137 lines
3.7 KiB
C
137 lines
3.7 KiB
C
/* $NetBSD: callcontext.c,v 1.3 2007/02/17 23:00:16 pooka Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 2006 Antti Kantee. All Rights Reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. The name of the company nor the name of the author may be used to
|
|
* endorse or promote products derived from this software without specific
|
|
* prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
|
|
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
#if !defined(lint)
|
|
__RCSID("$NetBSD: callcontext.c,v 1.3 2007/02/17 23:00:16 pooka Exp $");
|
|
#endif /* !lint */
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <assert.h>
|
|
#include <puffs.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <ucontext.h>
|
|
|
|
#include "puffs_priv.h"
|
|
|
|
/*
|
|
* user stuff
|
|
*/
|
|
|
|
void
|
|
puffs_cc_yield(struct puffs_cc *pcc)
|
|
{
|
|
|
|
assert((pcc->pcc_flags & PCC_DONE) == 0);
|
|
|
|
/* romanes eunt domus */
|
|
swapcontext(&pcc->pcc_uc, &pcc->pcc_uc_ret);
|
|
}
|
|
|
|
void
|
|
puffs_cc_continue(struct puffs_cc *pcc)
|
|
{
|
|
|
|
/* ramble on */
|
|
swapcontext(&pcc->pcc_uc_ret, &pcc->pcc_uc);
|
|
}
|
|
|
|
struct puffs_usermount *
|
|
puffs_cc_getusermount(struct puffs_cc *pcc)
|
|
{
|
|
|
|
return pcc->pcc_pu;
|
|
}
|
|
|
|
struct puffs_cc *
|
|
puffs_cc_create(struct puffs_usermount *pu)
|
|
{
|
|
struct puffs_cc *volatile pcc;
|
|
stack_t *st;
|
|
|
|
pcc = malloc(sizeof(struct puffs_cc));
|
|
if (!pcc)
|
|
return NULL;
|
|
memset(pcc, 0, sizeof(struct puffs_cc));
|
|
pcc->pcc_pu = pu;
|
|
pcc->pcc_priv = (void *)0xdeadbeef;
|
|
pcc->pcc_flags = PCC_REALCC;
|
|
|
|
/* initialize both ucontext's */
|
|
if (getcontext(&pcc->pcc_uc) == -1) {
|
|
free(pcc);
|
|
return NULL;
|
|
}
|
|
if (getcontext(&pcc->pcc_uc_ret) == -1) {
|
|
free(pcc);
|
|
return NULL;
|
|
}
|
|
/* return here. it won't actually be "here" due to swapcontext() */
|
|
pcc->pcc_uc.uc_link = &pcc->pcc_uc_ret;
|
|
|
|
/* allocate stack for execution */
|
|
st = &pcc->pcc_uc.uc_stack;
|
|
st->ss_sp = pcc->pcc_stack = malloc(pu->pu_cc_stacksize);
|
|
if (st->ss_sp == NULL) {
|
|
free(pcc);
|
|
return NULL;
|
|
}
|
|
st->ss_size = pu->pu_cc_stacksize;
|
|
st->ss_flags = 0;
|
|
|
|
/*
|
|
* Give us an initial context to jump to.
|
|
*
|
|
* XXX: Our manual page says that portable code shouldn't rely on
|
|
* being able to pass pointers through makecontext(). kjk says
|
|
* that NetBSD code doesn't need to worry about this. uwe says
|
|
* it would be like putting a "keep away from children" sign on a
|
|
* box of toys. I didn't ask what simon says; he's probably busy
|
|
* "fixing" typos in comments.
|
|
*/
|
|
makecontext(&pcc->pcc_uc, (void *)puffs_calldispatcher,
|
|
1, (uintptr_t)pcc);
|
|
|
|
return pcc;
|
|
}
|
|
|
|
void
|
|
puffs_cc_destroy(struct puffs_cc *pcc)
|
|
{
|
|
|
|
if (pcc->pcc_preq)
|
|
free(pcc->pcc_preq);
|
|
free(pcc->pcc_stack);
|
|
free(pcc);
|
|
}
|