From f404fdb46b2f50b82566c3e86e27559051d22a60 Mon Sep 17 00:00:00 2001
From: Ross Wilson <rzzzwilson@gmail.com>
Date: Sat, 11 Jul 2015 18:41:37 +0700
Subject: [PATCH] Problems with state of TTYIN device

---
 pymlac/TtyIn.py      | 51 ++++++++++++++++++++++++++------------------
 pymlac/test_TTYIN.py |  4 ++++
 2 files changed, 34 insertions(+), 21 deletions(-)

diff --git a/pymlac/TtyIn.py b/pymlac/TtyIn.py
index fa06df9..8eb26a6 100644
--- a/pymlac/TtyIn.py
+++ b/pymlac/TtyIn.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python 
+#!/usr/bin/python
 
 """
 Emulate the Input TTY device (TTYIN).
@@ -7,7 +7,7 @@ Emulate the Input TTY device (TTYIN).
 from Globals import *
 
 import log
-log = log.Log('test_CPU.log', log.Log.DEBUG)
+log = log.Log('test_TTYIN.log', log.Log.DEBUG)
 
 
 class TtyIn(object):
@@ -17,11 +17,11 @@ class TtyIn(object):
     DEVICE_READY = 1
     TTYIN_CHARS_PER_SECOND = 1000
     DEVICE_READY_CYCLES = int(CYCLES_PER_SECOND / TTYIN_CHARS_PER_SECOND)
-    
-    
+
+
     def __init__(self):
         """Initialize the TTYIN device."""
-    
+
         log('TTYIN: Initializing device')
 
         self.filename = None
@@ -32,22 +32,29 @@ class TtyIn(object):
         self.status = self.DEVICE_NOT_READY
 
         log('TTYIN: DEVICE_READY_CYCLES=%d' % self.DEVICE_READY_CYCLES)
-    
+
     def mount(self, fname):
         """Mount a file on the TTYIN device."""
-    
+
         log('TTYIN: Mounting file %s on device' % fname)
 
         self.filename = fname
         self.open_file = open(fname, 'r')
-        self.value = 0
+        self.value = self.open_file.read(1)
         self.atEOF = False
         self.cycle_count = self.DEVICE_READY_CYCLES
         self.status = self.DEVICE_NOT_READY
-    
+        if len(self.value) < 1:
+            # EOF on input file
+            self.atEOF = True
+            self.cycle_count = 0
+            self.value = 0
+            log('TTYIN: EOF set on device (file %s)' % self.fname)
+        self.value = ord(self.value)
+
     def dismount(self):
         """Dismount the file on the TTYIN device."""
-    
+
         log('TTYIN: Dismounting file %s' % self.filename)
 
         if self.open_file:
@@ -57,43 +64,45 @@ class TtyIn(object):
         self.value = 0
         self.atEOF = True
         self.status = self.DEVICE_NOT_READY
-    
+
     def read(self):
         """Return the current device value."""
 
         log('TTYIN: Reading device, value is %03o' % self.value)
 
         return self.value
-    
+
     def ready(self):
         """Return device status."""
 
         log("TTYIN: Device 'ready' status is %s" % str(self.status == self.DEVICE_READY))
 
         return (self.status == self.DEVICE_READY)
-    
+
     def clear(self):
         """Clear the device 'ready' status."""
-    
+
         log("TTYIN: Clearing device 'ready' status")
 
         self.status = self.DEVICE_NOT_READY
-    
+
     def tick(self, cycles):
         """Advance the device state by 'cycles' number of CPU cycles."""
-    
-        log("TTYIN: Doing 'tick' with %d cycles, .atEOF is %s" % (cycles, str(self.atEOF)))
 
-        if (not self.atEOF):
-            log('TTYIN: .cycle_count=%d' % self.cycle_count)
+        if not self.atEOF:
+            log("TTYIN: Doing 'tick' with %d cycles, .atEOF is %s, .cycle_count=%d"
+                    % (cycles, str(self.atEOF), self.cycle_count))
             self.cycle_count -= cycles
             if self.cycle_count <= 0:
-                self.cycle_count = self.DEVICE_READY_CYCLES
+                log('TTYIN: .cycle_count expired, read new character')
+                self.cycle_count += self.DEVICE_READY_CYCLES
                 self.value = self.open_file.read(1)
                 self.status = self.DEVICE_READY
                 if len(self.value) < 1:
                     # EOF on input file
                     self.atEOF = True
-                    self.value = 0
+                    self.value = chr(0)
                     self.cycle_count = 0
+                    self.status = self.DEVICE_NOT_READY
+                    log('TTYIN: EOF set on device (file %s)' % self.filename)
                 self.value = ord(self.value)
diff --git a/pymlac/test_TTYIN.py b/pymlac/test_TTYIN.py
index 04a377f..0dbce55 100644
--- a/pymlac/test_TTYIN.py
+++ b/pymlac/test_TTYIN.py
@@ -31,6 +31,8 @@ def error(msg):
 def create_tty_file(filename):
     """Create a TTY file."""
     
+    print('create_tty_file(%s)' % filename)
+
     # create a test file
     with open(filename, 'wb') as fd:
         # leader
@@ -66,6 +68,8 @@ def mount_dismount(filename):
 def read_tty(filename):
     """Mount a file and read from it."""
 
+    print('read_tty(%s)' % filename)
+
     ttyin = TtyIn.TtyIn()
     ttyin.mount(filename)