From: Stephan Bosch <stephan.bosch@dovecot.fi>
Date: Thu, 13 Dec 2018 09:06:17 +0000 (+0100)
Subject: lib: Implement reliable sleep functions i_sleep*_usecs(), i_sleep*_msecs(), and i_sle... 
X-Git-Tag: 2.3.8~207
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e5c2788b0a19ac1b090b0925fb8125d8fe0f1235;p=thirdparty%2Fdovecot%2Fcore.git

lib: Implement reliable sleep functions i_sleep*_usecs(), i_sleep*_msecs(), and i_sleep*_secs().

Versions with and without support for being interrupted by signals are available.
---

diff --git a/src/lib/Makefile.am b/src/lib/Makefile.am
index 3226e3670a..ffed17f79b 100644
--- a/src/lib/Makefile.am
+++ b/src/lib/Makefile.am
@@ -145,6 +145,7 @@ liblib_la_SOURCES = \
 	sha1.c \
 	sha2.c \
 	sha3.c \
+	sleep.c \
 	sort.c \
 	stats-dist.c \
 	str.c \
@@ -299,6 +300,7 @@ headers = \
 	sha1.h \
 	sha2.h \
 	sha3.h \
+	sleep.h \
 	sort.h \
 	stats-dist.h \
 	str.h \
diff --git a/src/lib/sleep.c b/src/lib/sleep.c
new file mode 100644
index 0000000000..7b3b6fa911
--- /dev/null
+++ b/src/lib/sleep.c
@@ -0,0 +1,74 @@
+/* Copyright (c) 2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "sleep.h"
+
+#include <time.h>
+
+static bool ATTR_NOWARN_UNUSED_RESULT
+sleep_timespec(const struct timespec *ts_sleep, bool interruptible)
+{
+	struct timespec ts_remain = *ts_sleep;
+
+	while (nanosleep(&ts_remain, &ts_remain) < 0) {
+		if (errno != EINTR)
+			i_fatal("nanosleep(): %m");
+		if (interruptible)
+			return FALSE;
+	}
+	return TRUE;
+}
+
+void i_sleep_usecs(unsigned long long usecs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = (time_t)(usecs / 1000000);
+	ts_sleep.tv_nsec = (long)(usecs % 1000000) * 1000;
+	sleep_timespec(&ts_sleep, FALSE);
+}
+
+void i_sleep_msecs(unsigned int msecs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = (time_t)(msecs / 1000);
+	ts_sleep.tv_nsec = (long)(msecs % 1000) * 1000000;
+	sleep_timespec(&ts_sleep, FALSE);
+}
+
+void i_sleep_secs(time_t secs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = secs;
+	ts_sleep.tv_nsec = 0;
+	sleep_timespec(&ts_sleep, FALSE);
+}
+
+bool i_sleep_intr_usecs(unsigned long long usecs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = (time_t)(usecs / 1000000);
+	ts_sleep.tv_nsec = (long)(usecs % 1000000) * 1000;
+	return sleep_timespec(&ts_sleep, TRUE);
+}
+
+bool i_sleep_intr_msecs(unsigned int msecs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = (time_t)(msecs / 1000);
+	ts_sleep.tv_nsec = (long)(msecs % 1000) * 1000000;
+	return sleep_timespec(&ts_sleep, TRUE);
+}
+
+bool i_sleep_intr_secs(time_t secs)
+{
+	struct timespec ts_sleep;
+
+	ts_sleep.tv_sec = secs;
+	ts_sleep.tv_nsec = 0;
+	return sleep_timespec(&ts_sleep, TRUE);
+}
diff --git a/src/lib/sleep.h b/src/lib/sleep.h
new file mode 100644
index 0000000000..0f8d7c30ca
--- /dev/null
+++ b/src/lib/sleep.h
@@ -0,0 +1,30 @@
+#ifndef SLEEP_H
+#define SLEEP_H
+
+/* Sleep for the indicated number of microseconds. Signal interruptions are
+   handled and ignored internally. */
+void i_sleep_usecs(unsigned long long usecs);
+/* Sleep for the indicated number of milliseconds. Signal interruptions are
+   handled and ignored internally. */
+void i_sleep_msecs(unsigned int msecs);
+/* Sleep for the indicated number of seconds. Signal interruptions are
+   handled and ignored internally. */
+void i_sleep_secs(time_t secs);
+
+/* Sleep for the indicated number of microseconds while allowing signal
+   interruptions. This function returns FALSE when it is interrupted by a
+   signal. Otherwise, this function always returns TRUE. */
+bool ATTR_NOWARN_UNUSED_RESULT
+i_sleep_intr_usecs(unsigned long long usecs);
+/* Sleep for the indicated number of milliseconds while allowing signal
+   interruptions. This function returns FALSE when it is interrupted by a
+   signal. Otherwise, this function always returns TRUE. */
+bool ATTR_NOWARN_UNUSED_RESULT
+i_sleep_intr_msecs(unsigned int msecs);
+/* Sleep for the indicated number of seconds while allowing signal
+   interruptions. This function returns FALSE when it is interrupted by a
+   signal. Otherwise, this function always returns TRUE. */
+bool ATTR_NOWARN_UNUSED_RESULT
+i_sleep_intr_secs(time_t secs);
+
+#endif