diff options
| author | Benjamin Berg <bberg@redhat.com> | 2021-11-24 12:09:18 +0100 |
|---|---|---|
| committer | Benjamin Berg <benjamin@sipsolutions.net> | 2021-12-01 15:29:18 +0000 |
| commit | 05fd2c58cb9965b60e3b39de93e06abfb4f286da (patch) | |
| tree | cc5f7d88dffa604cc60abf3e9f486a6b26cc3bb1 | |
| parent | a033154b2eaae1cba6259fb414887a7865c8bb80 (diff) | |
context: Ensure mainloop is idle before enumeration completes
This ensures that we have processed all hotplug events before
considering enumeration to be complete. This is important due to USB
persist being turned off. At resume time, devices will disappear and
immediately re-appear. In this situatoin, enumerate could first see the
old state with a removed device resulting in it to not be discovered.
As a hotplug event is semingly emitted by the kernel immediately, we
can simply make sure to process this hotplug event before returning
from enumerate.
Closes: fprintd#119
| -rw-r--r-- | libfprint/fp-context.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/libfprint/fp-context.c b/libfprint/fp-context.c index d4bd000..1f32215 100644 --- a/libfprint/fp-context.c +++ b/libfprint/fp-context.c @@ -426,6 +426,7 @@ void fp_context_enumerate (FpContext *context) { FpContextPrivate *priv = fp_context_get_instance_private (context); + gboolean dispatched; gint i; g_return_if_fail (FP_IS_CONTEXT (context)); @@ -564,8 +565,19 @@ fp_context_enumerate (FpContext *context) } #endif - while (priv->pending_devices) - g_main_context_iteration (NULL, TRUE); + /* Iterate until 1. we have no pending devices, and 2. the mainloop is idle + * This takes care of processing hotplug events that happened during + * enumeration. + * This is important due to USB `persist` being turned off. At resume time, + * devices will disappear and immediately re-appear. In this situation, + * enumerate could first see the old state with a removed device resulting + * in it to not be discovered. + * As a hotplug event is seemingly emitted by the kernel immediately, we can + * simply make sure to process all events before returning from enumerate. + */ + dispatched = TRUE; + while (priv->pending_devices || dispatched) + dispatched = g_main_context_iteration (NULL, !!priv->pending_devices); } /** |