socklib.c

vxworks源码源码解读是学习vxworks的最佳途径

/* sockLib.c - generic socket library */

/* Copyright 1984 - 1999 Wind River Systems, Inc. */
#include "copyright_wrs.h"

/*
modification history
--------------------
04p,16mar99,spm  recovered orphaned code from tor2_0_x branch (SPR #25770)
04o,02dec98,n_s  updated comments for sendmsg and recvmsg. spr 23552
04n,10nov98,spm  changed socket map for removal of closed files (SPR #21583)
04n,15mar99,c_c  Doc: Updated setsockopt () with SO_DEBUG flag (SPR #9636).
04m,14dec97,jdi  doc: cleanup.
04l,10dec97,kbw  fixed man page problems 
04k,04aug97,kbw  fixed man page problems found in beta review
04j,15apr97,kbw  fixed minor man page format problems
04i,14arp97,vin  added changes to setsockopt docs.
04l,14jul97,dgp  doc: change ^C to CTRL-C in setsockopt()
04k,10jul97,dgp  doc: fix SPRs 8470 & 8471, parameters of getsockopt()
04j,31jul95,dzb  check for lib init in sockLibAdd() and socket().
04i,25jul95,dzb  added fd-to-pSockFunc table.  added sockLibAdd().
04h,21jul95,dzb  changed to be a BSD/STREAMS switchyard.
		 Previous sockLib.c file moved to bsdSockLib.c.
04i,26oct95,rhp  doc: mention values for <flags> params in socket
                 calls (SPR#4423)
04h,14oct95,jdi  doc: revised pathnames for Tornado.
04g,13mar95,dzb  added spl semaphore protection to socket() (SPR #4016).
04f,11feb95,jdi  doc format repairs.
04e,18jan95,jdi  doc cleanup for connectWithTimeout().
04d,14not94,rhp  added socket-option documentation to setsockopt man page,
                 and added pointers from send() and sendto() (SPR#3785);
                 specified no support for UNIX Domain sockets (SPR#3519,1432)
04c,18aug94,dzb  Removed the NOMANUAL from connectWithTimeout() (SPR #3550).
                 Added m_freem() calls for mbuf interface (MSG_MBUF).
04b,22apr93,caf  ansification: added cast to ioctl() parameter.
04a,11aug93,jmm  Changed ioctl.h and socket.h to sys/ioctl.h and sys/socket.h
03z,01mar93,jdi  doc: addition of ioctl() functions (SPR 1922); added
		 explanation of accept() parameters (SPR 1382).
03y,03feb93,jdi  documentation cleanup for 5.1.
03x,19aug92,smb  changed systime.h to sys/times.h.
03w,26may92,rrr  the tree shuffle
03v,04oct91,rrr  passed through the ansification filter
                  -changed functions to ansi style
		  -changed includes to have absolute path from h/
		  -changed copyright notice
03u,30apr91,jdi	 documentation tweaks.
03t,05apr91,jdi	 documentation -- removed header parens and x-ref numbers;
		 doc review by dnw.
03s,24mar91,jaa  documentation cleanup.
03r,07feb91,elh  changed recvfrom to check if from is NULL before filling it.
03q,31jan91,jaa	 documentation.
03p,25oct90,dnw  changed utime.h to systime.h.
03o,04oct90,shl  made connectWithTimeOut() NOMANUAL.
03n,02oct90,hjb  eliminated a race and a bug in sockClose().
03m,25may90,dnw  removed malloc of file name "(socket)" before calling iosFdSet.
		 added "(socket)" as device name for iosFdSet optimization.
03l,11may90,yao  added missing modification history (03k) for the last checkin.
03k,09may90,yao  typecasted malloc to (char *).
03j,07may90,hjb  added sockFdVerify(), connectWithTimeout(), a hack to avoid
		 register d2 trashing bug.
03i,19apr90,hjb  deleted sendit(), recvit() and modified sendmsg() and
		 recvmsg() accordingly, de-linted.
03h,18mar90,hjb  optimization of send(), sendto(), sockWrite(), recv(),
		 recvfrom(), sockRead().
03g,16mar90,rdc  removed polling version of select.
03f,09jun89,gae  cleanup of 03e.
03e,07jun89,gae  changed SOCKADDR back to "struct sockaddr".
03d,24may89,hjb  fixed a bug in bind(); when sobind() fails, we now free
		 the allocated mbuf before returning error code.
03c,14apr89,gae  made select backward compatible with BSD 4.2, fixed bug,
		 made time of 0 not actually delay, more optimizing.
03b,13apr89,rdc  made select detect passively closed sockets.
		 installed marc ullman's select optimizations.
03a,15oct88,dnw  changed call to sleep() to ksleep().
02z,13sep88,llk  Fixed bug in select.  Now it polls at least once at all times.
02y,26aug88,gae  lint.
02x,18aug88,gae  documentation.
02w,15jul88,llk  changed to malloc the name of a socket fd before calling
		   iosFdNew.
02v,22jun88,dnw  changed apparent socket filename from "(network)" to "(socket)"
02u,30may88,dnw  changed to v4 names.
02t,28may88,dnw  removed setNetStatus to netLib.
02s,04may88,jcf  changed so_timeoSem to so_timeoSemId
	   +ecs  fixed bug in select introduced in 02r.
02r,30mar88,gae  made mainly iosLib independent.  Cleaned up select(),
		   made it use BSD4.3 fd_set's and caught small bug.
02q,27jan88,jcf  made kernel independent.
02p,05jan88,rdc  added include of sysm.h
02o,14dec87,gae  added include of vxWorks.h!!!
02n,18nov87,ecs  documentation.
02m,17nov87,rdc  fixed documentation for setsockopt.
02l,04nov87,dnw  fixed warning from missing coercion in sendto.
02k,03nov87,rdc  added shutdown, cleaned up documentation.
02j,13oct87,rdc  added select, setSelectDelay. make setNetStatus not be LOCAL.
02i,30sep87,gae  removed use of fdTable by replacing with calls to iosFdSet().
02h,02may87,dnw  removed unnecessary includes.
02g,01apr87,ecs  fixed bugs in getsockname & getpeername (found by lint!)
		 changed references to "struct sockaddr" to "SOCKADDR".
02f,26mar87,rdc  made sendit and recvit call splnet first thing.
02e,23mar87,jlf  documentation.
02d,30jan87,rdc  added getsockname and getpeername.
		 sendit and recvit weren't always calling setNetStatus.
02c,24dec86,gae  changed stsLib.h to vwModNum.h.
02b,08nov86,dnw  fixed bug in closeSock of not freeing fd.
02a,15oct86,rdc  completely rewritten for new 4.3 network code.
01i,04sep86,jlf  minor documentation.
		 made listen return OK always.
01h,01jul86,jlf  minor documentation
01g,18jun86,rdc  delinted.
01f,29apr86,rdc  changed memAllocates to mallocs and de-linted.
		 Added getsockopt and setsockopt to implement KEEP_ALIVE.
01e,09apr86,rdc  all linked list code now uses lstLib.
		 added sockCloseAll and sockNumActive.
01d,28jan86,jlf  documentation
01c,20nov85,rdc  fixed accept to be 4.2 like
01b,08oct85,rdc  de-linted
01a,03oct85,rdc  written
*/

/*
This library provides UNIX BSD 4.4 compatible socket calls.  Use these 
calls to open, close, read, and write sockets. These sockets can join 
processes on the same CPU or on different CPUs between which there is a
network connection.  The calling sequences of these routines are identical 
to their equivalents under UNIX BSD 4.4.

ADDRESS FAMILY
VxWorks sockets support only the Internet Domain address family.  Use
AF_INET for the <domain> argument in subroutines that require it.
There is no support for the UNIX Domain address family.

IOCTL FUNCTIONS
Sockets respond to the following ioctl() functions.  These functions are
defined in the header files ioLib.h and ioctl.h.
.IP 'FIONBIO' 15 
Turns on/off non-blocking I/O.
.CS
    on = TRUE;
    status = ioctl (sFd, FIONBIO, &on);
.CE
.IP 'FIONREAD'
Reports the number of read-ready bytes available on the socket.  On the 
return of ioctl(), <bytesAvailable> has the number of bytes available to 
read from the socket.
.CS
    status = ioctl (sFd, FIONREAD, &bytesAvailable);
.CE
.IP 'SIOCATMARK'
Reports whether there is out-of-band data to be read from the socket.  On
the return of ioctl(), <atMark> is TRUE (1) if there is out-of-band
data.  Otherwise, it is FALSE (0).
.CS
    status = ioctl (sFd, SIOCATMARK, &atMark);
.CE

INCLUDE FILES: types.h, mbuf.h, socket.h, socketvar.h

SEE ALSO: netLib,
.pG "Network"
*/

/* includes */

#include "vxWorks.h"
#include "stdlib.h"
#include "iosLib.h"
#include "netLib.h"
#include "errnoLib.h"
#include "sockFunc.h"
#include "sockLib.h"

/* typedefs */

typedef struct sockLibMap
    {
    int			domainMap;	/* mapping address family  */
    int			domainReal;	/* real address family     */
    SOCK_FUNC *		pSockFunc;	/* socket function table   */
    struct sockLibMap *	pNext;		/* next socket lib mapping */
    } SOCK_LIB_MAP;

/* globals */

SOCK_FUNC ** 	pSockFdMap = NULL;

/* locals */

LOCAL SOCK_LIB_MAP *	pSockLibMapH = NULL;

/*******************************************************************************
*
* sockLibInit - initialize a socket library back-end library.
*
* RETURNS: OK, or ERROR if the back-end could not be initialized.
*
* NOMANUAL
*/

STATUS sockLibInit
    (
    int		fdMax			/* maximum file descriptors */
    )
    {
    if (pSockFdMap != NULL)		/* already initialized ? */
	return (OK);

    /* allocate fd-to-pSockFunc mapping array */

    if ((pSockFdMap = (SOCK_FUNC **) calloc (1, fdMax *
	sizeof (SOCK_FUNC **))) == NULL)
	return (ERROR);

    return (OK);
    }

/*******************************************************************************
*
* sockLibAdd - add a socket library back-end
*
* RETURNS: OK, or ERROR if the socket back-end could not be added.
*
* NOMANUAL
*/

STATUS sockLibAdd
    (
    FUNCPTR	sockLibInitRtn,		/* back-end init routine */
    int		domainMap,		/* address family */
    int		domainReal		/* address family */
    )
    {
    SOCK_LIB_MAP *	pSockLibMap;	/* back-end mapping entry ptr */

    if (pSockFdMap == NULL)		/* initialized yet ? */
	return (ERROR);

    if ((pSockLibMap = (SOCK_LIB_MAP *) malloc (sizeof (SOCK_LIB_MAP))) == NULL)
	return (ERROR);

    /* init socket back-end */

    if ((sockLibInitRtn == NULL) ||
	((pSockLibMap->pSockFunc = (SOCK_FUNC *) (sockLibInitRtn) ()) == NULL))
	{
	free (pSockLibMap);		/* back-end error */
	return (ERROR);
	}

    pSockLibMap->domainMap = domainMap;   /* stuff mapping address family */
    pSockLibMap->domainReal = domainReal; /* stuff real address family */
    pSockLibMap->pNext = pSockLibMapH;    /* hook into lib list */

    pSockLibMapH = pSockLibMap;		/* update lib list head */

    return (OK);
    }

/*******************************************************************************
*
* socket - open a socket
*
* This routine opens a socket and returns a socket descriptor.
* The socket descriptor is passed to the other socket routines to identify the
* socket.  The socket descriptor is a standard I/O system file descriptor
* (fd) and can be used with the close(), read(), write(), and ioctl() routines.
*
* Available socket types include:
* .IP SOCK_STREAM 18
* Specifies a connection-based (stream) socket.
* .IP SOCK_DGRAM
* Specifies a datagram (UDP) socket.
* .IP SOCK_RAW
* Specifies a raw socket.
* .LP
*
* RETURNS: A socket descriptor, or ERROR.
*/

int socket
    (
    int domain,         /* address family (for example, AF_INET) */
    int type,           /* SOCK_STREAM, SOCK_DGRAM, or SOCK_RAW */
    int protocol        /* socket protocol (usually 0) */
    )
    {
    SOCK_LIB_MAP *	pSockLibMap;
    int			newFd;

    if (pSockFdMap == NULL)		/* initialized yet ? */
	return (ERROR);

    /* search for a suitable back-end library entry */

    for (pSockLibMap = pSockLibMapH; (pSockLibMap != NULL) &&
	(pSockLibMap->domainMap != domain); pSockLibMap = pSockLibMap->pNext)
	;

    /* found library map entry ? */

    if ((pSockLibMap == NULL) || (pSockLibMap->pSockFunc->socketRtn == NULL))
	{
	netErrnoSet (ENOTSUP);
	return (ERROR);
	}

    /* call back-end to open a socket */

    if ((newFd = (pSockLibMap->pSockFunc->socketRtn)
	(pSockLibMap->domainReal, type, protocol)) == ERROR)
	return (ERROR);

    pSockFdMap[newFd] = pSockLibMap->pSockFunc;	/* stuff fd map array */

    return (newFd);
    }

/*******************************************************************************
*
* bind - bind a name to a socket
*
* This routine associates a network address (also referred to as its "name")
* with a specified socket so that other processes can connect or send to it.
* When a socket is created with socket(), it belongs to an address family
* but has no assigned name.
*
* RETURNS:
* OK, or ERROR if there is an invalid socket, the address is either
* unavailable or in use, or the socket is already bound.
*/

STATUS bind
    (
    int s,                      /* socket descriptor */
    struct sockaddr *name,      /* name to be bound */
    int namelen                 /* length of name */
    )
    {
    SOCK_FUNC *	pSockFunc = pSockFdMap[s];

    if ((pSockFunc == NULL) || (pSockFunc->bindRtn == NULL))
	{
        netErrnoSet (ENOTSUP);
	return (ERROR);
	}

    return ((pSockFunc->bindRtn) (s, name, namelen));
    }

/*******************************************************************************
*
* listen - enable connections to a socket
*
* This routine enables connections to a socket.  It also specifies the
* maximum number of unaccepted connections that can be pending at one time
* (<backlog>).  After enabling connections with listen(), connections are
* actually accepted by accept().
*
* RETURNS: OK, or ERROR if the socket is invalid or unable to listen.
*/

STATUS listen
    (
    int s,              /* socket descriptor */
    int backlog         /* number of connections to queue */
    )
    {
    SOCK_FUNC *	pSockFunc = pSockFdMap[s];

    if ((pSockFunc == NULL) || (pSockFunc->listenRtn == NULL))
	{
        netErrnoSet (ENOTSUP);
	return (ERROR);
	}

    return ((pSockFunc->listenRtn) (s, backlog));
    }

/*******************************************************************************
*
* accept - accept a connection from a socket
*
* This routine accepts a connection on a socket, and returns a new socket
* created for the connection.  The socket must be bound to an address with
* bind(), and enabled for connections by a call to listen().  The accept()
* routine dequeues the first connection and creates a new socket with the
* same properties as <s>.  It blocks the caller until a connection is
* present, unless the socket is marked as non-blocking.
*
* The parameter <addrlen> should be initialized to the size of the available
* buffer pointed to by <addr>.  Upon return, <addrlen> contains the size in
* bytes of the peer's address stored in <addr>.
*
* RETURNS
* A socket descriptor, or ERROR if the call fails.
*/

int accept
    (
    int s,                      /* socket descriptor */
    struct sockaddr *addr,      /* peer address */
    int *addrlen                /* peer address length */
    )
    {
    SOCK_FUNC *	pSockFunc = pSockFdMap[s];
    int		newFd;

    if ((pSockFunc == NULL) || (pSockFunc->acceptRtn == NULL))
	{
        netErrnoSet (ENOTSUP);
	return (ERROR);
	}

    if ((newFd = (pSockFunc->acceptRtn) (s, addr, addrlen)) == ERROR)