Added Buffered Console Capabilities

A key capability needed to support simulators running with background
    execution is the ability to have a Telnet connected console which isn’t
    continuously connected.  This feature is called a Buffered Telnet console.
    Absolutely nothing changes for someone not interested in using the feature.
    However, if someone is interested in the feature, the following SCP
    commands are available:

         sim> SET CONSOLE TELNET=port                  ! Unchanged
         sim> SET CONSOLE TELNET=BUFFERED{=buffersize} ! buffersize defaults to 32K
         sim> SET CONSOLE TELNET=UNBUFFERED            ! restores normal behavior
         sim> SET CONSOLE TELNET=NOBUFFERED            ! synonym for UNBUFFERED
         sim> SET CONSOLE TELNET=LOG=logdestination    ! enables logging of Telnet session traffic (potentially separate from destination specified by SET CONSOLE LOG=conlogdest)
         sim> SET CONSOLE TELNET=NOLOG                 ! turns off specific logging of Telnet session

         sim> SET CONSOLE TELNET=LOG=conlogdest                ! turns on logging all console traffic (unless the telnet session logging is also specified).

    The logdestinations for any of the logging/debugging commands can
    now be:
    LOG, DEBUG, STDOUT, STDERR or any file specification (caps are not
    required, but these names are reserved to indicate the current
    destination of the specified file handles (sim_log, sim_deb,
    stdout, stderr).

    When a Console Telnet session is Buffered, a simulator will start
    (via BOOT CPU or whatever is appropriate for a particular simulator)
    without needing to have an active telnet connection.  When a Telnet
    connection comes along for the telnet port, the contents of the saved
    buffer (which wraps on overflow) are presented on the telnet session
    as output before session traffic.  This allows the connecting telnet
    client to see what happened before he connected since the likely
    reason he might be connecting to the console of a background
    simulator is to troubleshoot unusual behavior.

    The current structure has the optional ability to log the Telnet
    session separately from the simulator output (i.e. ini file command
    execution) is potentially useful when you need to review what the
    simulator may have output which may be difficult to find in and
    amongst the possibly verbose Operating system console output.
    If someone doesn’t use “SET CONSOLE TELNET=LOG=logdestination”,
    then the original strategy of logging all output to the target
    specified by “SET CONSOLE LOG=logdestination” is preserved.  Looking
    at the isolated console output might be more interesting if/when
    control flow scp commands are ever implemented (ON,GOTO, RETURN, etc.)

sim_defs.h

@@ -23,6 +23,7 @@
    used in advertising or otherwise to promote the sale, use or other dealings
    in this Software without prior written authorization from Robert M Supnik.
 
+   18-Jan-11    MP      Added log file reference count support
    21-Jul-08    RMS     Removed inlining support
    28-May-08    RMS     Added inlining support
    28-Jun-07    RMS     Added IA64 VMS support (from Norm Lastovica)
@@ -484,6 +485,13 @@ struct sim_debtab {
 #define DEBUG_PRI(d,m)  (sim_deb && (d.dctrl & (m)))
 #define DEBUG_PRJ(d,m)  (sim_deb && (d->dctrl & (m)))
 
+/* File Reference */
+struct sim_fileref {
+    char                name[CBUFSIZE];                 /* file name */
+    FILE                *file;                          /* file handle */
+    int32               refcount;                       /* reference count */
+    };
+
 /* The following macros define structure contents */
 
 #define UDATA(act,fl,cap) NULL,act,NULL,NULL,NULL,0,0,(fl),(cap),0,0
@@ -520,6 +528,7 @@ typedef struct sim_mtab MTAB;
 typedef struct sim_schtab SCHTAB;
 typedef struct sim_brktab BRKTAB;
 typedef struct sim_debtab DEBTAB;
+typedef struct sim_fileref FILEREF;
 
 /* Function prototypes */