Save hwmon device paths and names in configuration file, and check them

before starting any fan control operation.


git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@5770 7894878c-1315-0410-8ee3-d5d059ff63e0

CHANGES

@@ -4,7 +4,9 @@ lm-sensors CHANGES file
 SVN-HEAD
   libsensors: Support upcoming sysfs path to i2c adapters
   fancontrol: Check that all referenced sysfs files exist
+              Check that all devices match the configuration file
   pwmconfig: Exit immediately if not root
+             Save device paths and names in configuration file
   sensors.conf.default: Encourage user to not modify this file
   sensors-detect: Refer to tmp401 driver if TMP411 is detected
                   Clean up the discovery of i2c adapters

prog/pwm/fancontrol

@@ -3,12 +3,12 @@
 # Simple script implementing a temperature dependent fan speed control
 # Supported Linux kernel versions: 2.6.5 and later
 #
-# Version 0.69
+# Version 0.70
 #
 # Usage: fancontrol [CONFIGFILE]
 #
 # Dependencies:
-#   bash, egrep, sed, cut, sleep, lm_sensors :)
+#   bash, egrep, sed, cut, sleep, readlink, lm_sensors :)
 #
 # Please send any questions, comments or success stories to
 # marius.reiner@hdev.de
@@ -55,6 +55,8 @@ function LoadConfig {
 
 	# grep configuration from file
 	INTERVAL=`egrep '^INTERVAL=.*$' $1 | sed -e 's/INTERVAL=//g'`
+	DEVPATH=`egrep '^DEVPATH=.*$' $1 | sed -e 's/DEVPATH= *//g'`
+	DEVNAME=`egrep '^DEVNAME=.*$' $1 | sed -e 's/DEVNAME= *//g'`
 	FCTEMPS=`egrep '^FCTEMPS=.*$' $1 | sed -e 's/FCTEMPS=//g'`
 	MINTEMP=`egrep '^MINTEMP=.*$' $1 | sed -e 's/MINTEMP=//g'`
 	MAXTEMP=`egrep '^MAXTEMP=.*$' $1 | sed -e 's/MAXTEMP=//g'`
@@ -152,6 +154,57 @@ function LoadConfig {
 	echo
 }
 
+function DevicePath()
+{
+	if [ -h "$1/device" ]
+	then
+		readlink -f "$1/device" | sed -e 's/^\/sys\///'
+	fi
+}
+
+function DeviceName()
+{
+	if [ -r "$1/name" ]
+	then
+		cat "$1/name" | sed -e 's/[[:space:]=]/_/g'
+	elif [ -r "$1/device/name" ]
+	then
+		cat "$1/device/name" | sed -e 's/[[:space:]=]/_/g'
+	fi
+}
+
+function ValidateDevices()
+{
+	local OLD_DEVPATH="$1" OLD_DEVNAME="$2" outdated=0
+	local entry device name path
+
+	for entry in $OLD_DEVPATH
+	do
+		device=`echo "$entry" | sed -e 's/=[^=]*$//'`
+		path=`echo "$entry" | sed -e 's/^[^=]*=//'`
+
+		if [ "`DevicePath "$device"`" != "$path" ]
+		then
+			echo "Device path of $device has changed"
+			outdated=1
+		fi
+	done
+
+	for entry in $OLD_DEVNAME
+	do
+		device=`echo "$entry" | sed -e 's/=[^=]*$//'`
+		name=`echo "$entry" | sed -e 's/^[^=]*=//'`
+
+		if [ "`DeviceName "$device"`" != "$name" ]
+		then
+			echo "Device name of $device has changed"
+			outdated=1
+		fi
+	done
+
+	return $outdated
+}
+
 # Check that all referenced sysfs files exist
 function CheckFiles {
 	local outdated=0
@@ -232,6 +285,17 @@ then
 fi
 cd $DIR
 
+# Check for configuration change
+if [ -z "$DEVPATH" -o -z "$DEVNAME" ]
+then
+	echo "Configuration is too old, please run pwmconfig again"
+	exit 1
+fi
+if ! ValidateDevices "$DEVPATH" "$DEVNAME"
+then
+	echo "Configuration appears to be outdated, please run pwmconfig again"
+	exit 1
+fi
 CheckFiles || exit 1
 
 if [ -f "$PIDFILE" ]

prog/pwm/fancontrol.8

@@ -38,13 +38,21 @@ variables available for changing \fBfancontrol\fP's behaviour:
 This variable defines at which interval in seconds the main loop of
 \fBfancontrol\fP will be executed
 .TP
+.B DEVPATH
+Maps hwmon class devices to physical devices. This lets \fBfancontrol\fP
+check that the configuration file is still up-to-date.
+.TP
+.B DEVNAME
+Records hwmon class device names. This lets \fBfancontrol\fP check that
+the configuration file is still up-to-date.
+.TP
 .B FCTEMPS
 Maps PWM outputs to temperature sensors so \fBfancontrol\fP knows which
 temperature sensors should be used for calculation of new values for
 the corresponding PWM outputs.
 .TP
 .B FCFANS
-FCFANS records the association between a PWM and a fan.
+Records the association between a PWM output and a fan input.
 Then \fBfancontrol\fP can check the fan speed and restart it if it
 stops unexpectedly.
 .TP
@@ -92,9 +100,11 @@ You have to play with the temperature values a bit to get happy. For initial
 setup I recommend using the \fBpwmconfig\fP script. Small changes can be made by
 editing the config file directly following the rules above.
 
-Upon starting, fancontrol will make sure that all referenced sysfs files
-do exist. If not, it will quit immediately, upon the assumption that the
-configuration file may be out-of-sync with the loaded kernel drivers.
+Upon starting, fancontrol will make sure that all referenced devices
+do exist and match what they were at configuration time, and that all
+referenced sysfs files do exist. If not, it will quit immediately, upon
+the assumption that the configuration file may be out-of-sync with the
+loaded kernel drivers.
 
 .SH THE ALGORITHM
 

prog/pwm/pwmconfig

@@ -539,6 +539,57 @@ then
 	exit 1
 fi
 
+function DevicePath()
+{
+	if [ -h "$1/device" ]
+	then
+		readlink -f "$1/device" | sed -e 's/^\/sys\///'
+	fi
+}
+
+function DeviceName()
+{
+	if [ -r "$1/name" ]
+	then
+		cat "$1/name" | sed -e 's/[[:space:]=]/_/g'
+	elif [ -r "$1/device/name" ]
+	then
+		cat "$1/device/name" | sed -e 's/[[:space:]=]/_/g'
+	fi
+}
+
+function ValidateDevices()
+{
+	local OLD_DEVPATH="$1" OLD_DEVNAME="$2" outdated=0
+	local entry device name path
+
+	for entry in $OLD_DEVPATH
+	do
+		device=`echo "$entry" | sed -e 's/=[^=]*$//'`
+		path=`echo "$entry" | sed -e 's/^[^=]*=//'`
+
+		if [ "`DevicePath "$device"`" != "$path" ]
+		then
+			echo "Device path of $device has changed"
+			outdated=1
+		fi
+	done
+
+	for entry in $OLD_DEVNAME
+	do
+		device=`echo "$entry" | sed -e 's/=[^=]*$//'`
+		name=`echo "$entry" | sed -e 's/^[^=]*=//'`
+
+		if [ "`DeviceName "$device"`" != "$name" ]
+		then
+			echo "Device name of $device has changed"
+			outdated=1
+		fi
+	done
+
+	return $outdated
+}
+
 function AskPath()
 {
 	echo -n 'What should be the path to your fancontrol config file (/etc/fancontrol)? '
@@ -566,6 +617,8 @@ function ClearConfig()
 
 function LoadConfig()
 {
+	local OLD_DEVPATH OLD_DEVNAME
+
 	# Nothing to do
 	if [ ! -f "$1" ]
 	then
@@ -575,6 +628,8 @@ function LoadConfig()
 
 	echo "Loading configuration from $1 ..."
 	INTERVAL=`egrep '^INTERVAL=.*$' $1 | sed -e 's/INTERVAL= *//g'`
+	OLD_DEVPATH=`egrep '^DEVPATH=.*$' $1 | sed -e 's/DEVPATH= *//g'`
+	OLD_DEVNAME=`egrep '^DEVNAME=.*$' $1 | sed -e 's/DEVNAME= *//g'`
 	FCTEMPS=`egrep '^FCTEMPS=.*$' $1 | sed -e 's/FCTEMPS= *//g'`
 	FCFANS=`egrep '^FCFANS=.*$' $1 | sed -e 's/FCFANS= *//g'`
 	MINTEMP=`egrep '^MINTEMP=.*$' $1 | sed -e 's/MINTEMP= *//g'`
@@ -585,16 +640,12 @@ function LoadConfig()
 	MAXPWM=`egrep '^MAXPWM=.*$' $1 | sed -e 's/MAXPWM= *//g'`
 
 	# Check for configuration change
-	local item
-	for item in $FCFANS
-	do
-		if [ ! -f "`echo $item | sed -e 's/=.*$//'`" ]
-		then
-			echo "Configuration appears to be outdated, discarded"
-			ClearConfig
-			return 0
-		fi
-	done
+	if ! ValidateDevices "$OLD_DEVPATH" "$OLD_DEVNAME"
+	then
+		echo "Configuration appears to be outdated, discarded"
+		ClearConfig
+		return 0
+	fi
 }
 
 LoadConfig $FCCONFIG
@@ -675,14 +726,68 @@ function TestMinStop()
 	echo "OK, using $fanval"
 }
 
+# Remember the path and name of each device with at least one
+# reference (pwm, temp or fan) in the configuration file.
+# This function sets globals DEVPATH and DEVNAME as a side effect.
+function RememberDevices()
+{
+	local used entry device name path tempfandev pwmdev
+	DEVPATH=""
+	DEVNAME=""
+
+	for device in $DEVICES
+	do
+		device=`echo "$device" | sed -e 's/\/.*$//'`
+
+		used=0
+		for entry in $1 $2
+		do
+			pwmdev=`echo "$entry" | sed -e 's/\/.*$//'`
+			tempfandev=`echo "$entry" | sed -e 's/^[^=]*=//' -e 's/\/.*$//'`
+
+			if [ "$device" = "$pwmdev" -o "$device" = "$tempfandev" ]
+			then
+				used=1
+			fi
+		done
+		if [ "$used" -eq 0 ]
+		then
+			continue
+		fi
+
+		# Record the device path and name. This lets the fancontrol
+		# script check that they didn't change. If they did, then the
+		# configuration file can no longer be trusted.
+		path=`DevicePath "$device"`
+		if [ -z "$DEVPATH" ]
+		then
+			DEVPATH="$device=$path"
+		else
+			DEVPATH="$DEVPATH $device=$path"
+		fi
+
+		name=`DeviceName "$device"`
+		if [ -z "$DEVNAME" ]
+		then
+			DEVNAME="$device=$name"
+		else
+			DEVNAME="$DEVNAME $device=$name"
+		fi
+	done
+}
+
 function SaveConfig()
 {
+	RememberDevices "$FCTEMPS" "$FCFANS"
+
 	echo
 	echo "Saving configuration to $FCCONFIG..."
 	tmpfile=`mktemp -t pwmcfg.XXXXXXXXXX` || { echo "$0: Cannot create temporary file" >&2; exit 1;  }
 	trap " [ -f \"$tmpfile\" ] && /bin/rm -f -- \"$tmpfile\"" 0 1 2 3 13 15
 	echo "# Configuration file generated by pwmconfig, changes will be lost" >$tmpfile
 	echo "INTERVAL=$INTERVAL" >>$tmpfile
+	echo "DEVPATH=$DEVPATH" >>$tmpfile
+	echo "DEVNAME=$DEVNAME" >>$tmpfile
 	echo "FCTEMPS=$FCTEMPS" >>$tmpfile
 	echo "FCFANS=$FCFANS" >>$tmpfile
 	echo "MINTEMP=$MINTEMP" >>$tmpfile