From 167b88f646380966920283f24e489e35bcaf0468 Mon Sep 17 00:00:00 2001
From: Lars Brinkhoff <lars@nocrew.org>
Date: Tue, 28 Feb 2017 13:41:18 +0100
Subject: [PATCH] SN - snoop terminal.

---
 README.md       |   1 +
 build/build.tcl |   4 ++
 src/sysen3/sn.1 | 166 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 171 insertions(+)
 create mode 100644 src/sysen3/sn.1

diff --git a/README.md b/README.md
index f6bd846f..d7f59f96 100644
--- a/README.md
+++ b/README.md
@@ -218,6 +218,7 @@ A list of [known ITS machines](doc/machines.md).
    - SALV, old file system tool for KA and KL.
    - SCANDL, TTY OUTPUT SPY.
    - SEND, REPLY, replacements for DDT :SEND.
+   - SN, snoop terminal.
    - SPELL, ESPELL spell checker.
    - SRCCOM, Compares/merges source files, compares binary files.
    - STINK, linker.
diff --git a/build/build.tcl b/build/build.tcl
index 655068a7..f1c79bae 100644
--- a/build/build.tcl
+++ b/build/build.tcl
@@ -1178,6 +1178,10 @@ expect ":KILL"
 respond "*" ":midas sys1;ts os_sysen2;os\r"
 expect ":KILL"
 
+# sn
+respond "*" ":midas sys2;ts sn_sysen3;sn\r"
+expect ":KILL"
+
 # ttyswp
 respond "*" ":midas sys;ts ttyswp_sysen3;ttyswp\r"
 expect ":KILL"
diff --git a/src/sysen3/sn.1 b/src/sysen3/sn.1
new file mode 100644
index 00000000..bc9e10d9
--- /dev/null
+++ b/src/sysen3/sn.1
@@ -0,0 +1,166 @@
+; -*- midas -*-
+
+title sn - snoop
+
+a=1
+b=2
+c=3
+ch=4
+
+ttyo=10
+ttyi=11
+
+	loc 42
+	jsr tsint
+
+beg:	.break 12,[..rjcl,,consol]	;43
+	move a,[440700,,consol]
+	setom c
+beg0:	ildb b,a			;46
+	jumpe b,beg1
+	cail b,"0
+	 caile b,"9
+	  jrst beg1
+	skipge c
+	 movei c,0
+	lsh c,3
+	addi c,-"0(b)
+	jrst beg0
+beg1:	jumpge c,beg2			;60
+	move c,[squoze 0,syscon]
+	.eval c,
+	 setom c
+	jumpge c,beg2
+	.value [ASCIZ /:KILL :NO SYSTEM CONSOLE?
/]
+beg2:	.open ttyo,[%tjmor+20+.uao,,'TTY]
+	 .value
+	.open ttyi,[.uii,,'TTY]
+	 .value
+	.suset [.smask,,[%piioc\%pityi]]
+	movsi a,-sqtlng
+beg3:	move b,sqtabl+1(a)		;74
+	.eval b,
+	 .value
+	hrrm b,sqtabl(a)
+	aos a
+	aobjn a,beg3
+	move a,[-77,,1]
+	.call corblk
+	 .value
+	move a,@toop
+	setom first
+lup:	jsr getch			;107
+	trze b,200
+	 jrst ctlp
+	.iot ttyo,b
+	jrst lup
+ctlp:	caige b,numctl			;114
+	 jrst @ctltab(b)
+	jrst lup
+
+ctltab:	tymov				;117
+	tymov1
+	tyeeof
+	tyeeol
+	tyedlf
+	tyemtf
+	tyemtn
+	tyecrl
+	tyeeo1
+	tyebs
+	tyelf
+	tyercr
+	tyeeo1
+	tyeeo1
+	tyefs
+	tymov1
+	tyeeo1
+numctl==.-ctltab
+
+tymov:	jsr getch			;140
+	movem b,oldv
+	jsr getch
+tymov1:					;143
+tymov2:	jsr getch			;143
+	came b,oldv
+	 .iot ttyo,[^J]
+	jsr getch
+	.iot ttyo,[^P]
+	.iot ttyo,["H]
+	addi b,10
+	.iot ttyo,b
+	jrst lup
+tyemtf:					;154
+tyemtn:					;154
+tyeeo1:					;154
+tyedlf:					;154
+tyeeof:					;154
+tyeeol:	jrst lup			;154
+tyefs:	.iot ttyo,[^P]
+	.iot ttyo,["F]
+	jrst lup
+tyecrl:	.iot ttyo,[^M]		;160
+tyelf:	.iot ttyo,[^J]		;161
+	jrst lup
+tyebs:	.iot ttyo,[^H]		;163
+	jrst lup
+tyercr:	.iot ttyo,[^M]		;165
+	jrst lup
+
+getch:	0				;167
+	camn a,@tobep
+	 sub a,tobl
+	aosn first
+	 jrst .+3
+	camn a,@toop
+	 .hang
+	ildb b,a
+	jrst @getch
+
+sqtabl:					;200
+toip:	3,,0				;200
+	squoze 0,toip
+toop:	3,,0				;202
+	squoze 0,toop
+tobep:	3,,0				;204
+	squoze 0,tobep
+tobl:	0,,0				;206
+	squoze 0,tobl
+sqtlng==<.-sqtabl>_-1
+
+corblk:	setz				;210
+	sixbit /corblk/
+	movei %cbred
+	movei %jself
+	a
+	setzi 400000
+
+tsint:	0				;216
+	0
+	exch a,tsint
+tsin1:	trze a,400			;221
+	jrst [aos tsint+1
+	      jrst intret]
+	trze a,1
+	jrst [movei ch,ttyi
+	      .ityic ch,
+	      jrst intret
+	      caie ch,32
+	       jrst valrt
+	      jrst intret]
+	.value [ASCIZ /:UNKNOWN INTERRUPT?
/]
+intret:	jumpn a,tsin1			;226
+	move a,tsint
+	.dismis tsint+1
+valrt:	.iot ttyi,ch			;231
+	caie ch,^L
+	jrst valrt1
+	.iot ttyo,[^P]
+	.iot ttyo,["C]
+valrt1:	.break 16,140000		;236
+
+consol:	0				;237
+first:	0				;240
+oldv:	0				;241
+
+end beg