initial custom action library, "hello, world" quality

src/installer-ca/wcautil.cpp

Index: src/installer-ca/wcautil.cpp
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+//-------------------------------------------------------------------------------------------------
+// <copyright file="wcautil.cpp" company="Outercurve Foundation">
+//   Copyright (c) 2004, Outercurve Foundation.
+//   This software is released under Microsoft Reciprocal License (MS-RL).
+//   The license and further copyright text can be found in the file
+//   LICENSE.TXT at the root directory of the distribution.
+// </copyright>
+// 
+// <summary>
+//    Windows Installer XML CustomAction utility library.
+// </summary>
+//-------------------------------------------------------------------------------------------------
+
+#include "precomp.h"
+
+// globals
+HMODULE g_hInstCADLL;
+
+// statics
+static BOOL s_fInitialized;
+static MSIHANDLE s_hInstall;
+static MSIHANDLE s_hDatabase;
+static char s_szCustomActionLogName[32];
+static UINT s_iRetVal;
+
+
+/********************************************************************
+ WcaGlobalInitialize() - initializes the Wca library, should be 
+                         called once per custom action Dll during
+                         DllMain on DLL_PROCESS_ATTACH
+
+********************************************************************/
+extern "C" void WIXAPI WcaGlobalInitialize(
+    __in HINSTANCE hInst
+    )
+{
+    g_hInstCADLL = hInst;
+    MemInitialize();
+
+    AssertSetModule(g_hInstCADLL);
+    AssertSetDisplayFunction(WcaDisplayAssert);
+}
+
+
+/********************************************************************
+ WcaGlobalFinalize() - finalizes the Wca library, should be the
+                       called once per custom action Dll during
+                       DllMain on DLL_PROCESS_DETACH
+
+********************************************************************/
+extern "C" void WIXAPI WcaGlobalFinalize()
+{
+#ifdef DEBUG
+    if (WcaIsInitialized())
+    {
+        CHAR szBuf[2048];
+        StringCchPrintfA(szBuf, countof(szBuf), "CustomAction %s called WcaInitialize() but not WcaFinalize()", WcaGetLogName());
+
+        AssertSz(FALSE, szBuf);
+    }
+#endif
+    MemUninitialize();
+    g_hInstCADLL = NULL;
+}
+
+
+/********************************************************************
+ WcaInitialize() - initializes the Wca framework, should be the first 
+                   thing called by all CustomActions
+
+********************************************************************/
+extern "C" HRESULT WIXAPI WcaInitialize(
+    __in MSIHANDLE hInstall,
+    __in_z PCSTR szCustomActionLogName
+    )
+{
+    WCHAR wzCAFileName[MAX_PATH] = {0};
+    DWORD dwMajorVersion = 0; 
+    DWORD dwMinorVersion = 0; 
+
+    // these statics should be called once per CustomAction invocation.
+    // Darwin does doesn't preserve DLL state across CustomAction calls so
+    // these should always be initialized to NULL.  If that behavior changes
+    // we would need to do a careful review of all of our module/global data.
+    AssertSz(!s_fInitialized, "WcaInitialize() should only be called once per CustomAction");
+    Assert(NULL == s_hInstall);
+    Assert(NULL == s_hDatabase);
+    Assert(0 == *s_szCustomActionLogName);
+
+    HRESULT hr = S_OK;
+
+    s_fInitialized = TRUE;
+    s_iRetVal = ERROR_SUCCESS; // assume all will go well
+
+    s_hInstall = hInstall;
+    s_hDatabase = ::MsiGetActiveDatabase(s_hInstall); // may return null if deferred CustomAction
+
+    hr = ::StringCchCopyA(s_szCustomActionLogName, countof(s_szCustomActionLogName), szCustomActionLogName);
+    ExitOnFailure1(hr, "Failed to copy CustomAction log name: %s", szCustomActionLogName);
+
+    // If we got the database handle IE: immediate CA
+    if (s_hDatabase)
+    {
+        hr = SetVerboseLoggingAtom(IsVerboseLogging());
+        ExitOnFailure(hr, "Failed to set verbose logging global atom");
+    }
+
+    if (!::GetModuleFileNameW(g_hInstCADLL, wzCAFileName, countof(wzCAFileName)))
+    {
+        ExitWithLastError(hr, "Failed to get module filename");
+    }
+
+    FileVersion(wzCAFileName, &dwMajorVersion, &dwMinorVersion);  // Ignore failure, just log 0.0.0.0
+
+    WcaLog(LOGMSG_VERBOSE, "Entering %s in %ls, version %u.%u.%u.%u", szCustomActionLogName, wzCAFileName, (DWORD)HIWORD(dwMajorVersion), (DWORD)LOWORD(dwMajorVersion), (DWORD)HIWORD(dwMinorVersion), (DWORD)LOWORD(dwMinorVersion));
+
+    Assert(s_hInstall);
+LExit:
+    if (FAILED(hr))
+    {
+        if (s_hDatabase)
+        {
+            ::MsiCloseHandle(s_hDatabase);
+            s_hDatabase = NULL;
+        }
+
+        s_hInstall = NULL;
+        s_fInitialized = FALSE;
+    }
+
+    return hr;
+}
+
+
+/********************************************************************
+ WcaFinalize() - cleans up after the Wca framework, should be the last 
+                 thing called by all CustomActions
+
+********************************************************************/
+extern "C" UINT WIXAPI WcaFinalize(
+    __in UINT iReturnValue
+    )
+{
+    AssertSz(!WcaIsWow64Initialized(), "WcaFinalizeWow64() should be called before calling WcaFinalize()");
+
+    // clean up after our initialization
+    if (s_hDatabase)
+    {
+        ::MsiCloseHandle(s_hDatabase);
+        s_hDatabase = NULL;
+    }
+
+    s_hInstall = NULL;
+    s_fInitialized = FALSE;
+
+    // if no error occurred during the processing of the CusotmAction return the passed in return value
+    // otherwise return the previous failure
+    return (ERROR_SUCCESS == s_iRetVal) ? iReturnValue : s_iRetVal; 
+}
+
+
+/********************************************************************
+ WcaIsInitialized() - determines if WcaInitialize() has been called
+
+********************************************************************/
+extern "C" BOOL WIXAPI WcaIsInitialized()
+{
+    return s_fInitialized;
+}
+
+
+/********************************************************************
+ WcaGetInstallHandle() - gets the handle to the active install session
+
+********************************************************************/
+extern "C" MSIHANDLE WIXAPI WcaGetInstallHandle()
+{
+    AssertSz(s_hInstall, "WcaInitialize() should be called before attempting to access the install handle.");
+    return s_hInstall;
+}
+
+
+/********************************************************************
+ WcaGetDatabaseHandle() - gets the handle to the active database
+
+ NOTE: this function can only be used in immediate CustomActions.
+       Deferred CustomActions do not have access to the active
+       database.
+********************************************************************/
+extern "C" MSIHANDLE WIXAPI WcaGetDatabaseHandle()
+{
+    AssertSz(s_hDatabase, "WcaInitialize() should be called before attempting to access the install handle.  Also note that deferred CustomActions do not have access to the active database.");
+    return s_hDatabase;
+}
+
+
+/********************************************************************
+ WcaGetLogName() - gets the name of the CustomAction used in logging
+
+********************************************************************/
+extern "C" const char* WIXAPI WcaGetLogName()
+{
+    return s_szCustomActionLogName;
+}
+
+
+/********************************************************************
+ WcaSetReturnValue() - sets the value to return from the CustomAction
+
+********************************************************************/
+extern "C" void WIXAPI WcaSetReturnValue(
+    __in UINT iReturnValue
+    )
+{
+    s_iRetVal = iReturnValue;
+}
+
+
+/********************************************************************
+ WcaCancelDetected() - determines if the user has canceled yet
+
+ NOTE: returns true when WcaSetReturnValue() is set to ERROR_INSTALL_USEREXIT
+********************************************************************/
+extern "C" BOOL WIXAPI WcaCancelDetected()
+{
+    return ERROR_INSTALL_USEREXIT == s_iRetVal;
+}