dlls/oleaut32/dispatch.c

   1 /**
   2  * Dispatch API functions
   3  *
   4  * Copyright 2000  Francois Jacques, Macadamian Technologies Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  *
  20  */
  21
  22 #include "config.h"
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <stdarg.h>
  27 #include <stdio.h>
  28 #include <ctype.h>
  29
  30 #define COBJMACROS
  31
  32 #include "windef.h"
  33 #include "winbase.h"
  34 #include "objbase.h"
  35 #include "oleauto.h"
  36 #include "winerror.h"
  37
  38 #include "wine/debug.h"
  39
  40 WINE_DEFAULT_DEBUG_CHANNEL(ole);
  41
  42 static IDispatch * WINAPI StdDispatch_Construct(IUnknown * punkOuter, void * pvThis, ITypeInfo * pTypeInfo);
  43
  44 /******************************************************************************
  45  *              DispInvoke (OLEAUT32.30)
  46  *
  47  * Call an object method using the information from its type library.
  48  *
  49  * RETURNS
  50  *  Success: S_OK.
  51  *  Failure: Returns DISP_E_EXCEPTION and updates pexcepinfo if an exception occurs.
  52  *           DISP_E_BADPARAMCOUNT if the number of parameters is incorrect.
  53  *           DISP_E_MEMBERNOTFOUND if the method does not exist.
  54  *           puArgErr is updated if a parameter error (see notes) occurs.
  55  *           Otherwise, returns the result of calling ITypeInfo_Invoke().
  56  *
  57  * NOTES
  58  *  Parameter errors include the following:
  59  *| DISP_E_BADVARTYPE
  60  *| E_INVALIDARG            An argument was invalid
  61  *| DISP_E_TYPEMISMATCH,
  62  *| DISP_E_OVERFLOW         An argument was valid but could not be coerced
  63  *| DISP_E_PARAMNOTOPTIONAL A non optional parameter was not passed
  64  *| DISP_E_PARAMNOTFOUND    A parameter was passed that was not expected by the method
  65  *  This call defers to ITypeInfo_Invoke().
  66  */
  67 HRESULT WINAPI DispInvoke(
  68         VOID       *_this,        /* [in] Object to call method on */
  69         ITypeInfo  *ptinfo,       /* [in] Object type info */
  70         DISPID      dispidMember, /* [in] DISPID of the member (e.g. from GetIDsOfNames()) */
  71         USHORT      wFlags,       /* [in] Kind of method call (DISPATCH_ flags from "oaidl.h") */
  72         DISPPARAMS *pparams,      /* [in] Array of method arguments */
  73         VARIANT    *pvarResult,   /* [out] Destination for the result of the call */
  74         EXCEPINFO  *pexcepinfo,   /* [out] Destination for exception information */
  75         UINT       *puArgErr)     /* [out] Destination for bad argument */
  76 {
  77     TRACE("\n");
  78
  79     return ITypeInfo_Invoke(ptinfo, _this, dispidMember, wFlags,
  80                             pparams, pvarResult, pexcepinfo, puArgErr);
  81 }
  82
  83 /******************************************************************************
  84  *              DispGetIDsOfNames (OLEAUT32.29)
  85  *
  86  * Convert a set of parameter names to DISPIDs for DispInvoke().
  87  *
  88  * RETURNS
  89  *  Success: S_OK.
  90  *  Failure: An HRESULT error code.
  91  *
  92  * NOTES
  93  *  This call defers to ITypeInfo_GetIDsOfNames(). The ITypeInfo interface passed
  94  *  as ptinfo contains the information to map names to DISPIDs.
  95  */
  96 HRESULT WINAPI DispGetIDsOfNames(
  97         ITypeInfo  *ptinfo,    /* [in] Object's type info */
  98         OLECHAR   **rgszNames, /* [in] Array of names to get DISPIDs for */
  99         UINT        cNames,    /* [in] Number of names in rgszNames */
 100         DISPID     *rgdispid)  /* [out] Destination for converted DISPIDs */
 101 {
 102     return ITypeInfo_GetIDsOfNames(ptinfo, rgszNames, cNames, rgdispid);
 103 }
 104
 105 /******************************************************************************
 106  *              DispGetParam (OLEAUT32.28)
 107  *
 108  * Retrieve a parameter from a DISPPARAMS structure and coerce it to the
 109  * specified variant type.
 110  *
 111  * NOTES
 112  *  Coercion is done using system (0) locale.
 113  *
 114  * RETURNS
 115  *  Success: S_OK.
 116  *  Failure: DISP_E_PARAMNOTFOUND, if position is invalid. or
 117  *           DISP_E_TYPEMISMATCH, if the coercion failed. puArgErr is
 118  *           set to the index of the argument in pdispparams.
 119  */
 120 HRESULT WINAPI DispGetParam(
 121         DISPPARAMS *pdispparams, /* [in] Parameter list */
 122         UINT        position,    /* [in] Position of parameter to coerce in pdispparams */
 123         VARTYPE     vtTarg,      /* [in] Type of value to coerce to */
 124         VARIANT    *pvarResult,  /* [out] Destination for resulting variant */
 125         UINT       *puArgErr)    /* [out] Destination for error code */
 126 {
 127     /* position is counted backwards */
 128     UINT pos;
 129     HRESULT hr;
 130
 131     TRACE("position=%d, cArgs=%d, cNamedArgs=%d\n",
 132           position, pdispparams->cArgs, pdispparams->cNamedArgs);
 133     if (position < pdispparams->cArgs) {
 134       /* positional arg? */
 135       pos = pdispparams->cArgs - position - 1;
 136     } else {
 137       /* FIXME: is this how to handle named args? */
 138       for (pos=0; pos<pdispparams->cNamedArgs; pos++)
 139         if (pdispparams->rgdispidNamedArgs[pos] == position) break;
 140
 141       if (pos==pdispparams->cNamedArgs)
 142         return DISP_E_PARAMNOTFOUND;
 143     }
 144     hr = VariantChangeType(pvarResult,
 145                            &pdispparams->rgvarg[pos],
 146                            0, vtTarg);
 147     if (hr == DISP_E_TYPEMISMATCH) *puArgErr = pos;
 148     return hr;
 149 }
 150
 151 /******************************************************************************
 152  * CreateStdDispatch [OLEAUT32.32]
 153  *
 154  * Create and return a standard IDispatch object.
 155  *
 156  * RETURNS
 157  *  Success: S_OK. ppunkStdDisp contains the new object.
 158  *  Failure: An HRESULT error code.
 159  *
 160  * NOTES
 161  *  Outer unknown appears to be completely ignored.
 162  */
 163 HRESULT WINAPI CreateStdDispatch(
 164         IUnknown* punkOuter,
 165         void* pvThis,
 166         ITypeInfo* ptinfo,
 167         IUnknown** ppunkStdDisp)
 168 {
 169     TRACE("(%p, %p, %p, %p)\n", punkOuter, pvThis, ptinfo, ppunkStdDisp);
 170
 171     *ppunkStdDisp = (LPUNKNOWN)StdDispatch_Construct(punkOuter, pvThis, ptinfo);
 172     if (!*ppunkStdDisp)
 173         return E_OUTOFMEMORY;
 174     return S_OK;
 175 }
 176
 177
 178 /******************************************************************************
 179  * IDispatch {OLEAUT32}
 180  *
 181  * NOTES
 182  *  The IDispatch interface provides a single interface to dispatch method calls,
 183  *  regardless of whether the object to be called is in or out of process,
 184  *  local or remote (e.g. being called over a network). This interface is late-bound
 185  *  (linked at run-time), as opposed to early-bound (linked at compile time).
 186  *
 187  *  The interface is used by objects that wish to called by scripting
 188  *  languages such as VBA, in order to minimise the amount of COM and C/C++
 189  *  knowledge required, or by objects that wish to live out of process from code
 190  *  that will call their methods.
 191  *
 192  *  Method, property and parameter names can be localised. The details required to
 193  *  map names to methods and parameters are collected in a type library, usually
 194  *  output by an IDL compiler using the objects IDL description. This information is
 195  *  accessible programatically through the ITypeLib interface (for a type library),
 196  *  and the ITypeInfo interface (for an object within the type library). Type information
 197  *  can also be created at run-time using CreateDispTypeInfo().
 198  *
 199  * WRAPPERS
 200  *  Instead of using IDispatch directly, there are several wrapper functions available
 201  *  to simplify the process of calling an objects methods through IDispatch.
 202  *
 203  *  A standard implementation of an IDispatch object is created by calling
 204  *  CreateStdDispatch(). Numeric Id values for the parameters and methods (DISPIDs)
 205  *  of an object of interest are retrieved by calling DispGetIDsOfNames(). DispGetParam()
 206  *  retrieves information about a particular parameter. Finally the DispInvoke()
 207  *  function is responsible for actually calling methods on an object.
 208  *
 209  * METHODS
 210  */
 211
 212 typedef struct
 213 {
 214     const IDispatchVtbl *lpVtbl;
 215     void * pvThis;
 216     ITypeInfo * pTypeInfo;
 217     LONG ref;
 218 } StdDispatch;
 219
 220 /******************************************************************************
 221  * IDispatch_QueryInterface {OLEAUT32}
 222  *
 223  * See IUnknown_QueryInterface.
 224  */
 225 static HRESULT WINAPI StdDispatch_QueryInterface(
 226   LPDISPATCH iface,
 227   REFIID riid,
 228   void** ppvObject)
 229 {
 230     StdDispatch *This = (StdDispatch *)iface;
 231     TRACE("(%p)->(%s, %p)\n", iface, debugstr_guid(riid), ppvObject);
 232
 233     if (IsEqualIID(riid, &IID_IDispatch) ||
 234         IsEqualIID(riid, &IID_IUnknown))
 235     {
 236         *ppvObject = (LPVOID)This;
 237         IUnknown_AddRef((LPUNKNOWN)*ppvObject);
 238         return S_OK;
 239     }
 240     return E_NOINTERFACE;
 241 }
 242
 243 /******************************************************************************
 244  * IDispatch_AddRef {OLEAUT32}
 245  *
 246  * See IUnknown_AddRef.
 247  */
 248 static ULONG WINAPI StdDispatch_AddRef(LPDISPATCH iface)
 249 {
 250     StdDispatch *This = (StdDispatch *)iface;
 251     ULONG refCount = InterlockedIncrement(&This->ref);
 252
 253     TRACE("(%p)->(ref before=%u)\n",This, refCount - 1);
 254
 255     return refCount;
 256 }
 257
 258 /******************************************************************************
 259  * IDispatch_Release {OLEAUT32}
 260  *
 261  * See IUnknown_Release.
 262  */
 263 static ULONG WINAPI StdDispatch_Release(LPDISPATCH iface)
 264 {
 265     StdDispatch *This = (StdDispatch *)iface;
 266     ULONG refCount = InterlockedDecrement(&This->ref);
 267
 268     TRACE("(%p)->(ref before=%u)\n", This, refCount + 1);
 269
 270     if (!refCount)
 271     {
 272         ITypeInfo_Release(This->pTypeInfo);
 273         CoTaskMemFree(This);
 274     }
 275
 276     return refCount;
 277 }
 278
 279 /******************************************************************************
 280  * IDispatch_GetTypeInfoCount {OLEAUT32}
 281  *
 282  * Get the count of type information in an IDispatch interface.
 283  *
 284  * PARAMS
 285  *  iface   [I] IDispatch interface
 286  *  pctinfo [O] Destination for the count
 287  *
 288  * RETURNS
 289  *  Success: S_OK. pctinfo is updated with the count. This is always 1 if
 290  *           the object provides type information, and 0 if it does not.
 291  *  Failure: E_NOTIMPL. The object does not provide type information.
 292  *
 293  * NOTES
 294  *  See IDispatch() and IDispatch_GetTypeInfo().
 295  */
 296 static HRESULT WINAPI StdDispatch_GetTypeInfoCount(LPDISPATCH iface, UINT * pctinfo)
 297 {
 298     StdDispatch *This = (StdDispatch *)iface;
 299     TRACE("(%p)\n", pctinfo);
 300
 301     *pctinfo = This->pTypeInfo ? 1 : 0;
 302     return S_OK;
 303 }
 304
 305 /******************************************************************************
 306  * IDispatch_GetTypeInfo {OLEAUT32}
 307  *
 308  * Get type information from an IDispatch interface.
 309  *
 310  * PARAMS
 311  *  iface   [I] IDispatch interface
 312  *  iTInfo  [I] Index of type information.
 313  *  lcid    [I] Locale of the type information to get
 314  *  ppTInfo [O] Destination for the ITypeInfo object
 315  *
 316  * RETURNS
 317  *  Success: S_OK. ppTInfo is updated with the objects type information
 318  *  Failure: DISP_E_BADINDEX, if iTInfo is any value other than 0.
 319  *
 320  * NOTES
 321  *  See IDispatch.
 322  */
 323 static HRESULT WINAPI StdDispatch_GetTypeInfo(LPDISPATCH iface, UINT iTInfo, LCID lcid, ITypeInfo** ppTInfo)
 324 {
 325     StdDispatch *This = (StdDispatch *)iface;
 326     TRACE("(%d, %x, %p)\n", iTInfo, lcid, ppTInfo);
 327
 328     *ppTInfo = NULL;
 329     if (iTInfo != 0)
 330         return DISP_E_BADINDEX;
 331
 332     if (This->pTypeInfo)
 333     {
 334       *ppTInfo = This->pTypeInfo;
 335       ITypeInfo_AddRef(*ppTInfo);
 336     }
 337     return S_OK;
 338 }
 339
 340 /******************************************************************************
 341  * IDispatch_GetIDsOfNames {OLEAUT32}
 342  *
 343  * Convert a methods name and an optional set of parameter names into DISPIDs
 344  * for passing to IDispatch_Invoke().
 345  *
 346  * PARAMS
 347  *  iface     [I] IDispatch interface
 348  *  riid      [I] Reserved, set to IID_NULL
 349  *  rgszNames [I] Name to convert
 350  *  cNames    [I] Number of names in rgszNames
 351  *  lcid      [I] Locale of the type information to convert from
 352  *  rgDispId  [O] Destination for converted DISPIDs.
 353  *
 354  * RETURNS
 355  *  Success: S_OK.
 356  *  Failure: DISP_E_UNKNOWNNAME, if any of the names is invalid.
 357  *           DISP_E_UNKNOWNLCID if lcid is invalid.
 358  *           Otherwise, an HRESULT error code.
 359  *
 360  * NOTES
 361  *  This call defers to ITypeInfo_GetIDsOfNames(), using the ITypeInfo object
 362  *  contained within the IDispatch object.
 363  *  The first member of the names list must be a method name. The names following
 364  *  the method name are the parameters for that method.
 365  */
 366 static HRESULT WINAPI StdDispatch_GetIDsOfNames(LPDISPATCH iface, REFIID riid, LPOLESTR * rgszNames, UINT cNames, LCID lcid, DISPID * rgDispId)
 367 {
 368     StdDispatch *This = (StdDispatch *)iface;
 369     TRACE("(%s, %p, %d, 0x%x, %p)\n", debugstr_guid(riid), rgszNames, cNames, lcid, rgDispId);
 370
 371     if (!IsEqualGUID(riid, &IID_NULL))
 372     {
 373         FIXME(" expected riid == IID_NULL\n");
 374         return E_INVALIDARG;
 375     }
 376     return DispGetIDsOfNames(This->pTypeInfo, rgszNames, cNames, rgDispId);
 377 }
 378
 379 /******************************************************************************
 380  * IDispatch_Invoke {OLEAUT32}
 381  *
 382  * Call an object method.
 383  *
 384  * PARAMS
 385  *  iface        [I] IDispatch interface
 386  *  dispIdMember [I] DISPID of the method (from GetIDsOfNames())
 387  *  riid         [I] Reserved, set to IID_NULL
 388  *  lcid         [I] Locale of the type information to convert parameters with
 389  *  wFlags,      [I] Kind of method call (DISPATCH_ flags from "oaidl.h")
 390  *  pDispParams  [I] Array of method arguments
 391  *  pVarResult   [O] Destination for the result of the call
 392  *  pExcepInfo   [O] Destination for exception information
 393  *  puArgErr     [O] Destination for bad argument
 394  *
 395  * RETURNS
 396  *  Success: S_OK.
 397  *  Failure: See DispInvoke() for failure cases.
 398  *
 399  * NOTES
 400  *  See DispInvoke() and IDispatch().
 401  */
 402 static HRESULT WINAPI StdDispatch_Invoke(LPDISPATCH iface, DISPID dispIdMember, REFIID riid, LCID lcid,
 403                                          WORD wFlags, DISPPARAMS * pDispParams, VARIANT * pVarResult,
 404                                          EXCEPINFO * pExcepInfo, UINT * puArgErr)
 405 {
 406     StdDispatch *This = (StdDispatch *)iface;
 407     TRACE("(%d, %s, 0x%x, 0x%x, %p, %p, %p, %p)\n", dispIdMember, debugstr_guid(riid), lcid, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 408
 409     if (!IsEqualGUID(riid, &IID_NULL))
 410     {
 411         FIXME(" expected riid == IID_NULL\n");
 412         return E_INVALIDARG;
 413     }
 414     return DispInvoke(This->pvThis, This->pTypeInfo, dispIdMember, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 415 }
 416
 417 static const IDispatchVtbl StdDispatch_VTable =
 418 {
 419   StdDispatch_QueryInterface,
 420   StdDispatch_AddRef,
 421   StdDispatch_Release,
 422   StdDispatch_GetTypeInfoCount,
 423   StdDispatch_GetTypeInfo,
 424   StdDispatch_GetIDsOfNames,
 425   StdDispatch_Invoke
 426 };
 427
 428 static IDispatch * WINAPI StdDispatch_Construct(
 429   IUnknown * punkOuter,
 430   void * pvThis,
 431   ITypeInfo * pTypeInfo)
 432 {
 433     StdDispatch * pStdDispatch;
 434
 435     pStdDispatch = CoTaskMemAlloc(sizeof(StdDispatch));
 436     if (!pStdDispatch)
 437         return (IDispatch *)pStdDispatch;
 438
 439     pStdDispatch->lpVtbl = &StdDispatch_VTable;
 440     pStdDispatch->pvThis = pvThis;
 441     pStdDispatch->pTypeInfo = pTypeInfo;
 442     pStdDispatch->ref = 1;
 443
 444     /* we keep a reference to the type info so prevent it from
 445      * being destroyed until we are done with it */
 446     ITypeInfo_AddRef(pTypeInfo);
 447
 448     return (IDispatch *)pStdDispatch;
 449 }