cmdmon: add reset command

The reset command drops all measurements and switches the reference to
the unsynchronised state. This command can help chronyd with recovery
when the measurements are known to be no longer valid or accurate, e.g.
due to moving the computer to a different network, or resuming the
computer from a low-power state (which resets the system clock).

diff --git a/candm.h b/candm.h
index 2d6699787c16d6da67bfe0cf07df1a47259b55ab..e0d5140cf20d03bc4397f6407774744f027c1aac 100644 (file)
--- a/candm.h
+++ b/candm.h
@@ -103,7 +103,8 @@
 #define REQ_ONOFFLINE 63
 #define REQ_ADD_SOURCE 64
 #define REQ_NTP_SOURCE_NAME 65
-#define N_REQUEST_TYPES 66
+#define REQ_RESET 66
+#define N_REQUEST_TYPES 67
 
 /* Structure used to exchange timespecs independent of time_t size */
 typedef struct {

diff --git a/client.c b/client.c
index de08be23b77f8be4047765ee1e7ae6d66090c11b..6f0aad2d77f2192392bf29924318093641bab497 100644 (file)
--- a/client.c
+++ b/client.c
@@ -1269,6 +1269,7 @@ give_help(void)
     "cyclelogs\0Close and re-open log files\0"
     "dump\0Dump all measurements to save files\0"
     "rekey\0Re-read keys from key file\0"
+    "reset\0Drop all measurements\0"
     "shutdown\0Stop daemon\0"
     "\0\0"
     "Client commands:\0\0"
@@ -1315,7 +1316,7 @@ command_name_generator(const char *text, int state)
     "deny", "dns", "dump", "exit", "help", "keygen", "local", "makestep",
     "manual", "maxdelay", "maxdelaydevratio", "maxdelayratio", "maxpoll",
     "maxupdateskew", "minpoll", "minstratum", "ntpdata", "offline", "online", "onoffline",
-    "polltarget", "quit", "refresh", "rekey", "reselect", "reselectdist",
+    "polltarget", "quit", "refresh", "rekey", "reselect", "reselectdist", "reset",
     "retries", "rtcdata", "serverstats", "settime", "shutdown", "smoothing",
     "smoothtime", "sourcename", "sources", "sourcestats",
     "timeout", "tracking", "trimrtc", "waitsync", "writertc",
@@ -2835,6 +2836,14 @@ process_cmd_shutdown(CMD_Request *msg, char *line)
 
 /* ================================================== */
 
+static void
+process_cmd_reset(CMD_Request *msg, char *line)
+{
+  msg->command = htons(REQ_RESET);
+}
+
+/* ================================================== */
+
 static int
 process_cmd_waitsync(char *line)
 {
@@ -3129,6 +3138,8 @@ process_line(char *line)
     process_cmd_reselect(&tx_message, line);
   } else if (!strcmp(command, "reselectdist")) {
     do_normal_submit = process_cmd_reselectdist(&tx_message, line);
+  } else if (!strcmp(command, "reset")) {
+    process_cmd_reset(&tx_message, line);
   } else if (!strcmp(command, "retries")) {
     ret = process_cmd_retries(line);
     do_normal_submit = 0;

diff --git a/cmdmon.c b/cmdmon.c
index 7950e7abf7e8257f8a594618f0ed7d3f773d2ba3..908977effd76b90bcfbd67a677f247ad7e1e9b90 100644 (file)
--- a/cmdmon.c
+++ b/cmdmon.c
@@ -134,6 +134,7 @@ static const char permissions[] = {
   PERMIT_AUTH, /* ONOFFLINE */
   PERMIT_AUTH, /* ADD_SOURCE */
   PERMIT_OPEN, /* NTP_SOURCE_NAME */
+  PERMIT_AUTH, /* RESET */
 };
 
 /* ================================================== */
@@ -1218,6 +1219,18 @@ handle_ntp_source_name(CMD_Request *rx_message, CMD_Reply *tx_message)
             sizeof (tx_message->data.ntp_source_name.name));
 }
 
+/* ================================================== */
+
+static void
+handle_reset(CMD_Request *rx_message, CMD_Reply *tx_message)
+{
+  struct timespec cooked_now, now;
+
+  SRC_ResetSources();
+  SCH_GetLastEventTime(&cooked_now, NULL, &now);
+  LCL_NotifyExternalTimeStep(&now, &cooked_now, 0.0, 0.0);
+}
+
 /* ================================================== */
 /* Read a packet and process it */
 
@@ -1595,6 +1608,10 @@ read_from_cmd_socket(int sock_fd, int event, void *anything)
           handle_ntp_source_name(&rx_message, &tx_message);
           break;
 
+        case REQ_RESET:
+          handle_reset(&rx_message, &tx_message);
+          break;
+
         default:
           DEBUG_LOG("Unhandled command %d", rx_command);
           tx_message.status = htons(STT_FAILED);

diff --git a/doc/chronyc.adoc b/doc/chronyc.adoc
index 2a99a167e0abfa35e7995527972ef11854430a14..e97c66fd1bc8a337d835af09d88c1e172bcf58ba 100644 (file)
--- a/doc/chronyc.adoc
+++ b/doc/chronyc.adoc
@@ -1171,6 +1171,13 @@ running.
 The *rekey* command causes *chronyd* to re-read the key file specified in the
 configuration file by the <<chrony.conf.adoc#keyfile,*keyfile*>> directive.
 
+[[reset]]*reset*::
+The *reset* command causes *chronyd* to drop all measurements and switch to the
+unsynchronised state. This command can help *chronyd* with recovery when the
+measurements are known to be no longer valid or accurate, e.g. due to moving
+the computer to a different network, or resuming the computer from a low-power
+state (which resets the system clock).
+
 [[shutdown]]*shutdown*::
 The *shutdown* command causes *chronyd* to exit. This is equivalent to sending
 the process the SIGTERM signal.

diff --git a/pktlength.c b/pktlength.c
index 32b6f5a3b228373a0b31c378fadecbc7cb091583..911f725e5c2a009e761075980f44b25d8608b968 100644 (file)
--- a/pktlength.c
+++ b/pktlength.c
@@ -123,6 +123,7 @@ static const struct request_length request_lengths[] = {
   REQ_LENGTH_ENTRY(ntp_source, null),           /* ADD_SOURCE */
   REQ_LENGTH_ENTRY(ntp_source_name,
                    ntp_source_name),            /* NTP_SOURCE_NAME */
+  REQ_LENGTH_ENTRY(null, null),                 /* RESET */
 };
 
 static const uint16_t reply_lengths[] = {

diff --git a/sources.c b/sources.c
index b440d9d6c8eead9ebda4c824bfe76b240e6babb1..2db0299f3612166c423fd2ba32c7a7c4e4af4a3b 100644 (file)
--- a/sources.c
+++ b/sources.c
@@ -1252,6 +1252,17 @@ SRC_RemoveDumpFiles(void)
 
 /* ================================================== */
 
+void
+SRC_ResetSources(void)
+{
+  int i;
+
+  for (i = 0; i < n_sources; i++)
+    SRC_ResetInstance(sources[i]);
+}
+
+/* ================================================== */
+
 int
 SRC_IsSyncPeer(SRC_Instance inst)
 {

diff --git a/sources.h b/sources.h
index c160029ed4f94ac607b65b349d75f9dbb146ef2b..75f0f232c8f3fc46cf0b03618dfc78d1e3485198 100644 (file)
--- a/sources.h
+++ b/sources.h
@@ -114,6 +114,8 @@ extern void SRC_DumpSources(void);
 extern void SRC_ReloadSources(void);
 extern void SRC_RemoveDumpFiles(void);
 
+extern void SRC_ResetSources(void);
+
 extern int SRC_IsSyncPeer(SRC_Instance inst);
 extern int SRC_IsReachable(SRC_Instance inst);
 extern int SRC_ReadNumberOfSources(void);

diff --git a/test/simulation/110-chronyc b/test/simulation/110-chronyc
index bc6b23263204250997c040aa26caf6815b2d1792..e20cf3d50d04a92ddd6da09c50e674ca836b860e 100755 (executable)
--- a/test/simulation/110-chronyc
+++ b/test/simulation/110-chronyc
@@ -138,6 +138,7 @@ for chronyc_conf in \
        "rekey" \
        "reselect" \
        "reselectdist 1e-3" \
+       "reset" \
        "settime 16:30" \
        "settime 16:30:05" \
        "settime Nov 21, 2015 16:30:05" \