/*
 * Header file for CS325 thread library
 * Copyright  2008 Anthony Martinez
 */

#ifndef __LIBTHREAD_H
#define __LIBTHREAD_H

#include <stdlib.h>
#include <setjmp.h>

#define JMPBUF jmp->__jmpbuf
#define EBX 0
#define ESP 1
#define EBP 2
#define ESI 3
#define EDI 4
#define EIP 5

#ifdef DEBUG
#    define Dprintf(...) fprintf(stderr, __VA_ARGS__)
#else
#    define Dprintf(...)
#endif

#define new_thread_state() (thread_state_t*)calloc(1, sizeof(thread_state_t))

#define THREAD_STACK_SIZE (10*1024)

typedef struct thread_state {
    struct thread_state *prev, *next;
    unsigned int id;
    unsigned int eax, ebx, ecx, edx;
    unsigned int *esi, *edi, *ebp, *esp, *eip;
} thread_state_t;

typedef struct queue_head {
    thread_state_t *head;
    thread_state_t *tail;
} queue_head_t;

unsigned int  thread_create(void *function);
void begin_threads(void);
void thread_suspend(void);
void thread_switch(unsigned int id); /* uh yield? */
void thread_wakeup(unsigned int id);

#ifdef DEBUG
#    define ensure_queue(qq); if(!qq) { fprintf(stderr, "null queue in %s", __FUNCTION__); abort(); }
#else
#    define ensure_queue(qq);
#endif

void _enqueue(queue_head_t *q, thread_state_t *new);
thread_state_t *_dequeue(queue_head_t *q);
thread_state_t *_peek(queue_head_t *q);

#endif /* __LIBTHREAD_H */