RTC usage bails out cleanly if accessing it goes wrong (e.g. HPET without generic...

diff --git a/NEWS b/NEWS
index 413185916bb265440384fd86fc6ecaf71500bc8f..f3cc5f214c09074adbf587ae99cd7e51f58f0377 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,11 @@
+New in version 1.21
+===================
+
+* Don't include Linux kernel header files any longer : allows chrony to compile
+  on recent distros.
+* Stop trying to use RTC if continuous streams of error messages would occur
+  (Linux with HPET).
+
 New in version 1.20
 ===================
 

diff --git a/chrony.texi b/chrony.texi
index 4642bb71ac90b8376355dcd44fb69a44ab6cc6ae..909a0cc355e1d850fddabb485ea9144d43a97cc7 100644 (file)
--- a/chrony.texi
+++ b/chrony.texi
@@ -836,7 +836,11 @@ compiled into the kernel).  An estimate is made of the RTC error at a
 particular RTC second, and the rate at which the RTC gains or loses time
 relative to true time.
 
-The RTC is fully supported in 2.2 and 2.4 kernels.
+The RTC is fully supported in 2.2, 2.4 and 2.6 kernels.
+
+On 2.6 kernels, if your motherboard has a HPET, you need to enable the
+@samp{HPET_EMULATE_RTC} option in your kernel configuration.  Otherwise, chrony
+will not be able to interact with the RTC device and will give up using it.
 
 For kernels in the 2.0 series prior to 2.0.32, the kernel was set up to
 trim the RTC every 11 minutes.  This would be disasterous for

diff --git a/rtc_linux.c b/rtc_linux.c
index 4b4ca1889acc360b1feb87799f4e78b640c2ae8a..8765a1299c83b91e6ff1a426df212fffc22d44f3 100644 (file)
--- a/rtc_linux.c
+++ b/rtc_linux.c
@@ -867,9 +867,19 @@ read_from_device(void *any)
 
   status = read(fd, &data, sizeof(data));
   if (status < 0) {
+    /* This looks like a bad error : the file descriptor was indicating it was
+     * ready to read but we couldn't read anything.  Give up. */
     LOG(LOGS_ERR, LOGF_RtcLinux, "Could not read flags %s : %s", CNF_GetRtcDevice(), strerror(errno));
     error = 1;
-    goto turn_off_interrupt;
+    SCH_RemoveInputFileHandler(fd);
+    switch_interrupts(0); /* Likely to raise error too, but just to be sure... */
+    close(fd);
+    fd = -1;
+    if (logfile) {
+      fclose(logfile);
+      logfile = NULL;
+    }
+    return;
   }    
 
   if ((data & RTC_UIE) == RTC_UIE) {