bsNullServer.c File Reference

BotSense bsProxy server plug-in DLL /dev/null device module. More...

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "rnr/rnrconfig.h"
#include "rnr/log.h"
#include "rnr/new.h"
#include "rnr/netmsgs.h"
#include "botsense/BotSense.h"
#include "botsense/libBotSense.h"
#include "botsense/bsProxyModIF.h"
#include "botsense/bsNull.h"
#include "botsense/bsNullMsgs.h"

Go to the source code of this file.

Classes
struct	BsModCtlBlk_T
	Module resource control block structure type. More...

Macros
#define	BSMOD_MAX_HANDLES   BSPROXY_VCONN_MOD_NUMOF
	Maximum number of module supported simultaneous virtual connections.

Functions
static BsModCtlBlk_T *	bsModCtlBlkNew (int fd, bool_t bTrace)
	Allocate a new resource control block. More...
static void	bsModCtlBlkDelete (BsModCtlBlk_T *pCtlBlk)
	Delete an allocated resource control block. More...
static int	bsModNullReqWrite (BsVConnHnd_T hndVConn, BsTid_T uTid, BsMsgId_T uMsgIdReq, byte_t bufReq[], size_t uReqLen)
	Service a /dev/null write request. More...
int	bsModInit (const char *sModUri, const BsModProxyCb_T *pCallbacks)
	Initialize /dev/null module. More...
void	bsModExit ()
	Exit /dev/null module. More...
int	bsModOpen (BsVConnHnd_T hndVConn, bool_t bTrace, const char *sDevUri, byte_t argbuf[], size_t uArgSize)
	Open an /dev/null device and associate with the given handle. More...
int	bsModClose (BsVConnHnd_T hndVConn)
	Close the /dev/null device and disassociate virtual connection handle. More...
int	bsModRequest (BsVConnHnd_T hndVConn, BsTid_T uTid, BsMsgId_T uMsgIdReq, byte_t bufReq[], size_t uReqLen)
	Service an /dev/null request. More...
int	bsModTrace (BsVConnHnd_T hndVConn, bool_t bTrace)
	Enable/disable message tracing on handle. More...
const BsModInfo_T *	bsModInfo ()
	Query for the static module information. More...

Variables
static BsModInfo_T	BsModInfo
	Module static information. More...
static const char *	BsModUri
	module canonical name
static const BsModProxyCb_T *	BsModCallbacks
	module to bsProxy callbacks
static BsModRsrcTbl_T *	BsModRsrcTbl
	module resource table

Detailed Description

BotSense bsProxy server plug-in DLL /dev/null device module.

LastChangedDate

2010-09-13 10:25:05 -0600 (Mon, 13 Sep 2010)

Rev

581

Author

Robin Knight (robin.nosp@m..kni.nosp@m.ght@r.nosp@m.oadn.nosp@m.arrow.nosp@m.s.co.nosp@m.m)

Copyright

© 2010-2017. RoadNarrows LLC.
http://www.roadnarrows.com
All Rights Reserved

Definition in file bsNullServer.c.

Function Documentation

int bsModClose

(

BsVConnHnd_T

hndVConn

)

Close the /dev/null device and disassociate virtual connection handle.

The actual device and resources are only cleared if this is the last virtual connection reference to this device.

Parameters

hndVConn

Virtual connection handle.

Returns

On success, BS_OK is returned.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 397 of file bsNullServer.c.

References BS_ECODE_INTERNAL, BS_ECODE_NO_VCONN, BS_OK, BSMOD_LOG_ERROR, BSMOD_RSRC_IS_INUSE, BSMOD_TRY_VCONN_HND_RANGE, bsModCtlBlkDelete(), BsModProxyCb_T::m_cbModRsrcRemove, and BsModCtlBlk_T::m_fd.

{
  BsModCtlBlk_T  *pCtlBlk;

  // check if handle is in valid range
  BSMOD_TRY_VCONN_HND_RANGE(hndVConn);

  // check is resouce is in-use (i.e. opened)
  if( !BSMOD_RSRC_IS_INUSE(BsModRsrcTbl, hndVConn) )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_NO_VCONN,
        "Resources for virtual connection not found.");
    return -BS_ECODE_NO_VCONN;
  }

  // remove from module's resource table
  pCtlBlk = (BsModCtlBlk_T *)BsModCallbacks->m_cbModRsrcRemove(BsModRsrcTbl,
                                                               hndVConn);

  if( pCtlBlk == NULL )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_INTERNAL, "No module resource found.");
    return -BS_ECODE_INTERNAL;
  }

  if( pCtlBlk->m_fd >= 0 )
  {
    close(pCtlBlk->m_fd);
    LOGDIAG2("VConn=%d: close(fd=%d).", hndVConn, pCtlBlk->m_fd);
  }

  bsModCtlBlkDelete(pCtlBlk);

  return BS_OK;
}

static void bsModCtlBlkDelete ( BsModCtlBlk_T *  pCtlBlk )

static

Delete an allocated resource control block.

Parameters

pCtlBlk

Pointer to allocated control block.

Definition at line 142 of file bsNullServer.c.

Referenced by bsModClose(), and bsModExit().

{
  if( pCtlBlk != NULL )
  {
    delete(pCtlBlk);
  }
}

static BsModCtlBlk_T* bsModCtlBlkNew ( int  fd, bool_t  bTrace  )

static

Allocate a new resource control block.

Parameters

fd	File descriptor.
bTrace	Do [not] trace messages.

Returns

Pointer to new allocated control block.

Definition at line 125 of file bsNullServer.c.

References BsModCtlBlk_T::m_bTrace, and BsModCtlBlk_T::m_fd.

Referenced by bsModOpen().

{
  BsModCtlBlk_T *pCtlBlk;

  pCtlBlk = NEW(BsModCtlBlk_T);

  pCtlBlk->m_fd       = fd;
  pCtlBlk->m_bTrace   = bTrace;

  return pCtlBlk;
}

void bsModExit

(

)

Exit /dev/null module.

Called once prior to module being unloaded.

All open /dev/null devices will be closed.

Definition at line 288 of file bsNullServer.c.

References BSMOD_MAX_HANDLES, bsModCtlBlkDelete(), BsModUri, BsModProxyCb_T::m_cbModRsrcTblDelete, BsModCtlBlk_T::m_fd, and BsModRsrcTbl_T::m_vecRsrc.

{
  int             index;
  BsModCtlBlk_T  *pCtlBlk;

  // free all module virtual connnection resources.
  for(index=0; index<BSMOD_MAX_HANDLES; ++index)
  {
    if( (pCtlBlk = (BsModCtlBlk_T *)BsModRsrcTbl->m_vecRsrc[index]) != NULL )
    {
      if( pCtlBlk->m_fd >= 0 )
      {
        close(pCtlBlk->m_fd);
      }
      bsModCtlBlkDelete(pCtlBlk);
    }
  }

  // free resource table
  BsModCallbacks->m_cbModRsrcTblDelete(BsModRsrcTbl);

  delete((char *)BsModUri);
}

const BsModInfo_T* bsModInfo

(

)

Query for the static module information.

Returns

Pointer to module static information.

Definition at line 526 of file bsNullServer.c.

References BsModInfo.

{
  return &BsModInfo;
}

int bsModInit	(	const char *	sModUri,
		const BsModProxyCb_T *	pCallbacks
	)

Initialize /dev/null module.

Called once after module is loaded.

Parameters

sModUri	Expanded, canonical module path name.
pCallbacks	Pointer to a set of module -> bsProxy core callback functions.

Returns

On success, BS_OK is returned.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 268 of file bsNullServer.c.

References BS_OK, BSMOD_MAX_HANDLES, BsModUri, and BsModProxyCb_T::m_cbModRsrcTblNew.

{
  BsModUri = new_strdup(sModUri);

  // save bsProxy server callbacks
  BsModCallbacks = pCallbacks;

  // create module resource table
  BsModRsrcTbl = BsModCallbacks->m_cbModRsrcTblNew(BSMOD_MAX_HANDLES);

  return BS_OK;
}

static int bsModNullReqWrite ( BsVConnHnd_T  hndVConn, BsTid_T  uTid, BsMsgId_T  uMsgIdReq, byte_t  bufReq[], size_t  uReqLen  )

static

Service a /dev/null write request.

Note

A module-specific request service must send a response.

Parameters

hndVConn	Virtual connection handle.
uTid	Request-Response transaction id.
uMsgIdReq	Request message id.
bufReq	Packed request message buffer.
uReqLen	Size of request in buffer (number of bytes).

Returns

On success, BS_OK is returned.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 163 of file bsNullServer.c.

References BS_ECODE_BAD_MSG, BS_ECODE_BAD_VCONN_HND, BS_ECODE_NO_VCONN, BS_ECODE_SYS, BS_OK, BSMOD_IS_VCONN_HANDLE, BSMOD_RSRC, BSMOD_SEND_ERROR_RSP, BSMOD_SEND_NMERROR_RSP, BSMOD_SEND_SYSERROR_RSP, BsNullMsgIdRspWrite, BsNullPackRspWrite(), BsNullUnpackReqWrite(), BSPROXY_BUF_BODY, BSPROXY_MSG_MAX_LEN, BsModCtlBlk_T::m_bTrace, BsNullRspWrite_T::m_byteswritten, BsModProxyCb_T::m_cbSendRsp, BsNullReqWrite_T::m_count, BsModCtlBlk_T::m_fd, BsNullReqWrite_T::m_writebuf, and BsNullReqWrite_T::u.

Referenced by bsModRequest().

{
  static BsNullMsgId_T  uMsgIdRsp = BsNullMsgIdRspWrite;

  BsModCtlBlk_T    *pCtlBlk;                      // resource control block
  BsNullReqWrite_T   msgReq;                       // request message 
  BsNullRspWrite_T   msgRsp;                       // response message 
  byte_t            bufRsp[BSPROXY_MSG_MAX_LEN];  // req/rsp buffer
  int               n;                            // number of bytes/return code

  //
  // Parameter checks
  //
  if( !BSMOD_IS_VCONN_HANDLE(hndVConn) )
  {
    BSMOD_SEND_ERROR_RSP(BsModCallbacks, hndVConn, uTid, BS_ECODE_BAD_VCONN_HND,
          "Module vconn handle out-of-range.");
    return -BS_ECODE_BAD_VCONN_HND; \
  }

  // retrieve the resource control block
  pCtlBlk = (BsModCtlBlk_T *)BSMOD_RSRC(BsModRsrcTbl, hndVConn);

  if( pCtlBlk == NULL )
  {
    BSMOD_SEND_ERROR_RSP(BsModCallbacks, hndVConn, uTid, BS_ECODE_NO_VCONN,
        "No resources for virtual connection found.");
    return -BS_ECODE_NO_VCONN;
  }

  //
  // Unpack client request.
  //
  n = BsNullUnpackReqWrite(bufReq, uReqLen, &msgReq, pCtlBlk->m_bTrace);

  // check unpacking return code
  if( n < 0 )
  {
    BSMOD_SEND_NMERROR_RSP(BsModCallbacks, hndVConn, uTid, n,
        "MsgId=%u", uMsgIdReq);
    return -BS_ECODE_BAD_MSG;
  }

  //
  // Execute client request.
  //
  n = write(pCtlBlk->m_fd, msgReq.m_writebuf.u.m_buf,
                      (size_t)msgReq.m_writebuf.m_count);

  // check operation return code
  if( n < 0 )
  {
    BSMOD_SEND_SYSERROR_RSP(BsModCallbacks, hndVConn, uTid,
        "write(fd=%d, ...).", pCtlBlk->m_fd);
    return -BS_ECODE_SYS;
  }

  LOGDIAG3("VConn=%d: %d=write(fd=%d, buf=%p, count=%zu).",
      hndVConn, n, pCtlBlk->m_fd, msgReq.m_writebuf.u.m_buf,
      (size_t)msgReq.m_writebuf.m_count);

  //
  // Pack server response.
  //
  msgRsp.m_byteswritten = (byte_t)n;
    
  // pack
  n = BsNullPackRspWrite(&msgRsp, BSPROXY_BUF_BODY(bufRsp), pCtlBlk->m_bTrace);

  // check packing return code
  if( n < 0 )
  {
    BSMOD_SEND_NMERROR_RSP(BsModCallbacks, hndVConn, uTid, n,
        "MsgId=%u", uMsgIdRsp);
    return -BS_ECODE_BAD_MSG;
  }

  //
  // Send response.
  //
  BsModCallbacks->m_cbSendRsp(hndVConn, uTid, uMsgIdRsp, bufRsp, (size_t)n);

  return BS_OK;
}

int bsModOpen	(	BsVConnHnd_T	hndVConn,
		bool_t	bTrace,
		const char *	sDevUri,
		byte_t	argbuf[],
		size_t	uArgSize
	)

Open an /dev/null device and associate with the given handle.

Subsequent calls to the module use the given handle to associate the specific module-device instance.

The argument buffer contains packed message arguements specific to the device and module. For this /dev/null module, there are now additional arguments.

Note

It is the responsibile of the client to ensure consistency if more than one virtual connection is established.

Parameters

hndVConn	Virtual connection handle.
bTrace	Do [not] enable message tracing on this handle.
sDevUri	Device URI.
argbuf	Packed specific open configuration arguments submessage.
uArgSize	Size of packed argumets in buffer (number of bytes).

Returns

On success, returns a unique resource descriptor ≥ 0 which is typically an opened file descriptor or socket descriptor, but can be module defined.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 337 of file bsNullServer.c.

References BS_ECODE_BUSY, BS_ECODE_NO_RSRC, BS_ECODE_SYS, BSMOD_LOG_ERROR, BSMOD_LOG_SYSERROR, BSMOD_MAX_HANDLES, BSMOD_RSRC_INUSE_COUNT, BSMOD_RSRC_IS_INUSE, BSMOD_TRY_VCONN_HND_RANGE, bsModCtlBlkNew(), and BsModProxyCb_T::m_cbModRsrcAdd.

{
  BsModCtlBlk_T    *pCtlBlk;
  int               fd;

  // Check if handle is in valid range.
  BSMOD_TRY_VCONN_HND_RANGE(hndVConn);

  // Check if resources are available.
  if( BSMOD_RSRC_INUSE_COUNT(BsModRsrcTbl) >= BSMOD_MAX_HANDLES )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_NO_RSRC,
        "InUseCount=%u: No more resources available.",
        BSMOD_RSRC_INUSE_COUNT(BsModRsrcTbl));
    return -BS_ECODE_NO_RSRC;
  }
  
  // Check if the handle in this module's resource table is not already in-use.
  else if( BSMOD_RSRC_IS_INUSE(BsModRsrcTbl, hndVConn) )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_BUSY, 
        "Module virtual connection handle already in use");
    return -BS_ECODE_BUSY;
  }

  // open device
  fd = open(sDevUri, O_WRONLY);

  if( fd < 0 )
  {
    BSMOD_LOG_SYSERROR(hndVConn, "open(%s,...).", sDevUri);
    return -BS_ECODE_SYS;
  }

  // allocate a new control block and initialize
  pCtlBlk = bsModCtlBlkNew(fd, bTrace);

  // add to module resource table
  BsModCallbacks->m_cbModRsrcAdd(BsModRsrcTbl, hndVConn, pCtlBlk);

  LOGDIAG2("VConn=%d: %d=open(dev=%s, ...).", hndVConn, fd, sDevUri);

  return fd;
}

int bsModRequest	(	BsVConnHnd_T	hndVConn,
		BsTid_T	uTid,
		BsMsgId_T	uMsgIdReq,
		byte_t	bufReq[],
		size_t	uReqLen
	)

Service an /dev/null request.

Note

A module-specific request service must send a response.

Parameters

hndVConn	Virtual connection handle.
uTid	Request-Response transaction id.
uMsgIdReq	Request message id.
bufReq	Packed request message buffer.
uReqLen	Size of request in buffer (number of bytes).

Returns

On success, BS_OK is returned.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 446 of file bsNullServer.c.

References BS_ECODE_BAD_VCONN_HND, BS_ECODE_NO_VCONN, BS_ECODE_UNKNOWN_REQ, BSMOD_IS_VCONN_HANDLE, BSMOD_RSRC, BSMOD_SEND_ERROR_RSP, bsModNullReqWrite(), and BsNullMsgIdReqWrite.

{
  BsModCtlBlk_T  *pCtlBlk;

  // check if handle is in valid range
  if( !BSMOD_IS_VCONN_HANDLE(hndVConn) )
  {
    BSMOD_SEND_ERROR_RSP(BsModCallbacks, hndVConn, uTid, BS_ECODE_BAD_VCONN_HND,
          "Module vconn handle out-of-range.");
    return -BS_ECODE_BAD_VCONN_HND; \
  }

  // retrieve resource control block
  pCtlBlk = (BsModCtlBlk_T *)BSMOD_RSRC(BsModRsrcTbl, hndVConn);

  // check resource
  if( pCtlBlk == NULL )
  {
    BSMOD_SEND_ERROR_RSP(BsModCallbacks, hndVConn, uTid, BS_ECODE_NO_VCONN,
        "No resources for virtual connection found.");
    return -BS_ECODE_NO_VCONN;
  }

  switch( uMsgIdReq )
  {
    case BsNullMsgIdReqWrite:
      return bsModNullReqWrite(hndVConn, uTid, uMsgIdReq, bufReq, uReqLen);
    default:
      BSMOD_SEND_ERROR_RSP(BsModCallbacks, hndVConn, uTid, BS_ECODE_UNKNOWN_REQ,
          "MsgId=%u.", uMsgIdReq);
      return -BS_ECODE_UNKNOWN_REQ;
  }
}

int bsModTrace	(	BsVConnHnd_T	hndVConn,
		bool_t	bTrace
	)

Enable/disable message tracing on handle.

Parameters

hndVConn	Virtual connection handle.
bTrace	Do [not] enable message tracing on this handle.

Returns

On success, BS_OK is returned.
On error, the appropriate < 0 negated BotSense Error Code is returned.

Definition at line 492 of file bsNullServer.c.

References BS_ECODE_BAD_VCONN_HND, BS_ECODE_NO_VCONN, BS_OK, BSMOD_IS_VCONN_HANDLE, BSMOD_LOG_ERROR, BSMOD_RSRC, and BsModCtlBlk_T::m_bTrace.

{
  BsModCtlBlk_T  *pCtlBlk;

  // check if handle is in valid range
  if( !BSMOD_IS_VCONN_HANDLE(hndVConn) )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_BAD_VCONN_HND,
          "Module vconn handle out-of-range.");
    return -BS_ECODE_BAD_VCONN_HND;
  }

  // retrieve resource control block
  pCtlBlk = (BsModCtlBlk_T *)BSMOD_RSRC(BsModRsrcTbl, hndVConn);

  // check resource
  if( pCtlBlk == NULL )
  {
    BSMOD_LOG_ERROR(hndVConn, BS_ECODE_NO_VCONN,
        "No resources for virtual connection found.");
    return -BS_ECODE_NO_VCONN;
  }

  pCtlBlk->m_bTrace = bTrace;

  return BS_OK;
}

Variable Documentation

BsModInfo_T BsModInfo

static

Initial value:

= 
{
  .mod_name   = BS_NULL_SERVER_MOD,
  .brief      = "The /dev/null proxied device.",
  .version    = "1.0.0",
  .date       = "2010.07.21",
  .maintainer = "RaodNarrows LLC",
  .license    = "(C) 2010 RoadNarrows LLC. All rights reserved."
}

Module static information.

Definition at line 75 of file bsNullServer.c.

Referenced by bsModInfo().