OpenEuphoria

threads further testing

• Posted by jacques deschênes <desja at globetrotter.net> Jul 10, 2006
• 528 views

I made more testing of threads in euphoria.
if I run my test code with exw.exe it crash.
if I run it with exwc.exe it run nice.
I tested writting to console using puts() an nothing is printed to screen but
not crash.
I replaced puts() by win32api function  WriteConsole() and it works fine.

temporary conclusions: 
1)if one avoid call to statically linked C run time functions from threads it
works.
2) exwc.exe  seem to be thread safe  but not exw.exe.
3) So one can write multi-threaded console apps in euphoria

platform tested on: windows xp sp2
euphoria interpreter:  exwc.exe version 2.5  

my last test code:

-- testing windows system threads in euphoria

without warning

include wildcard.e
include misc.e
include machine.e
include dll.e

constant kernel32=open_dll("kernel32.dll")

if kernel32 = -1 then 
  puts(1,"failed to open kernel32.dll\n")
  abort(1)
end if

constant 
  CREATE_SUSPENDED = 4,
  STD_OUTPUT_HANDLE = -11
  
constant
iCreateThread=define_c_func(kernel32,"CreateThread",{C_POINTER,C_UINT,C_POINTER,C_POINTER,C_UINT,C_POINTER},C_UINT),
  iSleep=define_c_proc(kernel32,"Sleep",{C_UINT}),
  iCloseHandle = define_c_func(kernel32,"CloseHandle",{C_UINT},C_UINT),
  iResumeThread = define_c_func(kernel32,"ResumeThread",{C_UINT},C_UINT),
  iGetStdHandle = define_c_func(kernel32,"GetStdHandle",{C_UINT},C_UINT),
iWriteConsole =
  define_c_func(kernel32,"WriteConsoleA",{C_UINT,C_POINTER,C_UINT,C_POINTER,C_POINTER},C_UINT)
  
global function CreateThread(atom lpThreadAttributes,
atom dwStackSize,  -- initial thread stack size, in
                            bytes
atom lpStartAddress,      -- pointer to thread
                            function
                            atom lpParameter, -- argument for new thread 
                            atom dwCreationFlags,      -- creation flags 
atom lpThreadId  -- pointer to returned thread
                            identifier
                            )
return
  c_func(iCreateThread,{lpThreadAttributes,dwStackSize,lpStartAddress,lpParameter,dwCreationFlags,lpThreadId})
end function --CreateThread()

global function CloseHandle(atom handle)
  return c_func(iCloseHandle,{handle})
end function -- CloseHandle()

global procedure Sleep(integer ms)
  c_proc(iSleep,{ms})
end procedure

global function GetStdHandle(atom nStdHandle)
  return c_func(iGetStdHandle,{nStdHandle})
end function

global procedure WriteConsole(atom hConsole, sequence text)
atom void, pText, pCharWritten
  pText = allocate_string(text)
  pCharWritten =allocate(4)
  void = c_func(iWriteConsole,{hConsole,pText,length(text),pCharWritten,0})
  free(pText)
  free(pCharWritten)
end procedure

object fnVal
atom counter, spinlock


function IncCounter(atom param)-- thread function  (increment couter global
variable)
atom stdout
stdout = GetStdHandle(STD_OUTPUT_HANDLE) -- handle not inherited, get it from
  parent process.
  WriteConsole(stdout,"writing to console from IncCounter thread\n")
while 1 do
  if spinlock = 1 then
    counter +=1
    if counter = 10 then spinlock = 2 return 0 end if -- thread termination
    spinlock = 0
  else
    --sleep(500)  this does not work propably call static linked crt function.
    Sleep(500)  win32api wrapper work
   
  end if
end while
end function

atom lpStartAddress   lpStartAddress = call_back(routine_id("IncCounter")) 
atom lpThreadId  lpThreadId = allocate(4)
atom lpParam   lpParam = allocate(4)  poke4(lpParam,0)
atom hThread

hThread = CreateThread(0,0,lpStartAddress,lpParam,0,lpThreadId)
printf(1,"thread handle %d\n", hThread)
if not hThread then  puts(1, "echec creation thread\n") abort(0) end if
counter = 0
spinlock = 0
while spinlock < 2 do
 if not spinlock then
   ? counter
   spinlock = 1 
 end if
end while
fnVal = CloseHandle(hThread)

regards,
Jacques Deschênes