/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996-1999 by Internet Software Consortium
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* ev_waits.c - implement deferred function calls for the eventlib
* vix 05dec95 [initial]
*/
#if !defined(LINT) && !defined(CODECENTER)
static const char rcsid[] = "$Id: ev_waits.c,v 1.4 2005/04/27 04:56:36 sra Exp $";
#endif
#include "port_before.h"
#include "fd_setsize.h"
#include <errno.h>
#include <isc/eventlib.h>
#include <isc/assertions.h>
#include "eventlib_p.h"
#include "port_after.h"
/* Forward. */
static void print_waits(evContext_p *ctx);
static evWaitList * evNewWaitList(evContext_p *);
static void evFreeWaitList(evContext_p *, evWaitList *);
static evWaitList * evGetWaitList(evContext_p *, const void *, int);
/* Public. */
/*%
* Enter a new wait function on the queue.
*/
int
evWaitFor(evContext opaqueCtx, const void *tag,
evWaitFunc func, void *uap, evWaitID *id)
{
evContext_p *ctx = opaqueCtx.opaque;
evWait *new;
evWaitList *wl = evGetWaitList(ctx, tag, 1);
OKNEW(new);
new->func = func;
new->uap = uap;
new->tag = tag;
new->next = NULL;
if (wl->last != NULL)
wl->last->next = new;
else
wl->first = new;
wl->last = new;
if (id != NULL)
id->opaque = new;
if (ctx->debug >= 9)
print_waits(ctx);
return (0);
}
/*%
* Mark runnable all waiting functions having a certain tag.
*/
int
evDo(evContext opaqueCtx, const void *tag) {
evContext_p *ctx = opaqueCtx.opaque;
evWaitList *wl = evGetWaitList(ctx, tag, 0);
evWait *first;
if (!wl) {
errno = ENOENT;
return (-1);
}
first = wl->first;
INSIST(first != NULL);
if (ctx->waitDone.last != NULL)
ctx->waitDone.last->next = first;
else
ctx->waitDone.first = first;
ctx->waitDone.last = wl->last;
evFreeWaitList(ctx, wl);
return (0);
}
/*%
* Remove a waiting (or ready to run) function from the queue.
*/
int
evUnwait(evContext opaqueCtx, evWaitID id) {
evContext_p *ctx = opaqueCtx.opaque;
evWait *this, *prev;
evWaitList *wl;
int found = 0;
this = id.opaque;
INSIST(this != NULL);
wl = evGetWaitList(ctx, this->tag, 0);
if (wl != NULL) {
for (prev = NULL, this = wl->first;
this != NULL;
prev = this, this = this->next)
if (this == (evWait *)id.opaque) {
found = 1;
if (prev != NULL)
prev->next = this->next;
else
wl->first = this->next;
if (wl->last == this)
wl->last = prev;
if (wl->first == NULL)
evFreeWaitList(ctx, wl);
break;
}
}
if (!found) {
/* Maybe it's done */
for (prev = NULL, this = ctx->waitDone.first;
this != NULL;
prev = this, this = this->next)
if (this == (evWait *)id.opaque) {
found = 1;
if (prev != NULL)
prev->next = this->next;
else
ctx->waitDone.first = this->next;
if (ctx->waitDone.last == this)
ctx->waitDone.last = prev;
break;
}
}
if (!found) {
errno = ENOENT;
return (-1);
}
FREE(this);
if (ctx->debug >= 9)
print_waits(ctx);
return (0);
}
int
evDefer(evContext opaqueCtx, evWaitFunc func, void *uap) {
evContext_p *ctx = opaqueCtx.opaque;
evWait *new;
OKNEW(new);
new->func = func;
new->uap = uap;
new->tag = NULL;
new->next = NULL;
if (ctx->waitDone.last != NULL)
ctx->waitDone.last->next = new;
else
ctx->waitDone.first = new;
ctx->waitDone.last = new;
if (ctx->debug >= 9)
print_waits(ctx);
return (0);
}
/* Private. */
static void
print_waits(evContext_p *ctx) {
evWaitList *wl;
evWait *this;
evPrintf(ctx, 9, "wait waiting:\n");
for (wl = ctx->waitLists; wl != NULL; wl = wl->next) {
INSIST(wl->first != NULL);
evPrintf(ctx, 9, " tag %p:", wl->first->tag);
for (this = wl->first; this != NULL; this = this->next)
evPrintf(ctx, 9, " %p", this);
evPrintf(ctx, 9, "\n");
}
evPrintf(ctx, 9, "wait done:");
for (this = ctx->waitDone.first; this != NULL; this = this->next)
evPrintf(ctx, 9, " %p", this);
evPrintf(ctx, 9, "\n");
}
static evWaitList *
evNewWaitList(evContext_p *ctx) {
evWaitList *new;
NEW(new);
if (new == NULL)
return (NULL);
new->first = new->last = NULL;
new->prev = NULL;
new->next = ctx->waitLists;
if (new->next != NULL)
new->next->prev = new;
ctx->waitLists = new;
return (new);
}
static void
evFreeWaitList(evContext_p *ctx, evWaitList *this) {
INSIST(this != NULL);
if (this->prev != NULL)
this->prev->next = this->next;
else
ctx->waitLists = this->next;
if (this->next != NULL)
this->next->prev = this->prev;
FREE(this);
}
static evWaitList *
evGetWaitList(evContext_p *ctx, const void *tag, int should_create) {
evWaitList *this;
for (this = ctx->waitLists; this != NULL; this = this->next) {
if (this->first != NULL && this->first->tag == tag)
break;
}
if (this == NULL && should_create)
this = evNewWaitList(ctx);
return (this);
}
/*! \file */