ccmsg.c

Go to the documentation of this file.

/*
 * Portions Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (C) 2001  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and/or 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 AND NOMINUM 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.
 *
 * Portions Copyright (C) 2001  Nominum, Inc.
 *
 * Permission to use, copy, modify, and/or 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 AND NOMINUM 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.
 */

/* $Id: ccmsg.c,v 1.10 2007/08/28 07:20:43 tbox Exp $ */

/*! \file */

#include <config.h>

#include <isc/mem.h>
#include <isc/result.h>
#include <isc/task.h>
#include <isc/util.h>

#include <isccc/events.h>
#include <isccc/ccmsg.h>

#define CCMSG_MAGIC             ISC_MAGIC('C', 'C', 'm', 's')
#define VALID_CCMSG(foo)        ISC_MAGIC_VALID(foo, CCMSG_MAGIC)

static void recv_length(isc_task_t *, isc_event_t *);
static void recv_message(isc_task_t *, isc_event_t *);


static void
recv_length(isc_task_t *task, isc_event_t *ev_in) {
        isc_socketevent_t *ev = (isc_socketevent_t *)ev_in;
        isc_event_t *dev;
        isccc_ccmsg_t *ccmsg = ev_in->ev_arg;
        isc_region_t region;
        isc_result_t result;

        INSIST(VALID_CCMSG(ccmsg));

        dev = &ccmsg->event;

        if (ev->result != ISC_R_SUCCESS) {
                ccmsg->result = ev->result;
                goto send_and_free;
        }

        /*
         * Success.
         */
        ccmsg->size = ntohl(ccmsg->size);
        if (ccmsg->size == 0) {
                ccmsg->result = ISC_R_UNEXPECTEDEND;
                goto send_and_free;
        }
        if (ccmsg->size > ccmsg->maxsize) {
                ccmsg->result = ISC_R_RANGE;
                goto send_and_free;
        }

        region.base = isc_mem_get(ccmsg->mctx, ccmsg->size);
        region.length = ccmsg->size;
        if (region.base == NULL) {
                ccmsg->result = ISC_R_NOMEMORY;
                goto send_and_free;
        }

        isc_buffer_init(&ccmsg->buffer, region.base, region.length);
        result = isc_socket_recv(ccmsg->sock, &region, 0,
                                 task, recv_message, ccmsg);
        if (result != ISC_R_SUCCESS) {
                ccmsg->result = result;
                goto send_and_free;
        }

        isc_event_free(&ev_in);
        return;

 send_and_free:
        isc_task_send(ccmsg->task, &dev);
        ccmsg->task = NULL;
        isc_event_free(&ev_in);
        return;
}

static void
recv_message(isc_task_t *task, isc_event_t *ev_in) {
        isc_socketevent_t *ev = (isc_socketevent_t *)ev_in;
        isc_event_t *dev;
        isccc_ccmsg_t *ccmsg = ev_in->ev_arg;

        (void)task;

        INSIST(VALID_CCMSG(ccmsg));

        dev = &ccmsg->event;

        if (ev->result != ISC_R_SUCCESS) {
                ccmsg->result = ev->result;
                goto send_and_free;
        }

        ccmsg->result = ISC_R_SUCCESS;
        isc_buffer_add(&ccmsg->buffer, ev->n);
        ccmsg->address = ev->address;

 send_and_free:
        isc_task_send(ccmsg->task, &dev);
        ccmsg->task = NULL;
        isc_event_free(&ev_in);
}

void
isccc_ccmsg_init(isc_mem_t *mctx, isc_socket_t *sock, isccc_ccmsg_t *ccmsg) {
        REQUIRE(mctx != NULL);
        REQUIRE(sock != NULL);
        REQUIRE(ccmsg != NULL);

        ccmsg->magic = CCMSG_MAGIC;
        ccmsg->size = 0;
        ccmsg->buffer.base = NULL;
        ccmsg->buffer.length = 0;
        ccmsg->maxsize = 4294967295U;   /* Largest message possible. */
        ccmsg->mctx = mctx;
        ccmsg->sock = sock;
        ccmsg->task = NULL;                     /* None yet. */
        ccmsg->result = ISC_R_UNEXPECTED;       /* None yet. */
        /*
         * Should probably initialize the event here, but it can wait.
         */
}


void
isccc_ccmsg_setmaxsize(isccc_ccmsg_t *ccmsg, unsigned int maxsize) {
        REQUIRE(VALID_CCMSG(ccmsg));

        ccmsg->maxsize = maxsize;
}


isc_result_t
isccc_ccmsg_readmessage(isccc_ccmsg_t *ccmsg,
                       isc_task_t *task, isc_taskaction_t action, void *arg)
{
        isc_result_t result;
        isc_region_t region;

        REQUIRE(VALID_CCMSG(ccmsg));
        REQUIRE(task != NULL);
        REQUIRE(ccmsg->task == NULL);  /* not currently in use */

        if (ccmsg->buffer.base != NULL) {
                isc_mem_put(ccmsg->mctx, ccmsg->buffer.base,
                            ccmsg->buffer.length);
                ccmsg->buffer.base = NULL;
                ccmsg->buffer.length = 0;
        }

        ccmsg->task = task;
        ccmsg->action = action;
        ccmsg->arg = arg;
        ccmsg->result = ISC_R_UNEXPECTED;  /* unknown right now */

        ISC_EVENT_INIT(&ccmsg->event, sizeof(isc_event_t), 0, 0,
                       ISCCC_EVENT_CCMSG, action, arg, ccmsg,
                       NULL, NULL);

        region.base = (unsigned char *)&ccmsg->size;
        region.length = 4;  /* isc_uint32_t */
        result = isc_socket_recv(ccmsg->sock, &region, 0,
                                 ccmsg->task, recv_length, ccmsg);

        if (result != ISC_R_SUCCESS)
                ccmsg->task = NULL;

        return (result);
}

void
isccc_ccmsg_cancelread(isccc_ccmsg_t *ccmsg) {
        REQUIRE(VALID_CCMSG(ccmsg));

        isc_socket_cancel(ccmsg->sock, NULL, ISC_SOCKCANCEL_RECV);
}

#if 0
void
isccc_ccmsg_freebuffer(isccc_ccmsg_t *ccmsg) {
        REQUIRE(VALID_CCMSG(ccmsg));

        if (ccmsg->buffer.base == NULL)
                return;

        isc_mem_put(ccmsg->mctx, ccmsg->buffer.base, ccmsg->buffer.length);
        ccmsg->buffer.base = NULL;
        ccmsg->buffer.length = 0;
}
#endif

void
isccc_ccmsg_invalidate(isccc_ccmsg_t *ccmsg) {
        REQUIRE(VALID_CCMSG(ccmsg));

        ccmsg->magic = 0;

        if (ccmsg->buffer.base != NULL) {
                isc_mem_put(ccmsg->mctx, ccmsg->buffer.base,
                            ccmsg->buffer.length);
                ccmsg->buffer.base = NULL;
                ccmsg->buffer.length = 0;
        }
}

---