package core:sys/kqueue

Source

Filter :: enum _Filter_Backing {
	Read   = -1, // Check for read availability on the file descriptor.
	Write  = -2, // Check for write availability on the file descriptor.
	AIO    = -3, // Attached to AIO requests.
	VNode  = -4, // Check for changes to the subject file.
	Proc   = -5, // Check for changes to the subject process.
	Signal = -6, // Check for signals delivered to the process.
	Timer  = -7, // Timers.
}

Flag :: enum _Flags_Backing {
	Add      = 0,  // Add event to kq (implies .Enable).
	Delete   = 1,  // Delete event from kq.
	Enable   = 2,  // Enable event.
	Disable  = 3,  // Disable event (not reported).
	One_Shot = 4,  // Only report one occurrence.
	Clear    = 5,  // Clear event state after reporting.
	Receipt  = 6,  // Force immediate event output.
	Dispatch = 7,  // Disable event after reporting.
	Error    = 14, // Error, data contains errno.
	EOF      = 15, // EOF detected.
}

Flags :: bit_set[Flag; _Flags_Backing]

KEvent :: struct #align (4) {
	// Value used to identify this event. The exact interpretation is determined by the attached filter.
	ident:  uintptr,
	// Filter for event.
	filter: Filter,
	// General flags.
	flags:  bit_set[Flag; _Flags_Backing],
	// Filter specific flags.
	fflags: struct #raw_union {
		rw:    bit_set[RW_Flag; u32],
		vnode: bit_set[VNode_Flag; u32],
		fproc: bit_set[Proc_Flag; u32],
		// vm:    VM_Flags,
		timer: bit_set[Timer_Flag; u32],
	},
	// Filter specific data.
	data:   i64,
	// Opaque user data passed through the kernel unchanged.
	udata:  rawptr,
}

KQ :: posix.FD

Proc_Flag :: enum u32 {
	Exit   = 31, // Process exited.
	Fork   = 30, // Process forked.
	Exec   = 29, // Process exec'd.
	Signal = 27, // Shared with `Filter.Signal`.
}

Proc_Flags :: bit_set[Proc_Flag; u32]

RW_Flag :: enum u32 {
	Low_Water_Mark = 0, 
}

RW_Flags :: bit_set[RW_Flag; u32]

Timer_Flag :: enum u32 {
	Seconds  = 0, // Data is seconds.
	USeconds = 1, // Data is microseconds.
	NSeconds = 2, // Data is nanoseconds.
	Absolute = 3, // Absolute timeout.
}

Timer_Flags :: bit_set[Timer_Flag; u32]

VNode_Flag :: enum u32 {
	Delete = 0, // Deleted.
	Write  = 1, // Contents changed.
	Extend = 2, // Size increased.
	Attrib = 3, // Attributes changed.
	Link   = 4, // Link count changed.
	Rename = 5, // Renamed.
	Revoke = 6, // Access was revoked.
}

VNode_Flags :: bit_set[VNode_Flag; u32]

kevent :: proc(kq: posix.FD, change_list: []KEvent, event_list: []KEvent, timeout: ^libc.timespec) -> (n_events: i32, err: posix.Errno) {…}

kqueue :: proc() -> (kq: posix.FD, err: posix.Errno) {…}