w32sock.cpp

实现内存数据库的源代码

//-< W32SOCK.CXX >---------------------------------------------------*--------*
// FastDB                    Version 1.0         (c) 1997  GARRET    *     ?  *
// (Main Memory Database Management System)                          *   /\|  *
//                                                                   *  /  \  *
//                          Created:      8-May-97    K.A. Knizhnik  * / [] \ *
//                          Last update: 19-May-97    K.A. Knizhnik  * GARRET *
//-------------------------------------------------------------------*--------*
// Windows sockets  
//-------------------------------------------------------------------*--------*

#define INSIDE_FASTDB

#include "stdtp.h"
#pragma hdrstop
#include "w32sock.h"

#define MAX_HOST_NAME         256
#define MILLISECOND           1000

static HANDLE WatchDogMutex;

#ifdef ASM_CPUID_NOT_SUPPORTED
static CRITICAL_SECTION cs;
#endif

class win_socket_library { 
  public:
    SYSTEM_INFO sinfo;
    
    win_socket_library() { 
	WSADATA wsa;
	if (WSAStartup(MAKEWORD(1, 1), &wsa) != 0) {
	    fprintf(stderr,"Failed to initialize windows sockets: %d\n",
		    WSAGetLastError());
	}
	//
	// This mutex is used to recognize process termination
	//
	WatchDogMutex = CreateMutex(NULL, TRUE, NULL);

#ifdef PHAR_LAP
	sinfo.wProcessorLevel = 5;
#else
	GetSystemInfo(&sinfo);	
#endif
#ifdef ASM_CPUID_NOT_SUPPORTED
	InitializeCriticalSection(&cs);
#endif
    }
    ~win_socket_library() {
#ifdef ASM_CPUID_NOT_SUPPORTED
	DeleteCriticalSection(&cs);
#endif
	//	WSACleanup();
    }
};

static win_socket_library ws32_lib;

inline void serialize() { 
#ifndef ASM_CPUID_NOT_SUPPORTED
    if (ws32_lib.sinfo.wProcessorLevel >= 5) { // Pemtium or higher 
	__asm CPUID;
    }
#else
    EnterCriticalSection(&cs);
    LeaveCriticalSection(&cs);
#endif
}

bool win_socket::open(int listen_queue_size)
{
    unsigned short port;
    char* p;
    char hostname[MAX_HOST_NAME];

    assert(address != NULL);

    if ((p = strchr(address, ':')) == NULL 
	|| sscanf(p+1, "%hu", &port) != 1) 
    {
	errcode = bad_address;
	return false;
    }
    memcpy(hostname, address, p - address);
    hostname[p - address] = '\0';

    if ((s = socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) { 
	errcode = WSAGetLastError();
	return false;
    }
    struct sockaddr_in insock;
    insock.sin_family = AF_INET;
    if (*hostname && stricmp(hostname, "localhost") != 0) {
	struct hostent* hp;  // entry in hosts table
	if ((hp = gethostbyname(hostname)) == NULL 
	    || hp->h_addrtype != AF_INET) 
	{
	    errcode = bad_address;
	    return false;
	}
	memcpy(&insock.sin_addr, hp->h_addr, sizeof insock.sin_addr);
    } else {
	insock.sin_addr.s_addr = htonl(INADDR_ANY);
    }
    insock.sin_port = htons(port);

    int on = 1;
    setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&on, sizeof on);
    
    if (bind(s, (sockaddr*)&insock, sizeof(insock)) != 0) { 
	errcode = WSAGetLastError();
	closesocket(s);
	return false;
    }
    if (listen(s, listen_queue_size) != 0) {
	errcode = WSAGetLastError();
	closesocket(s);
	return false;
    } 
    errcode = ok;
    state = ss_open;
    return true;
}

bool win_socket::is_ok()
{
    return errcode == ok;
}

void win_socket::get_error_text(char* buf, size_t buf_size)
{
    char* msg; 
    char  msgbuf[64];

    switch(errcode) { 
      case ok:
        msg = "ok";
	break;
      case not_opened:
	msg = "socket not opened";
        break;
      case bad_address: 
	msg = "bad address";
	break;
      case connection_failed: 
	msg = "exceed limit of attempts of connection to server";
	break;
      case broken_pipe:
	msg = "connection is broken";
	break; 
      case invalid_access_mode:
        msg = "invalid access mode";
	break;
      default: 
#ifndef PHAR_LAP
        {
	  int   len;
	  len = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM,
	   	              NULL,
		              errcode,
		              0,
		              buf,
		              buf_size,
		              NULL);
	  if (len == 0) { 
              sprintf(msgbuf, "unknown error code %u", errcode);
	      msg = msgbuf;
	  } else { 
	      return;
	  }
        }
#else
	sprintf(msgbuf, "System error code: %u", errcode);
	msg = msgbuf;
#endif
    }
    strncpy(buf, msg, buf_size);
}

socket_t* win_socket::accept()
{
    if (state != ss_open) { 
	errcode = not_opened;
	return NULL;
    }

    SOCKET new_sock = ::accept(s, NULL, NULL );

    if (new_sock == INVALID_SOCKET) { 
	errcode = WSAGetLastError();
	return NULL;
    } else { 
	static struct linger l = {1, LINGER_TIME};
	if (setsockopt(new_sock, SOL_SOCKET, SO_LINGER, (char*)&l, sizeof l) != 0) { 
	    errcode = invalid_access_mode; 
	    closesocket(new_sock);
	    return NULL; 
	}
	int enabled = 1;
	if (setsockopt(new_sock, IPPROTO_TCP, TCP_NODELAY, (char*)&enabled, 
		       sizeof enabled) != 0)
	{
	    errcode = WSAGetLastError();
	    closesocket(new_sock);	
	    return NULL;
	}
	errcode = ok;
	return new win_socket(new_sock); 
    }
}

bool win_socket::cancel_accept() 
{
    bool result = close();
    // Wakeup listener
    delete socket_t::connect(address, sock_global_domain, 1, 0);
    return result;
}    


bool win_socket::connect(int max_attempts, time_t timeout)
{
    char hostname[MAX_HOST_NAME];
    char *p;
    unsigned short port;

    assert(address != NULL);

    if ((p = strchr(address, ':')) == NULL 
	|| p - address >= sizeof(hostname) 
	|| sscanf(p+1, "%hu", &port) != 1) 
    {
	errcode = bad_address;
	return false;
    }
    memcpy(hostname, address, p - address);
    hostname[p - address] = '\0';

    struct sockaddr_in insock;  // inet socket address
    struct hostent*    hp;      // entry in hosts table

    if ((hp = gethostbyname(hostname)) == NULL || hp->h_addrtype != AF_INET) {
	errcode = bad_address;
	return false;
    }
    insock.sin_family = AF_INET;
    insock.sin_port = htons(port);
    
    while (true) {
	for (int i = 0; hp->h_addr_list[i] != NULL; i++) { 
	    memcpy(&insock.sin_addr, hp->h_addr_list[i],
		   sizeof insock.sin_addr);
	    if ((s = socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) { 
		errcode = WSAGetLastError();
		return false;
	    }
	    if (::connect(s, (sockaddr*)&insock, sizeof insock) != 0) { 
		errcode = WSAGetLastError();
		closesocket(s);
		if (errcode != WSAECONNREFUSED) {
		    return false;
		}
	    } else {
		int enabled = 1;
		if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char*)&enabled, 
			       sizeof enabled) != 0)
		{
		    errcode = WSAGetLastError();
		    closesocket(s);	
		    return false;
		}
		errcode = ok;
		state = ss_open;
		return true;
	    }
	}
	if (--max_attempts > 0) {  
	    Sleep(timeout*MILLISECOND);
	} else { 
	    errcode = connection_failed;
	    return false;
	}
    }
}

int win_socket::read(void* buf, size_t min_size, size_t max_size, 
		     time_t timeout)
{ 
    size_t size = 0;
    time_t start = 0;
    if (state != ss_open) { 
	errcode = not_opened;
	return -1;
    }
    if (timeout != WAIT_FOREVER) { 
	start = time(NULL); 
    }

    do { 
	int rc;
	if (timeout != WAIT_FOREVER) { 
	    fd_set events;
	    struct timeval tm;
	    FD_ZERO(&events);
	    FD_SET(s, &events);
	    tm.tv_sec = timeout;
	    tm.tv_usec = 0;
	    rc = select(s+1, &events, NULL, NULL, &tm);
	    if (rc < 0) { 
		errcode = WSAGetLastError();
		return -1;
	    }
	    if (rc == 0) {
		return size;
	    }
	    time_t now = time(NULL);
	    timeout = start + timeout >= now ? timeout + start - now : 0;  
	}
	rc = recv(s, (char*)buf + size, max_size - size, 0);
	if (rc < 0) { 
	    errcode = WSAGetLastError();
	    return -1;
	} else if (rc == 0) {
	    errcode = broken_pipe;
	    return -1; 
	} else { 
	    size += rc; 
	}
    } while (size < min_size); 

    return (int)size;
}
	
bool win_socket::write(void const* buf, size_t size)
{ 
    if (state != ss_open) { 
	errcode = not_opened;
	return false;
    }
    
    do { 
	int rc = send(s, (char*)buf, size, 0);
	if (rc < 0) { 
	    errcode = WSAGetLastError();
	    return false;
	} else if (rc == 0) {
	    errcode = broken_pipe;
	    return false; 
	} else { 
	    buf = (char*)buf + rc; 
	    size -= rc; 
	}
    } while (size != 0); 

    return true;
}
	
bool win_socket::shutdown()
{
    if (state == ss_open) { 
	state = ss_shutdown;
        int rc = ::shutdown(s, 2);
        if (rc != 0) {
	    errcode = WSAGetLastError();
	    return false;
	} 
    } 
    errcode = ok;
    return true;
}


bool win_socket::close()
{
    if (state != ss_close) { 
	state = ss_close;
	if (closesocket(s) == 0) { 
	    errcode = ok;
	    return true;
	} else { 
	    errcode = WSAGetLastError();
	    return false;
	}
    }
    return true;
}

char* win_socket::get_peer_name()
{
    if (state != ss_open) { 
	errcode = not_opened;
	return NULL;
    }
    struct sockaddr_in insock;
    int len = sizeof(insock);
    if (getpeername(s, (struct sockaddr*)&insock, &len) != 0) { 
	errcode = WSAGetLastError();
	return NULL;
    }
    char* addr = inet_ntoa(insock.sin_addr);
    if (addr == NULL) { 
	errcode = WSAGetLastError();
	return NULL;
    }
    char* addr_copy = new char[strlen(addr)+1];
    strcpy(addr_copy, addr);
    errcode = ok;
    return addr_copy;
}

win_socket::~win_socket()
{
    close();
    delete[] address;
}

win_socket::win_socket(const char* addr)
{ 
    address = new char[strlen(addr)+1];
    strcpy(address, addr); 
    errcode = ok;
    s = INVALID_SOCKET;
}

win_socket::win_socket(SOCKET new_sock) 
{ 
    s = new_sock; 
    address = NULL; 
    state = ss_open;
    errcode = ok;
}

socket_t* socket_t::create_local(char const* address, int listen_queue_size)
{
    local_win_socket* sock = new local_win_socket(address);
    sock->open(listen_queue_size);
    return sock;
}

socket_t* socket_t::create_global(char const* address, int listen_queue_size)
{
    win_socket* sock = new win_socket(address);
    sock->open(listen_queue_size); 
    return sock;
}

socket_t* socket_t::connect(char const* address, 
			    socket_domain domain, 
			    int max_attempts,
			    time_t timeout)
{
    char   hostname[MAX_HOST_NAME];
    size_t hostname_len;
    char const* port;
    
    if (domain == sock_local_domain 
	|| (domain == sock_any_domain 
	    && ((port = strchr(address, ':')) == NULL 
		|| ((hostname_len = port - address) == 9 
		    && strncmp(address, "localhost", hostname_len) == 0)
		|| (gethostname(hostname, sizeof hostname) != 0 
		    && strlen(hostname) == hostname_len 
		    && strncmp(address, hostname, hostname_len) == 0))))
     {
        local_win_socket* s = new local_win_socket(address);
        s->connect(max_attempts, timeout); 
	return s;
     } else { 
        win_socket* s = new win_socket(address);
        s->connect(max_attempts, timeout); 
        return s;
    }  
}
    
//
// 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;