From: Michal Bloch <m.bloch@samsung.com>
Date: Tue, 29 Jun 2021 18:17:54 +0000 (+0200)
Subject: Minor improvements to the udev polling loop.
X-Git-Tag: submit/tizen/20210705.023617~5
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=refs%2Fchanges%2F08%2F260608%2F2;p=platform%2Fcore%2Fapi%2Fperipheral-io.git

Minor improvements to the udev polling loop.

Change-Id: I068e2cbfe0243221f879961bb19ae8ea5e9b65f3
---

diff --git a/src/common.c b/src/common.c
index 969b39a..ed56e67 100644
--- a/src/common.c
+++ b/src/common.c
@@ -7,6 +7,7 @@
 #include <system_info.h>
 
 #define UDEV_MONITOR_POLL_TIMEOUT_MILISECONDS 100
+#define UDEV_MONITOR_POLL_ITERATIONS 10 //! How many times to poll? Affects the total timeout.
 
 int peripheral_lock(const char *file_name)
 {
@@ -95,13 +96,17 @@ int peripheral_wait_for_udev(struct udev_monitor *monitor, UdevCompareFunc func,
 	pfd.fd = udev_monitor_get_fd(monitor);
 	pfd.events = POLLIN;
 
-	for (int cnt = 0; cnt < 10; cnt++) {
-		_D("poll iteration");
-		if (poll(&pfd, 1, UDEV_MONITOR_POLL_TIMEOUT_MILISECONDS) < 0) {
-			_E("Failed to watch udev monitor");
+	for (int cnt = 0; cnt < UDEV_MONITOR_POLL_ITERATIONS; cnt++) {
+		_D("poll iteration %d", cnt);
+		int ready = poll(&pfd, 1, UDEV_MONITOR_POLL_TIMEOUT_MILISECONDS);
+		if (ready < 0) {
+			_E("Failed to watch udev monitor %m");
 			return -EIO;
 		}
 
+		if (ready == 0)
+			continue;
+
 		struct udev_device *dev = udev_monitor_receive_device(monitor);
 		if (dev) {
 			if (func(dev, func_data)) {