From: Simon Rozman <simon@rozman.si>
Date: Tue, 16 Oct 2018 10:26:24 +0000 (+0200)
Subject: Prevent __stdcall name mangling of MSVC
X-Git-Tag: v2.5_beta1~363
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7d08c33cfc58eeb7286446c8d1ffd02939782332;p=thirdparty%2Fopenvpn.git

Prevent __stdcall name mangling of MSVC

Using `extern "C" __declspec(dllexport) __stdcall`, Win32 MSVC compiler
exports the functions are as `_name@N`. Exporting functions using
`/EXPORT` linker flag allows us to specify exact function name.

Note: The 64-bit MSVC compiler does not exhibit `__stdcall` name-
mangling.
Acked-by: Jon Kunkee <jkunkee@microsoft.com>
Message-Id: <20181016102627.18676-2-simon@rozman.si>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg17765.html

Signed-off-by: Gert Doering <gert@greenie.muc.de>
---

diff --git a/src/openvpnmsica/openvpnmsica.c b/src/openvpnmsica/openvpnmsica.c
index 823339910..3b90ce057 100644
--- a/src/openvpnmsica/openvpnmsica.c
+++ b/src/openvpnmsica/openvpnmsica.c
@@ -145,6 +145,10 @@ openvpnmsica_setup_sequence_filename(
 UINT __stdcall
 FindTAPInterfaces(_In_ MSIHANDLE hInstall)
 {
+#ifdef _MSC_VER
+#pragma comment(linker, DLLEXP_EXPORT)
+#endif
+
 #ifdef _DEBUG
     MessageBox(NULL, TEXT("Attach debugger!"), TEXT(__FUNCTION__) TEXT(" v")  TEXT(PACKAGE_VERSION), MB_OK);
 #endif
@@ -247,6 +251,10 @@ cleanup_CoInitialize:
 UINT __stdcall
 EvaluateTAPInterfaces(_In_ MSIHANDLE hInstall)
 {
+#ifdef _MSC_VER
+#pragma comment(linker, DLLEXP_EXPORT)
+#endif
+
 #ifdef _DEBUG
     MessageBox(NULL, TEXT("Attach debugger!"), TEXT(__FUNCTION__) TEXT(" v")  TEXT(PACKAGE_VERSION), MB_OK);
 #endif
@@ -505,6 +513,10 @@ cleanup_exec_seq:
 UINT __stdcall
 ProcessDeferredAction(_In_ MSIHANDLE hInstall)
 {
+#ifdef _MSC_VER
+#pragma comment(linker, DLLEXP_EXPORT)
+#endif
+
 #ifdef _DEBUG
     MessageBox(NULL, TEXT("Attach debugger!"), TEXT(__FUNCTION__) TEXT(" v")  TEXT(PACKAGE_VERSION), MB_OK);
 #endif
diff --git a/src/openvpnmsica/openvpnmsica.h b/src/openvpnmsica/openvpnmsica.h
index 3a64fbaa5..bb8e28ec4 100644
--- a/src/openvpnmsica/openvpnmsica.h
+++ b/src/openvpnmsica/openvpnmsica.h
@@ -55,6 +55,14 @@ extern DWORD openvpnmsica_tlsidx_session;
 extern "C" {
 #endif
 
+#ifdef __GNUC__
+#define DLLEXP_DECL __declspec(dllexport)
+#else
+#define DLLEXP_DECL
+#define DLLEXP_EXPORT "/EXPORT:"__FUNCTION__"="__FUNCDNAME__
+#endif
+
+
 /**
  * Find existing TAP interfaces and set TAPINTERFACES property with semicolon delimited list
  * of installed TAP interface GUIDs.
@@ -64,7 +72,7 @@ extern "C" {
  * @return ERROR_SUCCESS on success; An error code otherwise
  *         See: https://msdn.microsoft.com/en-us/library/windows/desktop/aa368072.aspx
  */
-__declspec(dllexport) UINT __stdcall
+DLLEXP_DECL UINT __stdcall
 FindTAPInterfaces(_In_ MSIHANDLE hInstall);
 
 
@@ -77,7 +85,7 @@ FindTAPInterfaces(_In_ MSIHANDLE hInstall);
  * @return ERROR_SUCCESS on success; An error code otherwise
  *         See: https://msdn.microsoft.com/en-us/library/windows/desktop/aa368072.aspx
  */
-__declspec(dllexport) UINT __stdcall
+DLLEXP_DECL UINT __stdcall
 EvaluateTAPInterfaces(_In_ MSIHANDLE hInstall);
 
 
@@ -89,7 +97,7 @@ EvaluateTAPInterfaces(_In_ MSIHANDLE hInstall);
  * @return ERROR_SUCCESS on success; An error code otherwise
  *         See: https://msdn.microsoft.com/en-us/library/windows/desktop/aa368072.aspx
  */
-__declspec(dllexport) UINT __stdcall
+DLLEXP_DECL UINT __stdcall
 ProcessDeferredAction(_In_ MSIHANDLE hInstall);
 
 #ifdef __cplusplus