/* Copyright (C) 2021,2022 fef <owo@fef.moe>.  All rights reserved. */

#pragma once

#ifndef _ARCH_SCHED_H_
#error "This file is not meant to be included directly, use <arch/page.h>"
#endif

/**
 * @brief In-kernel context save for the x86.
 * This precise structure layout is hardcoded in assembly, so don't forget to
 * update `arch/x86/sys/i386/switch.S` if you need to change it.
 */
struct x86_context {
	/**
	 * The register itself is %esp, which points to the %eip that was pushed
	 * by the function calling `arch_switch_to()` as per the x86 SysV ABI
	 */
	union {
		register_t esp;
		register_t *eip;
	};
	register_t esi;
	register_t edi;
	register_t ebx;
	register_t ebp;
} __packed;

/**
 * @brief Arch dependent Task Control Block (i386 version).
 * This is what's required for in-kernel task switching.
 * Treat as a completely opaque type outside of the `arch/x86` directory.
 */
typedef struct i386_context tcb_t;