Break ON
; vim>600:filetype=kix sw=3 ts=3
; vim>600:fdm=marker fdc=4

; Generic multi task launcher
$gNull=SetOption("Explicit","ON")
$gNull=SetOption("ASCII","ON")
$gNull=SetOption("WrapAtEol","ON")

Global $gControlFile
Dim $iMaxThreads,$sKixCommand

;********************************************************************************************
;************************BEGIN CUSTOMISED VARIABLE DEFINITION********************************
; Change the next three variable definitions to fit local requirements                      *
$gControlFile=@SCRIPTDIR+"\MultiTask.ini"   ; Main control file.                            *
$iMaxThreads=10                             ; Maximum child processes to start              *
$sKixCommand="kix32.exe"                    ; KiXtart command used to start child processes *
;*************************END CUSTOMISED VARIABLE DEFINITION*********************************
;********************************************************************************************

; Decide if this is a child or parent task
If IsDeclared($gChildName)      ; Child task.
   $gNull=WriteProfileString($gControlFile,"STATUS",$gChildName,udfChildTask($gChildName,$gChildParameter))
Else                             ; Parent task
   Dim $sChildParameter                     ; New thread parameter
   Dim $sChildName                          ; Child name
   Dim $iChildCount                         ; How many child processes are active

   "Parent starting, maximum threads="+$iMaxThreads+@CRLF

   ; Set up control file
   If RedirectOutput($gControlFile,1)
      "FATAL: Cannot open control file for writing!"+@CRLF
      "  Error: "+@ERROR+", "+@SERROR+@CRLF
      Exit 1
   EndIf
   "[STATUS]"+@CRLF
   "[ACKNOWLEDGED]"+@CRLF
   $gNull=RedirectOutput("")

   If udfInitialiseParent()
      "ERROR: Cannot initialise parent process."+@CRLF
      Exit 1
   Else
      "Parent initialisation complete.  Let's go ta woik..."+@CRLF

      ; Get each child process
      $sChildParameter=udfEnumChildParameter()
      While $sChildParameter
         $sChildName="Child_"+Right("000000"+(Val(SubStr($sChildName,7))+1),6)
         ; Wait until a slot is available
         While $iChildCount=$iMaxThreads $iChildCount=$iChildCount-udfCheckStatus() Loop
         ; Launch child
         $iChildCount=$iChildCount+1
         Run $sKixCommand+' '+@SCRIPTDIR+'\'+@SCRIPTNAME+' $$gChildName='+$sChildName+' $$gChildParameter="'+$sChildParameter+'"'
         $sChildParameter=udfEnumChildParameter()
      Loop

      ; Wait for all tasks to complete
      "All child tasks started - waiting for "+$iChildCount+" to complete"+@CRLF
      While $iChildCount $iChildCount=$iChildCount-udfCheckStatus() Loop
      "Run completed."+@CRLF
EndIf

Exit 0

; This routine will check the status of running jobs and return the number that have completed.
Function udfCheckStatus() ; {{{
   Dim $sChildName,$sStatus
   $udfCheckStatus=0
   For Each $sChildName In Split(ReadProfileString($gControlFile,"STATUS",""),Chr(10))
      If $sChildName
         $udfCheckStatus=$udfCheckStatus+1
         $sStatus=ReadProfileString($gControlFile,"STATUS",$sChildName)
         $sChildName+" reports completion status: "+$sStatus+@CRLF
         $gNull=WriteProfileString($gControlFile,"STATUS",$sChildName,"")
         $gNull=WriteProfileString($gControlFile,"ACKNOWLEDGED",$sChildName,$sStatus)
      EndIf
   Next
   ; Sleep a little to give up CPU between checks *IF* no jobs have completed.
   If Not $udfCheckStatus Sleep 0.2 EndIf
EndFunction ; }}}

;----------------------------------------------------------------------------
;---------------------BEGIN CUSTOMISATION SECTION----------------------------
; Change the UDFS below this point to customise the multithreaded process.
; The demo code lines are all labelled "*DEMO*", change or remove as needed.

; Parent initialisation.
;   Use this to set up structures and variables for the udfEnumChildParameter()
;   Don't forget to make variables global if they are going to be used in the
;   subsequent functions.
;
; The *DEMO* initialisation code will open a text input file.
;
Function udfInitialiseParent() ; {{{
   $udfInitialiseParent=0  ; Default to "OK" state
   Global $gfhInput                                        ; *DEMO*
   $gfhInput=FreeFileHandle()                              ; *DEMO*
   If Not $gfhInput                                        ; *DEMO*
      "Fatal: Cannot allocate file handle"+@CRLF           ; *DEMO*
      $udfInitialiseParent=1                               ; *DEMO*
      Exit 1                                               ; *DEMO*
   EndIf                                                   ; *DEMO*
   If Open($gfhInput,"input.txt")                          ; *DEMO*
      "Fatal: Cannot open input file"+@CRLF                ; *DEMO*
      $udfInitialiseParent=1                               ; *DEMO*
      Exit 1                                               ; *DEMO*
   EndIf                                                   ; *DEMO*
   Exit 0
EndFunction ; }}}

; Enumerate child parameter.
;  Each time this function is called it should return a value which will be
;  passed to the new thread as a parameter.  It should return a null value when
;  all thread parameters have been exhausted.
;
; The *DEMO* code will return a line from the input file opened in the parent
; initialisation each time it is called
;
Function udfEnumChildParameter() ; {{{
   $udfEnumChildParameter="" ; Default to "List exhausted" state

   $udfEnumChildParameter=ReadLine($gfhInput)              ; *DEMO*
   If @ERROR $udfEnumChildParameter="" EndIf               ; *DEMO*
   Exit 0
EndFunction ; }}}

; Child task.
;   When a new thread is launched this function is called with the child parameter
;   The function should return a string representing the status to be returned to
;   the parent.
;
; The *DEMO* code just sleeps a random number of seconds, then returns the
; paramater in the status
Function udfChildTask($sName,$sParameter) ; {{{
   $udfChildTask="0 OK" ; Default success message

   Srnd(@MSECS*1000+Val(Right($sName,6)))                  ; *DEMO*
   Sleep 3+Rnd(15)                                         ; *DEMO*
   $udfChildTask="0 '"+$sParameter+"'"                     ; *DEMO*
   Exit 0
EndFunction ; }}}