code: purgatorio

ref: a8083462e62459b2ae8a243dc4ba88416eba03b1
dir: /os/port/discall.c/

#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "../port/error.h"
#include <isa.h>
#include <interp.h>
#include "kernel.h"

#define	QP(l)	(Prog**)((char*)(l)+sizeof(QLock))

void*
libqlowner(void *l)
{
	return *QP(l);
}

void
libqlock(void *l)
{
	Prog *p;
	QLock *q;

	q = l;
	p = currun();
	if(p == nil)
		panic("libqlock");

	if(!canqlock(q)) {
		release();
		qlock(q);
		acquire();
	}
	*QP(l) = p;
}

void
libqunlock(void *l)
{
	Prog *p;
	QLock *q;

	q = l;
	p = currun();
	if(p == nil)
		panic("libqunlock 1");
	if(*QP(l) != p)
		panic("libqunlock 2");

	*QP(l) = nil;
	qunlock(q);
}

void*
libqlalloc(void)
{
	QLock *q;

	q = mallocz(sizeof(QLock)+sizeof(Prog*), 1);
	return q;
}

void
libqlfree(void *l)
{
	free(l);
}

vlong
libseek(int fd, vlong off, int whence)
{
	release();
	off = kseek(fd, off, whence);
	acquire();
	return off;
}

int
libread(int fd, void *buf, int n)
{
	release();
	n = kread(fd, buf, n);
	acquire();
	return n;
}

int
libreadn(int fd, void *av, long n)
{
	char *a;
	long m, t;

	a = av;
	t = 0;
	release();
	while(t < n){
		m = kread(fd, a+t, n-t);
		if(m <= 0){
			if(t == 0){
				acquire();
				return m;
			}
			break;
		}
		t += m;
	}
	acquire();
	return t;
}

int
libwrite(int fd, void *buf, int n)
{
	release();
	n = kwrite(fd, buf, n);
	acquire();
	return n;
}

int
libopen(char *name, int omode)
{
	int fd;

	release();
	fd = kopen(name, omode);
	acquire();
	return fd;
}

int
libclose(int fd)
{
	release();
	fd = kclose(fd);
	acquire();
	return fd;
}

Dir*
libdirfstat(int fd)
{
	Dir *d;

	release();
	d = kdirfstat(fd);
	acquire();
	return d;
}

int
libbind(char *s, char *t, int f)
{
	int n;

	release();
	n = kbind(s, t, f);
	acquire();
	return n;
}

void
libchanclose(void *chan)
{
	release();
	cclose(chan);
	acquire();
}

void*
libfdtochan(int fd, int mode)
{
	Chan *c;

	release();
	if(waserror()) {
		acquire();
		return nil;
	}
	c = fdtochan(up->env->fgrp, fd, mode, 0, 1);
	poperror();
	acquire();
	return c;
}