MDEV-19781 fixups

- It is not enough to have  and DeleteSymlinks actions
because within the same installation some exes executables can be both
added and removed, which needs both adding and removing some symlinks.

Instead of CreateSymlinks, there is now FixSymlinks function, which
goes through the list, and adds or removes the symlinks as needed.

- Implemented rollback for symlink custom action.

- Generate list of symlinks in C++ file, using CMake, rather than storing
lists as MSI properties.

cmake/symlinks.cmake

 # Create lists
+if(COMMAND REGISTER_SYMLINK)
+  return()
+endif()
+
 macro(REGISTER_SYMLINK from to)
   list(APPEND MARIADB_SYMLINK_FROMS ${from})
   list(APPEND MARIADB_SYMLINK_TOS ${to})

win/packaging/ca/CMakeLists.txt

@@ -14,9 +14,20 @@
 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1335  USA
 
 INCLUDE_DIRECTORIES(${WIX_DIR}/../SDK/${WIX_MSVC_SUFFIX}/inc)
-SET(WIXCA_SOURCES CustomAction.cpp CustomAction.def)
+SET(WIXCA_SOURCES CustomAction.cpp CustomAction.def ${CMAKE_CURRENT_BINARY_DIR}/symlinks.cc)
 
-INCLUDE_DIRECTORIES(${CMAKE_SOURCE_DIR}/sql)
+INCLUDE_DIRECTORIES(${CMAKE_SOURCE_DIR}/sql ${CMAKE_CURRENT_SOURCE_DIR})
+
+INCLUDE(symlinks)
+LIST(LENGTH MARIADB_SYMLINK_FROMS LEN)
+MATH(EXPR max_index "${LEN}-1")
+SET(ALL_SYMLINKS "")
+FOREACH(i RANGE 0 ${max_index})
+  LIST(GET MARIADB_SYMLINK_FROMS ${i} src)
+  LIST(GET MARIADB_SYMLINK_TOS ${i} dst)
+  STRING(APPEND ALL_SYMLINKS "{L\"${src}\",L\"${dst}\"},\n")
+ENDFOREACH()
+CONFIGURE_FILE(symlinks.cc.in symlinks.cc)
 
 # Custom action should not depend on C runtime, since we do not know if CRT is installed.
 FORCE_STATIC_CRT()

win/packaging/ca/CustomAction.cpp

@@ -746,7 +746,7 @@ extern "C" UINT __stdcall PresetDatabaseProperties(MSIHANDLE hInstall)
 
   if (BufferPoolsizeParamLen && buff[0])
   {
-    WcaLog(LOGMSG_STANDARD, "BUFFERPOOLSIZE=%s, len=%u",buff, BufferPoolsizeParamLen);
+    WcaLog(LOGMSG_STANDARD, "BUFFERPOOLSIZE=%S, len=%u",buff, BufferPoolsizeParamLen);
     InnodbBufferPoolSize= _wtoi64(buff);
   }
   else
@@ -1013,304 +1013,268 @@ extern "C" BOOL WINAPI DllMain(
   return TRUE;
 }
 
-// check if file exists
-inline bool checkIfFileExists (wstring& name) {
-  string sLog = "checkIfFileExists, ";
 
-  string sName(name.begin(), name.end() );
-
-  ifstream f(sName);
-
-  sLog.append(sName);
-  sLog.append(", result: ");
-  bool fileExists = f.good();
-
-  if (f.good())
-    sLog.append("true");
-  else
-    sLog.append("false");
-
-  WcaLog(LOGMSG_STANDARD, sLog.c_str());
+static wstring MakeExePath(const wchar_t *installDir, const wchar_t *basename)
+{
+  wstring path(installDir);
+  if (path.back() != L'\\')
+    path.append(L"\\");
+  path.append(L"bin\\");
+  path.append(basename);
+  path.append(L".exe");
+  return path;
+}
 
-  return f.good();
+static wstring MakeExePath(const wchar_t *installDir, string basename)
+{
+  wstring path(installDir);
+  if (path.back() != L'\\')
+    path.append(L"\\");
+  path.append(L"bin\\");
+  for (auto c : basename)
+    path+= c;
+  path.append(L".exe");
+  return path;
+}
+static wstring MakeFixSymlinksLogPath()
+{
+  wchar_t buf[MAX_PATH];
+  if (GetTempPathW(MAX_PATH, buf))
+    return wstring(buf) + L"\\mariadb_msi_fix_symlinks.log";
+  return L"";
 }
 
-// string to wstring
-std::wstring s2ws(const std::string& s)
+static string w2s(wstring w)
 {
-    int len;
-    int slength = (int)s.length() + 1;
-    len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0);
-    wchar_t* buf = new wchar_t[len];
-    MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len);
-    std::wstring r(buf);
-    delete[] buf;
-    return r;
+  string s;
+  for (auto wc : w)
+    s += (char)wc;
+  return s;
 }
 
-/* MDEV-19781 MariaDB symlinks on Windows */
-extern "C" UINT __stdcall CreateSymlinks(MSIHANDLE hInstall)
+/*
+  Remove symlinks if target file does not exist.
+  Create symlink if target exists, but symlink is not.
+*/
+static void fix_symlink(const wchar_t *file, const wchar_t *link,
+                        const wchar_t *installdir,
+                        vector<string> &rollback_actions)
 {
-  HRESULT hr = S_OK;
-  UINT er = ERROR_SUCCESS;
-  wchar_t customActionData[10000];
-  wchar_t installDir[MAX_PATH];
-  DWORD len = 10000;
-  wchar_t installerVersion[MAX_VERSION_PROPERTY_SIZE];
-  DWORD size = MAX_VERSION_PROPERTY_SIZE;
-  wchar_t binDir[MAX_PATH];
-  size_t blen = NULL;
+  WcaLog(LOGMSG_STANDARD, "fix_symlink %S=>%S", link, file);
 
-  hr = WcaInitialize(hInstall, __FUNCTION__);
-  WcaLog(LOGMSG_STANDARD, "Initialized.");
+  auto tgt= MakeExePath(installdir, file);
+  auto lnk= MakeExePath(installdir, link);
+  auto target_path= tgt.c_str();
+  auto link_path= lnk.c_str();
 
-  if (MsiGetPropertyW(hInstall, L"CustomActionData", customActionData, &len) != ERROR_SUCCESS)
+  auto target_attr= GetFileAttributesW(target_path);
+  auto link_attr= GetFileAttributesW(link_path);
+  WcaLog(LOGMSG_STANDARD, "%S %s", target_path,
+         target_attr == INVALID_FILE_ATTRIBUTES ? "does not exist" : "exists");
+  WcaLog(LOGMSG_STANDARD, "%S %s", link_path,
+         link_attr == INVALID_FILE_ATTRIBUTES ? "does not exist" : "exists");
+
+  if (link_attr != INVALID_FILE_ATTRIBUTES &&
+      ((link_attr & FILE_ATTRIBUTE_REPARSE_POINT) == 0))
   {
-    hr = HRESULT_FROM_WIN32(GetLastError());
-    MsiProcessMessage(hInstall, INSTALLMESSAGE_INFO, hr);
+    WcaLog(LOGMSG_STANDARD, "%S is not a symlink!", link_path);
+    return;
   }
 
-  if (MsiGetPropertyW(hInstall, L"ProductVersion", installerVersion, &size) != ERROR_SUCCESS)
+  if (target_attr == INVALID_FILE_ATTRIBUTES)
   {
-    hr = HRESULT_FROM_WIN32(GetLastError());
-    MsiProcessMessage(hInstall, INSTALLMESSAGE_INFO, hr);
+    if (link_attr == INVALID_FILE_ATTRIBUTES)
+    {
+      return;
     }
-
-  MsiProcessMessage(hInstall, INSTALLMESSAGE_INFO, hr);
-
-  wstring wsCustomActionData(customActionData);
-  string sCustomActionData(wsCustomActionData.begin(), wsCustomActionData.end());
-  WcaLog(LOGMSG_STANDARD, sCustomActionData.c_str());
-
-  stringstream ss;
-  ss << sCustomActionData;
-  vector<string> vCustomActionData;
-
-  while( ss.good() )
+    auto ok= DeleteFileW(link_path);
+    WcaLog(LOGMSG_STANDARD, "DeleteFileW(L\"%S\") returned %s, last error %lu",
+           link_path, ok ? "success" : "error", GetLastError());
+    if (ok)
     {
-    string substr;
-    getline( ss, substr, '|' );
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vCustomActionData.push_back( substr );
+      rollback_actions.push_back(string("create_symlink ") + w2s(link) + " " +
+                                 w2s(file));
     }
-
-  int i = 0;
-  string sBinPath = "";
-  string sPathFrom = "";
-  string sPathTo = "";
-
-  for(auto const& value: vCustomActionData) {
-    if (i == 0) {
-        sBinPath = value;
-        sBinPath.append("bin\\");
-    } else if (i == 1) {
-        sPathFrom = value;
-    } else if (i == 2) {
-        sPathTo = value;
+    return;
   }
 
-    WcaLog(LOGMSG_STANDARD, value.c_str());
-
-    i++;
-  }
+  if (link_attr != INVALID_FILE_ATTRIBUTES)
+    return;
 
-  WcaLog(LOGMSG_STANDARD, sBinPath.c_str());
-  WcaLog(LOGMSG_STANDARD, sPathFrom.c_str());
-  WcaLog(LOGMSG_STANDARD, sPathTo.c_str());
+  auto ok= CreateSymbolicLinkW(link_path, target_path, 0);
+  WcaLog(LOGMSG_STANDARD,
+         "CreateSymbolicLinkW(\"%S\",\"%S\", 0) returned %s, last error %d",
+         link_path, target_path, ok ? "success" : "error",
+         (int) GetLastError());
+  if (ok)
+    rollback_actions.push_back(string("delete ") + w2s(link));
+}
 
-  stringstream ssPathFrom, ssPathTo;
-  ssPathFrom << sPathFrom;
-  ssPathTo << sPathTo;
-  vector<string> vPathFrom;
-  vector<string> vPathTo;
+static string rollback_info_path()
+{
+  char tmppath[MAX_PATH];
+  if (!GetTempPathA(MAX_PATH, tmppath))
+    return "";
+  string filepath(tmppath);
+  filepath.append("\\mariadb_symlink_rollback_info.tmp");
+  return filepath;
+}
 
-  while(ssPathFrom.good()) {
-    string substr = "";
-    getline(ssPathFrom, substr, ';');
-    substr = substr.insert(0, sBinPath);
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vPathFrom.push_back(substr);
-  }
 
-  while(ssPathTo.good()) {
-    string substr = "";
-    getline(ssPathTo, substr, ';');
-    substr = substr.insert(0, sBinPath);
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vPathTo.push_back(substr);
+static void save_symlink_rollback_info(vector<string> rollback_info)
+{
+  std::ofstream ofs;
+  string path = rollback_info_path();
+  ofs.open(path, std::ofstream::out | std::ofstream::trunc);
+  if (!ofs.good())
+    return;
+  WcaLog(LOGMSG_STANDARD,
+    "Storing this rollback script for custom action in %s, in case installation rolls back",
+    path.c_str());
+  for (auto line : rollback_info)
+  {
+    WcaLog(LOGMSG_STANDARD, "%s", line.c_str());
+    ofs << line << "\n";
   }
+  WcaLog(LOGMSG_STANDARD, "End of rollback script");
+}
 
-  i = 0;
-
-  for(auto const& value: vPathTo) {
-    string &sTmpPathFrom = vPathFrom[i];
-    string &sTmpPathTo = vPathTo[i];
-
-    sTmpPathFrom.append(".exe");
-    sTmpPathTo.append(".exe");
-
-    wstring wsPathFrom = s2ws(sTmpPathFrom);
-    LPCWSTR lPathFrom = wsPathFrom.c_str();
-    wstring wsPathTo = s2ws(sTmpPathTo);
-    LPCWSTR lPathTo = wsPathTo.c_str();
-
-    int createdSymlink = -1;
 
-    if (checkIfFileExists(wsPathFrom))
-        createdSymlink = CreateSymbolicLinkW(wsPathTo.c_str(), wsPathFrom.c_str(), 0);
+#include <symlinks.h>
+/* MDEV-19781 MariaDB symlinks on Windows */
+extern "C" UINT __stdcall FixSymlinksRollback(MSIHANDLE hInstall)
+{
+  HRESULT hr= S_OK;
+  UINT er= ERROR_SUCCESS;
+  wchar_t targetdir[MAX_PATH];
+  DWORD len= MAX_PATH;
+  hr= WcaInitialize(hInstall, __FUNCTION__);
+  WcaLog(LOGMSG_STANDARD, "Initialized.");
+  std::ifstream ifs;
+  std::string command;
 
-    string created = "Created symlink: ";
-    created.append(sTmpPathTo);
-    created.append(" --> ");
-    created.append(sTmpPathFrom);
-    created.append(", result= ");
-    created.append(to_string(createdSymlink));
+  if (MsiGetPropertyW(hInstall, L"CustomActionData", targetdir, &len) !=
+      ERROR_SUCCESS)
+  {
+    hr= HRESULT_FROM_WIN32(GetLastError());
+    ExitOnFailure(hr, "MsiGetPropertyW failed");
+  }
 
-    WcaLog(LOGMSG_STANDARD, created.c_str());
+  ifs.open(rollback_info_path(), std::ofstream::in);
+  if (!ifs.good())
+    goto LExit;
 
-    i++;
+  while (ifs >> command)
+  {
+    if (command == "create_symlink")
+    {
+      string link;
+      ifs >> link;
+      auto link_path= MakeExePath(targetdir, link);
+      string file;
+      ifs >> file;
+      auto target_path= MakeExePath(targetdir, file);
+      bool ok= CreateSymbolicLinkW(link_path.c_str(), target_path.c_str(), 0);
+      WcaLog(LOGMSG_STANDARD, "CreateSymbolicLinkW(%S,%S) %s, last error %lu",
+             link_path.c_str(), target_path.c_str(), ok ? "success" : "error",
+             GetLastError());
+    }
+    else if (command == "delete")
+    {
+      string link;
+      ifs >> link;
+      auto link_path= MakeExePath(targetdir, link);
+      auto link_attr= GetFileAttributesW(link_path.c_str());
+      if (link_attr != INVALID_FILE_ATTRIBUTES &&
+          (link_attr & FILE_ATTRIBUTE_REPARSE_POINT))
+      {
+        auto ok= DeleteFileW(link_path.c_str());
+        WcaLog(LOGMSG_STANDARD, "DeleteFile(%S) %s, last error %lu",
+               link_path.c_str(), ok ? "success" : "error", GetLastError());
+      }
+    }
+    else
+    {
+      WcaLog(LOGMSG_STANDARD, "Unknown command '%s' in rollback script ",
+             command.c_str());
+      goto LExit;
+    }
   }
 
-  ReleaseStr(installDir);
-  ReleaseStr(installerVersion);
-  ReleaseStr(binDir);
+LExit:
   return WcaFinalize(er);
 }
 
-/* MDEV-19781 MariaDB symlinks on Windows */
-extern "C" UINT __stdcall DeleteSymlinks(MSIHANDLE hInstall)
+
+extern "C" UINT __stdcall SymlinksUninstall(MSIHANDLE hInstall)
 {
   HRESULT hr = S_OK;
   UINT er = ERROR_SUCCESS;
-  wchar_t customActionData[10000];
-  wchar_t installDir[MAX_PATH];
-  DWORD len = 10000;
-  DWORD size = MAX_VERSION_PROPERTY_SIZE;
-  wchar_t binDir[MAX_PATH];
-  size_t blen = NULL;
-
+  wchar_t targetdir[MAX_PATH];
+  DWORD len = MAX_PATH;
+  int i;
   hr = WcaInitialize(hInstall, __FUNCTION__);
-  WcaLog(LOGMSG_STANDARD, "DeleteSymlinks initialized.");
+  WcaLog(LOGMSG_STANDARD, "Initialized.");
 
-  if (MsiGetPropertyW(hInstall, L"CustomActionData", customActionData, &len) != ERROR_SUCCESS)
+  if (MsiGetPropertyW(hInstall, L"CustomActionData", targetdir, &len) !=
+    ERROR_SUCCESS)
   {
     hr = HRESULT_FROM_WIN32(GetLastError());
-    MsiProcessMessage(hInstall, INSTALLMESSAGE_INFO, hr);
+    ExitOnFailure(hr, "MsiGetPropertyW failed");
   }
 
-  wstring wsCustomActionData(customActionData);
-  string sCustomActionData(wsCustomActionData.begin(), wsCustomActionData.end());
-  WcaLog(LOGMSG_STANDARD, sCustomActionData.c_str());
-
-  stringstream ss;
-  ss << sCustomActionData;
-  vector<string> vCustomActionData;
-
-  while( ss.good() )
+  for (i = 0; all_symlinks[i].file; i++)
   {
-    string substr;
-    getline( ss, substr, '|' );
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vCustomActionData.push_back( substr );
-  }
-
-  int i = 0;
-  string sBinPath = "";
-  string sPathFrom = "";
-  string sPathTo = "";
+    auto link_path = MakeExePath(targetdir, all_symlinks[i].link);
+    auto link_attr = GetFileAttributesW(link_path.c_str());
+    auto filepath = link_path.c_str();
 
-  for(auto const& value: vCustomActionData) {
-    if (i == 0) {
-        sBinPath = value;
-        sBinPath.append("bin\\");
-    } else if (i == 1) {
-        sPathFrom = value;
-    } else if (i == 2) {
-        sPathTo = value;
-    }
-
-    WcaLog(LOGMSG_STANDARD, value.c_str());
-
-    i++;
+    if (link_attr == INVALID_FILE_ATTRIBUTES)
+    {
+      WcaLog(LOGMSG_STANDARD, " %S does not exist",filepath);
+      continue;
     }
 
-  WcaLog(LOGMSG_STANDARD, sBinPath.c_str());
-  WcaLog(LOGMSG_STANDARD, sPathFrom.c_str());
-  WcaLog(LOGMSG_STANDARD, sPathTo.c_str());
-
-  stringstream ssPathFrom, ssPathTo;
-  ssPathFrom << sPathFrom;
-  ssPathTo << sPathTo;
-  vector<string> vPathFrom;
-  vector<string> vPathTo;
-
-  while(ssPathFrom.good()) {
-    string substr = "";
-    getline(ssPathFrom, substr, ';');
-    substr = substr.insert(0, sBinPath);
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vPathFrom.push_back(substr);
+    if(!(link_attr & FILE_ATTRIBUTE_REPARSE_POINT))
+    {
+      WcaLog(LOGMSG_STANDARD, " %S is not a symbolic link!",filepath);
+      continue;
     }
-
-  while(ssPathTo.good()) {
-    string substr = "";
-    getline(ssPathTo, substr, ';');
-    substr = substr.insert(0, sBinPath);
-    WcaLog(LOGMSG_STANDARD, substr.c_str());
-    vPathTo.push_back(substr);
+    BOOL ok = DeleteFileW(filepath);
+    WcaLog(LOGMSG_STANDARD, "DeleteFile(%S) %s, last error %lu",
+      filepath, ok? "succeeded":"failed", GetLastError());
   }
 
-  i = 0;
-
-  for(auto const& value: vPathTo) {
-    string &sTmpPathFrom = vPathFrom[i];
-    string &sTmpPathTo = vPathTo[i];
-
-    sTmpPathFrom.append(".exe");
-    sTmpPathTo.append(".exe");
-
-    wstring wsPathFrom = s2ws(sTmpPathFrom);
-    LPCWSTR lPathFrom = wsPathFrom.c_str();
-    wstring wsPathTo = s2ws(sTmpPathTo);
-    LPCWSTR lPathTo = wsPathTo.c_str();
-
-    int deletedSymlink = -1;
-
-    if (checkIfFileExists(wsPathTo))
-        deletedSymlink = DeleteFileW(wsPathTo.c_str());
-
-    string deleted = "Deleted symlink: ";
-    deleted.append(sTmpPathTo);
-    deleted.append(" --> ");
-    deleted.append(sTmpPathFrom);
-    deleted.append(", result= ");
-    deleted.append(to_string(deletedSymlink));
+LExit:
+  return WcaFinalize(er);
+}
 
-    WcaLog(LOGMSG_STANDARD, deleted.c_str());
+/* MDEV-19781 MariaDB symlinks on Windows */
+extern "C" UINT __stdcall FixSymlinks(MSIHANDLE hInstall)
+{
+  HRESULT hr= S_OK;
+  UINT er= ERROR_SUCCESS;
+  wchar_t targetdir[MAX_PATH];
+  vector<string> rollback_actions;
+  DWORD len= MAX_PATH;
+  int i;
+  hr= WcaInitialize(hInstall, __FUNCTION__);
+  WcaLog(LOGMSG_STANDARD, "Initialized.");
 
-    i++;
+  if (MsiGetPropertyW(hInstall, L"CustomActionData", targetdir, &len) !=
+      ERROR_SUCCESS)
+  {
+    hr= HRESULT_FROM_WIN32(GetLastError());
+    ExitOnFailure(hr, "MsiGetPropertyW failed");
   }
-/*
 
-  for(size_t i = 0; i < std::size(symlink_to); i++) {
-    wchar_t pathTo[MAX_PATH];
+  for (i= 0; all_symlinks[i].file; i++)
+    fix_symlink(all_symlinks[i].file, all_symlinks[i].link, targetdir,
+                rollback_actions);
 
-    wcscpy(pathTo, binDir);
-    wcscat(pathTo, symlink_to[i].data());
+  save_symlink_rollback_info(rollback_actions);
 
-    wstring wsPathTo(pathTo);
-
-    if ( checkIfFileExists(wsPathTo) ) {
-      DeleteFileW(pathTo);
-    } else {
-      hr = HRESULT_FROM_WIN32(GetLastError());
-      ExitOnFailure(hr, "Could not delete symlink");
-    }
-  }
-  
-*/
-
-  ReleaseStr(installDir);
-  ReleaseStr(binDir);
+LExit:
   return WcaFinalize(er);
 }
+

win/packaging/ca/CustomAction.def

@@ -8,5 +8,6 @@ CheckDatabaseProperties
 CheckDataDirectoryEmpty
 CheckDBInUse
 CheckServiceUpgrades
-CreateSymlinks
-DeleteSymlinks
+FixSymlinks
+FixSymlinksRollback
+SymlinksUninstall

win/packaging/ca/symlinks.cc.in

+#include "symlinks.h"
+symlink all_symlinks[]=
+{
+@ALL_SYMLINKS@
+{nullptr, nullptr}
+};

win/packaging/ca/symlinks.h

+#pragma once
+struct symlink
+{
+  const wchar_t *file;
+  const wchar_t *link;
+};
+
+extern symlink all_symlinks[];

win/packaging/create_msi.cmake

-# get the symlink lists
-#INCLUDE(${CMAKE_SOURCE_DIR}/../../cmake/symlinks.cmake)
-#INCLUDE(symlinks)
-INCLUDE(${CMAKE_CURRENT_LIST_DIR}/../../cmake/symlinks.cmake)
 
 MACRO(MAKE_WIX_IDENTIFIER str varname)
   STRING(REPLACE "/" "." ${varname} "${str}")

win/packaging/extra.wxs.in

@@ -63,9 +63,6 @@
     <Property Id="BUFFERPOOLSIZE" Secure="yes"/>
     <!-- Innodb page size -->
     <Property Id="PAGESIZE" Secure="yes" Value="16K"/>
-    <!-- Symlinks -->
-    <Property Id="SYMLINK_TOS" Value="@MARIADB_SYMLINK_TOS@" />
-    <Property Id="SYMLINK_FROMS" Value="@MARIADB_SYMLINK_FROMS@" />
 
     <CustomAction Id="LaunchUrl" BinaryKey="WixCA" DllEntry="WixShellExec"  Execute="immediate" Return="check" Impersonate="yes" />
 
@@ -665,16 +662,19 @@
    <?endif?>
    
     <!-- Custom action, create symlinks -->
-    <CustomAction Id="CreateSymlinks.SetProperty" Return="check" Property="CreateSymlinks" Value="[INSTALLDIR]|[SYMLINK_FROMS]|[SYMLINK_TOS]" />
-    <CustomAction Id="CreateSymlinks" BinaryKey="wixca.dll" DllEntry="CreateSymlinks" Execute="deferred" Impersonate="no" Return="ignore" />
-    <CustomAction Id="DeleteSymlinks.SetProperty" Return="check" Property="DeleteSymlinks" Value="[INSTALLDIR]|[SYMLINK_FROMS]|[SYMLINK_TOS]" />
-    <CustomAction Id='DeleteSymlinks' BinaryKey="wixca.dll" DllEntry="DeleteSymlinks" Execute="deferred" Impersonate="no" Return="ignore" />
-
+    <CustomAction Id="Symlinks.SetProperty" Return="check" Property="Symlinks" Value="[INSTALLDIR]" />
+    <CustomAction Id="Symlinks" BinaryKey="wixca.dll" DllEntry="FixSymlinks" Execute="deferred" Impersonate="no" Return="ignore"/>
+    <CustomAction Id="SymlinksRollback.SetProperty" Return="check" Property="SymlinksRollback" Value="[INSTALLDIR]" />
+    <CustomAction Id="SymlinksRollback" BinaryKey="wixca.dll" DllEntry="FixSymlinksRollback" Execute="rollback" Impersonate="no" Return="ignore"/>
+    <CustomAction Id="SymlinksUninstall.SetProperty" Return="check" Property="SymlinksUninstall" Value="[INSTALLDIR]" />
+    <CustomAction Id="SymlinksUninstall" BinaryKey="wixca.dll" DllEntry="SymlinksUninstall" Execute="deferred" Impersonate="no" Return="ignore"/>
     <InstallExecuteSequence>
-      <Custom Action="CreateSymlinks.SetProperty" Before="CreateSymlinks">NOT Installed</Custom>
-      <Custom Action="CreateSymlinks" Before="InstallFinalize">NOT Installed</Custom>
-      <Custom Action="DeleteSymlinks.SetProperty" Before="DeleteSymlinks">Installed AND NOT REINSTALL</Custom>
-      <Custom Action="DeleteSymlinks" Before="RemoveFiles">Installed AND NOT REINSTALL</Custom>
+      <Custom Action="Symlinks.SetProperty" Before="Symlinks">NOT Installed OR UPGRADINGPRODUCTCODE</Custom>
+      <Custom Action="Symlinks" After="SymlinksRollback">NOT Installed OR UPGRADINGPRODUCTCODE</Custom>
+      <Custom Action="SymlinksRollback.SetProperty" Before="SymlinksRollback">NOT Installed OR UPGRADINGPRODUCTCODE</Custom>
+      <Custom Action="SymlinksRollback" After="InstallFiles">NOT Installed OR UPGRADINGPRODUCTCODE</Custom>
+      <Custom Action="SymlinksUninstall.SetProperty" Before="SymlinksUninstall">Installed AND NOT UPGRADINGPRODUCTCODE</Custom>
+      <Custom Action="SymlinksUninstall" Before="RemoveFiles">Installed AND NOT UPGRADINGPRODUCTCODE</Custom>
     </InstallExecuteSequence>
 
     <!-- Custom action, call mysql_install_db -->
@@ -897,10 +897,10 @@
       >
       <![CDATA[ NOT(NSISINSTALLKEY << "MariaDB @MAJOR_VERSION@.@MINOR_VERSION@.") OR Installed]]>
     </Condition>
-    <!-- Condition Message=
+    <Condition Message=
        'Setting the ALLUSERS property is not allowed because [ProductName] is a per-machine application. Setup will now exit.'>
       <![CDATA[ALLUSERS = "1"]]>
-    </Condition -->
+    </Condition>
 	<Condition Message='This application is only supported on Windows Vista, Windows Server 2008, or higher.'>
       <![CDATA[Installed OR (VersionNT >= 600)]]>
     </Condition>