w32sock.cpp

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//
// Local windows sockets
//

int local_win_socket::read(void* buf, size_t min_size, size_t max_size, 
			   time_t timeout)
{
    time_t start = 0;
    char* dst = (char*)buf;
    size_t size = 0;
    Error = ok;
    if (timeout != WAIT_FOREVER) { 
	start = time(NULL); 
	timeout *= 1000; // convert seconds to miliseconds
    }
    while (size < min_size && state == ss_open) {	
        RcvBuf->RcvWaitFlag = true;
	serialize();
	size_t begin = RcvBuf->DataBeg;
	size_t end = RcvBuf->DataEnd;
	size_t rcv_size = (begin <= end)
	    ? end - begin : sizeof(RcvBuf->Data) - begin;
	if (rcv_size > 0) { 
	    RcvBuf->RcvWaitFlag = false;
            if (rcv_size >= max_size) { 
	        memcpy(dst, &RcvBuf->Data[begin], max_size);
		begin += max_size;
		size += max_size;
	    } else { 
	        memcpy(dst, &RcvBuf->Data[begin], rcv_size);
		begin += rcv_size;
		dst += rcv_size;
		size += rcv_size;
		max_size -= rcv_size;
	    } 
	    RcvBuf->DataBeg = (begin == sizeof(RcvBuf->Data)) ? 0 : begin;
	    if (RcvBuf->SndWaitFlag) { 
		SetEvent(Signal[RTR]);
    	    }		
	} else {
	    HANDLE h[2];
	    h[0] = Signal[RD];
	    h[1] = Mutex;
	    int rc = WaitForMultipleObjects(2, h, false, timeout);
	    RcvBuf->RcvWaitFlag = false;
	    if (rc != WAIT_OBJECT_0) {
		if (rc == WAIT_OBJECT_0+1 || rc == WAIT_ABANDONED+1) { 
		    Error = broken_pipe;
		    ReleaseMutex(Mutex);
		} else if (rc == WAIT_TIMEOUT) { 
		    return size;
		} else { 
		    Error = GetLastError();
		}
		return -1;
	    }
	    if (timeout != WAIT_FOREVER) { 
		time_t now = time(NULL);
		timeout = timeout >= (now - start)*1000 
		    ? timeout - (now - start)*1000 : 0;  
	    }
	}
    }			
    return size < min_size ? -1 : (int)size;
}


bool local_win_socket::write(const void* buf, size_t size)
{
    char* src = (char*)buf;
    Error = ok;
    while (size > 0 && state == ss_open) {	
        SndBuf->SndWaitFlag = true;
	serialize();
	size_t begin = SndBuf->DataBeg;
	size_t end = SndBuf->DataEnd;
	size_t snd_size = (begin <= end) 
	    ? sizeof(SndBuf->Data) - end - (begin == 0)
	    : begin - end - 1;
	if (snd_size > 0) { 
	    SndBuf->SndWaitFlag = false;
            if (snd_size >= size) { 
	        memcpy(&SndBuf->Data[end], src, size);
		end += size;
	        size = 0;
	    } else { 
	        memcpy(&SndBuf->Data[end], src, snd_size);
		end += snd_size;
		src += snd_size;
		size -= snd_size;
	    } 
	    SndBuf->DataEnd = (end == sizeof(SndBuf->Data)) ? 0 : end;
	    if (SndBuf->RcvWaitFlag) { 
		SetEvent(Signal[TD]);
    	    }		
	} else {
	    HANDLE h[2];
	    h[0] = Signal[RTT];
	    h[1] = Mutex;
	    int rc = WaitForMultipleObjects(2, h, false, INFINITE);
	    RcvBuf->SndWaitFlag = false;
	    if (rc != WAIT_OBJECT_0) {
		if (rc == WAIT_OBJECT_0+1 || rc == WAIT_ABANDONED+1) { 
		    Error = broken_pipe;
		    ReleaseMutex(Mutex);
		} else { 
		    Error = GetLastError();
		}	
		return false;
	    }
	}
    }				
    return size == 0;
}

#define MAX_ADDRESS_LEN 64

local_win_socket::local_win_socket(const char* address)
{
    Name = new char[strlen(address)+1];
    strcpy(Name, address);
    Error = not_opened;
    Mutex = NULL;
}
 
bool local_win_socket::open(int)
{
    char buf[MAX_ADDRESS_LEN];	
    int  i;

    for (i = RD; i <= RTT; i++) {  
        sprintf(buf, "%s.%c", Name, i + '0');
	Signal[i] = CreateEvent(FASTDB_SECURITY_ATTRIBUTES, false, false, buf);
	if (GetLastError() == ERROR_ALREADY_EXISTS) { 
	    WaitForSingleObject(Signal[i], 0);
	}
	if (!Signal[i]) {
	    Error = GetLastError();
	    while (--i >= 0) { 
		CloseHandle(Signal[i]);
            }
	    return false;
        }	
    }
    sprintf(buf, "%s.shr", Name);
    BufHnd = CreateFileMapping(INVALID_HANDLE_VALUE, FASTDB_SECURITY_ATTRIBUTES, PAGE_READWRITE,
                               0, sizeof(socket_buf)*2, buf);
    if (!BufHnd) {
	Error = GetLastError();
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	return false;
    }
    RcvBuf = (socket_buf*)MapViewOfFile(BufHnd, FILE_MAP_ALL_ACCESS, 0, 0, 0);
    if (!RcvBuf) {
	Error = GetLastError();
	CloseHandle(BufHnd);
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	return false;
    }	
    SndBuf = RcvBuf+1;
    RcvBuf->DataBeg = RcvBuf->DataEnd = 0;
    SndBuf->DataBeg = SndBuf->DataEnd = 0;	 
    Error = ok;
    state = ss_open;
    return true;
}

local_win_socket::local_win_socket()
{
    int i;
    BufHnd = NULL;
    Mutex = NULL; 
    Name = NULL;

    for (i = RD; i <= RTT; i++) {  
	Signal[i] = CreateEvent(FASTDB_SECURITY_ATTRIBUTES, false, false, NULL);
	if (!Signal[i]) {
	    Error = GetLastError();
	    while (--i >= 0) { 
		CloseHandle(Signal[i]);
            }
	    return;
        }	
    }
    // create anonymous shared memory section
    BufHnd = CreateFileMapping(INVALID_HANDLE_VALUE, FASTDB_SECURITY_ATTRIBUTES, PAGE_READWRITE,
                               0, sizeof(socket_buf)*2, NULL);
    if (!BufHnd) {
	Error = GetLastError();
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	return;
    }
    RcvBuf = (socket_buf*)MapViewOfFile(BufHnd, FILE_MAP_ALL_ACCESS, 0, 0, 0);
    if (!RcvBuf) {
	Error = GetLastError();
	CloseHandle(BufHnd);
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	BufHnd = NULL;
	return;
    }	
    SndBuf = RcvBuf+1;
    RcvBuf->DataBeg = RcvBuf->DataEnd = 0;
    SndBuf->DataBeg = SndBuf->DataEnd = 0;	 
    Error = ok;
    state = ss_open;
}

local_win_socket::~local_win_socket()
{
    close();
    delete[] Name;
}	

socket_t* local_win_socket::accept()
{   
    HANDLE h[2];

    if (state != ss_open) {	
	return NULL;
    }
		    
    connect_data* cdp = (connect_data*)SndBuf->Data;
    cdp->Pid = GetCurrentProcessId();
    cdp->Mutex = WatchDogMutex;
    while (true) { 
	SetEvent(Signal[RTR]);
	int rc = WaitForSingleObject(Signal[RD], ACCEPT_TIMEOUT);
	if (rc == WAIT_OBJECT_0) {
	    if (state != ss_open) { 
		Error = not_opened;
		return NULL;
	    }
	    Error = ok;
	    break;
	} else if (rc != WAIT_TIMEOUT) { 
	    Error = GetLastError();
	    return NULL;
	}
    }
    local_win_socket* sock = new local_win_socket();
    sock->Mutex = ((connect_data*)RcvBuf->Data)->Mutex;
    accept_data* adp = (accept_data*)SndBuf->Data;
    adp->BufHnd = sock->BufHnd;
    for (int i = RD; i <= RTT; i++) { 
	adp->Signal[(i + TD - RD) & RTT] = sock->Signal[i]; 
    }
    SetEvent(Signal[TD]);
    h[0] = Signal[RD];
    h[1] = sock->Mutex;
    int rc = WaitForMultipleObjects(2, h, false, INFINITE);
    if (rc != WAIT_OBJECT_0) {
	if (rc == WAIT_OBJECT_0+1 || rc == WAIT_ABANDONED+1) { 
	    Error = broken_pipe;
	    ReleaseMutex(Mutex);
	} else { 
	    Error = GetLastError();
	}	
	delete sock;
	return NULL;
    }    
    return sock;
}

bool local_win_socket::cancel_accept() 
{
    state = ss_shutdown;
    SetEvent(Signal[RD]);
    SetEvent(Signal[RTT]);
    return true;
}    

char* local_win_socket::get_peer_name()
{
    if (state != ss_open) { 
	Error = not_opened;
	return NULL;
    }
    char* addr = "127.0.0.1";
    char* addr_copy = new char[strlen(addr)+1];
    strcpy(addr_copy, addr);
    Error = ok;
    return addr_copy;
}

bool local_win_socket::is_ok()
{
    return !Error;
}

bool local_win_socket::close()
{
    if (state != ss_close) { 		
	state = ss_close;
	if (Mutex) { 
	    CloseHandle(Mutex);
	}
	for (int i = RD; i <= RTT; i++) { 
	    CloseHandle(Signal[i]);
        }
	UnmapViewOfFile(RcvBuf < SndBuf ? RcvBuf : SndBuf);
        CloseHandle(BufHnd);	
	Error = not_opened;
    }
    return true;
}

void local_win_socket::get_error_text(char* buf, size_t buf_size)
{
    switch (Error) { 
      case ok:
        strncpy(buf, "ok", buf_size);
	break;
      case not_opened:
        strncpy(buf, "socket not opened", buf_size);
	break;
      case broken_pipe:
        strncpy(buf, "connection is broken", buf_size);
	break;
      case timeout_expired:
        strncpy(buf, "connection timeout expired", buf_size);
	break;
      default: 	
#ifndef PHAR_LAP
	FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM,
		      NULL,
		      Error,
		      0,
		      buf,
		      buf_size,
		      NULL);
#else
	strncpy(buf, "Unknown socket error", buf_size);
#endif
    }
}


bool local_win_socket::shutdown()
{
    if (state == ss_open) { 
    	state = ss_shutdown;
	SetEvent(Signal[RD]); 	
	SetEvent(Signal[RTT]); 	
    }
    return true;
}

bool local_win_socket::connect(int max_attempts, time_t timeout)
{
    char buf[MAX_ADDRESS_LEN];
    int  rc, i, error_code;
    HANDLE h[2];

    for (i = RD; i <= RTT; i++) {  
        sprintf(buf, "%s.%c", Name, ((i + TD - RD) & RTT) + '0');
	Signal[i] = CreateEvent(FASTDB_SECURITY_ATTRIBUTES, false, false, buf);
	if (!Signal[i]) {
	    Error = GetLastError();
	    while (--i >= 0) { 
		CloseHandle(Signal[i]);
            }
	    return false;
        }	
    }
    sprintf(buf, "%s.shr", Name);
    BufHnd = CreateFileMapping(INVALID_HANDLE_VALUE, FASTDB_SECURITY_ATTRIBUTES, PAGE_READWRITE,
                               0, sizeof(socket_buf)*2, buf);
    if (!BufHnd) {
	Error = GetLastError();
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	return false;
    }
    SndBuf = (socket_buf*)MapViewOfFile(BufHnd, FILE_MAP_ALL_ACCESS, 0, 0, 0);
    if (!SndBuf) { 
	Error = GetLastError();
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	CloseHandle(BufHnd);
	return false;
    }
    RcvBuf = SndBuf+1;
    state = ss_shutdown;
    Mutex = NULL;

    rc = WaitForSingleObject(Signal[RTT],timeout*max_attempts*MILLISECOND);
    if (rc != WAIT_OBJECT_0) {
	error_code = rc == WAIT_TIMEOUT ? timeout_expired : GetLastError();
	close();
	Error = error_code;
	return false;
    }
    connect_data* cdp = (connect_data*)RcvBuf->Data;
    HANDLE hServer = OpenProcess(STANDARD_RIGHTS_REQUIRED|PROCESS_DUP_HANDLE,
				 false, cdp->Pid);
    if (!hServer) { 
	error_code = GetLastError();
	close();
	Error = error_code;
	return false;
    }
    HANDLE hSelf = GetCurrentProcess();
    if (!DuplicateHandle(hServer, cdp->Mutex, hSelf, &Mutex, 
			 0, false, DUPLICATE_SAME_ACCESS) ||
	!DuplicateHandle(hSelf, WatchDogMutex, hServer, 
			 &((connect_data*)SndBuf->Data)->Mutex, 
			 0, false, DUPLICATE_SAME_ACCESS))
    {
        error_code = GetLastError();
	CloseHandle(hServer);
	close();
	Error = error_code;
	return false;
    }
    SetEvent(Signal[TD]);
    h[0] = Signal[RD];
    h[1] = Mutex;
    rc = WaitForMultipleObjects(2, h, false, INFINITE);

    if (rc != WAIT_OBJECT_0) { 
	if (rc == WAIT_OBJECT_0+1 || rc == WAIT_ABANDONED+1) { 
	    error_code = broken_pipe;
	    ReleaseMutex(Mutex);
	} else { 
	    error_code = GetLastError();
	}
	CloseHandle(hServer);
	close();
	Error = error_code;
	return false;
    }
    accept_data ad = *(accept_data*)RcvBuf->Data;

    SetEvent(Signal[TD]);
    for (i = RD; i <= RTT; i++) { 
	CloseHandle(Signal[i]);
    }
    UnmapViewOfFile(SndBuf);
    CloseHandle(BufHnd);	
    BufHnd = NULL;

    if (!DuplicateHandle(hServer, ad.BufHnd, hSelf, &BufHnd, 
			 0, false, DUPLICATE_SAME_ACCESS))
    {
	Error = GetLastError();
	CloseHandle(hServer);
	CloseHandle(Mutex); 
	return false;
    } else { 
	for (i = RD; i <= RTT; i++) { 
	    if (!DuplicateHandle(hServer, ad.Signal[i], 
				 hSelf, &Signal[i], 
				 0, false, DUPLICATE_SAME_ACCESS))
	    {
		Error = GetLastError();
		CloseHandle(hServer);
		CloseHandle(BufHnd); 
		CloseHandle(Mutex); 
		while (--i >= 0) CloseHandle(Signal[1]);
		return false;
	    }
	}
    }
    CloseHandle(hServer);

    SndBuf = (socket_buf*)MapViewOfFile(BufHnd, FILE_MAP_ALL_ACCESS, 0, 0, 0);
    if (!SndBuf) { 
	Error = GetLastError();
	CloseHandle(BufHnd); 
	CloseHandle(Mutex); 
	for (i = RD; i <= RTT; i++) {  
	    CloseHandle(Signal[i]);
        }
	return false;
    }
    RcvBuf = SndBuf+1;
    Error = ok;
    state = ss_open; 
    return true;
}

int local_win_socket::get_handle()
{
    return -1;
}