X-Git-Url: https://gerrit.o-ran-sc.org/r/gitweb?a=blobdiff_plain;f=src%2Frmr%2Fsi%2Fsrc%2Fsi95%2Fsiterm.c;h=ce4874882dfc562ab3c6385b7b1adc3f88dbd834;hb=fcea3951d44de0cc55d33c5e114487abe79d3406;hp=0b74ba0018a3a5dc70ed03866500fc5cf7b87830;hpb=ec88d3c0563eeb6ae5f73427edb0b3c4d7acf299;p=ric-plt%2Flib%2Frmr.git

diff --git a/src/rmr/si/src/si95/siterm.c b/src/rmr/si/src/si95/siterm.c
index 0b74ba0..ce48748 100644
--- a/src/rmr/si/src/si95/siterm.c
+++ b/src/rmr/si/src/si95/siterm.c
@@ -20,45 +20,90 @@
 
 /*
 **************************************************************************
-*  Mnemonic: SIterm
-*  Abstract: This routine will terminate a session based on the tp_blk
-*            that is passed into the routine. The transport session block
-*            is released and removed from the ginfo list. The session is
-*            terminated by issuing a t_unbind call (if the unbind flag is
-*            on in the tpptr block), and then issuing a t_close.
-*  Parms:    gptr - Pointer to the global information block
-*            tpptr - Pointer to tp block that defines the open fd.
-*  Returns:  Nothing.
-*  Date:     18 January 1995
-*  Author:   E. Scott Daniels
+*  Mnemonic:	SIterm
+*  Abstract:	Manage the transport provider block information relating to
+*				the need to terminate the session. The block is left in the
+*				list; it is unsafe to clean the lsit up outside of the SIwait
+*				thread.  When safe, the SIrm_tpb() function can be called to
+*				do the rest of the work that was originally done by SIterm.
+*
+*  Date:     	18 January 1995
+*  Author:		E. Scott Daniels
 *
 **************************************************************************
 */
-#include "sisetup.h"     //  get the setup stuff 
+#include "sisetup.h"     //  get the setup stuff
 #include "sitransport.h"
 
+
+/*
+	Abort the connection in such a way that there is no resulting time-wait state.
+	This should be used cautiously but is needed for situations like when the Linux
+	connect() system call manages to connect us to ourselves through the even number
+	port bug.
+
+	This needs a real file desc as there may not yet be a transport block when
+	the connection may need to be aborted. For this reason, the function name is
+	lower case indicating that user programmes are discouraged from using this
+	function directly.
+*/
+extern void siabort_conn( int fd ) {
+	struct linger	opt_val;		// value passed as option to set call
+
+	opt_val.l_onoff = 1;			// MUST set linger on with a zero len timeout
+	opt_val.l_linger = 0;
+
+	setsockopt( fd, SOL_SOCKET, SO_LINGER, &opt_val, sizeof( opt_val ) );		// disable linger to prevent time-wait
+	CLOSE( fd );			// close will now abort and not result in time-wait (do NOT use shutdown() first!)
+}
+
+/*
+	Close the FD and mark the transport block as unusable/closed.
+	Removal of the block from the list is safe only from the siwait
+	thread.  If the abort flag is set in the transport block, then the
+	connection is aborted (reset).
+*/
 extern void SIterm( struct ginfo_blk* gptr, struct tp_blk *tpptr ) {
 
 	if( tpptr != NULL ) {
 		if( tpptr->fd >= 0 ) {
-			CLOSE( tpptr->fd );    
+			if( tpptr->flags & TPF_ABORT ) {
+				siabort_conn( tpptr->fd );
+			} else {
+				CLOSE( tpptr->fd );
+			}
+
 			if( tpptr->fd < MAX_FDS ) {
 				gptr->tp_map[tpptr->fd] = NULL;		// drop reference
 			}
 		}
 
-		if( tpptr->prev != NULL ) {            //  remove from the list 
-			tpptr->prev->next = tpptr->next;    //  point previous at the next 
-		} else {
-			gptr->tplist = tpptr->next;        //  this was head, make next new head 
-		}
+		tpptr->fd = -1;								// prevent future sends etc.
+		tpptr->flags |= TPF_DELETE;					// signal block deletion needed when safe
+	}
+}
 
-		if( tpptr->next != NULL ) {
-			tpptr->next->prev = tpptr->prev;  //  point next one back behind this one 
+/*
+	It is safe to remove the block from the list; if it was in the list
+	in the first place.
+*/
+extern void SIrm_tpb( struct ginfo_blk *gptr, struct tp_blk *tpptr ) {
+
+	if( tpptr != NULL ) {
+		if( tpptr->prev != NULL || tpptr->next != NULL ) {	// in the list
+			if( tpptr->prev != NULL ) {            //  remove from the list
+				tpptr->prev->next = tpptr->next;    //  point previous at the next
+			} else {
+				gptr->tplist = tpptr->next;        //  this was head, make next new head
+			}
+
+			if( tpptr->next != NULL ) {
+				tpptr->next->prev = tpptr->prev;  //  point next one back behind this one
+			}
 		}
 
-		free( tpptr->addr );             //  release the address bufers 
+		free( tpptr->addr );             //  release the address bufers
 		free( tpptr->paddr );
-		free( tpptr );                   //  and release the block 
+		free( tpptr );                   //  and release the block
 	}
 }