1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
|
// Scintilla source code edit control
/** @file WinTypes.h
** Implement safe release of COM objects and access to functions in DLLs.
** Header contains all implementation - there is no .cxx file.
**/
// Copyright 2020-2021 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
#ifndef WINTYPES_H
#define WINTYPES_H
namespace Scintilla::Internal {
// Release an IUnknown* and set to nullptr.
// While IUnknown::Release must be noexcept, it isn't marked as such so produces
// warnings which are avoided by the catch.
template <class T>
inline void ReleaseUnknown(T *&ppUnknown) noexcept {
if (ppUnknown) {
try {
ppUnknown->Release();
} catch (...) {
// Never occurs
}
ppUnknown = nullptr;
}
}
struct UnknownReleaser {
// Called by unique_ptr to destroy/free the resource
template <class T>
void operator()(T *pUnknown) noexcept {
try {
pUnknown->Release();
} catch (...) {
// IUnknown::Release must not throw, ignore if it does.
}
}
};
/// Find a function in a DLL and convert to a function pointer.
/// This avoids undefined and conditionally defined behaviour.
template<typename T>
inline T DLLFunction(HMODULE hModule, LPCSTR lpProcName) noexcept {
if (!hModule) {
return nullptr;
}
FARPROC function = ::GetProcAddress(hModule, lpProcName);
static_assert(sizeof(T) == sizeof(function));
T fp {};
memcpy(&fp, &function, sizeof(T));
return fp;
}
}
#endif
|
