- 1 year ago
How do I convert a Windows IO completion port HANDLE to a GLib's GPollFD for a custom GSource?
To convert a Windows IO completion port HANDLE
to a GLib's GPollFD
structure for use in a custom GSource, you can follow these steps:
- Import the required libraries and define the necessary structures and functions:
c#include <glib.h>
#include <windows.h>
typedef struct {
GSource source;
GPollFD poll_fd;
HANDLE io_completion_port;
} MyCustomSource;
gboolean my_custom_source_prepare(GSource* source, gint* timeout);
gboolean my_custom_source_check(GSource* source);
gboolean my_custom_source_dispatch(GSource* source, GSourceFunc callback, gpointer user_data);
In the above code, MyCustomSource
is a custom structure that contains a GSource
, GPollFD
, and the Windows IO completion port HANDLE
. You should define the necessary functions for the custom source: my_custom_source_prepare
, my_custom_source_check
, and my_custom_source_dispatch
.
- Implement the
my_custom_source_prepare
function:
cgboolean my_custom_source_prepare(GSource* source, gint* timeout) {
MyCustomSource* custom_source = (MyCustomSource*)source;
// Set the poll events to monitor
custom_source->poll_fd.events = G_IO_IN;
// Set the timeout to -1 for no timeout
*timeout = -1;
return TRUE;
}
In the my_custom_source_prepare
function, you set the poll events to monitor. In this example, G_IO_IN
is used for input events. You can modify this as per your specific requirements. The timeout is set to -1
to indicate no timeout.
- Implement the
my_custom_source_check
function:
cgboolean my_custom_source_check(GSource* source) {
MyCustomSource* custom_source = (MyCustomSource*)source;
// Check if the HANDLE is ready for IO
DWORD bytes_transferred;
ULONG_PTR completion_key;
LPOVERLAPPED overlapped;
BOOL result = GetQueuedCompletionStatus(
custom_source->io_completion_port,
&bytes_transferred,
&completion_key,
&overlapped,
0 // Non-blocking call
);
if (result || GetLastError() == WAIT_TIMEOUT) {
return TRUE;
}
// Error occurred, handle the error if needed
// ...
return FALSE;
}
In the my_custom_source_check
function, you use the GetQueuedCompletionStatus
function to check if the IO completion port handle is ready for IO. If the function returns successfully or if the error is WAIT_TIMEOUT
, you return TRUE
to indicate that the source is ready. Otherwise, you can handle the error or other conditions based on your requirements.
- Implement the
my_custom_source_dispatch
function:
cgboolean my_custom_source_dispatch(GSource* source, GSourceFunc callback, gpointer user_data) {
// Call the callback function or perform necessary operations
// ...
return G_SOURCE_CONTINUE;
}
In the my_custom_source_dispatch
function, you can call the provided callback function or perform any other necessary operations based on the readiness of the IO completion port handle. Modify this function to meet your specific needs.
With these steps, you have converted a Windows IO completion port HANDLE
to a GLib's GPollFD
structure for use in a custom GSource. You can now utilize the custom GSource in your GLib-based application or event loop.