Threads and Oxygen

[Charles Pegge]

Elementary Threads Example:

Based on some code from MSDN.

This code is available in the Examples folder.




'-----------------------------------------
'EXTERN BLOCKS
'=========================================


Uses "oxygen"
Dim c,src As String
dim v as long
src="


#basic


#define NULL 0
#define FALSE 0
#define TRUE 1
#define IGNORE 0 'Ignore signal
#define INFINITE 0xFFFFFFFF 'Infinite timeout

#define __in
#define __out
#define __in_opt
#define __out_opt
#define __in_ecount(nCount)

#define MAX_THREADS 3

'Sample custom data structure for threads to use.
'This is passed by void pointer so it can be any data type
'that can be passed using a single void pointer (LPVOID).

type dtype
val1 as sys
val2 as sys
end type

typedef sys HANDLE,SIZE_T
typedef void *LPVOID, *LPSECURITY_ATTRIBUTES, *LPTHREAD_START_ROUTINE
typedef dword *LPDWORD

'================================
extern stdcall lib "kernel32.dll"
'================================


HANDLE CreateThread
(
__in_opt LPSECURITY_ATTRIBUTES lpThreadAttributes,
__in SIZE_T dwStackSize,
__in LPTHREAD_START_ROUTINE lpStartAddress,
__in_opt LPVOID lpParameter,
__in DWORD dwCreationFlags,
__out_opt LPDWORD lpThreadId
)


DWORD WaitForMultipleObjects
(
__in DWORD nCount,
__in_ecount(nCount) CONST HANDLE *lpHandles,
__in BOOL bWaitAll,
__in DWORD dwMilliseconds
)



BOOL CloseHandle
(
__in HANDLE hObject
)


end extern

#define MAX_THREADS 3

sys counter

'-------------------------------------------------
function MyThreadFunction( sys p ) as sys external
'=================================================
inc counter
return 0
end function



'--------------
function main()
'==============

dtype tdata[MAX_THREADS]
sys dwThreadIdArray[MAX_THREADS]
handle hThreadArray[MAX_THREADS]

dim as sys i

'Create MAX_THREADS worker threads.

for i=1 to MAX_THREADS
{
'Generate unique data for each thread to work with.

tdata[i].val1=i : tdata[i].val2=i+100

'Create the thread to begin execution on its own.

hThreadArray[i] = CreateThread
(
byval NULL, 'default security attributes
0, 'use default stack size
byval &MyThreadFunction, 'thread function name
tdata[i], 'argument to thread function
0, 'use default creation flags
dwThreadIdArray[i] 'returns the thread identifier
)

print "ThreadID: " dwThreadIdArray[i]

'Check the return value for success.
'If CreateThread fails, terminate execution.
'This will automatically clean up threads and memory.
'
} 'End of main thread creation loop.

'Wait until all threads have terminated.

WaitForMultipleObjects(MAX_THREADS, hThreadArray, TRUE, INFINITE)

'Close all thread handles and free memory allocations.

for i=1 to MAX_THREADS { CloseHandle( hThreadArray[i] ) }

return 0

end function

main()

print counter


"
'msgbox 0,O2_prep src+o2_error
O2_asmo src
if Len(O2_ERROR) Then
msgbox 0,O2_ERROR
else
o2_exec
end if