Set stdin back to blocking state on exit.
Change-Id: Ic15e9858aa43a8a85781328234c4ac80396eed12
diff --git a/edgetpuvision/gstreamer.py b/edgetpuvision/gstreamer.py
index 64adcba..7b18837 100644
--- a/edgetpuvision/gstreamer.py
+++ b/edgetpuvision/gstreamer.py
@@ -46,9 +46,13 @@
def __str__(self):
return self.value
-def set_nonblocking(fd):
- flags = fcntl.fcntl(fd, fcntl.F_GETFL)
- return fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
+@contextlib.contextmanager
+def nonblocking(fd):
+ os.set_blocking(fd, False)
+ try:
+ yield
+ finally:
+ os.set_blocking(fd, True)
@contextlib.contextmanager
def term_raw_mode(fd):
@@ -61,11 +65,28 @@
finally:
termios.tcsetattr(fd, termios.TCSAFLUSH, old)
-def get_nowait(q):
- try:
- return q.get_nowait()
- except queue.Empty:
- return None
+@contextlib.contextmanager
+def Commands():
+ commands = queue.Queue()
+
+ def on_keypress(fd, flags):
+ for ch in sys.stdin.read():
+ commands.put(ch)
+ return True
+
+ def get_nowait():
+ try:
+ return commands.get_nowait()
+ except queue.Empty:
+ return None
+
+ if sys.stdin.isatty():
+ fd = sys.stdin.fileno()
+ GLib.io_add_watch(fd, GLib.IO_IN, on_keypress)
+ with term_raw_mode(fd), nonblocking(fd):
+ yield get_nowait
+ else:
+ yield lambda: None
@contextlib.contextmanager
def Worker(process, maxsize=0):
@@ -151,17 +172,12 @@
sys.stderr.write('Error: %s: %s\n' % (err, debug))
Gtk.main_quit()
-def on_keypress(fd, flags, commands):
- for ch in sys.stdin.read():
- commands.put(ch)
- return True
-
-def on_new_sample(sink, pipeline, render_overlay, layout, images, commands):
+def on_new_sample(sink, pipeline, render_overlay, layout, images, get_command):
with pull_sample(sink) as (sample, data):
custom_command = None
save_frame = False
- command = get_nowait(commands)
+ command = get_command()
if command == COMMAND_SAVE_FRAME:
save_frame = True
elif command == COMMAND_PRINT_INFO:
@@ -241,7 +257,6 @@
def run_pipeline(pipeline, layout, render_overlay, display, signals=None):
signals = signals or {}
- commands = queue.Queue()
# Create pipeline
pipeline = describe(pipeline)
@@ -281,20 +296,13 @@
window.connect('delete-event', Gtk.main_quit)
window.show_all()
- with contextlib.ExitStack() as stack:
- images = stack.enter_context(Worker(save_frame))
-
- if sys.stdin.isatty():
- set_nonblocking(sys.stdin.fileno())
- GLib.io_add_watch(sys.stdin.fileno(), GLib.IO_IN, on_keypress, commands)
- stack.enter_context(term_raw_mode(sys.stdin.fileno()))
-
+ with Worker(save_frame) as images, Commands() as get_command:
signals = {'appsink':
{'new-sample': functools.partial(on_new_sample,
render_overlay=functools.partial(render_overlay, layout=layout),
layout=layout,
images=images,
- commands=commands)},
+ get_command=get_command)},
**signals
}
