 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
471 pub const LOAD_LIBRARY_SEARCH_APPLICATION_DIR: DWORD = consts::LOAD_LIBRARY_SEARCH_APPLICATION_DIR;
472 
473 /// Search default directories when looking for the DLL and its dependencies.
474 ///
475 /// This value is a combination of [`LOAD_LIBRARY_SEARCH_APPLICATION_DIR`],
476 /// [`LOAD_LIBRARY_SEARCH_SYSTEM32`], and [`LOAD_LIBRARY_SEARCH_USER_DIRS`]. Directories in the
477 /// standard search path are not searched. This value cannot be combined with
478 /// [`LOAD_WITH_ALTERED_SEARCH_PATH`].
479 ///
480 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
481 pub const LOAD_LIBRARY_SEARCH_DEFAULT_DIRS: DWORD = consts::LOAD_LIBRARY_SEARCH_DEFAULT_DIRS;
482 
483 /// Directory that contains the DLL is temporarily added to the beginning of the list of
484 /// directories that are searched for the DLL’s dependencies.
485 ///
486 /// Directories in the standard search path are not searched.
487 ///
488 /// The `filename` parameter must specify a fully qualified path. This value cannot be combined
489 /// with [`LOAD_WITH_ALTERED_SEARCH_PATH`].
490 ///
491 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
492 pub const LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR: DWORD = consts::LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR;
493 
494 /// Search `%windows%\system32` for the DLL and its dependencies.
495 ///
496 /// Directories in the standard search path are not searched. This value cannot be combined with
497 /// [`LOAD_WITH_ALTERED_SEARCH_PATH`].
498 ///
499 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
500 pub const LOAD_LIBRARY_SEARCH_SYSTEM32: DWORD = consts::LOAD_LIBRARY_SEARCH_SYSTEM32;
501 
502 ///  Directories added using the `AddDllDirectory` or the `SetDllDirectory` function are searched
503 ///  for the DLL and its dependencies.
504 ///
505 ///  If more than one directory has been added, the order in which the directories are searched is
506 ///  unspecified. Directories in the standard search path are not searched. This value cannot be
507 ///  combined with [`LOAD_WITH_ALTERED_SEARCH_PATH`].
508 ///
509 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
510 pub const LOAD_LIBRARY_SEARCH_USER_DIRS: DWORD = consts::LOAD_LIBRARY_SEARCH_USER_DIRS;
511 
512 /// If `filename specifies an absolute path, the system uses the alternate file search strategy
513 /// discussed in the [Remarks section] to find associated executable modules that the specified
514 /// module causes to be loaded.
515 ///
516 /// If this value is used and `filename` specifies a relative path, the behavior is undefined.
517 ///
518 /// If this value is not used, or if `filename` does not specify a path, the system uses the
519 /// standard search strategy discussed in the [Remarks section] to find associated executable
520 /// modules that the specified module causes to be loaded.
521 ///
522 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
523 ///
524 /// [Remarks]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#remarks
525 pub const LOAD_WITH_ALTERED_SEARCH_PATH: DWORD = consts::LOAD_WITH_ALTERED_SEARCH_PATH;
526 
527 /// Specifies that the digital signature of the binary image must be checked at load time.
528 ///
529 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
530 pub const LOAD_LIBRARY_REQUIRE_SIGNED_TARGET: DWORD = consts::LOAD_LIBRARY_REQUIRE_SIGNED_TARGET;
531 
532 /// Allow loading a DLL for execution from the current directory only if it is under a directory in
533 /// the Safe load list.
534 ///
535 /// See [flag documentation on MSDN](https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-loadlibraryexw#parameters).
536 pub const LOAD_LIBRARY_SAFE_CURRENT_DIRS: DWORD = consts::LOAD_LIBRARY_SAFE_CURRENT_DIRS;
537