Adding upstream version 4.0.upstream/4.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 176 insertions, 0 deletions

diff --git a/tempcomp.c b/tempcomp.c
new file mode 100644
index 0000000..a468e33
--- /dev/null
+++ b/tempcomp.c
@@ -0,0 +1,176 @@
+/*
+  chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Miroslav Lichvar  2011, 2014
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ * 
+ **********************************************************************
+
+  =======================================================================
+
+  Routines implementing temperature compensation.
+
+  */
+
+#include "config.h"
+
+#include "array.h"
+#include "conf.h"
+#include "local.h"
+#include "memory.h"
+#include "util.h"
+#include "logging.h"
+#include "sched.h"
+#include "tempcomp.h"
+
+/* Sanity limit (in ppm) */
+#define MAX_COMP 10.0
+
+static SCH_TimeoutID timeout_id;
+
+static LOG_FileID logfileid;
+
+static char *filename;
+static double update_interval;
+static double T0, k0, k1, k2;
+
+struct Point {
+  double temp;
+  double comp;
+};
+
+static ARR_Instance points;
+
+static double
+get_tempcomp(double temp)
+{
+  unsigned int i;
+  struct Point *p1 = NULL, *p2 = NULL;
+
+  /* If not configured with points, calculate the compensation from the
+     specified quadratic function */
+  if (!points)
+    return k0 + (temp - T0) * k1 + (temp - T0) * (temp - T0) * k2;
+
+  /* Otherwise interpolate/extrapolate between two nearest points */
+
+  for (i = 1; i < ARR_GetSize(points); i++) {
+    p2 = (struct Point *)ARR_GetElement(points, i);
+    if (p2->temp >= temp)
+      break;
+  }
+  p1 = p2 - 1;
+
+  return (temp - p1->temp) / (p2->temp - p1->temp) *
+         (p2->comp - p1->comp) + p1->comp;
+}
+
+static void
+read_timeout(void *arg)
+{
+  FILE *f;
+  double temp, comp;
+
+  f = UTI_OpenFile(NULL, filename, NULL, 'r', 0);
+
+  if (f && fscanf(f, "%lf", &temp) == 1) {
+    comp = get_tempcomp(temp);
+
+    if (fabs(comp) <= MAX_COMP) {
+      comp = LCL_SetTempComp(comp);
+
+      DEBUG_LOG("tempcomp updated to %f for %f", comp, temp);
+
+      if (logfileid != -1) {
+        struct timespec now;
+
+        LCL_ReadCookedTime(&now, NULL);
+        LOG_FileWrite(logfileid, "%s %11.4e %11.4e",
+            UTI_TimeToLogForm(now.tv_sec), temp, comp);
+      }
+    } else {
+      LOG(LOGS_WARN, "Temperature compensation of %.3f ppm exceeds sanity limit of %.1f",
+          comp, MAX_COMP);
+    }
+  } else {
+    LOG(LOGS_WARN, "Could not read temperature from %s", filename);
+  }
+
+  if (f)
+    fclose(f);
+
+  timeout_id = SCH_AddTimeoutByDelay(update_interval, read_timeout, NULL);
+}
+
+static void
+read_points(const char *filename)
+{
+  FILE *f;
+  char line[256];
+  struct Point *p;
+
+  f = UTI_OpenFile(NULL, filename, NULL, 'R', 0);
+
+  points = ARR_CreateInstance(sizeof (struct Point));
+
+  while (fgets(line, sizeof (line), f)) {
+    p = (struct Point *)ARR_GetNewElement(points);
+    if (sscanf(line, "%lf %lf", &p->temp, &p->comp) != 2) {
+      LOG_FATAL("Could not read tempcomp point from %s", filename);
+      break;
+    }
+  }
+
+  fclose(f);
+
+  if (ARR_GetSize(points) < 2)
+    LOG_FATAL("Not enough points in %s", filename);
+}
+
+void
+TMC_Initialise(void)
+{
+  char *point_file;
+
+  CNF_GetTempComp(&filename, &update_interval, &point_file, &T0, &k0, &k1, &k2);
+
+  if (filename == NULL)
+    return;
+
+  if (update_interval <= 0.0)
+    update_interval = 1.0;
+
+  if (point_file)
+    read_points(point_file);
+
+  logfileid = CNF_GetLogTempComp() ? LOG_FileOpen("tempcomp",
+      "   Date (UTC) Time        Temp.       Comp.")
+    : -1;
+
+  read_timeout(NULL);
+}
+
+void
+TMC_Finalise(void)
+{
+  if (filename == NULL)
+    return;
+
+  if (points)
+    ARR_DestroyInstance(points);
+
+  SCH_RemoveTimeout(timeout_id);
+}