diff options
Diffstat (limited to 'src/os/windows/mod.rs')
| -rw-r--r-- | src/os/windows/mod.rs | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/src/os/windows/mod.rs b/src/os/windows/mod.rs index da1b5c9..f1298f6 100644 --- a/src/os/windows/mod.rs +++ b/src/os/windows/mod.rs @@ -119,6 +119,45 @@ impl Library { } } + /// Load a module that is already loaded by the program. + /// + /// This function returns a `Library` corresponding to a module with the given name that is + /// already mapped into the address space of the process. If the module isn't found an error is + /// returned. + /// + /// If the `filename` does not include a full path and there are multiple different loaded + /// modules corresponding to the `filename`, it is impossible to predict which module handle + /// will be returned. For more information refer to [MSDN]. + /// + /// If the `filename` specifies a library filename without path and with extension omitted, + /// `.dll` extension is implicitly added. This behaviour may be suppressed by appending a + /// trailing `.` to the `filename`. + /// + /// This is equivalent to `GetModuleHandleExW(0, filename, _)`. + /// + /// [MSDN]: https://docs.microsoft.com/en-us/windows/win32/api/libloaderapi/nf-libloaderapi-getmodulehandleexw + pub fn open_already_loaded<P: AsRef<OsStr>>(filename: P) -> Result<Library, crate::Error> { + let wide_filename: Vec<u16> = filename.as_ref().encode_wide().chain(Some(0)).collect(); + + let ret = unsafe { + let mut handle: HMODULE = std::ptr::null_mut(); + with_get_last_error(|source| crate::Error::GetModuleHandleExW { source }, || { + // Make sure no winapi calls as a result of drop happen inside this closure, because + // otherwise that might change the return value of the GetLastError. + let result = libloaderapi::GetModuleHandleExW(0, wide_filename.as_ptr(), &mut handle); + if result == 0 { + None + } else { + Some(Library(handle)) + } + }).map_err(|e| e.unwrap_or(crate::Error::GetModuleHandleExWUnknown)) + }; + + drop(wide_filename); // Drop wide_filename here to ensure it doesn’t get moved and dropped + // inside the closure by mistake. See comment inside the closure. + ret + } + /// Find and load a module, additionally adjusting behaviour with flags. /// /// See [`Library::new`] for documentation on handling of the `filename` argument. See the |