initial update_power_counter.sh

diff --git a/src/update_power_counter.sh b/src/update_power_counter.sh
new file mode 100755 (executable)
index 0000000..76ba6f3
--- /dev/null
+++ b/src/update_power_counter.sh
@@ -0,0 +1,66 @@
+#!/bin/bash
+#
+# update_power_counter.sh - query the S.M.A.R.T. data and store the state
+#
+# This fetches the current power count and stores it. It also prints the
+# previous power count state and the next expected state. This must be run as
+# root or as a user that has access to the specific device.
+#
+
+DEVICE="/dev/sda";
+STATE_DIR="/var/lib/smartmonster";
+PREVIOUS_POWER_COUNT_FILE="$STATE_DIR/previous_power_count";
+CURRENT_POWER_COUNT_FILE="$STATE_DIR/current_power_count";
+EXPECTED_POWER_COUNT_FILE="$STATE_DIR/expected_power_count";
+POWER_INCREMENT=1;
+
+if [ "$USER" != "root" ];
+then
+  echo "You must be root!";
+  exit 1;
+fi
+
+# XXX: Hello TOCTOU!
+if [ ! -d "$STATE_DIR" ];
+then
+  echo "You have no $STATE_DIR; creating it!";
+  mkdir -p $STATE_DIR;
+
+  if [ $? != 0 ];
+  then
+    echo "Unable to create $STATE_DIR!";
+    exit 1;
+  fi
+
+fi
+
+SMARTCTL="`which smartctl`";
+SMARTCTL_ARGS="-A";
+POWER_COUNT="Power_Cycle_Count"
+
+CURRENT_POWER_COUNT=`$SMARTCTL $SMARTCTL_ARGS $DEVICE|grep $POWER_COUNT|awk '{print $10}'`;
+
+if [ ! -f "$PREVIOUS_POWER_COUNT_FILE" ];
+then
+  echo "You have no $PREVIOUS_POWER_COUNT_FILE!";
+  echo "Assuming first run and populating with CURRENT_POWER_COUNT";
+  echo $CURRENT_POWER_COUNT > $PREVIOUS_POWER_COUNT_FILE;
+  echo $PREVIOUS_POWER_COUNT=$CURRENT_POWER_COUNT;
+else
+  PREVIOUS_POWER_COUNT="`cat $STATE_DIR/previous_power_count`";
+fi
+
+EXPECTED_NEXT_COUNT="$(expr $CURRENT_POWER_COUNT + $POWER_INCREMENT)";
+
+# Print/export the count data
+echo "PREVIOUS_POWER_COUNT=$PREVIOUS_POWER_COUNT";
+echo "CURRENT_POWER_COUNT=$CURRENT_POWER_COUNT";
+echo "EXPECTED_NEXT_COUNT=$EXPECTED_NEXT_COUNT";
+export PREVIOUS_POWER_COUNT=$PREVIOUS_POWER_COUNT;
+export CURRENT_POWER_COUNT=$CURRENT_POWER_COUNT;
+export EXPECTED_NEXT_COUNT=$EXPECTED_NEXT_COUNT;
+
+# Update the state files
+echo $PREVIOUS_POWER_COUNT > $PREVIOUS_POWER_COUNT_FILE;
+echo $CURRENT_POWER_COUNT > $CURRENT_POWER_COUNT_FILE;
+echo $EXPECTED_NEXT_COUNT > $EXPECTED_POWER_COUNT_FILE;