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 <stdlib.h>
  23 #include <string.h>
  24 #include <stdarg.h>
  25 #include <stdio.h>
  26 #include <ctype.h>
  27
  28 #define COBJMACROS
  29
  30 #include "windef.h"
  31 #include "winbase.h"
  32 #include "objbase.h"
  33 #include "oleauto.h"
  34 #include "winerror.h"
  35
  36 #include "wine/debug.h"
  37
  38 WINE_DEFAULT_DEBUG_CHANNEL(ole);
  39
  40 /******************************************************************************
  41  *              DispInvoke (OLEAUT32.30)
  42  *
  43  * Call an object method using the information from its type library.
  44  *
  45  * RETURNS
  46  *  Success: S_OK.
  47  *  Failure: Returns DISP_E_EXCEPTION and updates pexcepinfo if an exception occurs.
  48  *           DISP_E_BADPARAMCOUNT if the number of parameters is incorrect.
  49  *           DISP_E_MEMBERNOTFOUND if the method does not exist.
  50  *           puArgErr is updated if a parameter error (see notes) occurs.
  51  *           Otherwise, returns the result of calling ITypeInfo_Invoke().
  52  *
  53  * NOTES
  54  *  Parameter errors include the following:
  55  *| DISP_E_BADVARTYPE
  56  *| E_INVALIDARG            An argument was invalid
  57  *| DISP_E_TYPEMISMATCH,
  58  *| DISP_E_OVERFLOW         An argument was valid but could not be coerced
  59  *| DISP_E_PARAMNOTOPTIONAL A non optional parameter was not passed
  60  *| DISP_E_PARAMNOTFOUND    A parameter was passed that was not expected by the method
  61  *  This call defers to ITypeInfo_Invoke().
  62  */
  63 HRESULT WINAPI DispInvoke(
  64         VOID       *_this,        /* [in] Object to call method on */
  65         ITypeInfo  *ptinfo,       /* [in] Object type info */
  66         DISPID      dispidMember, /* [in] DISPID of the member (e.g. from GetIDsOfNames()) */
  67         USHORT      wFlags,       /* [in] Kind of method call (DISPATCH_ flags from "oaidl.h") */
  68         DISPPARAMS *pparams,      /* [in] Array of method arguments */
  69         VARIANT    *pvarResult,   /* [out] Destination for the result of the call */
  70         EXCEPINFO  *pexcepinfo,   /* [out] Destination for exception information */
  71         UINT       *puArgErr)     /* [out] Destination for bad argument */
  72 {
  73     TRACE("\n");
  74
  75     return ITypeInfo_Invoke(ptinfo, _this, dispidMember, wFlags,
  76                             pparams, pvarResult, pexcepinfo, puArgErr);
  77 }
  78
  79 /******************************************************************************
  80  *              DispGetIDsOfNames (OLEAUT32.29)
  81  *
  82  * Convert a set of parameter names to DISPIDs for DispInvoke().
  83  *
  84  * RETURNS
  85  *  Success: S_OK.
  86  *  Failure: An HRESULT error code.
  87  *
  88  * NOTES
  89  *  This call defers to ITypeInfo_GetIDsOfNames(). The ITypeInfo interface passed
  90  *  as ptinfo contains the information to map names to DISPIDs.
  91  */
  92 HRESULT WINAPI DispGetIDsOfNames(
  93         ITypeInfo  *ptinfo,    /* [in] Object's type info */
  94         OLECHAR   **rgszNames, /* [in] Array of names to get DISPIDs for */
  95         UINT        cNames,    /* [in] Number of names in rgszNames */
  96         DISPID     *rgdispid)  /* [out] Destination for converted DISPIDs */
  97 {
  98     return ITypeInfo_GetIDsOfNames(ptinfo, rgszNames, cNames, rgdispid);
  99 }
 100
 101 /******************************************************************************
 102  *              DispGetParam (OLEAUT32.28)
 103  *
 104  * Retrieve a parameter from a DISPPARAMS structure and coerce it to the
 105  * specified variant type.
 106  *
 107  * NOTES
 108  *  Coercion is done using system (0) locale.
 109  *
 110  * RETURNS
 111  *  Success: S_OK.
 112  *  Failure: DISP_E_PARAMNOTFOUND, if position is invalid. or
 113  *           DISP_E_TYPEMISMATCH, if the coercion failed. puArgErr is
 114  *           set to the index of the argument in pdispparams.
 115  */
 116 HRESULT WINAPI DispGetParam(
 117         DISPPARAMS *pdispparams, /* [in] Parameter list */
 118         UINT        position,    /* [in] Position of parameter to coerce in pdispparams */
 119         VARTYPE     vtTarg,      /* [in] Type of value to coerce to */
 120         VARIANT    *pvarResult,  /* [out] Destination for resulting variant */
 121         UINT       *puArgErr)    /* [out] Destination for error code */
 122 {
 123     /* position is counted backwards */
 124     UINT pos;
 125     HRESULT hr;
 126
 127     TRACE("position=%d, cArgs=%d, cNamedArgs=%d\n",
 128           position, pdispparams->cArgs, pdispparams->cNamedArgs);
 129
 130     if (position < pdispparams->cArgs)
 131     {
 132       /* positional arg? */
 133       pos = pdispparams->cArgs - position - 1;
 134     }
 135     else
 136     {
 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
 145     if (pdispparams->cArgs > 0 && !pdispparams->rgvarg)
 146     {
 147         hr = E_INVALIDARG;
 148         goto done;
 149     }
 150
 151     if (!pvarResult)
 152     {
 153         hr = E_INVALIDARG;
 154         goto done;
 155     }
 156
 157     hr = VariantChangeType(pvarResult,
 158                            &pdispparams->rgvarg[pos],
 159                            0, vtTarg);
 160
 161 done:
 162     if (FAILED(hr))
 163         *puArgErr = pos;
 164
 165     return hr;
 166 }
 167
 168
 169 /******************************************************************************
 170  * IDispatch {OLEAUT32}
 171  *
 172  * NOTES
 173  *  The IDispatch interface provides a single interface to dispatch method calls,
 174  *  regardless of whether the object to be called is in or out of process,
 175  *  local or remote (e.g. being called over a network). This interface is late-bound
 176  *  (linked at run-time), as opposed to early-bound (linked at compile time).
 177  *
 178  *  The interface is used by objects that wish to called by scripting
 179  *  languages such as VBA, in order to minimize the amount of COM and C/C++
 180  *  knowledge required, or by objects that wish to live out of process from code
 181  *  that will call their methods.
 182  *
 183  *  Method, property and parameter names can be localised. The details required to
 184  *  map names to methods and parameters are collected in a type library, usually
 185  *  output by an IDL compiler using the objects IDL description. This information is
 186  *  accessible programmatically through the ITypeLib interface (for a type library),
 187  *  and the ITypeInfo interface (for an object within the type library). Type information
 188  *  can also be created at run-time using CreateDispTypeInfo().
 189  *
 190  * WRAPPERS
 191  *  Instead of using IDispatch directly, there are several wrapper functions available
 192  *  to simplify the process of calling an objects methods through IDispatch.
 193  *
 194  *  A standard implementation of an IDispatch object is created by calling
 195  *  CreateStdDispatch(). Numeric Id values for the parameters and methods (DISPIDs)
 196  *  of an object of interest are retrieved by calling DispGetIDsOfNames(). DispGetParam()
 197  *  retrieves information about a particular parameter. Finally the DispInvoke()
 198  *  function is responsible for actually calling methods on an object.
 199  *
 200  * METHODS
 201  */
 202
 203 typedef struct
 204 {
 205     IDispatch IDispatch_iface;
 206     void * pvThis;
 207     ITypeInfo * pTypeInfo;
 208     LONG ref;
 209 } StdDispatch;
 210
 211 static inline StdDispatch *impl_from_IDispatch(IDispatch *iface)
 212 {
 213     return CONTAINING_RECORD(iface, StdDispatch, IDispatch_iface);
 214 }
 215
 216 /******************************************************************************
 217  * IDispatch_QueryInterface {OLEAUT32}
 218  *
 219  * See IUnknown_QueryInterface.
 220  */
 221 static HRESULT WINAPI StdDispatch_QueryInterface(
 222   LPDISPATCH iface,
 223   REFIID riid,
 224   void** ppvObject)
 225 {
 226     StdDispatch *This = impl_from_IDispatch(iface);
 227     TRACE("(%p)->(%s, %p)\n", This, debugstr_guid(riid), ppvObject);
 228
 229     *ppvObject = NULL;
 230
 231     if (IsEqualIID(riid, &IID_IDispatch) ||
 232         IsEqualIID(riid, &IID_IUnknown))
 233     {
 234         *ppvObject = iface;
 235         IDispatch_AddRef(iface);
 236         return S_OK;
 237     }
 238     return E_NOINTERFACE;
 239 }
 240
 241 /******************************************************************************
 242  * IDispatch_AddRef {OLEAUT32}
 243  *
 244  * See IUnknown_AddRef.
 245  */
 246 static ULONG WINAPI StdDispatch_AddRef(LPDISPATCH iface)
 247 {
 248     StdDispatch *This = impl_from_IDispatch(iface);
 249     ULONG refCount = InterlockedIncrement(&This->ref);
 250
 251     TRACE("(%p)->(ref before=%u)\n",This, refCount - 1);
 252
 253     return refCount;
 254 }
 255
 256 /******************************************************************************
 257  * IDispatch_Release {OLEAUT32}
 258  *
 259  * See IUnknown_Release.
 260  */
 261 static ULONG WINAPI StdDispatch_Release(LPDISPATCH iface)
 262 {
 263     StdDispatch *This = impl_from_IDispatch(iface);
 264     ULONG refCount = InterlockedDecrement(&This->ref);
 265
 266     TRACE("(%p)->(ref before=%u)\n", This, refCount + 1);
 267
 268     if (!refCount)
 269     {
 270         ITypeInfo_Release(This->pTypeInfo);
 271         CoTaskMemFree(This);
 272     }
 273
 274     return refCount;
 275 }
 276
 277 /******************************************************************************
 278  * IDispatch_GetTypeInfoCount {OLEAUT32}
 279  *
 280  * Get the count of type information in an IDispatch interface.
 281  *
 282  * PARAMS
 283  *  iface   [I] IDispatch interface
 284  *  pctinfo [O] Destination for the count
 285  *
 286  * RETURNS
 287  *  Success: S_OK. pctinfo is updated with the count. This is always 1 if
 288  *           the object provides type information, and 0 if it does not.
 289  *  Failure: E_NOTIMPL. The object does not provide type information.
 290  *
 291  * NOTES
 292  *  See IDispatch() and IDispatch_GetTypeInfo().
 293  */
 294 static HRESULT WINAPI StdDispatch_GetTypeInfoCount(LPDISPATCH iface, UINT * pctinfo)
 295 {
 296     TRACE("(%p)\n", pctinfo);
 297     *pctinfo = 1;
 298     return S_OK;
 299 }
 300
 301 /******************************************************************************
 302  * IDispatch_GetTypeInfo {OLEAUT32}
 303  *
 304  * Get type information from an IDispatch interface.
 305  *
 306  * PARAMS
 307  *  iface   [I] IDispatch interface
 308  *  iTInfo  [I] Index of type information.
 309  *  lcid    [I] Locale of the type information to get
 310  *  ppTInfo [O] Destination for the ITypeInfo object
 311  *
 312  * RETURNS
 313  *  Success: S_OK. ppTInfo is updated with the objects type information
 314  *  Failure: DISP_E_BADINDEX, if iTInfo is any value other than 0.
 315  *
 316  * NOTES
 317  *  See IDispatch.
 318  */
 319 static HRESULT WINAPI StdDispatch_GetTypeInfo(LPDISPATCH iface, UINT iTInfo, LCID lcid, ITypeInfo** ppTInfo)
 320 {
 321     StdDispatch *This = impl_from_IDispatch(iface);
 322     TRACE("(%d, %x, %p)\n", iTInfo, lcid, ppTInfo);
 323
 324     *ppTInfo = NULL;
 325     if (iTInfo != 0)
 326         return DISP_E_BADINDEX;
 327
 328     *ppTInfo = This->pTypeInfo;
 329     ITypeInfo_AddRef(*ppTInfo);
 330
 331     return S_OK;
 332 }
 333
 334 /******************************************************************************
 335  * IDispatch_GetIDsOfNames {OLEAUT32}
 336  *
 337  * Convert a methods name and an optional set of parameter names into DISPIDs
 338  * for passing to IDispatch_Invoke().
 339  *
 340  * PARAMS
 341  *  iface     [I] IDispatch interface
 342  *  riid      [I] Reserved, set to IID_NULL
 343  *  rgszNames [I] Name to convert
 344  *  cNames    [I] Number of names in rgszNames
 345  *  lcid      [I] Locale of the type information to convert from
 346  *  rgDispId  [O] Destination for converted DISPIDs.
 347  *
 348  * RETURNS
 349  *  Success: S_OK.
 350  *  Failure: DISP_E_UNKNOWNNAME, if any of the names is invalid.
 351  *           DISP_E_UNKNOWNLCID if lcid is invalid.
 352  *           Otherwise, an HRESULT error code.
 353  *
 354  * NOTES
 355  *  This call defers to ITypeInfo_GetIDsOfNames(), using the ITypeInfo object
 356  *  contained within the IDispatch object.
 357  *  The first member of the names list must be a method name. The names following
 358  *  the method name are the parameters for that method.
 359  */
 360 static HRESULT WINAPI StdDispatch_GetIDsOfNames(LPDISPATCH iface, REFIID riid, LPOLESTR * rgszNames, UINT cNames, LCID lcid, DISPID * rgDispId)
 361 {
 362     StdDispatch *This = impl_from_IDispatch(iface);
 363     TRACE("(%s, %p, %d, 0x%x, %p)\n", debugstr_guid(riid), rgszNames, cNames, lcid, rgDispId);
 364
 365     if (!IsEqualGUID(riid, &IID_NULL))
 366     {
 367         FIXME(" expected riid == IID_NULL\n");
 368         return E_INVALIDARG;
 369     }
 370     return DispGetIDsOfNames(This->pTypeInfo, rgszNames, cNames, rgDispId);
 371 }
 372
 373 /******************************************************************************
 374  * IDispatch_Invoke {OLEAUT32}
 375  *
 376  * Call an object method.
 377  *
 378  * PARAMS
 379  *  iface        [I] IDispatch interface
 380  *  dispIdMember [I] DISPID of the method (from GetIDsOfNames())
 381  *  riid         [I] Reserved, set to IID_NULL
 382  *  lcid         [I] Locale of the type information to convert parameters with
 383  *  wFlags,      [I] Kind of method call (DISPATCH_ flags from "oaidl.h")
 384  *  pDispParams  [I] Array of method arguments
 385  *  pVarResult   [O] Destination for the result of the call
 386  *  pExcepInfo   [O] Destination for exception information
 387  *  puArgErr     [O] Destination for bad argument
 388  *
 389  * RETURNS
 390  *  Success: S_OK.
 391  *  Failure: See DispInvoke() for failure cases.
 392  *
 393  * NOTES
 394  *  See DispInvoke() and IDispatch().
 395  */
 396 static HRESULT WINAPI StdDispatch_Invoke(LPDISPATCH iface, DISPID dispIdMember, REFIID riid, LCID lcid,
 397                                          WORD wFlags, DISPPARAMS * pDispParams, VARIANT * pVarResult,
 398                                          EXCEPINFO * pExcepInfo, UINT * puArgErr)
 399 {
 400     StdDispatch *This = impl_from_IDispatch(iface);
 401     TRACE("(%d, %s, 0x%x, 0x%x, %p, %p, %p, %p)\n", dispIdMember, debugstr_guid(riid), lcid, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 402
 403     if (!IsEqualGUID(riid, &IID_NULL))
 404     {
 405         FIXME(" expected riid == IID_NULL\n");
 406         return E_INVALIDARG;
 407     }
 408     return DispInvoke(This->pvThis, This->pTypeInfo, dispIdMember, wFlags, pDispParams, pVarResult, pExcepInfo, puArgErr);
 409 }
 410
 411 static const IDispatchVtbl StdDispatch_VTable =
 412 {
 413   StdDispatch_QueryInterface,
 414   StdDispatch_AddRef,
 415   StdDispatch_Release,
 416   StdDispatch_GetTypeInfoCount,
 417   StdDispatch_GetTypeInfo,
 418   StdDispatch_GetIDsOfNames,
 419   StdDispatch_Invoke
 420 };
 421
 422 /******************************************************************************
 423  * CreateStdDispatch [OLEAUT32.32]
 424  *
 425  * Create and return a standard IDispatch object.
 426  *
 427  * RETURNS
 428  *  Success: S_OK. ppunkStdDisp contains the new object.
 429  *  Failure: An HRESULT error code.
 430  *
 431  * NOTES
 432  *  Outer unknown appears to be completely ignored.
 433  */
 434 HRESULT WINAPI CreateStdDispatch(
 435         IUnknown* punkOuter,
 436         void* pvThis,
 437         ITypeInfo* ptinfo,
 438         IUnknown** stddisp)
 439 {
 440     StdDispatch *pStdDispatch;
 441
 442     TRACE("(%p, %p, %p, %p)\n", punkOuter, pvThis, ptinfo, stddisp);
 443
 444     if (!pvThis || !ptinfo || !stddisp)
 445         return E_INVALIDARG;
 446
 447     pStdDispatch = CoTaskMemAlloc(sizeof(StdDispatch));
 448     if (!pStdDispatch)
 449         return E_OUTOFMEMORY;
 450
 451     pStdDispatch->IDispatch_iface.lpVtbl = &StdDispatch_VTable;
 452     pStdDispatch->pvThis = pvThis;
 453     pStdDispatch->pTypeInfo = ptinfo;
 454     pStdDispatch->ref = 1;
 455
 456     /* we keep a reference to the type info so prevent it from
 457      * being destroyed until we are done with it */
 458     ITypeInfo_AddRef(ptinfo);
 459     *stddisp = (IUnknown*)&pStdDispatch->IDispatch_iface;
 460
 461     return S_OK;
 462 }