wasp: On-device crash reporting

If an application crashes let's report it on the device so it can be
distinguished from a hang (if nothing else it should mean we get better
bug reports).

micropython

@@ -1 +1 @@
-Subproject commit 2e5cb3eb32bcd4d72a328697db5442a9950969c0
+Subproject commit 7f8eda310df53a086ea55281bc9361ef386ec01a

wasp/apps/pager.py

@@ -0,0 +1,119 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later
+# Copyright (C) 2020 Daniel Thompson
+
+import wasp
+import icons
+
+import io
+import sys
+
+
+class PagerApp():
+    """Show long text in a pager.
+
+    This is used to present text based information to the user. It is primarily
+    intended for notifications but is also used to provide debugging
+    information when applications crash.
+    """
+    NAME = 'Pager'
+    ICON = icons.app
+
+    def __init__(self, msg):
+        self._msg = msg
+        self._scroll = wasp.widgets.ScrollIndicator()
+
+    def foreground(self):
+        """Activate the application."""
+        self._page = 0
+        self._chunks = wasp.watch.drawable.wrap(self._msg, 240)
+        self._numpages = (len(self._chunks) - 2) // 9
+        wasp.system.request_event(wasp.EventMask.SWIPE_UPDOWN)
+        self._draw()
+
+    def background(self):
+        del self._chunks
+        del self._numpages
+
+    def swipe(self, event):
+        mute = wasp.watch.display.mute
+
+        if event[0] == wasp.EventType.UP:
+            if self._page >= self._numpages:
+                wasp.system.navigate(wasp.EventType.BACK)
+                return
+            self._page += 1
+        else:
+            if self._page <= 0:
+                wasp.watch.vibrator.pulse()
+                return
+            self._page -= 1
+        mute(True)
+        self._draw()
+        mute(False)
+
+    def _draw(self):
+        """Draw the display from scratch."""
+        draw = wasp.watch.drawable
+        draw.fill()
+
+        page = self._page
+        i = page * 9
+        j = i + 11
+        chunks = self._chunks[i:j]
+        for i in range(len(chunks)-1):
+            sub = self._msg[chunks[i]:chunks[i+1]].rstrip()
+            draw.string(sub, 0, 24*i)
+
+        scroll = self._scroll
+        scroll.up = page > 0
+        scroll.down = page < self._numpages
+        scroll.draw()
+
+class CrashApp():
+    """Crash handler application.
+
+    This application is launched automatically whenever another
+    application crashes. Our main job it to indicate as loudly as
+    possible that the system is no longer running correctly. This
+    app deliberately enables inverted video mode in order to deliver
+    that message as strongly as possible.
+    """
+    def __init__(self, exc):
+        """Capture the exception information.
+
+        This app does not actually display the exception information
+        but we need to capture the exception info before we leave
+        the except block.
+        """
+        msg = io.StringIO()
+        sys.print_exception(exc, msg)
+        self._msg = msg.getvalue()
+        msg.close()
+
+    def foreground(self):
+        """Indicate the system has crashed by drawing a couple of bomb icons.
+
+        If you owned an Atari ST back in the mid-eighties then I hope you
+        recognise this as a tribute a long forgotten home computer!
+        """
+        wasp.watch.display.invert(False)
+        draw = wasp.watch.drawable
+        draw.blit(icons.bomb, 0, 104)
+        draw.blit(icons.bomb, 32, 104)
+
+        wasp.system.request_event(wasp.EventMask.SWIPE_UPDOWN |
+                                  wasp.EventMask.SWIPE_LEFTRIGHT)
+
+    def background(self):
+        """Restore a normal display mode.
+
+        Conceal the display before the transition otherwise the inverted
+        bombs get noticed by the user.
+        """
+        wasp.watch.display.mute(True)
+        wasp.watch.display.invert(True)
+
+    def swipe(self, event):
+        """Show the exception message in a pager.
+        """
+        wasp.system.switch(PagerApp(self._msg))

wasp/apps/testapp.py

@@ -12,7 +12,7 @@ class TestApp():
     ICON = icons.app
 
     def __init__(self):
-        self.tests = ('Touch', 'String', 'Button', 'Crash', 'RLE')
+        self.tests = ('Touch', 'String', 'Wrap', 'Button', 'Crash', 'RLE')
         self.test = self.tests[0]
         self.scroll = wasp.widgets.ScrollIndicator()
 
@@ -56,6 +56,8 @@ class TestApp():
                     event[1], event[2]), 0, 108, width=240)
         elif self.test == 'String':
             self.benchmark_string()
+        elif self.test == 'Wrap':
+            self.benchmark_wrap()
         elif self.test == 'RLE':
             self.benchmark_rle()
 
@@ -88,6 +90,24 @@ class TestApp():
         del t
         draw.string('{}s'.format(elapsed / 1000000), 12, 24+192)
 
+    def benchmark_wrap(self):
+        draw = wasp.watch.drawable
+        draw.fill(0, 0, 30, 240, 240-30)
+        self.scroll.draw()
+        t = machine.Timer(id=1, period=8000000)
+        t.start()
+        draw = wasp.watch.drawable
+        s = 'This\nis a very long string that will need to be wrappedinmultipledifferentways!'
+        chunks = draw.wrap(s, 240)
+
+        for i in range(len(chunks)-1):
+            sub = s[chunks[i]:chunks[i+1]].rstrip()
+            draw.string(sub, 0, 48+24*i)
+        elapsed = t.time()
+        t.stop()
+        del t
+        draw.string('{}s'.format(elapsed / 1000000), 12, 24+192)
+
     def draw(self):
         """Redraw the display from scratch."""
         wasp.watch.display.mute(True)

wasp/boards/pinetime/manifest.py

@@ -7,6 +7,7 @@ freeze('../..',
         'apps/clock.py',
         'apps/flashlight.py',
         'apps/launcher.py',
+        'apps/pager.py',
         'apps/settings.py',
         'apps/testapp.py',
         'boot.py',

wasp/boards/simulator/watch.py

@@ -6,6 +6,12 @@ def sleep_ms(ms):
     time.sleep(ms / 1000)
 time.sleep_ms = sleep_ms
 
+import sys, traceback
+def print_exception(exc, file=sys.stdout):
+    exc_type, exc_value, exc_traceback = sys.exc_info()
+    traceback.print_exception(exc_type, exc_value, exc_traceback, file=file)
+sys.print_exception = print_exception
+
 import draw565
 
 from machine import I2C

wasp/draw565.py

@@ -235,3 +235,32 @@ class Draw565(object):
 
         if width:
             display.fill(0, x, y, rightpad, h)
+
+    def wrap(self, s, width):
+        font = self._font
+        max = len(s)
+        chunks = [ 0, ]
+        end = 0
+
+        while end < max:
+            start = end
+            l = 0
+
+            for i in range(start, max+1):
+                if i >= len(s):
+                    break
+                ch = s[i]
+                if ch == '\n':
+                    end = i+1
+                    break
+                if ch == ' ':
+                    end = i+1
+                (_, h, w) = font.get_ch(ch)
+                l += w + 1
+                if l > width:
+                    break
+            if end <= start:
+                end = i
+            chunks.append(end)
+
+        return chunks

wasp/icons.py

@@ -4,6 +4,19 @@
 # 1-bit RLE, generated from res/battery.png, 189 bytes
 battery = (36, 48, b'\x97\x0e\x14\x12\x11\x14\x10\x14\x0c\x08\x0c\x08\x08\x08\x0c\x08\x08\x08\x0c\x08\x08\x08\x0c\x08\x08\x04\x14\x04\x08\x04\x14\x04\x08\x04\x0c\x04\x04\x04\x08\x04\x0b\x05\x04\x04\x08\x04\n\x06\x04\x04\x08\x04\t\x07\x04\x04\x08\x04\x08\x07\x05\x04\x08\x04\x07\x07\x06\x04\x08\x04\x06\x07\x07\x04\x08\x04\x05\x07\x08\x04\x08\x04\x04\x0e\x02\x04\x08\x04\x03\x0f\x02\x04\x08\x04\x02\x10\x02\x04\x08\x04\x02\x10\x02\x04\x08\x04\x02\x0f\x03\x04\x08\x04\x02\x0e\x04\x04\x08\x04\x08\x07\x05\x04\x08\x04\x07\x07\x06\x04\x08\x04\x06\x07\x07\x04\x08\x04\x05\x07\x08\x04\x08\x04\x04\x07\t\x04\x08\x04\x04\x06\n\x04\x08\x04\x04\x05\x0b\x04\x08\x04\x04\x04\x0c\x04\x08\x04\x14\x04\x08\x04\x14\x04\x08\x04\x14\x04\x08\x04\x14\x04\x08\x1c\x08\x1c\x08\x1c\x08\x1c\x98')
 
+# 2-bit RLE, generated from res/bomb.png, 100 bytes
+bomb = (
+    b'\x02'
+    b'  '
+    b'\x15\xc2\x06\xc22\xc3\x03\xc2\x02\xc2\x13\xc1\x03\xc1\x1a\xc1'
+    b'\x05\xc5\x15\xc1\x1c\xc7\x04\xc2\x02\xc2\x0f\xc7\x19\xc7\x02\xc2'
+    b'\x06\xc2\r\xc7\x17\xcb\x13\xcf\x10\xc6\x02\xc9\x0e\xd3\r\xd3'
+    b'\x0c\xc5\x02\xce\x0b\xc4\x02\xcf\x0b\xd5\n\xc4\x01\xd2\t\xc3'
+    b'\x02\xd2\t\xc3\x01\xd3\t\xc3\x02\xd2\t\xc4\x01\xd2\n\xd5'
+    b'\x0b\xd5\x0b\xd5\x0c\xd3\r\xd3\x0e\xd1\x10\xcf\x13\xcb\x18\xc5'
+    b'\x0e'
+)
+
 # 2-bit RLE, generated from res/app_icon.png, 460 bytes
 app = (
     b'\x02'
@@ -98,6 +111,7 @@ settings = (
     b'C,t-r/p2l?X\x80m\xa6;\xa4'
     b'<\xa4<\xa4\x1e'
 )
+
 # 2-bit RLE, generated from res/torch_icon.png, 247 bytes
 torch = (
     b'\x02'
@@ -125,4 +139,3 @@ up_arrow = (16, 9, b'\x07\x02\r\x04\x0b\x06\t\x08\x07\n\x05\x0c\x03\x0e\x01 ')
 
 # 1-bit RLE, generated from res/down_arrow.png, 17 bytes
 down_arrow = (16, 9, b'\x00 \x01\x0e\x03\x0c\x05\n\x07\x08\t\x06\x0b\x04\r\x02\x07')
-

wasp/wasp.py

@@ -16,6 +16,7 @@ import widgets
 from apps.clock import ClockApp
 from apps.flashlight import FlashlightApp
 from apps.launcher import LauncherApp
+from apps.pager import CrashApp
 from apps.settings import SettingsApp
 from apps.testapp import TestApp
 
@@ -32,6 +33,7 @@ class EventType():
     TOUCH = 5
 
     HOME = 256
+    BACK = 257
 
 class EventMask():
     """Enumerated event masks.
@@ -179,7 +181,7 @@ class Manager():
                 self.switch(app_list[0])
             else:
                 watch.vibrator.pulse()
-        elif direction == EventType.HOME:
+        elif direction == EventType.HOME or direction == EventType.BACK:
             if self.app != app_list[0]:
                 self.switch(app_list[0])
             else:
@@ -298,7 +300,7 @@ class Manager():
             if 1 == self._button.get_event() or self.charging != charging:
                 self.wake()
 
-    def run(self):
+    def run(self, no_except=True):
         """Run the system manager synchronously.
 
         This allows all watch management activities to handle in the
@@ -312,8 +314,21 @@ class Manager():
         # been set running again.
         print('Watch is running, use Ctrl-C to stop')
 
+        if not no_except:
+            # This is a simplified (uncommented) version of the loop
+            # below
+            while True:
+                self._tick()
+                machine.deepsleep()
+
         while True:
-            self._tick()
+            try:
+                self._tick()
+            except KeyboardInterrupt:
+                raise
+            except Exception as e:
+                self.switch(CrashApp(e))
+
             # Currently there is no code to control how fast the system
             # ticks. In other words this code will break if we improve the
             # power management... we are currently relying on no being able