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 /******************************************************************************
  43  *              DispInvoke (OLEAUT32.30)
  44  *
  45  * Call an object method using the information from its type library.
  46  *
  47  * RETURNS
  48  *  Success: S_OK.
  49  *  Failure: Returns DISP_E_EXCEPTION and updates pexcepinfo if an exception occurs.
  50  *           DISP_E_BADPARAMCOUNT if the number of parameters is incorrect.
  51  *           DISP_E_MEMBERNOTFOUND if the method does not exist.
  52  *           puArgErr is updated if a parameter error (see notes) occurs.
  53  *           Otherwise, returns the result of calling ITypeInfo_Invoke().
  54  *
  55  * NOTES
  56  *  Parameter errors include the following:
  57  *| DISP_E_BADVARTYPE
  58  *| E_INVALIDARG            An argument was invalid
  59  *| DISP_E_TYPEMISMATCH,
  60  *| DISP_E_OVERFLOW         An argument was valid but could not be coerced
  61  *| DISP_E_PARAMNOTOPTIONAL A non optional parameter was not passed
  62  *| DISP_E_PARAMNOTFOUND    A parameter was passed that was not expected by the method
  63  *  This call defers to ITypeInfo_Invoke().
  64  */
  65 HRESULT WINAPI DispInvoke(
  66         VOID       *_this,        /* [in] Object to call method on */
  67         ITypeInfo  *ptinfo,       /* [in] Object type info */
  68         DISPID      dispidMember, /* [in] DISPID of the member (e.g. from GetIDsOfNames()) */
  69         USHORT      wFlags,       /* [in] Kind of method call (DISPATCH_ flags from "oaidl.h") */
  70         DISPPARAMS *pparams,      /* [in] Array of method arguments */
  71         VARIANT    *pvarResult,   /* [out] Destination for the result of the call */
  72         EXCEPINFO  *pexcepinfo,   /* [out] Destination for exception information */
  73         UINT       *puArgErr)     /* [out] Destination for bad argument */
  74 {
  75     TRACE("\n");
  76
  77     return ITypeInfo_Invoke(ptinfo, _this, dispidMember, wFlags,
  78                             pparams, pvarResult, pexcepinfo, puArgErr);
  79 }
  80
  81 /******************************************************************************
  82  *              DispGetIDsOfNames (OLEAUT32.29)
  83  *
  84  * Convert a set of parameter names to DISPIDs for DispInvoke().
  85  *
  86  * RETURNS
  87  *  Success: S_OK.
  88  *  Failure: An HRESULT error code.
  89  *
  90  * NOTES
  91  *  This call defers to ITypeInfo_GetIDsOfNames(). The ITypeInfo interface passed
  92  *  as ptinfo contains the information to map names to DISPIDs.
  93  */
  94 HRESULT WINAPI DispGetIDsOfNames(
  95         ITypeInfo  *ptinfo,    /* [in] Object's type info */
  96         OLECHAR   **rgszNames, /* [in] Array of names to get DISPIDs for */
  97         UINT        cNames,    /* [in] Number of names in rgszNames */
  98         DISPID     *rgdispid)  /* [out] Destination for converted DISPIDs */
  99 {
 100     return ITypeInfo_GetIDsOfNames(ptinfo, rgszNames, cNames, rgdispid);
 101 }
 102
 103 /******************************************************************************
 104  *              DispGetParam (OLEAUT32.28)
 105  *
 106  * Retrieve a parameter from a DISPPARAMS structure and coerce it to the
 107  * specified variant type.
 108  *
 109  * NOTES
 110  *  Coercion is done using system (0) locale.
 111  *
 112  * RETURNS
 113  *  Success: S_OK.
 114  *  Failure: DISP_E_PARAMNOTFOUND, if position is invalid. or
 115  *           DISP_E_TYPEMISMATCH, if the coercion failed. puArgErr is
 116  *           set to the index of the argument in pdispparams.
 117  */
 118 HRESULT WINAPI DispGetParam(
 119         DISPPARAMS *pdispparams, /* [in] Parameter list */
 120         UINT        position,    /* [in] Position of parameter to coerce in pdispparams */
 121         VARTYPE     vtTarg,      /* [in] Type of value to coerce to */
 122         VARIANT    *pvarResult,  /* [out] Destination for resulting variant */
 123         UINT       *puArgErr)    /* [out] Destination for error code */
 124 {
 125     /* position is counted backwards */
 126     UINT pos;
 127     HRESULT hr;
 128
 129     TRACE("position=%d, cArgs=%d, cNamedArgs=%d\n",
 130           position, pdispparams->cArgs, pdispparams->cNamedArgs);
 131
 132     if (position < pdispparams->cArgs)
 133     {
 134       /* positional arg? */
 135       pos = pdispparams->cArgs - position - 1;
 136     }
 137     else
 138     {
 139       /* FIXME: is this how to handle named args? */
 140       for (pos=0; pos<pdispparams->cNamedArgs; pos++)
 141         if (pdispparams->rgdispidNamedArgs[pos] == position) break;
 142
 143       if (pos==pdispparams->cNamedArgs)
 144         return DISP_E_PARAMNOTFOUND;
 145     }
 146
 147     if (pdispparams->cArgs > 0 && !pdispparams->rgvarg)
 148     {
 149         hr = E_INVALIDARG;
 150         goto done;
 151     }
 152
 153     if (!pvarResult)
 154     {
 155         hr = E_INVALIDARG;
 156         goto done;
 157     }
 158
 159     hr = VariantChangeType(pvarResult,
 160                            &pdispparams->rgvarg[pos],
 161                            0, vtTarg);
 162
 163 done:
 164     if (FAILED(hr))
 165         *puArgErr = pos;
 166
 167     return hr;
 168 }
 169
 170
 171 /******************************************************************************
 172  * IDispatch {OLEAUT32}
 173  *
 174  * NOTES
 175  *  The IDispatch interface provides a single interface to dispatch method calls,
 176  *  regardless of whether the object to be called is in or out of process,
 177  *  local or remote (e.g. being called over a network). This interface is late-bound
 178  *  (linked at run-time), as opposed to early-bound (linked at compile time).
 179  *
 180  *  The interface is used by objects that wish to called by scripting
 181  *  languages such as VBA, in order to minimise the amount of COM and C/C++
 182  *  knowledge required, or by objects that wish to live out of process from code
 183  *  that will call their methods.
 184  *
 185  *  Method, property and parameter names can be localised. The details required to
 186  *  map names to methods and parameters are collected in a type library, usually
 187  *  output by an IDL compiler using the objects IDL description. This information is
 188  *  accessible programmatically through the ITypeLib interface (for a type library),
 189  *  and the ITypeInfo interface (for an object within the type library). Type information
 190  *  can also be created at run-time using CreateDispTypeInfo().
 191  *
 192  * WRAPPERS
 193  *  Instead of using IDispatch directly, there are several wrapper functions available
 194  *  to simplify the process of calling an objects methods through IDispatch.
 195  *
 196  *  A standard implementation of an IDispatch object is created by calling
 197  *  CreateStdDispatch(). Numeric Id values for the parameters and methods (DISPIDs)
 198  *  of an object of interest are retrieved by calling DispGetIDsOfNames(). DispGetParam()
 199  *  retrieves information about a particular parameter. Finally the DispInvoke()
 200  *  function is responsible for actually calling methods on an object.
 201  *
 202  * METHODS
 203  */
 204
 205 typedef struct
 206 {
 207     IDispatch IDispatch_iface;
 208     void * pvThis;
 209     ITypeInfo * pTypeInfo;
 210     LONG ref;
 211 } StdDispatch;
 212
 213 static inline StdDispatch *impl_from_IDispatch(IDispatch *iface)
 214 {
 215     return CONTAINING_RECORD(iface, StdDispatch, IDispatch_iface);
 216 }
 217
 218 /******************************************************************************
 219  * IDispatch_QueryInterface {OLEAUT32}
 220  *
 221  * See IUnknown_QueryInterface.
 222  */
 223 static HRESULT WINAPI StdDispatch_QueryInterface(
 224   LPDISPATCH iface,
 225   REFIID riid,
 226   void** ppvObject)
 227 {
 228     StdDispatch *This = impl_from_IDispatch(iface);
 229     TRACE("(%p)->(%s, %p)\n", This, debugstr_guid(riid), ppvObject);
 230
 231     *ppvObject = NULL;
 232
 233     if (IsEqualIID(riid, &IID_IDispatch) ||
 234         IsEqualIID(riid, &IID_IUnknown))
 235     {
 236         *ppvObject = iface;
 237         IDispatch_AddRef(iface);
 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 = impl_from_IDispatch(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 = impl_from_IDispatch(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     TRACE("(%p)\n", pctinfo);
 299     *pctinfo = 1;
 300     return S_OK;
 301 }
 302
 303 /******************************************************************************
 304  * IDispatch_GetTypeInfo {OLEAUT32}
 305  *
 306  * Get type information from an IDispatch interface.
 307  *
 308  * PARAMS
 309  *  iface   [I] IDispatch interface
 310  *  iTInfo  [I] Index of type information.
 311  *  lcid    [I] Locale of the type information to get
 312  *  ppTInfo [O] Destination for the ITypeInfo object
 313  *
 314  * RETURNS
 315  *  Success: S_OK. ppTInfo is updated with the objects type information
 316  *  Failure: DISP_E_BADINDEX, if iTInfo is any value other than 0.
 317  *
 318  * NOTES
 319  *  See IDispatch.
 320  */
 321 static HRESULT WINAPI StdDispatch_GetTypeInfo(LPDISPATCH iface, UINT iTInfo, LCID lcid, ITypeInfo** ppTInfo)
 322 {
 323     StdDispatch *This = impl_from_IDispatch(iface);
 324     TRACE("(%d, %x, %p)\n", iTInfo, lcid, ppTInfo);
 325
 326     *ppTInfo = NULL;
 327     if (iTInfo != 0)
 328         return DISP_E_BADINDEX;
 329
 330     *ppTInfo = This->pTypeInfo;
 331     ITypeInfo_AddRef(*ppTInfo);
 332
 333     return S_OK;
 334 }
 335
 336 /******************************************************************************
 337  * IDispatch_GetIDsOfNames {OLEAUT32}
 338  *
 339  * Convert a methods name and an optional set of parameter names into DISPIDs
 340  * for passing to IDispatch_Invoke().
 341  *
 342  * PARAMS
 343  *  iface     [I] IDispatch interface
 344  *  riid      [I] Reserved, set to IID_NULL
 345  *  rgszNames [I] Name to convert
 346  *  cNames    [I] Number of names in rgszNames
 347  *  lcid      [I] Locale of the type information to convert from
 348  *  rgDispId  [O] Destination for converted DISPIDs.
 349  *
 350  * RETURNS
 351  *  Success: S_OK.
 352  *  Failure: DISP_E_UNKNOWNNAME, if any of the names is invalid.
 353  *           DISP_E_UNKNOWNLCID if lcid is invalid.
 354  *           Otherwise, an HRESULT error code.
 355  *
 356  * NOTES
 357  *  This call defers to ITypeInfo_GetIDsOfNames(), using the ITypeInfo object
 358  *  contained within the IDispatch object.
 359  *  The first member of the names list must be a method name. The names following
 360  *  the method name are the parameters for that method.
 361  */
 362 static HRESULT WINAPI StdDispatch_GetIDsOfNames(LPDISPATCH iface, REFIID riid, LPOLESTR * rgszNames, UINT cNames, LCID lcid, DISPID * rgDispId)
 363 {
 364     StdDispatch *This = impl_from_IDispatch(iface);
 365     TRACE("(%s, %p, %d, 0x%x, %p)\n", debugstr_guid(riid), rgszNames, cNames, lcid, rgDispId);
 366
 367     if (!IsEqualGUID(riid, &IID_NULL))
 368     {
 369         FIXME(" expected riid == IID_NULL\n");
 370         return E_INVALIDARG;
 371     }
 372     return DispGetIDsOfNames(This->pTypeInfo, rgszNames, cNames, rgDispId);
 373 }
 374
 375 /******************************************************************************
 376  * IDispatch_Invoke {OLEAUT32}
 377  *
 378  * Call an object method.
 379  *
 380  * PARAMS
 381  *  iface        [I] IDispatch interface
 382  *  dispIdMember [I] DISPID of the method (from GetIDsOfNames())
 383  *  riid         [I] Reserved, set to IID_NULL
 384  *  lcid         [I] Locale of the type information to convert parameters with
 385  *  wFlags,      [I] Kind of method call (DISPATCH_ flags from "oaidl.h")
 386  *  pDispParams  [I] Array of method arguments
 387  *  pVarResult   [O] Destination for the result of the call
 388  *  pExcepInfo   [O] Destination for exception information
 389  *  puArgErr     [O] Destination for bad argument
 390  *
 391  * RETURNS
 392  *  Success: S_OK.
 393  *  Failure: See DispInvoke() for failure cases.
 394  *
 395  * NOTES
 396  *  See DispInvoke() and IDispatch().
 397  */
 398 static HRESULT WINAPI StdDispatch_Invoke(LPDISPATCH iface, DISPID dispIdMember, REFIID riid, LCID lcid,
 399                                          WORD wFlags, DISPPARAMS * pDispParams, VARIANT * pVarResult,
 400                                          EXCEPINFO * pExcepInfo, UINT * puArgErr)
 401 {
 402     StdDispatch *This = impl_from_IDispatch(iface);
 403     TRACE("(%d, %s, 0x%x, 0x%x, %p, %p, %p, %p)\n", dispIdMember, debugstr_guid(riid), lcid, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 404
 405     if (!IsEqualGUID(riid, &IID_NULL))
 406     {
 407         FIXME(" expected riid == IID_NULL\n");
 408         return E_INVALIDARG;
 409     }
 410     return DispInvoke(This->pvThis, This->pTypeInfo, dispIdMember, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 411 }
 412
 413 static const IDispatchVtbl StdDispatch_VTable =
 414 {
 415   StdDispatch_QueryInterface,
 416   StdDispatch_AddRef,
 417   StdDispatch_Release,
 418   StdDispatch_GetTypeInfoCount,
 419   StdDispatch_GetTypeInfo,
 420   StdDispatch_GetIDsOfNames,
 421   StdDispatch_Invoke
 422 };
 423
 424 /******************************************************************************
 425  * CreateStdDispatch [OLEAUT32.32]
 426  *
 427  * Create and return a standard IDispatch object.
 428  *
 429  * RETURNS
 430  *  Success: S_OK. ppunkStdDisp contains the new object.
 431  *  Failure: An HRESULT error code.
 432  *
 433  * NOTES
 434  *  Outer unknown appears to be completely ignored.
 435  */
 436 HRESULT WINAPI CreateStdDispatch(
 437         IUnknown* punkOuter,
 438         void* pvThis,
 439         ITypeInfo* ptinfo,
 440         IUnknown** stddisp)
 441 {
 442     StdDispatch *pStdDispatch;
 443
 444     TRACE("(%p, %p, %p, %p)\n", punkOuter, pvThis, ptinfo, stddisp);
 445
 446     if (!pvThis || !ptinfo || !stddisp)
 447         return E_INVALIDARG;
 448
 449     pStdDispatch = CoTaskMemAlloc(sizeof(StdDispatch));
 450     if (!pStdDispatch)
 451         return E_OUTOFMEMORY;
 452
 453     pStdDispatch->IDispatch_iface.lpVtbl = &StdDispatch_VTable;
 454     pStdDispatch->pvThis = pvThis;
 455     pStdDispatch->pTypeInfo = ptinfo;
 456     pStdDispatch->ref = 1;
 457
 458     /* we keep a reference to the type info so prevent it from
 459      * being destroyed until we are done with it */
 460     ITypeInfo_AddRef(ptinfo);
 461     *stddisp = (IUnknown*)&pStdDispatch->IDispatch_iface;
 462
 463     return S_OK;
 464 }