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diff --git a/ksysguard/ksysguardd/Porting-HOWTO b/ksysguard/ksysguardd/Porting-HOWTO new file mode 100644 index 000000000..4576783bc --- /dev/null +++ b/ksysguard/ksysguardd/Porting-HOWTO @@ -0,0 +1,133 @@ +This document describes the interface between ksysguard and +ksysguardd. ksysguardd is started as a child of ksysguard, either +directly or via a shell. Alternatively a ksysguardd can listen on a +port and a single instance can then be used by multiple instances of +ksysguard. + +This client/server design was chosen, because on some operating +systems the back-end needs elevated permissions. Since C++ programs +should NEVER have setgid/setuid permissions, a plain C back-end was +needed. It also allowed for an easy network support using existing +security mechanisms (ssh). + +ksysguard sends commands and ksysguardd answers to them. Each answer +ends with the string "\nksysguardd> ". Error messages are enclosed in +ESC '\033' characters. Therefor regular messages may never contain +ESC. The set of commands that each ksysguardd implementation supports +can be very different. There are only a very few mandatory command and +a few recommended commands. + +The mandatory commands are 'monitors', 'test' and 'quit'. +The recommended commands are: + +cpu/idle +cpu/sys +cpu/nice +cpu/user +mem/swap/free +mem/swap/used +mem/physical/cached +mem/physical/buf +mem/physical/application +mem/physical/used +mem/physical/free +ps +pscount + +Without these commands KSysGuard is not very helpful. + +The 'monitors' command returns the list of available sensors. The +output looks like this: + +-------- +mem/physical/free integer +ps table +pscount integer +ksysguardd> +-------- + +Sensor names can be hierarchical. Each level is separated by a +/. ksysguard uses a tree widget in the SensorBrowser to display the +commands in a tree. Every sensor name must be followed by the type of +the sensor separated by a tab. Currently 4 different types of sensors +are supported, integer, float, listview and table. The table sensor +returns the information for the ProcessController widget. listview +sensors use a generic table to display information. To find out more +about a sensor an additional command must be implemented for each +sensor that has a questionmark appended to the sensor name. It can be +used to find out more about the sensor. + +-------- +ksysguardd> mem/physical/free? +Free Memory 0 260708 KB +ksysguardd> +-------- + +integer and float sensor return a short description, the minimum and +maximum value and the unit. All fields are again separated by +tabs. The minimum and maximum values can both be 0 to trigger the +auto-range feature of the display. + +-------- +ksysguardd> ps? +Name PID PPID UID GID Status User% System% Nice VmSize VmRss VmLib Login Command +s d d d d S f f d d sksysguardd> +-------- + +This is the output of the ps? inquiry command. The ps command is the +only recommended command. The answer to ps? consists of 2 lines. Both +lines have the same number of fields each separated by a tab. The +first line specifies the name of the columns and the second the type +of the values in the column. + +d: integer value +D: integer value that should be localized in the frontend +f: floating point value +s: string value +S: string value that needs to be translated + Strings must be added to the ProcessList::columnDict dictionary. + +For the ProcessController to function properly the Name and PID +columns are mandatory. All other columns are optional and their +content may be implementation dependant. It is highly recommended not +to deviate from the Linux implementation unless absolutely +unavoidable, in order to provide a consistent interface across all +platforms. + +The 'test' command can be used by the front-end to find out if a +certain other command is supported by this version of ksysguardd. The +command returns "1\n" if the command is supported and "0\n" if the +command is not supported. + +The 'quit' command terminates ksysguardd. + +ksysguardd may support dynamic monitor sets. If a CPU is added or an +interface disabled, monitors may be added or removed. To notify the +front-end about this, you need to send the string "RECONFIGURE\n" over +stderr. This causes the front-end to request the list of monitors +again and adapt it's layout accordingly. If ksysguardd receives a +command it doesn't know it has to reply with "UNKNOWN +COMMAND\nksysguardd> ". + +ksysguardd does not handle native language support. In order to have a +minimum installation (only a single file) on the monitored machine, +all translation are handled by the front-end. Please see the files +gui/ksgrd/SensorManger.cc and gui/SensorDisplayLib/ProcessTable.cc +if you add new strings. + +/** + * Since I'm very much a C++ guy I've written some functions which + * provide a similar functionality as template classes for lists and + * arrays. The Linux implementation uses them. Feel free to use them for + * the ports as well if you like. The interface is described in + * CContLib/ccont.h. Unfortunately I still haven't found time to document + * it properly, but the use should be fairly obvious. + */ + +Chris <[email protected]> + +Since the above mentioned CContLib was a little slow I reimplement it and +wrote some docu stuff in the header file. If you need an example for use +look at ksysguardd/Linux/diskstat.(h|c). + +Tobias <[email protected]> |