wnet.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

                    else if (lpNet->lpRemoteName)
                    {
                        *lphEnum = (HANDLE)_createGlobalEnumeratorW(dwScope,
                         dwType, dwUsage, lpNet);
                        ret = *lphEnum ? WN_SUCCESS : WN_OUT_OF_MEMORY;
                    }
                    else
                    {
                        if (lpNet->lpComment && !strcmpW(lpNet->lpComment,
                         providerTable->entireNetwork))
                        {
                            /* comment matches the "Entire Network", enumerate
                             * global scope of every provider
                             */
                            *lphEnum = (HANDLE)_createGlobalEnumeratorW(dwScope,
                             dwType, dwUsage, lpNet);
                        }
                        else
                        {
                            /* this is the same as not having passed lpNet */
                            *lphEnum = (HANDLE)_createGlobalEnumeratorW(dwScope,
                             dwType, dwUsage, NULL);
                        }
                        ret = *lphEnum ? WN_SUCCESS : WN_OUT_OF_MEMORY;
                    }
                }
                else
                {
                    *lphEnum = (HANDLE)_createGlobalEnumeratorW(dwScope, dwType,
                     dwUsage, lpNet);
                    ret = *lphEnum ? WN_SUCCESS : WN_OUT_OF_MEMORY;
                }
                break;
            case RESOURCE_CONTEXT:
                *lphEnum = (HANDLE)_createContextEnumerator(dwScope, dwType,
                 dwUsage);
                ret = *lphEnum ? WN_SUCCESS : WN_OUT_OF_MEMORY;
                break;
            case RESOURCE_REMEMBERED:
            case RESOURCE_CONNECTED:
                *lphEnum = (HANDLE)_createNullEnumerator();
                ret = *lphEnum ? WN_SUCCESS : WN_OUT_OF_MEMORY;
                break;
            default:
                WARN("unknown scope 0x%08x\n", dwScope);
                ret = WN_BAD_VALUE;
        }
    }
    if (ret)
        SetLastError(ret);
    TRACE("Returning %d\n", ret);
    return ret;
}

/*********************************************************************
 * WNetEnumResourceA [MPR.@]
 */
DWORD WINAPI WNetEnumResourceA( HANDLE hEnum, LPDWORD lpcCount,
                                LPVOID lpBuffer, LPDWORD lpBufferSize )
{
    DWORD ret;

    TRACE( "(%p, %p, %p, %p)\n", hEnum, lpcCount, lpBuffer, lpBufferSize );

    if (!hEnum)
        ret = WN_BAD_POINTER;
    else if (!lpcCount)
        ret = WN_BAD_POINTER;
    else if (!lpBuffer)
        ret = WN_BAD_POINTER;
    else if (!lpBufferSize)
        ret = WN_BAD_POINTER;
    else if (*lpBufferSize < sizeof(NETRESOURCEA))
    {
        *lpBufferSize = sizeof(NETRESOURCEA);
        ret = WN_MORE_DATA;
    }
    else
    {
        DWORD localCount = *lpcCount, localSize = *lpBufferSize;
        LPVOID localBuffer = HeapAlloc(GetProcessHeap(), 0, localSize);

        if (localBuffer)
        {
            ret = WNetEnumResourceW(hEnum, &localCount, localBuffer,
             &localSize);
            if (ret == WN_SUCCESS || (ret == WN_MORE_DATA && localCount != -1))
            {
                /* FIXME: this isn't necessarily going to work in the case of
                 * WN_MORE_DATA, because our enumerator may have moved on to
                 * the next provider.  MSDN states that a large (16KB) buffer
                 * size is the appropriate usage of this function, so
                 * hopefully it won't be an issue.
                 */
                ret = _thunkNetResourceArrayWToA((LPNETRESOURCEW)localBuffer,
                 &localCount, lpBuffer, lpBufferSize);
                *lpcCount = localCount;
            }
            HeapFree(GetProcessHeap(), 0, localBuffer);
        }
        else
            ret = WN_OUT_OF_MEMORY;
    }
    if (ret)
        SetLastError(ret);
    TRACE("Returning %d\n", ret);
    return ret;
}

static DWORD _countProviderBytesW(PWNetProvider provider)
{
    DWORD ret;

    if (provider)
    {
        ret = sizeof(NETRESOURCEW);
        ret += 2 * (strlenW(provider->name) + 1) * sizeof(WCHAR);
    }
    else
        ret = 0;
    return ret;
}

static DWORD _enumerateProvidersW(PWNetEnumerator enumerator, LPDWORD lpcCount,
 LPVOID lpBuffer, const DWORD *lpBufferSize)
{
    DWORD ret;

    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_GLOBAL)
        return WN_BAD_VALUE;
    if (!lpcCount)
        return WN_BAD_POINTER;
    if (!lpBuffer)
        return WN_BAD_POINTER;
    if (!lpBufferSize)
        return WN_BAD_POINTER;
    if (*lpBufferSize < sizeof(NETRESOURCEA))
        return WN_MORE_DATA;

    if (!providerTable || enumerator->providerIndex >= 
     providerTable->numProviders)
        ret = WN_NO_MORE_ENTRIES;
    else
    {
        DWORD bytes = 0, count = 0, countLimit, i;
        LPNETRESOURCEW resource;
        LPWSTR strNext;

        countLimit = *lpcCount == -1 ?
         providerTable->numProviders - enumerator->providerIndex : *lpcCount;
        while (count < countLimit && bytes < *lpBufferSize)
        {
            DWORD bytesNext = _countProviderBytesW(
             &providerTable->table[count + enumerator->providerIndex]);

            if (bytes + bytesNext < *lpBufferSize)
            {
                bytes += bytesNext;
                count++;
            }
        }
        strNext = (LPWSTR)((LPBYTE)lpBuffer + count * sizeof(NETRESOURCEW));
        for (i = 0, resource = (LPNETRESOURCEW)lpBuffer; i < count;
         i++, resource++)
        {
            resource->dwScope = RESOURCE_GLOBALNET;
            resource->dwType = RESOURCETYPE_ANY;
            resource->dwDisplayType = RESOURCEDISPLAYTYPE_NETWORK;
            resource->dwUsage = RESOURCEUSAGE_CONTAINER |
             RESOURCEUSAGE_RESERVED;
            resource->lpLocalName = NULL;
            resource->lpRemoteName = strNext;
            strcpyW(resource->lpRemoteName,
             providerTable->table[i + enumerator->providerIndex].name);
            strNext += strlenW(resource->lpRemoteName) + 1;
            resource->lpComment = NULL;
            resource->lpProvider = strNext;
            strcpyW(resource->lpProvider,
             providerTable->table[i + enumerator->providerIndex].name);
            strNext += strlenW(resource->lpProvider) + 1;
        }
        enumerator->providerIndex += count;
        *lpcCount = count;
        ret = count > 0 ? WN_SUCCESS : WN_MORE_DATA;
    }
    TRACE("Returning %d\n", ret);
    return ret;
}

/* Advances the enumerator (assumed to be a global enumerator) to the next
 * provider that supports the enumeration scope passed to WNetOpenEnum.  Does
 * not open a handle with the next provider.
 * If the existing handle is NULL, may leave the enumerator unchanged, since
 * the current provider may support the desired scope.
 * If the existing handle is not NULL, closes it before moving on.
 * Returns WN_SUCCESS on success, WN_NO_MORE_ENTRIES if there is no available
 * provider, and another error on failure.
 */
static DWORD _globalEnumeratorAdvance(PWNetEnumerator enumerator)
{
    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_GLOBAL)
        return WN_BAD_VALUE;
    if (!providerTable || enumerator->providerIndex >=
     providerTable->numProviders)
        return WN_NO_MORE_ENTRIES;

    if (enumerator->providerDone)
    {
        enumerator->providerDone = FALSE;
        if (enumerator->handle)
        {
            providerTable->table[enumerator->providerIndex].closeEnum(
             enumerator->handle);
            enumerator->handle = NULL;
            enumerator->providerIndex++;
        }
        for (; enumerator->providerIndex < providerTable->numProviders &&
         !(enumerator->dwScope & providerTable->table
         [enumerator->providerIndex].dwEnumScopes);
         enumerator->providerIndex++)
            ;
    }
    return enumerator->providerIndex < providerTable->numProviders ?
     WN_SUCCESS : WN_NO_MORE_ENTRIES;
}

/* "Passes through" call to the next provider that supports the enumeration
 * type.
 * FIXME: if one call to a provider's enumerator succeeds while there's still
 * space in lpBuffer, I don't call to the next provider.  The caller may not
 * expect that it should call EnumResourceW again with a return value of
 * WN_SUCCESS (depending what *lpcCount was to begin with).  That means strings
 * may have to be moved around a bit, ick.
 */
static DWORD _enumerateGlobalPassthroughW(PWNetEnumerator enumerator,
 LPDWORD lpcCount, LPVOID lpBuffer, LPDWORD lpBufferSize)
{
    DWORD ret;

    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_GLOBAL)
        return WN_BAD_VALUE;
    if (!lpcCount)
        return WN_BAD_POINTER;
    if (!lpBuffer)
        return WN_BAD_POINTER;
    if (!lpBufferSize)
        return WN_BAD_POINTER;
    if (*lpBufferSize < sizeof(NETRESOURCEW))
        return WN_MORE_DATA;

    ret = _globalEnumeratorAdvance(enumerator);
    if (ret == WN_SUCCESS)
    {
        ret = providerTable->table[enumerator->providerIndex].
         openEnum(enumerator->dwScope, enumerator->dwType,
         enumerator->dwUsage, enumerator->lpNet,
         &enumerator->handle);
        if (ret == WN_SUCCESS)
        {
            ret = providerTable->table[enumerator->providerIndex].
             enumResource(enumerator->handle, lpcCount, lpBuffer,
             lpBufferSize);
            if (ret != WN_MORE_DATA)
                enumerator->providerDone = TRUE;
        }
    }
    TRACE("Returning %d\n", ret);
    return ret;
}

static DWORD _enumerateGlobalW(PWNetEnumerator enumerator, LPDWORD lpcCount,
 LPVOID lpBuffer, LPDWORD lpBufferSize)
{
    DWORD ret;

    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_GLOBAL)
        return WN_BAD_VALUE;
    if (!lpcCount)
        return WN_BAD_POINTER;
    if (!lpBuffer)
        return WN_BAD_POINTER;
    if (!lpBufferSize)
        return WN_BAD_POINTER;
    if (*lpBufferSize < sizeof(NETRESOURCEW))
        return WN_MORE_DATA;
    if (!providerTable)
        return WN_NO_NETWORK;

    switch (enumerator->dwScope)
    {
        case RESOURCE_GLOBALNET:
            if (enumerator->lpNet)
                ret = _enumerateGlobalPassthroughW(enumerator, lpcCount,
                 lpBuffer, lpBufferSize);
            else
                ret = _enumerateProvidersW(enumerator, lpcCount, lpBuffer,
                 lpBufferSize);
            break;
        case RESOURCE_CONTEXT:
            ret = _enumerateGlobalPassthroughW(enumerator, lpcCount, lpBuffer,
             lpBufferSize);
            break;
        default:
            WARN("unexpected scope 0x%08x\n", enumerator->dwScope);
            ret = WN_NO_MORE_ENTRIES;
    }
    TRACE("Returning %d\n", ret);
    return ret;
}

static DWORD _enumerateProviderW(PWNetEnumerator enumerator, LPDWORD lpcCount,
 LPVOID lpBuffer, LPDWORD lpBufferSize)
{
    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_PROVIDER)
        return WN_BAD_VALUE;
    if (!enumerator->handle)
        return WN_BAD_VALUE;
    if (!lpcCount)
        return WN_BAD_POINTER;
    if (!lpBuffer)
        return WN_BAD_POINTER;
    if (!lpBufferSize)
        return WN_BAD_POINTER;
    if (!providerTable)
        return WN_NO_NETWORK;
    if (enumerator->providerIndex >= providerTable->numProviders)
        return WN_NO_MORE_ENTRIES;
    if (!providerTable->table[enumerator->providerIndex].enumResource)
        return WN_BAD_VALUE;
    return providerTable->table[enumerator->providerIndex].enumResource(
     enumerator->handle, lpcCount, lpBuffer, lpBufferSize);
}

static DWORD _enumerateContextW(PWNetEnumerator enumerator, LPDWORD lpcCount,
 LPVOID lpBuffer, LPDWORD lpBufferSize)
{
    DWORD ret;
    size_t cchEntireNetworkLen, bytesNeeded;

    if (!enumerator)
        return WN_BAD_POINTER;
    if (enumerator->enumType != WNET_ENUMERATOR_TYPE_CONTEXT)
        return WN_BAD_VALUE;
    if (!lpcCount)
        return WN_BAD_POINTER;
    if (!lpBuffer)
        return WN_BAD_POINTER;
    if (!lpBufferSize)
        return WN_BAD_POINTER;
    if (!providerTable)
        return WN_NO_NETWORK;

    cchEntireNetworkLen = strlenW(providerTable->entireNetwork) + 1;
    bytesNeeded = sizeof(NETRESOURCEW) + cchEntireNetworkLen * sizeof(WCHAR);
    if (*lpBufferSize < bytesNeeded)
    {
        *lpBufferSize = bytesNeeded;
        ret = WN_MORE_DATA;
    }
    else
    {
        LPNETRESOURCEW lpNet = (LPNETRESOURCEW)lpBuffer;

        lpNet->dwScope = RESOURCE_GLOBALNET;
        lpNet->dwType = enumerator->dwType;
        lpNet->dwDisplayType = RESOURCEDISPLAYTYPE_ROOT;
        lpNet->dwUsage = RESOURCEUSAGE_CONTAINER;