[RSHELL]

* Implement skeleton shell dde parser.

[SHELL32]
* Copy over the skeleton from rshell, and fill in the handlers for ViewFolder and ExploreFolder, with rudimentary implementations.

CORE-7552

svn path=/branches/shell-experiments/; revision=64395

base/shell/rshell/ShellDDE.cpp

@@ -21,9 +21,21 @@
 #include "precomp.h"
 #include <ddeml.h>
 #include <strsafe.h>
+#include <shlwapi_undoc.h>
 
 WINE_DEFAULT_DEBUG_CHANNEL(shelldde);
 
+typedef DWORD(CALLBACK * pfnCommandHandler)(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS);
+
+struct DDECommandHandler
+{
+    WCHAR Command[32];
+    pfnCommandHandler Handler;
+};
+
+extern DDECommandHandler HandlerList [];
+extern const int HandlerListLength;
+
 /* DDE Instance ID */
 static DWORD dwDDEInst;
 
@@ -34,6 +46,8 @@ static HSZ hszShell;
 static HSZ hszAppProperties;
 static HSZ hszFolders;
 
+static BOOL bInitialized;
+
 static BOOL Dde_OnConnect(HSZ hszTopic, HSZ hszService)
 {
     WCHAR szTopic[MAX_PATH];
@@ -54,7 +68,7 @@ static void Dde_OnConnectConfirm(HCONV hconv, HSZ hszTopic, HSZ hszService)
 
     DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
     DdeQueryStringW(dwDDEInst, hszService, szService, _countof(szService), CP_WINUNICODE);
-    
+
     DbgPrint("Dde_OnConnectConfirm: hconv=%p, topic=%S, service=%S\n", hconv, szTopic, szService);
 }
 
@@ -84,6 +98,32 @@ static HDDEDATA Dde_OnRequest(UINT uFmt, HCONV hconv, HSZ hszTopic, HSZ hszItem)
     return NULL;
 }
 
+static LPITEMIDLIST _ILReadFromSharedMemory(PCWSTR strField)
+{
+    LPITEMIDLIST ret = NULL;
+
+    // Ensure it really is an IDLIST-formatted parameter
+    // Format for IDLIST params: ":pid:shared"
+    if (*strField != L':')
+        return NULL;
+
+    HANDLE hData = (HANDLE) StrToIntW(strField + 1);
+    PWSTR strSecond = StrChrW(strField + 1, L':');
+
+    if (strSecond)
+    {
+        int pid = StrToIntW(strSecond + 1);
+        void* pvShared = SHLockShared(hData, pid);
+        if (pvShared)
+        {
+            ret = ILClone((LPCITEMIDLIST) pvShared);
+            SHUnlockShared(pvShared);
+            SHFreeShared(hData, pid);
+        }
+    }
+    return ret;
+}
+
 static DWORD Dde_OnExecute(HCONV hconv, HSZ hszTopic, HDDEDATA hdata)
 {
     WCHAR szTopic[MAX_PATH];
@@ -92,7 +132,7 @@ static DWORD Dde_OnExecute(HCONV hconv, HSZ hszTopic, HDDEDATA hdata)
 
     DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
 
-    pszCommand = (WCHAR*)DdeAccessData(hdata, NULL);
+    pszCommand = (WCHAR*) DdeAccessData(hdata, NULL);
     if (!pszCommand)
         return DDE_FNOTPROCESSED;
 
@@ -103,15 +143,139 @@ static DWORD Dde_OnExecute(HCONV hconv, HSZ hszTopic, HDDEDATA hdata)
     DbgPrint("Dde_OnExecute: hconv=%p, topic=%S, command=%S\n", hconv, szTopic, pszCommand);
 
     /*
-    
     [ViewFolder("%l", %I, %S)]    -- Open a folder in standard mode
     [ExploreFolder("%l", %I, %S)] -- Open a folder in "explore" mode (file tree is shown to the left by default)
     [FindFolder("%l", %I)]        -- Open a folder in "find" mode (search panel is shown to the left by default)
     [ShellFile("%1","%1",%S)]     -- Execute the contents of the specified .SCF file
-    
+
+    Approximate grammar (Upper names define rules, <lower> names define terminals, single-quotes are literals):
+
+        Rules
+            Command = ('[' Function ']') | Function
+            Function = <identifier> '(' Parameters ')'
+            Parameters = (<quoted-string> (',' <idlist> (',' <number>)?)?)?
+
+        Terminals
+            <identifier> =  [a-zA-Z]+
+            <quoted-string> = \"([^\"]|\\.)\"
+            <idlist> = \:[0-9]+\:[0-9]+
+            <number> = [0-9]+
     */
 
-    return DDE_FACK;
+    WCHAR Command[MAX_PATH] = L"";
+    WCHAR Path[MAX_PATH] = L"";
+    LPITEMIDLIST IdList = NULL;
+    INT UnknownParameter = 0;
+
+    // Simplified parsing (assumes the command will not be TOO broken):
+
+    PWSTR cmd = szCommand;
+    //    1. if starts with [, skip first char
+    if (*cmd == L'[')
+        cmd++;
+
+    if (*cmd == L']')
+    {
+        ERR("Empty command. Nothing to run.\n");
+        return DDE_FNOTPROCESSED;
+    }
+
+    // Read until first (, and take text before ( as command name
+    {
+        PWSTR cmdEnd = StrChrW(cmd, L'(');
+
+        if (!cmdEnd)
+        {
+            ERR("Could not find '('. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        *cmdEnd = 0;
+
+        StringCchCopy(Command, _countof(Command), cmd);
+
+        cmd = cmdEnd + 1;
+    }
+
+    // Read first param after (, expecting quoted string
+    if (*cmd != L')')
+    {
+        // Copy unescaped string
+        PWSTR dst = Path;
+        BOOL isQuote = FALSE;
+
+        PWSTR arg = cmd;
+
+        while (*arg && (isQuote || *arg != L','))
+        {
+            if (*arg == L'"')
+            {
+                isQuote = !isQuote;
+                if (isQuote && arg != cmd) // do not copy the " at the beginning of the string
+                {
+                    *(dst++) = L'"';
+                }
+            }
+            else
+            {
+                *(dst++) = *arg;
+            }
+
+            arg++;
+        }
+
+        cmd = arg + 1;
+
+        while (*cmd == L' ')
+            cmd++;
+    }
+
+    // Read second param, expecting an idlist in shared memory
+    if (*cmd != L')')
+    {
+        if (*cmd != ':')
+        {
+            ERR("Expected ':'. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        PWSTR idlistEnd = StrChrW(cmd, L',');
+
+        if (!idlistEnd)
+            idlistEnd = StrChrW(cmd, L')');
+
+        if (!idlistEnd)
+        {
+            ERR("Expected ',' or ')'. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        IdList = _ILReadFromSharedMemory(cmd);
+
+        cmd = idlistEnd + 1;
+    }
+
+    // Read third param, expecting an integer
+    if (*cmd != L')')
+    {
+        UnknownParameter = StrToIntW(cmd);
+    }
+
+    DbgPrint("Parse end: cmd=%S, S=%d, pidl=%p, path=%S\n", Command, UnknownParameter, IdList, Path);
+
+    // Find handler in list
+    for (int i = 0; i < HandlerListLength; i++)
+    {
+        DDECommandHandler & handler = HandlerList[i];
+        if (StrCmpW(handler.Command, Command) == 0)
+        {
+            return handler.Handler(Command, Path, IdList, UnknownParameter);
+        }
+    }
+
+    // No handler found
+    ERR("Unknown command %S\n", Command);
+    return DDE_FNOTPROCESSED;
 }
 
 static void Dde_OnDisconnect(HCONV hconv)
@@ -132,26 +296,26 @@ static HDDEDATA CALLBACK DdeCallback(
     switch (uType)
     {
     case XTYP_CONNECT:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnConnect(hsz1, hsz2);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnConnect(hsz1, hsz2);
     case XTYP_CONNECT_CONFIRM:
         Dde_OnConnectConfirm(hconv, hsz1, hsz2);
         return NULL;
     case XTYP_WILDCONNECT:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnWildConnect(hsz1, hsz2);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnWildConnect(hsz1, hsz2);
     case XTYP_REQUEST:
         return Dde_OnRequest(uFmt, hconv, hsz1, hsz2);
     case XTYP_EXECUTE:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnExecute(hconv, hsz1, hdata);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnExecute(hconv, hsz1, hdata);
     case XTYP_DISCONNECT:
         Dde_OnDisconnect(hconv);
         return NULL;
+    case XTYP_REGISTER:
+        return NULL;
     default:
         DbgPrint("DdeCallback: unknown uType=%d\n", uType);
-    case XTYP_REGISTER:
         return NULL;
     }
 }
-
 /*************************************************************************
  * ShellDDEInit (SHELL32.@)
  *
@@ -168,7 +332,7 @@ EXTERN_C void WINAPI ShellDDEInit(BOOL bInit)
 {
     DbgPrint("ShellDDEInit bInit = %s\n", bInit ? "TRUE" : "FALSE");
 
-    if (bInit)
+    if (bInit && !bInitialized)
     {
         DdeInitializeW(&dwDDEInst, DdeCallback, CBF_FAIL_ADVISES | CBF_FAIL_POKES, 0);
 
@@ -178,19 +342,67 @@ EXTERN_C void WINAPI ShellDDEInit(BOOL bInit)
         hszAppProperties = DdeCreateStringHandleW(dwDDEInst, L"AppProperties", CP_WINUNICODE);
         hszFolders = DdeCreateStringHandleW(dwDDEInst, L"Folders", CP_WINUNICODE);
 
-        DdeNameService(dwDDEInst, hszFolders, 0, DNS_FILTEROFF);
+        if (hszProgmanTopic && hszProgmanService &&
+            hszShell && hszAppProperties && hszFolders &&
+            DdeNameService(dwDDEInst, hszFolders, 0, DNS_REGISTER) &&
+            DdeNameService(dwDDEInst, hszProgmanService, 0, DNS_REGISTER) &&
+            DdeNameService(dwDDEInst, hszShell, 0, DNS_REGISTER))
+        {
+            bInitialized = TRUE;
+        }
     }
-    else
+    else if (!bInit && bInitialized)
     {
         /* unregister all services */
         DdeNameService(dwDDEInst, 0, 0, DNS_UNREGISTER);
 
-        DdeFreeStringHandle(dwDDEInst, hszFolders);
+        if (hszFolders)
-        DdeFreeStringHandle(dwDDEInst, hszAppProperties);
+            DdeFreeStringHandle(dwDDEInst, hszFolders);
-        DdeFreeStringHandle(dwDDEInst, hszShell);
+        if (hszAppProperties)
-        DdeFreeStringHandle(dwDDEInst, hszProgmanService);
+            DdeFreeStringHandle(dwDDEInst, hszAppProperties);
-        DdeFreeStringHandle(dwDDEInst, hszProgmanTopic);
+        if (hszShell)
+            DdeFreeStringHandle(dwDDEInst, hszShell);
+        if (hszProgmanService)
+            DdeFreeStringHandle(dwDDEInst, hszProgmanService);
+        if (hszProgmanTopic)
+            DdeFreeStringHandle(dwDDEInst, hszProgmanTopic);
 
         DdeUninitialize(dwDDEInst);
+
+        bInitialized = FALSE;
     }
 }
+
+static DWORD CALLBACK DDE_OnViewFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FACK;
+}
+
+static DWORD CALLBACK DDW_OnExploreFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FACK;
+}
+
+static DWORD CALLBACK DDE_OnFindFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FNOTPROCESSED;
+}
+
+static DWORD CALLBACK DDE_OnShellFile(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FNOTPROCESSED;
+}
+
+DDECommandHandler HandlerList [] = {
+
+        { L"ViewFolder", DDE_OnViewFolder },
+        { L"ExploreFolder", DDW_OnExploreFolder },
+        { L"FindFolder", DDE_OnFindFolder },
+        { L"ShellFile", DDE_OnShellFile }
+};
+
+const int HandlerListLength = _countof(HandlerList);

dll/win32/shell32/dde.cpp

@@ -19,69 +19,268 @@
  */
 
 #include "precomp.h"
+#include <ddeml.h>
+#include <strsafe.h>
+#include <shlwapi_undoc.h>
 
-WINE_DEFAULT_DEBUG_CHANNEL(shell);
+WINE_DEFAULT_DEBUG_CHANNEL(shelldde);
+
+typedef DWORD(CALLBACK * pfnCommandHandler)(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS);
+
+struct DDECommandHandler
+{
+    WCHAR Command[32];
+    pfnCommandHandler Handler;
+};
+
+extern DDECommandHandler HandlerList [];
+extern const int HandlerListLength;
+
+/* DDE Instance ID */
+static DWORD dwDDEInst;
 
 /* String handles */
 static HSZ hszProgmanTopic;
 static HSZ hszProgmanService;
-static HSZ hszAsterisk;
 static HSZ hszShell;
 static HSZ hszAppProperties;
 static HSZ hszFolders;
-/* DDE Instance ID */
-static DWORD dwDDEInst;
 
+static BOOL bInitialized;
 
-static BOOL __inline Dde_OnConnect(HSZ hszTopic, HSZ hszService)
+static BOOL Dde_OnConnect(HSZ hszTopic, HSZ hszService)
 {
-    if ((hszTopic == hszProgmanTopic) && (hszService == hszProgmanService))
+    WCHAR szTopic[MAX_PATH];
-        return TRUE;
+    WCHAR szService[MAX_PATH];
-    if ((hszTopic == hszProgmanTopic) && (hszService == hszAppProperties))
+
-        return TRUE;
+    DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
-    if ((hszTopic == hszShell) && (hszService == hszFolders))
+    DdeQueryStringW(dwDDEInst, hszService, szService, _countof(szService), CP_WINUNICODE);
-        return TRUE;
+
-    if ((hszTopic == hszShell) && (hszService == hszAppProperties))
+    DbgPrint("Dde_OnConnect: topic=%S, service=%S\n", szTopic, szService);
-        return TRUE;
+
+    return TRUE;
+}
+
+static void Dde_OnConnectConfirm(HCONV hconv, HSZ hszTopic, HSZ hszService)
+{
+    WCHAR szTopic[MAX_PATH];
+    WCHAR szService[MAX_PATH];
+
+    DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
+    DdeQueryStringW(dwDDEInst, hszService, szService, _countof(szService), CP_WINUNICODE);
+
+    DbgPrint("Dde_OnConnectConfirm: hconv=%p, topic=%S, service=%S\n", hconv, szTopic, szService);
+}
+
+static BOOL Dde_OnWildConnect(HSZ hszTopic, HSZ hszService)
+{
+    WCHAR szTopic[MAX_PATH];
+    WCHAR szService[MAX_PATH];
+
+    DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
+    DdeQueryStringW(dwDDEInst, hszService, szService, _countof(szService), CP_WINUNICODE);
+
+    DbgPrint("Dde_OnWildConnect: topic=%S, service=%S\n", szTopic, szService);
+
     return FALSE;
 }
 
-static void __inline Dde_OnConnectConfirm(HCONV hconv, HSZ hszTopic, HSZ hszService)
+static HDDEDATA Dde_OnRequest(UINT uFmt, HCONV hconv, HSZ hszTopic, HSZ hszItem)
 {
-    FIXME("stub\n");
+    WCHAR szTopic[MAX_PATH];
-}
+    WCHAR szItem[MAX_PATH];
 
-static BOOL __inline Dde_OnWildConnect(HSZ hszTopic, HSZ hszService)
+    DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
-{
+    DdeQueryStringW(dwDDEInst, hszItem, szItem, _countof(szItem), CP_WINUNICODE);
-    FIXME("stub\n");
+
-    return FALSE;
+    DbgPrint("Dde_OnRequest: uFmt=%d, hconv=%p, topic=%S, item=%S\n", hconv, szTopic, szItem);
-}
 
-static HDDEDATA __inline Dde_OnRequest(UINT uFmt, HCONV hconv, HSZ hszTopic,
-                                     HSZ hszItem)
-{
-    FIXME("stub\n");
     return NULL;
 }
 
-static DWORD __inline Dde_OnExecute(HCONV hconv, HSZ hszTopic, HDDEDATA hdata)
+static LPITEMIDLIST _ILReadFromSharedMemory(PCWSTR strField)
 {
-    BYTE * pszCommand;
+    LPITEMIDLIST ret = NULL;
 
-    pszCommand = DdeAccessData(hdata, NULL);
+    // Ensure it really is an IDLIST-formatted parameter
+    // Format for IDLIST params: ":pid:shared"
+    if (*strField != L':')
+        return NULL;
+
+    HANDLE hData = (HANDLE) StrToIntW(strField + 1);
+    PWSTR strSecond = StrChrW(strField + 1, L':');
+
+    if (strSecond)
+    {
+        int pid = StrToIntW(strSecond + 1);
+        void* pvShared = SHLockShared(hData, pid);
+        if (pvShared)
+        {
+            ret = ILClone((LPCITEMIDLIST) pvShared);
+            SHUnlockShared(pvShared);
+            SHFreeShared(hData, pid);
+        }
+    }
+    return ret;
+}
+
+static DWORD Dde_OnExecute(HCONV hconv, HSZ hszTopic, HDDEDATA hdata)
+{
+    WCHAR szTopic[MAX_PATH];
+    WCHAR szCommand[MAX_PATH];
+    WCHAR *pszCommand;
+
+    DdeQueryStringW(dwDDEInst, hszTopic, szTopic, _countof(szTopic), CP_WINUNICODE);
+
+    pszCommand = (WCHAR*) DdeAccessData(hdata, NULL);
     if (!pszCommand)
         return DDE_FNOTPROCESSED;
 
-    FIXME("stub: %s\n", pszCommand);
+    StringCchCopyW(szCommand, _countof(szCommand), pszCommand);
 
     DdeUnaccessData(hdata);
 
+    DbgPrint("Dde_OnExecute: hconv=%p, topic=%S, command=%S\n", hconv, szTopic, pszCommand);
+
+    /*
+    [ViewFolder("%l", %I, %S)]    -- Open a folder in standard mode
+    [ExploreFolder("%l", %I, %S)] -- Open a folder in "explore" mode (file tree is shown to the left by default)
+    [FindFolder("%l", %I)]        -- Open a folder in "find" mode (search panel is shown to the left by default)
+    [ShellFile("%1","%1",%S)]     -- Execute the contents of the specified .SCF file
+
+    Approximate grammar (Upper names define rules, <lower> names define terminals, single-quotes are literals):
+
+        Rules
+            Command = ('[' Function ']') | Function
+            Function = <identifier> '(' Parameters ')'
+            Parameters = (<quoted-string> (',' <idlist> (',' <number>)?)?)?
+
+        Terminals
+            <identifier> =  [a-zA-Z]+
+            <quoted-string> = \"([^\"]|\\.)\"
+            <idlist> = \:[0-9]+\:[0-9]+
+            <number> = [0-9]+
+    */
+
+    WCHAR Command[MAX_PATH] = L"";
+    WCHAR Path[MAX_PATH] = L"";
+    LPITEMIDLIST IdList = NULL;
+    INT UnknownParameter = 0;
+
+    // Simplified parsing (assumes the command will not be TOO broken):
+
+    PWSTR cmd = szCommand;
+    //    1. if starts with [, skip first char
+    if (*cmd == L'[')
+        cmd++;
+
+    if (*cmd == L']')
+    {
+        ERR("Empty command. Nothing to run.\n");
+        return DDE_FNOTPROCESSED;
+    }
+
+    // Read until first (, and take text before ( as command name
+    {
+        PWSTR cmdEnd = StrChrW(cmd, L'(');
+
+        if (!cmdEnd)
+        {
+            ERR("Could not find '('. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        *cmdEnd = 0;
+
+        StringCchCopy(Command, _countof(Command), cmd);
+
+        cmd = cmdEnd + 1;
+    }
+
+    // Read first param after (, expecting quoted string
+    if (*cmd != L')')
+    {
+        // Copy unescaped string
+        PWSTR dst = Path;
+        BOOL isQuote = FALSE;
+
+        PWSTR arg = cmd;
+
+        while (*arg && (isQuote || *arg != L','))
+        {
+            if (*arg == L'"')
+            {
+                isQuote = !isQuote;
+                if (isQuote && arg != cmd) // do not copy the " at the beginning of the string
+                {
+                    *(dst++) = L'"';
+                }
+            }
+            else
+            {
+                *(dst++) = *arg;
+            }
+
+            arg++;
+        }
+
+        cmd = arg + 1;
+
+        while (*cmd == L' ')
+            cmd++;
+    }
+
+    // Read second param, expecting an idlist in shared memory
+    if (*cmd != L')')
+    {
+        if (*cmd != ':')
+        {
+            ERR("Expected ':'. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        PWSTR idlistEnd = StrChrW(cmd, L',');
+
+        if (!idlistEnd)
+            idlistEnd = StrChrW(cmd, L')');
+
+        if (!idlistEnd)
+        {
+            ERR("Expected ',' or ')'. Invalid command.\n");
+            return DDE_FNOTPROCESSED;
+        }
+
+        IdList = _ILReadFromSharedMemory(cmd);
+
+        cmd = idlistEnd + 1;
+    }
+
+    // Read third param, expecting an integer
+    if (*cmd != L')')
+    {
+        UnknownParameter = StrToIntW(cmd);
+    }
+
+    DbgPrint("Parse end: cmd=%S, S=%d, pidl=%p, path=%S\n", Command, UnknownParameter, IdList, Path);
+
+    // Find handler in list
+    for (int i = 0; i < HandlerListLength; i++)
+    {
+        DDECommandHandler & handler = HandlerList[i];
+        if (StrCmpW(handler.Command, Command) == 0)
+        {
+            return handler.Handler(Command, Path, IdList, UnknownParameter);
+        }
+    }
+
+    // No handler found
+    ERR("Unknown command %S\n", Command);
     return DDE_FNOTPROCESSED;
 }
 
-static void __inline Dde_OnDisconnect(HCONV hconv)
+static void Dde_OnDisconnect(HCONV hconv)
 {
-    FIXME("stub\n");
+    DbgPrint("Dde_OnDisconnect: hconv=%p\n", hconv);
 }
 
 static HDDEDATA CALLBACK DdeCallback(
@@ -97,24 +296,26 @@ static HDDEDATA CALLBACK DdeCallback(
     switch (uType)
     {
     case XTYP_CONNECT:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnConnect(hsz1, hsz2);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnConnect(hsz1, hsz2);
     case XTYP_CONNECT_CONFIRM:
         Dde_OnConnectConfirm(hconv, hsz1, hsz2);
         return NULL;
     case XTYP_WILDCONNECT:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnWildConnect(hsz1, hsz2);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnWildConnect(hsz1, hsz2);
     case XTYP_REQUEST:
         return Dde_OnRequest(uFmt, hconv, hsz1, hsz2);
     case XTYP_EXECUTE:
-        return (HDDEDATA)(DWORD_PTR)Dde_OnExecute(hconv, hsz1, hdata);
+        return (HDDEDATA) (DWORD_PTR) Dde_OnExecute(hconv, hsz1, hdata);
     case XTYP_DISCONNECT:
         Dde_OnDisconnect(hconv);
         return NULL;
+    case XTYP_REGISTER:
+        return NULL;
     default:
+        DbgPrint("DdeCallback: unknown uType=%d\n", uType);
         return NULL;
     }
 }
-
 /*************************************************************************
  * ShellDDEInit (SHELL32.@)
  *
@@ -129,42 +330,95 @@ static HDDEDATA CALLBACK DdeCallback(
  */
 EXTERN_C void WINAPI ShellDDEInit(BOOL bInit)
 {
-    TRACE("bInit = %s\n", bInit ? "TRUE" : "FALSE");
+    DbgPrint("ShellDDEInit bInit = %s\n", bInit ? "TRUE" : "FALSE");
 
-    if (bInit)
+    if (bInit && !bInitialized)
     {
-        static const WCHAR wszProgman[] = {'P','r','o','g','m','a','n',0};
-        static const WCHAR wszAsterisk[] = {'*',0};
-        static const WCHAR wszShell[] = {'S','h','e','l','l',0};
-        static const WCHAR wszAppProperties[] =
-            {'A','p','p','P','r','o','p','e','r','t','i','e','s',0};
-        static const WCHAR wszFolders[] = {'F','o','l','d','e','r','s',0};
-
         DdeInitializeW(&dwDDEInst, DdeCallback, CBF_FAIL_ADVISES | CBF_FAIL_POKES, 0);
 
-        hszProgmanTopic = DdeCreateStringHandleW(dwDDEInst, wszProgman, CP_WINUNICODE);
+        hszProgmanTopic = DdeCreateStringHandleW(dwDDEInst, L"Progman", CP_WINUNICODE);
-        hszProgmanService = DdeCreateStringHandleW(dwDDEInst, wszProgman, CP_WINUNICODE);
+        hszProgmanService = DdeCreateStringHandleW(dwDDEInst, L"Progman", CP_WINUNICODE);
-        hszAsterisk = DdeCreateStringHandleW(dwDDEInst, wszAsterisk, CP_WINUNICODE);
+        hszShell = DdeCreateStringHandleW(dwDDEInst, L"Shell", CP_WINUNICODE);
-        hszShell = DdeCreateStringHandleW(dwDDEInst, wszShell, CP_WINUNICODE);
+        hszAppProperties = DdeCreateStringHandleW(dwDDEInst, L"AppProperties", CP_WINUNICODE);
-        hszAppProperties = DdeCreateStringHandleW(dwDDEInst, wszAppProperties, CP_WINUNICODE);
+        hszFolders = DdeCreateStringHandleW(dwDDEInst, L"Folders", CP_WINUNICODE);
-        hszFolders = DdeCreateStringHandleW(dwDDEInst, wszFolders, CP_WINUNICODE);
 
-        DdeNameService(dwDDEInst, hszFolders, 0, DNS_REGISTER);
+        if (hszProgmanTopic && hszProgmanService &&
-        DdeNameService(dwDDEInst, hszProgmanService, 0, DNS_REGISTER);
+            hszShell && hszAppProperties && hszFolders &&
-        DdeNameService(dwDDEInst, hszShell, 0, DNS_REGISTER);
+            DdeNameService(dwDDEInst, hszFolders, 0, DNS_REGISTER) &&
+            DdeNameService(dwDDEInst, hszProgmanService, 0, DNS_REGISTER) &&
+            DdeNameService(dwDDEInst, hszShell, 0, DNS_REGISTER))
+        {
+            bInitialized = TRUE;
+        }
     }
-    else
+    else if (!bInit && bInitialized)
     {
         /* unregister all services */
         DdeNameService(dwDDEInst, 0, 0, DNS_UNREGISTER);
 
-        DdeFreeStringHandle(dwDDEInst, hszFolders);
+        if (hszFolders)
-        DdeFreeStringHandle(dwDDEInst, hszAppProperties);
+            DdeFreeStringHandle(dwDDEInst, hszFolders);
-        DdeFreeStringHandle(dwDDEInst, hszShell);
+        if (hszAppProperties)
-        DdeFreeStringHandle(dwDDEInst, hszAsterisk);
+            DdeFreeStringHandle(dwDDEInst, hszAppProperties);
-        DdeFreeStringHandle(dwDDEInst, hszProgmanService);
+        if (hszShell)
-        DdeFreeStringHandle(dwDDEInst, hszProgmanTopic);
+            DdeFreeStringHandle(dwDDEInst, hszShell);
+        if (hszProgmanService)
+            DdeFreeStringHandle(dwDDEInst, hszProgmanService);
+        if (hszProgmanTopic)
+            DdeFreeStringHandle(dwDDEInst, hszProgmanTopic);
 
         DdeUninitialize(dwDDEInst);
+
+        bInitialized = FALSE;
     }
 }
+
+static DWORD CALLBACK DDE_OnViewFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    if (!pidl)
+        pidl = ILCreateFromPathW(strPath);
+
+    if (!pidl)
+        return DDE_FNOTPROCESSED;
+
+    if (FAILED(SHOpenNewFrame(pidl, NULL, 0, 0)))
+        return DDE_FNOTPROCESSED;
+
+    return DDE_FACK;
+}
+
+static DWORD CALLBACK DDW_OnExploreFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    if (!pidl)
+        pidl = ILCreateFromPathW(strPath);
+
+    if (!pidl)
+        return DDE_FNOTPROCESSED;
+
+    if (FAILED(SHOpenNewFrame(pidl, NULL, 0, SH_EXPLORER_CMDLINE_FLAG_E)))
+        return DDE_FNOTPROCESSED;
+
+    return DDE_FACK;
+}
+
+static DWORD CALLBACK DDE_OnFindFolder(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FNOTPROCESSED;
+}
+
+static DWORD CALLBACK DDE_OnShellFile(PWSTR strCommand, PWSTR strPath, LPITEMIDLIST pidl, INT unkS)
+{
+    UNIMPLEMENTED;
+    return DDE_FNOTPROCESSED;
+}
+
+DDECommandHandler HandlerList [] = {
+
+        { L"ViewFolder", DDE_OnViewFolder },
+        { L"ExploreFolder", DDW_OnExploreFolder },
+        { L"FindFolder", DDE_OnFindFolder },
+        { L"ShellFile", DDE_OnShellFile }
+};
+
+const int HandlerListLength = _countof(HandlerList);