socket.c

bind 9.3结合mysql数据库

/*
 * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2000-2003  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

/* $Id: socket.c,v 1.5.2.13.2.13 2004/09/01 04:32:18 marka Exp $ */

/* This code has been rewritten to take advantage of Windows Sockets
 * I/O Completion Ports and Events. I/O Completion Ports is ONLY
 * available on Windows NT, Windows 2000 and Windows XP series of
 * the Windows Operating Systems. In CANNOT run on Windows 95, Windows 98
 * or the follow-ons to those Systems.
 *
 * This code is by nature multithreaded and takes advantage of various
 * features to pass on information through the completion port for
 * when I/O is completed.  All sends and receives are completed through
 * the completion port. Due to an implementation bug in Windows 2000,
 * Service Pack 2 must installed on the system for this code to run correctly.
 * For details on this problem see Knowledge base article Q263823.
 * The code checks for this. The number of Completion Port Worker threads
 * used is the total number of CPU's + 1. This increases the likelihood that
 * a Worker Thread is available for processing a completed request.
 *
 * All accepts and connects are accomplished through the WSAEventSelect()
 * function and the event_wait loop. Events are added to and deleted from
 * each event_wait thread via a common event_update stack owned by the socket
 * manager. If the event_wait thread runs out of array space in the events
 * array it will look for another event_wait thread to add the event. If it
 * fails to find another one it will create a new thread to handle the
 * outstanding event.
 *
 * A future enhancement is to use AcceptEx to take avantage of Overlapped
 * I/O which allows for enhanced performance of TCP connections.
 * This will also reduce the number of events that are waited on by the
 * event_wait threads to just the connect sockets and reduce the number
 * additional threads required.
 *
 * XXXPDM 5 August, 2002
 */

#define MAKE_EXTERNAL 1
#include <config.h>

#include <sys/types.h>

#ifndef _WINSOCKAPI_
#define _WINSOCKAPI_   /* Prevent inclusion of winsock.h in windows.h */
#endif

#include <errno.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <io.h>
#include <fcntl.h>
#include <process.h>

#include <isc/buffer.h>
#include <isc/bufferlist.h>
#include <isc/condition.h>
#include <isc/list.h>
#include <isc/log.h>
#include <isc/mem.h>
#include <isc/msgs.h>
#include <isc/mutex.h>
#include <isc/net.h>
#include <isc/os.h>
#include <isc/platform.h>
#include <isc/print.h>
#include <isc/region.h>
#include <isc/socket.h>
#include <isc/strerror.h>
#include <isc/syslog.h>
#include <isc/task.h>
#include <isc/thread.h>
#include <isc/util.h>
#include <isc/win32os.h>

#include "errno2result.h"

/*
 * Define this macro to control the behavior of connection
 * resets on UDP sockets.  See Microsoft KnowledgeBase Article Q263823
 * for details.
 * NOTE: This requires that Windows 2000 systems install Service Pack 2
 * or later.
 */
#ifndef SIO_UDP_CONNRESET 
#define SIO_UDP_CONNRESET _WSAIOW(IOC_VENDOR,12) 
#endif

/*
 * Some systems define the socket length argument as an int, some as size_t,
 * some as socklen_t.  This is here so it can be easily changed if needed.
 */
#ifndef ISC_SOCKADDR_LEN_T
#define ISC_SOCKADDR_LEN_T unsigned int
#endif

/*
 * Define what the possible "soft" errors can be.  These are non-fatal returns
 * of various network related functions, like recv() and so on.
 *
 * For some reason, BSDI (and perhaps others) will sometimes return <0
 * from recv() but will have errno==0.  This is broken, but we have to
 * work around it here.
 */
#define SOFT_ERROR(e)	((e) == WSAEINTR || \
			 (e) == WSA_IO_PENDING || \
			 (e) == WSAEWOULDBLOCK || \
			 (e) == EWOULDBLOCK || \
			 (e) == EINTR || \
			 (e) == EAGAIN || \
			 (e) == 0)

#define DLVL(x) ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_SOCKET, ISC_LOG_DEBUG(x)

/*
 * DLVL(90)  --  Function entry/exit and other tracing.
 * DLVL(70)  --  Socket "correctness" -- including returning of events, etc.
 * DLVL(60)  --  Socket data send/receive
 * DLVL(50)  --  Event tracing, including receiving/sending completion events.
 * DLVL(20)  --  Socket creation/destruction.
 */
#define TRACE_LEVEL		90
#define CORRECTNESS_LEVEL	70
#define IOEVENT_LEVEL		60
#define EVENT_LEVEL		50
#define CREATION_LEVEL		20

#define TRACE		DLVL(TRACE_LEVEL)
#define CORRECTNESS	DLVL(CORRECTNESS_LEVEL)
#define IOEVENT		DLVL(IOEVENT_LEVEL)
#define EVENT		DLVL(EVENT_LEVEL)
#define CREATION	DLVL(CREATION_LEVEL)

typedef isc_event_t intev_t;

#define SOCKET_MAGIC		ISC_MAGIC('I', 'O', 'i', 'o')
#define VALID_SOCKET(t)		ISC_MAGIC_VALID(t, SOCKET_MAGIC)

/*
 * IPv6 control information.  If the socket is an IPv6 socket we want
 * to collect the destination address and interface so the client can
 * set them on outgoing packets.
 */
#ifdef ISC_PLATFORM_HAVEIPV6
#ifndef USE_CMSG
#define USE_CMSG	1
#endif
#endif

/*
 * NetBSD and FreeBSD can timestamp packets.  XXXMLG Should we have
 * a setsockopt() like interface to request timestamps, and if the OS
 * doesn't do it for us, call gettimeofday() on every UDP receive?
 */

/*
 * We really  don't want to try and use these control messages. Win32
 * doesn't have this mechanism
 */
#undef USE_CMSG

/*
 * Message header for recvmsg and sendmsg calls.
 * Used value-result for recvmsg, value only for sendmsg.
 */


struct msghdr {
        void	*msg_name;              /* optional address */
        u_int   msg_namelen;            /* size of address */
        WSABUF  *msg_iov;		/* scatter/gather array */
        u_int   msg_iovlen;             /* # elements in msg_iov */
        void	*msg_control;           /* ancillary data, see below */
        u_int   msg_controllen;         /* ancillary data buffer len */
        int     msg_flags;              /* flags on received message */
} msghdr;
	
/*
 * The number of times a send operation is repeated if the result is EINTR.
 */
#define NRETRIES 10

struct isc_socket {
	/* Not locked. */
	unsigned int		magic;
	isc_socketmgr_t	       *manager;
	isc_mutex_t		lock;
	isc_sockettype_t	type;
	OVERLAPPED		overlapped;
	/* Pointers to scatter/gather buffers */
	WSABUF			iov[ISC_SOCKET_MAXSCATTERGATHER];
	size_t			totalBytes;
	WSAEVENT		hEvent;		/* Event Handle */
	long			wait_type;	/* Events to wait on */
	WSAEVENT		hAlert;		/* Alert Event Handle */
	DWORD			evthread_id;	/* Event Thread Id for socket */


	/* Locked by socket lock. */
	ISC_LINK(isc_socket_t)	link;
	unsigned int		references;
	SOCKET			fd;
	int			pf;

	ISC_LIST(isc_socketevent_t)		send_list;
	ISC_LIST(isc_socketevent_t)		recv_list;
	ISC_LIST(isc_socket_newconnev_t)	accept_list;
	isc_socket_connev_t		       *connect_ev;

	/*
	 * Internal events.  Posted when a descriptor is readable or
	 * writable.  These are statically allocated and never freed.
	 * They will be set to non-purgable before use.
	 */
	intev_t			readable_ev;
	intev_t			writable_ev;

	isc_sockaddr_t		address;  /* remote address */

	unsigned int		pending_close : 1,
				pending_accept : 1,
				iocp : 1,	/* I/O Completion Port */
				listener : 1,	/* listener socket */
				connected : 1,
				connecting : 1, /* connect pending */
				bound : 1,	/* bound to local addr */
				pending_free: 1;
	unsigned int		pending_recv;
	unsigned int		pending_send;
};

/*
 * I/O Completion ports Info structures
 */

static HANDLE hHeapHandle = NULL;
static int iocp_total = 0;
typedef struct IoCompletionInfo {
	OVERLAPPED			overlapped;
	isc_socketevent_t		*dev;
	int				request_type;
	struct msghdr			messagehdr;
} IoCompletionInfo;

/*
 * Define a maximum number of I/O Completion Port worker threads
 * to handle the load on the Completion Port. The actual number
 * used is the number of CPU's + 1.
 */
#define MAX_IOCPTHREADS 20

/*
 * event_change structure to handle adds and deletes from the list of
 * events in the Wait
 */
typedef struct event_change event_change_t;

struct event_change {
	isc_socket_t			*sock;
	WSAEVENT			hEvent;
	DWORD				evthread_id;
	SOCKET				fd;
	unsigned int			action;
	ISC_LINK(event_change_t)	link;
};

/*
 * Note: We are using an array here since *WaitForMultiple* wants an array
 * WARNING: This value may not be greater than 64 since the 
 * WSAWaitForMultipleEvents function is limited to 64 events.
 */

#define MAX_EVENTS 64

/*
 * List of events being waited on and their associated sockets
 */
typedef struct sock_event_list {
	int max_event;
	int total_events;
	isc_socket_t			*aSockList[MAX_EVENTS];
	WSAEVENT			aEventList[MAX_EVENTS];
} sock_event_list;

/*
 * Thread Event structure for managing the threads handling events
 */
typedef struct events_thread events_thread_t;

struct events_thread {
	isc_thread_t			thread_handle;	/* Thread's handle */
	DWORD				thread_id;	/* Thread's id */
	sock_event_list			sockev_list;
	isc_socketmgr_t			*manager;
	ISC_LINK(events_thread_t)	link;
};

#define SOCKET_MANAGER_MAGIC	ISC_MAGIC('I', 'O', 'm', 'g')
#define VALID_MANAGER(m)	ISC_MAGIC_VALID(m, SOCKET_MANAGER_MAGIC)

struct isc_socketmgr {
	/* Not locked. */
	unsigned int			magic;
	isc_mem_t		       *mctx;
	isc_mutex_t			lock;
	/* Locked by manager lock. */
	ISC_LIST(event_change_t)	event_updates;
	ISC_LIST(isc_socket_t)		socklist;
	int				event_written;
	WSAEVENT			prime_alert;
	isc_boolean_t			bShutdown;
	ISC_LIST(events_thread_t)	ev_threads;
	isc_condition_t			shutdown_ok;
	HANDLE				hIoCompletionPort;
	int				maxIOCPThreads;
	HANDLE				hIOCPThreads[MAX_IOCPTHREADS];
	DWORD				dwIOCPThreadIds[MAX_IOCPTHREADS];
};

#define CLOSED		0	/* this one must be zero */
#define MANAGED		1
#define CLOSE_PENDING	2

/*
 * send() and recv() iovec counts
 */
#define MAXSCATTERGATHER_SEND	(ISC_SOCKET_MAXSCATTERGATHER)
#define MAXSCATTERGATHER_RECV	(ISC_SOCKET_MAXSCATTERGATHER)

static isc_threadresult_t WINAPI event_wait(void *uap);
static isc_threadresult_t WINAPI SocketIoThread(LPVOID ThreadContext);
static void free_socket(isc_socket_t **);

enum {
	SOCKET_RECV,
	SOCKET_SEND,
};

enum {
	EVENT_ADD,
	EVENT_DELETE
};

#if defined(ISC_SOCKET_DEBUG)
/*
 * This is used to dump the contents of the sock structure
 * You should make sure that the sock is locked before
 * dumping it. Since the code uses simple printf() statements
 * it should only be used interactively.
 */
void
sock_dump(isc_socket_t *sock) {
	isc_socketevent_t *ldev;
	isc_socket_newconnev_t *ndev;
	isc_sockaddr_t addr;
	char socktext[256];


	isc_socket_getpeername(sock, &addr);
	isc_sockaddr_format(&addr, socktext, sizeof(socktext));
	printf("Remote Socket: %s\n", socktext);
	isc_socket_getsockname(sock, &addr);
	isc_sockaddr_format(&addr, socktext, sizeof(socktext));
	printf("This Socket: %s\n", socktext);

	printf("\n\t\tSock Dump\n");
	printf("\t\tfd: %u\n", sock->fd);
	printf("\t\treferences: %d\n", sock->references);
	printf("\t\tpending_accept: %d\n", sock->pending_accept);
	printf("\t\tpending_close: %d\n", sock->pending_close);
	printf("\t\tconnecting: %d\n", sock->connecting);
	printf("\t\tconnected: %d\n", sock->connected);
	printf("\t\tbound: %d\n", sock->bound);
	printf("\t\tiocp: %d\n", sock->iocp);
	printf("\t\tsocket type: %d\n", sock->type);

	printf("\n\t\tSock Recv List\n");
	ldev = ISC_LIST_HEAD(sock->recv_list);
	while (ldev != NULL) {
		printf("\t\tdev: %p\n", ldev);
		ldev = ISC_LIST_NEXT(ldev, ev_link);
	}
	printf("\n\t\tSock Send List\n");
	ldev = ISC_LIST_HEAD(sock->send_list);
	while (ldev != NULL) {
		printf("\t\tdev: %p\n", ldev);
		ldev = ISC_LIST_NEXT(ldev, ev_link);
	}
	printf("\n\t\tSock Accept List\n");
	ndev = ISC_LIST_HEAD(sock->accept_list);
	while (ndev != NULL) {
		printf("\t\tdev: %p\n", ldev);
		ndev = ISC_LIST_NEXT(ndev, ev_link);
	}
}
#endif

/*  This function will add an entry to the I/O completion port
 *  that will signal the I/O thread to exit (gracefully)
 */
static void
signal_iocompletionport_exit(isc_socketmgr_t *manager) {
	int i;
	int errval;
	char strbuf[ISC_STRERRORSIZE];

	REQUIRE(VALID_MANAGER(manager));
	for (i = 0; i < manager->maxIOCPThreads; i++) {
		if (!PostQueuedCompletionStatus(manager->hIoCompletionPort,
						0, 0, 0)) {
			errval = GetLastError();
			isc__strerror(errval, strbuf, sizeof(strbuf));
			FATAL_ERROR(__FILE__, __LINE__,
				isc_msgcat_get(isc_msgcat, ISC_MSGSET_SOCKET,
				ISC_MSG_FAILED,
				"Can't request service thread to exit: %s"),
				strbuf);
		}
	}
}

/*
 * Create the worker threads for the I/O Completion Port
 */
void
iocompletionport_createthreads(int total_threads, isc_socketmgr_t *manager) {
	int errval;
	char strbuf[ISC_STRERRORSIZE];
	int i;

	INSIST(total_threads > 0);
	REQUIRE(VALID_MANAGER(manager));
	/*
	 * We need at least one
	 */
	for (i = 0; i < total_threads; i++) {
		manager->hIOCPThreads[i] = CreateThread(NULL, 0, SocketIoThread,
						manager, 0,
						&manager->dwIOCPThreadIds[i]);
		if(manager->hIOCPThreads[i] == NULL) {
			errval = GetLastError();
			isc__strerror(errval, strbuf, sizeof(strbuf));
			FATAL_ERROR(__FILE__, __LINE__,
				isc_msgcat_get(isc_msgcat, ISC_MSGSET_SOCKET,
				ISC_MSG_FAILED,
				"Can't create IOCP thread: %s"),
				strbuf);
		}
	}
}

/*
 *  Create/initialise the I/O completion port
 */
void
iocompletionport_init(isc_socketmgr_t *manager) {
	int errval;
	char strbuf[ISC_STRERRORSIZE];

	REQUIRE(VALID_MANAGER(manager));
	/*
	 * Create a private heap to handle the socket overlapped structure
	 * The miniumum number of structures is 10, there is no maximum
	 */
	hHeapHandle = HeapCreate(0, 10*sizeof(IoCompletionInfo), 0);
	manager->maxIOCPThreads = min(isc_os_ncpus() + 1,
					MAX_IOCPTHREADS);

	/* Now Create the Completion Port */
	manager->hIoCompletionPort = CreateIoCompletionPort(
				     INVALID_HANDLE_VALUE, NULL,
				     0, manager->maxIOCPThreads);
	if (manager->hIoCompletionPort == NULL) {
		errval = GetLastError();
		isc__strerror(errval, strbuf, sizeof(strbuf));
		FATAL_ERROR(__FILE__, __LINE__,
				isc_msgcat_get(isc_msgcat, ISC_MSGSET_SOCKET,
				ISC_MSG_FAILED,
				"CreateIoCompletionPort() failed "
				"during initialization: %s"),
				strbuf);
		exit(1);
	}
	
	/*