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ntel Corporation Proprietary Information
Copyright (c) 1995 Intel Corporation
This listing is supplied under the terms of a license agreement with
Intel Corporation and may not be used, copied, nor disclosed except in
accordance with the terms of that agreeement.
Module Name:
select.c
Abstract:
This module contains the “select“ entry points from the winsock
API. The following functions aare contained in this module.
select()
WSAEventSelect()
WSAAsyncSelect()
__WSAFDIsSet()
Author:
Dirk Brandewie dirk@mink.intel.com 14-06-1995
Revision History:
22-Aug-1995 dirk@mink.intel.com
Cleanup after code review. Moved includes to precomp.h
16-Aug-1995 dirk@mink.intel.com
Added implementation of __WSAFDIsSet
--*/
#include “precomp.h“
int WSAAPI
select (
IN int nfds,
IN OUT fd_set FAR *readfds,
IN OUT fd_set FAR *writefds,
IN OUT fd_set FAR *exceptfds,
IN const struct timeval FAR *timeout
)
/*++
Routine Description:
Determine the status of one or more sockets, waiting if necessary.
Arguments:
nfds - This argument is ignored and included only for the sake of
compatibility.
readfds - An optional pointer to a set of sockets to be checked
for readability.
writefds - An optional pointer to a set of sockets to be checked
for writability.
exceptfds - An optional pointer to a set of sockets to be checked
for errors.
timeout - The maximum time for select() to wait, or NULL for
blocking operation.
Returns:
select() returns the total number of descriptors which are ready
and contained in the fd_set structures, 0 if the time limit
expired, or SOCKET_ERROR if an error occurred. If the return
value is SOCKET_ERROR, The error code is stored with
SetLastError().
--*/
{
INT ReturnValue;
INT ErrorCode;
PDPROVIDER Provider;
PDSOCKET Socket;
SOCKET SocketID;
BOOL FoundSocket=FALSE;
ErrorCode = TURBO_PROLOG();
if (ErrorCode == ERROR_SUCCESS) {
__try {
// Look for a socket in the three fd_sets handed in. The first
// socket found will be used to select the service provider to
// service this call
if (readfds && readfds->fd_count)
{
SocketID = readfds->fd_array[0];
FoundSocket = TRUE;
} //if
if (!FoundSocket && writefds && writefds->fd_count )
{
SocketID = writefds->fd_array[0];
FoundSocket = TRUE;
} //if
if (!FoundSocket && exceptfds && exceptfds->fd_count )
{
SocketID = exceptfds->fd_array[0];
FoundSocket = TRUE;
} //if
}
__except (WS2_EXCEPTION_FILTER()) {
ErrorCode = WSAEFAULT;
goto ReturnError;
}
if (FoundSocket) {
Socket = DSOCKET::GetCountedDSocketFromSocket(SocketID);
if(Socket != NULL){
Provider = Socket->GetDProvider();
ReturnValue = Provider->WSPSelect(
nfds,
readfds,
writefds,
exceptfds,
timeout,
&ErrorCode);
Socket->DropDSocketReference();
if (ReturnValue!=SOCKET_ERROR)
return ReturnValue;
assert (ErrorCode!=NO_ERROR);
if (ErrorCode==NO_ERROR)
ErrorCode = WSASYSCALLFAILURE;
} //if
else {
ErrorCode = WSAENOTSOCK;
}
} //if
else {
ErrorCode = WSAEINVAL;
} //else
}
ReturnError:
SetLastError(ErrorCode);
return(SOCKET_ERROR);
} //select
int WSAAPI
WSAEventSelect(
IN SOCKET s,
IN WSAEVENT hEventObject,
IN long lNetworkEvents
)
/*++
Routine Description:
Specify an event object to be associated with the supplied set of
FD_XXX network events.
Arguments:
s - A descriptor identifying the socket.
hEventObject - A handle identifying the event object to be
associated with the supplied set of FD_XXX network
events.
lNetworkEvents - A bitmask which specifies the combination of
FD_XXX network events in which the application
has interest.
Returns:
Zero on success else SOCKET_Error. The error code is stored with
SetLastError().
--*/
{
INT ReturnValue;
INT ErrorCode;
PDPROVIDER Provider;
PDSOCKET Socket;
ErrorCode = TURBO_PROLOG();
if (ErrorCode == ERROR_SUCCESS) {
Socket = DSOCKET::GetCountedDSocketFromSocket(s);
if(Socket != NULL){
Provider = Socket->GetDProvider();
ReturnValue = Provider->WSPEventSelect(
s,
hEventObject,
lNetworkEvents,
&ErrorCode);
Socket->DropDSocketReference();
if (ReturnValue==ERROR_SUCCESS)
return ReturnValue;
assert (ErrorCode!=NO_ERROR);
if (ErrorCode==NO_ERROR)
ErrorCode = WSASYSCALLFAILURE;
}
else {
ErrorCode = WSAENOTSOCK;
}
}
SetLastError(ErrorCode);
return SOCKET_ERROR;
} //WSAEventSelect
int WSAAPI
WSAAsyncSelect(
IN SOCKET s,
IN HWND hWnd,
IN u_int wMsg,
IN long lEvent
)
/*++
Routine Description:
Request event notification for a socket.
Arguments:
s - A descriptor identifying the socket for which event notification is
required.
hWnd - A handle identifying the window which should receive a message when
a network event occurs.
wMsg - The message to be received when a network event occurs.
lEvent - A bitmask which specifies a combination of network events in which
the application is interested.
Returns:
The return value is 0 if the application‘s declaration of interest in the
network event set was successful. Otherwise the value SOCKET_ERROR is
returned, and a specific error number may be retrieved by calling
WSAGetLastError().
--*/
{
INT ReturnValue;
INT ErrorCode;
PDPROVIDER Provider;
PDSOCKET Socket;
ErrorCode = TURBO_PROLOG();
if (ErrorCode == ERROR_SUCCESS) {
Socket = DSOCKET::GetCountedDSocketFromSocket(s);
if(Socket != NULL){
Provider = Socket->GetDProvider();
ReturnValue = Provider->WSPAsyncSelect(
s,
hWnd,
wMsg,
lEvent,
&ErrorCode);
Socket->DropDSocketReference();
if (ReturnValue==ERROR_SUCCESS)
return ReturnValue;
assert (ErrorCode!=NO_ERROR);
if (ErrorCode==NO_ERROR)
ErrorCode = WSASYSCALLFAILURE;
}
else {
ErrorCode = WSAENOTSOCK;
}
}
SetLastError(ErrorCode);
return SOCKET_ERROR;
} //WSAAsyncSelect
int FAR PASCAL
__WSAFDIsSet(
SOCKET fd,
fd_set FAR *set)
/*++
Routine Description:
Determines if a specific socket is a contained in an FD_SET.
Arguments:
s - A descriptor identifying the socket.
set - A pointer to an FD_SET.
Returns:
Returns TRUE if socket s is a member of set, otherwise FALSE.
--*/
{
int i = set->fd_count; // index into FD_SET
int rc=FALSE; // user return code
while (i--){
if (set->fd_array[i] == fd) {
rc = TRUE;
} //if
} //while
return (rc);
} // __WSAFDIsSet
int FAR PASCAL
WPUFDIsSet(
SOCKET fd,
fd_set FAR *set)
/*++
Routine Description:
Determines if a specific socket is a contained in an FD_SET.
Arguments:
s - A descriptor identifying the socket.
set - A pointer to an FD_SET.
Returns:
Returns TRUE if socket s is a member of set, otherwise FALSE.
--*/
{
int return_value;
return_value = __WSAFDIsSet(
fd,
set
);
return(return_value);
} // WPUFDIsSet
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