[PATCH] knotty: add OSC 9;4 sequence for progress display

[git@cookiesoft.de]

From: Marcel Hellwig <git@cookiesoft.de>

OSC 9;4[0] allows the terminal emulator to display a progress bar.
This is helpful for the long-running tasks in both Bitbake and Devtool.

The most prominent supporters are Windows Terminal and KDE's Konsole.
Terminals that do not support the sequence simply ignore it, so no
special treament is required.

[0]: https://learn.microsoft.com/en-us/windows/terminal/tutorials/progress-bar-sequences

Signed-off-by: Marcel Hellwig <git@cookiesoft.de>
---
 bitbake/lib/bb/ui/knotty.py | 58 +++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/bitbake/lib/bb/ui/knotty.py b/bitbake/lib/bb/ui/knotty.py
index 5198e93d8d..b7388f2948 100644
--- a/bitbake/lib/bb/ui/knotty.py
+++ b/bitbake/lib/bb/ui/knotty.py
@@ -119,6 +119,58 @@ class InteractConsoleLogFilter(logging.Filter):
         self.tf.clearFooter()
         return True
 
+class Osc94FilterNotifier(logging.Filter):
+    def __init__(self, tf):
+        self.tf = tf
+
+    def filter(self, record):
+        if record.levelno == bb.msg.BBLogFormatter.ERROR:
+            self.tf.osc94.error()
+        elif record.levelno == bb.msg.BBLogFormatter.WARNING:
+            self.tf.osc94.warning()
+
+        return True
+
+class Osc94(object):
+    REMOVE = 0
+    SET = 1
+    ERROR = 2
+    INDETERMINATE = 3
+    WARNING = 4
+
+    def __init__(self, fd = None):
+        self.fd = fd
+        self._warning = False
+        self._error = False
+
+    def _write(self, what, argument = None):
+        if self.fd is not None:
+            argument = "" if argument is None else argument
+            self.fd.write(f"\x1b]9;4;{what};{argument}\x07")
+            self.fd.flush()
+
+    def clear(self):
+        self._write(self.REMOVE)
+
+    def indeterminate(self):
+        self._write(self.INDETERMINATE)
+
+    def error(self):
+        self._error = True
+
+    def warning(self):
+        self._warning = True
+
+    def progress(self, value):
+        value = int(min(max(value, 0), 100))
+        if self._error:
+            self._write(self.ERROR, value)
+        elif self._warning:
+            self._write(self.WARNING, value)
+        else:
+            self._write(self.SET, value)
+
+
 class TerminalFilter(object):
     rows = 25
     columns = 80
@@ -160,6 +212,7 @@ class TerminalFilter(object):
         self.lastpids = []
         self.lasttime = None
         self.quiet = quiet
+        self.osc94 = Osc94(sys.stdout)
 
         if not self.interactive:
             return
@@ -203,8 +256,10 @@ class TerminalFilter(object):
 
         for h in handlers:
             h.addFilter(InteractConsoleLogFilter(self))
+            h.addFilter(Osc94FilterNotifier(self))
 
         self.main_progress = None
+        self.osc94.indeterminate()
 
     def clearFooter(self):
         if self.footer_present:
@@ -274,6 +329,7 @@ class TerminalFilter(object):
                 tasks.append(msg)
 
         if self.main.shutdown:
+            self.osc94.indeterminate()
             content = pluralise("Waiting for %s running task to finish",
                                 "Waiting for %s running tasks to finish", len(activetasks))
             if not self.quiet:
@@ -303,6 +359,7 @@ class TerminalFilter(object):
             self.main_progress.setmessage(msg)
             progress = max(0, self.helper.tasknumber_current - 1)
             content += self.main_progress.update(progress)
+            self.osc94.progress(self.main_progress.percent)
             print('')
         lines = self.getlines(content)
         if not self.quiet:
@@ -335,6 +392,7 @@ class TerminalFilter(object):
         return lines
 
     def finish(self):
+        self.osc94.clear()
         if self.stdinbackup:
             fd = sys.stdin.fileno()
             self.termios.tcsetattr(fd, self.termios.TCSADRAIN, self.stdinbackup)
-- 
2.53.0