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stephenegriffinstephenegriffin
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Better fallbacks for finding olmapi32
1 parent 33740da commit 428a998

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2 files changed

+91
-54
lines changed

2 files changed

+91
-54
lines changed

‎library/stubutils.cpp‎

Lines changed: 88 additions & 52 deletions
Original file line numberDiff line numberDiff line change
@@ -103,6 +103,18 @@ namespace mapistub
103103
L"{BC174BAD-2F53-4855-A1D5-1D575C19B1EA}", // O11_CATEGORY_GUID_CORE_OFFICE (debug) // STRING_OK
104104
};
105105

106+
std::vector<std::wstring> g_OutlookQualifiers = {
107+
// Possible qualifiers for MsiProvideQualifiedComponent
108+
L"outlook.x64.exe",
109+
L"outlook.exe",
110+
L"excel.exe",
111+
L"winword.exe",
112+
L"wwlib.dll",
113+
L"powerpnt.exe",
114+
L"msaccess.exe",
115+
L"onenote.exe",
116+
L"mspub.exe"};
117+
106118
std::wstring GetInstalledOutlookMAPI(int iOutlook);
107119
std::wstring GetInstalledOutlookMAPI(const std::wstring component);
108120

@@ -262,6 +274,9 @@ namespace mapistub
262274
// Whether or not we should ignore the registry and load MAPI from the system directory
263275
static bool s_fForceSystemMAPI = false;
264276

277+
// Preference flag for olmapi32.dll, true by default
278+
static bool s_fPreferOlmapi32 = true;
279+
265280
static volatile HMODULE g_hinstMAPI = nullptr;
266281
HMODULE g_hModPstPrx32 = nullptr;
267282

@@ -468,70 +483,63 @@ namespace mapistub
468483
return hkeyMapiClient;
469484
}
470485

471-
// Looks up Outlook's path given its qualified component guid
472-
std::wstring GetOutlookPath(_In_ const std::wstring& szCategory, _Out_opt_ bool* lpb64)
486+
// Looks up olmapi32.dll path given a qualified component guid
487+
std::wstring GetOLMAPI32Path(_In_ const std::wstring& szCategory)
473488
{
474-
logLoadMapi(L"Enter GetOutlookPath: szCategory = %ws\n", szCategory.c_str());
489+
logLoadMapi(L"Enter GetOLMAPI32Path: szCategory = %ws\n", szCategory.c_str());
475490
DWORD dwValueBuf = 0;
476491
std::wstring path;
477492

478-
if (lpb64) *lpb64 = false;
479-
480-
auto hRes = MyMsiProvideQualifiedComponent(
481-
szCategory.c_str(),
482-
L"outlook.x64.exe", // STRING_OK
483-
static_cast<DWORD>(INSTALLMODE_DEFAULT),
484-
nullptr,
485-
&dwValueBuf);
486-
LogError(L"GetOutlookPath: MsiProvideQualifiedComponent(x64)", hRes);
487-
if (hRes == S_OK)
488-
{
489-
if (lpb64) *lpb64 = true;
490-
}
491-
else
493+
auto hRes = E_FAIL;
494+
int usedIndex = -1;
495+
for (int i = 0; i < static_cast<int>(g_OutlookQualifiers.size()); ++i)
492496
{
497+
logLoadMapi(L"GetOLMAPI32Path: qualifier = %ws\n", g_OutlookQualifiers[i].c_str());
498+
dwValueBuf = 0;
493499
hRes = MyMsiProvideQualifiedComponent(
494500
szCategory.c_str(),
495-
L"outlook.exe", // STRING_OK
501+
g_OutlookQualifiers[i].c_str(),
496502
static_cast<DWORD>(INSTALLMODE_DEFAULT),
497503
nullptr,
498504
&dwValueBuf);
499-
LogError(L"GetOutlookPath: MsiProvideQualifiedComponent(x86)", hRes);
505+
LogError(L"GetOLMAPI32Path: MsiProvideQualifiedComponent", hRes);
506+
if (hRes == S_OK)
507+
{
508+
usedIndex = i;
509+
break;
510+
}
500511
}
501512

502-
if (hRes == S_OK)
513+
if (hRes == S_OK && usedIndex != -1)
503514
{
504515
dwValueBuf += 1;
505516
const auto lpszTempPath = std::wstring(dwValueBuf, '\0');
506-
507517
hRes = MyMsiProvideQualifiedComponent(
508518
szCategory.c_str(),
509-
L"outlook.x64.exe", // STRING_OK
519+
g_OutlookQualifiers[usedIndex].c_str(),
510520
static_cast<DWORD>(INSTALLMODE_DEFAULT),
511521
const_cast<wchar_t*>(lpszTempPath.c_str()),
512522
&dwValueBuf);
513-
LogError(L"GetOutlookPath: MsiProvideQualifiedComponent(x64)", hRes);
514-
if (hRes != S_OK)
523+
LogError(L"GetOLMAPI32Path: MsiProvideQualifiedComponent (path)", hRes);
524+
if (hRes == S_OK && !lpszTempPath.empty())
515525
{
516-
hRes = MyMsiProvideQualifiedComponent(
517-
szCategory.c_str(),
518-
L"outlook.exe", // STRING_OK
519-
static_cast<DWORD>(INSTALLMODE_DEFAULT),
520-
const_cast<wchar_t*>(lpszTempPath.c_str()),
521-
&dwValueBuf);
522-
LogError(L"GetOutlookPath: MsiProvideQualifiedComponent(x86)", hRes);
523-
}
526+
WCHAR szDrive[_MAX_DRIVE] = {0};
527+
WCHAR szOutlookPath[MAX_PATH] = {0};
528+
const auto errNo = _wsplitpath_s(
529+
lpszTempPath.c_str(), szDrive, _MAX_DRIVE, szOutlookPath, MAX_PATH, nullptr, NULL, nullptr, NULL);
530+
LogError(L"GetOLMAPI32Path: _wsplitpath_s", errNo);
524531

525-
if (hRes == S_OK)
526-
{
527-
path = lpszTempPath;
528-
logLoadMapi(L"Exit GetOutlookPath: Path = %ws\n", path.c_str());
532+
if (errNo == ERROR_SUCCESS)
533+
{
534+
path = std::wstring(szDrive) + std::wstring(szOutlookPath) + WszOlMAPI32DLL;
535+
logLoadMapi(L"GetOLMAPI32Path: found %ws\n", path.c_str());
536+
}
529537
}
530538
}
531539

532540
if (path.empty())
533541
{
534-
logLoadMapi(L"Exit GetOutlookPath: nothing found\n");
542+
logLoadMapi(L"Exit GetOLMAPI32Path: nothing found\n");
535543
}
536544

537545
return path;
@@ -557,23 +565,12 @@ namespace mapistub
557565
{
558566
logLoadMapi(L"Enter GetInstalledOutlookMAPI(%s)\n", component.c_str());
559567

560-
auto lpszTempPath = GetOutlookPath(component, nullptr);
568+
auto szPath = GetOLMAPI32Path(component);
561569

562-
if (!lpszTempPath.empty())
570+
if (!szPath.empty())
563571
{
564-
WCHAR szDrive[_MAX_DRIVE] = {0};
565-
WCHAR szOutlookPath[MAX_PATH] = {0};
566-
const auto errNo = _wsplitpath_s(
567-
lpszTempPath.c_str(), szDrive, _MAX_DRIVE, szOutlookPath, MAX_PATH, nullptr, NULL, nullptr, NULL);
568-
LogError(L"GetOutlookPath: _wsplitpath_s", errNo);
569-
570-
if (errNo == ERROR_SUCCESS)
571-
{
572-
const auto szPath = std::wstring(szDrive) + std::wstring(szOutlookPath) + WszOlMAPI32DLL;
573-
574-
logLoadMapi(L"GetInstalledOutlookMAPI: found %ws\n", szPath.c_str());
575-
return szPath;
576-
}
572+
logLoadMapi(L"GetInstalledOutlookMAPI: found %ws\n", szPath.c_str());
573+
return szPath;
577574
}
578575

579576
logLoadMapi(L"Exit GetInstalledOutlookMAPI: found nothing\n");
@@ -595,42 +592,75 @@ namespace mapistub
595592
return paths;
596593
}
597594

595+
/*
596+
* GetMAPIPaths - Returns a list of possible MAPI DLL paths in order of preference.
597+
*
598+
* Order of preference:
599+
* 1. If ForceSystemMAPI is set, prefer the system directory MAPI32.dll only.
600+
* 2. If ForceOutlookMAPI is set, prefer the Outlook MAPI client registry key.
601+
* 3. DllPathEx registry value from the selected MAPI client.
602+
* 4. All installed Outlook MAPI implementations (from known component GUIDs).
603+
* 5. DllPath registry value from the selected MAPI client.
604+
* 6. MSI-based MAPI path from the selected MAPI client.
605+
* 7. If not forcing Outlook, fallback to system directory MAPI32.dll.
606+
*/
598607
std::vector<std::wstring> GetMAPIPaths()
599608
{
609+
// Holds the ordered list of possible MAPI DLL paths
600610
auto paths = std::vector<std::wstring>();
601611
std::wstring szPath;
612+
613+
// 1. If ForceSystemMAPI is set, only use the system directory MAPI32.dll
602614
if (s_fForceSystemMAPI)
603615
{
604616
szPath = GetMAPISystemDir();
605617
if (!szPath.empty()) paths.push_back(szPath);
606618
return paths;
607619
}
608620

621+
// 2. Select the MAPI client registry key: Outlook if forced, otherwise default
609622
auto hkeyMapiClient = HKEY{};
610623
if (s_fForceOutlookMAPI)
611624
hkeyMapiClient = GetHKeyMapiClient(WszOutlookMapiClientName);
612625
else
613626
hkeyMapiClient = GetHKeyMapiClient(L"");
614627

628+
// 3. Prefer DllPathEx registry value from the selected MAPI client
615629
szPath = RegQueryWszExpand(hkeyMapiClient, WszValueNameDllPathEx);
616630
if (!szPath.empty()) paths.push_back(szPath);
617631

632+
// 4. Add all installed Outlook MAPI implementations (from known component GUIDs)
618633
auto outlookPaths = GetInstalledOutlookMAPI();
619634
paths.insert(end(paths), std::begin(outlookPaths), std::end(outlookPaths));
620635

636+
// 5. Prefer DllPath registry value from the selected MAPI client
621637
szPath = RegQueryWszExpand(hkeyMapiClient, WszValueNameDllPath);
622638
if (!szPath.empty()) paths.push_back(szPath);
623639

640+
// 6. Prefer MSI-based MAPI path from the selected MAPI client
624641
szPath = GetMailClientFromMSIData(hkeyMapiClient);
625642
if (!szPath.empty()) paths.push_back(szPath);
626643

644+
// 7. If not forcing Outlook, fallback to system directory MAPI32.dll
627645
if (!s_fForceOutlookMAPI)
628646
{
629647
szPath = GetMAPISystemDir();
630648
if (!szPath.empty()) paths.push_back(szPath);
631649
}
632650

633651
if (hkeyMapiClient) RegCloseKey(hkeyMapiClient);
652+
653+
// If olmapi32 preference is set, bubble all olmapi32.dll paths to the top (case-insensitive)
654+
if (s_fPreferOlmapi32)
655+
{
656+
auto is_olmapi32 = [](const std::wstring& path) {
657+
std::wstring lower = path;
658+
std::transform(lower.begin(), lower.end(), lower.begin(), ::towlower);
659+
return lower.find(L"olmapi32.dll") != std::wstring::npos;
660+
};
661+
auto it = std::stable_partition(paths.begin(), paths.end(), is_olmapi32);
662+
}
663+
634664
return paths;
635665
}
636666

@@ -777,4 +807,10 @@ namespace mapistub
777807
logLoadMapi(L"ForceSystemMAPI: fForce = 0x%08X\n", fForce);
778808
s_fForceSystemMAPI = fForce;
779809
}
810+
811+
void PreferOlmapi32(bool fPrefer)
812+
{
813+
logLoadMapi(L"PreferOlmapi32: fPrefer = 0x%08X\n", fPrefer);
814+
s_fPreferOlmapi32 = fPrefer;
815+
}
780816
} // namespace mapistub

‎library/stubutils.h‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -37,8 +37,8 @@ namespace mapistub
3737
std::wstring GetComponentPath(const std::wstring& szComponent, const std::wstring& szQualifier, bool fInstall);
3838
extern std::vector<std::wstring> g_pszOutlookQualifiedComponents;
3939
std::vector<std::wstring> GetMAPIPaths();
40-
// Looks up Outlook's path given its qualified component guid
41-
std::wstring GetOutlookPath(_In_ const std::wstring& szCategory, _Out_opt_ bool* lpb64);
40+
// Looks up olmapi32.dll path using a qualified component guid
41+
std::wstring GetOLMAPI32Path(_In_ const std::wstring& szCategory);
4242
std::wstring GetInstalledOutlookMAPI(int iOutlook);
4343
std::wstring GetMAPISystemDir();
4444

@@ -49,4 +49,5 @@ namespace mapistub
4949
void UnloadPrivateMAPI();
5050
void ForceOutlookMAPI(bool fForce);
5151
void ForceSystemMAPI(bool fForce);
52+
void PreferOlmapi32(bool fPrefer);
5253
} // namespace mapistub

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