/*

 * Amanda, The Advanced Maryland Automatic Network Disk Archiver

 * Copyright (c) 2008-2012 Zmanda, Inc.  All Rights Reserved.

 * Copyright (c) 2013-2016 Carbonite, Inc.  All Rights Reserved.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * for more details.

 *

 * You should have received a copy of the GNU General Public License along

 * with this program; if not, write to the Free Software Foundation, Inc.,

 * 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA

 *

 * Contact information: Carbonite Inc., 756 N Pastoria Ave

 * Sunnyvale, CA 94085, or: http://www.zmanda.com

 */

#include "amanda.h"

#include "amxfer.h"

#include "simpleprng.h"

/*

 * Class declaration

 *

 * This declaration is entirely private; nothing but xfer_dest_null() references

 * it directly.

 */

GType xfer_dest_null_get_type(void);

#define XFER_DEST_NULL_TYPE (xfer_dest_null_get_type())

#define XFER_DEST_NULL(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_dest_null_get_type(), XferDestNull)

#define XFER_DEST_NULL_CONST(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_dest_null_get_type(), XferDestNull const)

#define XFER_DEST_NULL_CLASS(klass) G_TYPE_CHECK_CLASS_CAST((klass), xfer_dest_null_get_type(), XferDestNullClass)

#define IS_XFER_DEST_NULL(obj) G_TYPE_CHECK_INSTANCE_TYPE((obj), xfer_dest_null_get_type ())

#define XFER_DEST_NULL_GET_CLASS(obj) G_TYPE_INSTANCE_GET_CLASS((obj), xfer_dest_null_get_type(), XferDestNullClass)

static GObjectClass *parent_class = NULL;

/*

 * Main object structure

 */

typedef struct XferDestNull {

    XferElement __parent__;

    gboolean sent_info;

    gboolean do_verify;

    simpleprng_state_t prng;

    guint64 byte_position;

} XferDestNull;

/*

 * Class definition

 */

typedef struct {

    XferElementClass __parent__;

} XferDestNullClass;

/*

 * Implementation

 */

static void

push_buffer_impl(

    XferElement *elt,

    gpointer buf,

    size_t len)

{

    XferDestNull *self = (XferDestNull *)elt;

    if (buf) {

	crc32_add(buf, len, &elt->crc);

    } else {

	XMsg *msg = xmsg_new((XferElement *)self, XMSG_CRC, 0);

	msg->crc = crc32_finish(&elt->crc);

	msg->size = elt->crc.size;

	xfer_queue_message(XFER_ELEMENT(self)->xfer, msg);

	return;

    }

    if (self->do_verify && !elt->cancelled) {

	if (!simpleprng_verify_buffer(&self->prng, buf, len)) {

	    xfer_cancel_with_error(elt,

		"verification of incoming bytestream failed; see stderr for details"),

	    wait_until_xfer_cancelled(elt->xfer);

	    amfree(buf);

	    return;

	}

    }

    self->byte_position += len;

    if (!self->sent_info) {

	/* send a superfluous message (this is a testing XferElement,

	 * after all) */

	XMsg *msg = xmsg_new((XferElement *)self, XMSG_INFO, 0);

	msg->message = g_strdup("Is this thing on?");

	xfer_queue_message(XFER_ELEMENT(self)->xfer, msg);

	self->sent_info = TRUE;

    }

    amfree(buf);

}

static void

push_buffer_static_impl(

    XferElement *elt,

    gpointer buf,

    size_t len)

{

    XferDestNull *self = (XferDestNull *)elt;

    if (buf && len != 0) {

	crc32_add(buf, len, &elt->crc);

    } else {

	XMsg *msg = xmsg_new((XferElement *)self, XMSG_CRC, 0);

	msg->crc = crc32_finish(&elt->crc);

	msg->size = elt->crc.size;

	xfer_queue_message(XFER_ELEMENT(self)->xfer, msg);

	return;

    }

    if (self->do_verify && !elt->cancelled) {

	if (!simpleprng_verify_buffer(&self->prng, buf, len)) {

	    xfer_cancel_with_error(elt,

		"verification of incoming bytestream failed; see stderr for details"),

	    wait_until_xfer_cancelled(elt->xfer);

	    return;

	}

    }

    self->byte_position += len;

    if (!self->sent_info) {

	/* send a superfluous message (this is a testing XferElement,

	 * after all) */

	XMsg *msg = xmsg_new((XferElement *)self, XMSG_INFO, 0);

	msg->message = g_strdup("Is this thing on?");

	xfer_queue_message(XFER_ELEMENT(self)->xfer, msg);

	self->sent_info = TRUE;

    }

}

static void

class_init(

    XferDestNullClass * selfc)

{

    XferElementClass *klass = XFER_ELEMENT_CLASS(selfc);

    static xfer_element_mech_pair_t mech_pairs[] = {

	{ XFER_MECH_PUSH_BUFFER, XFER_MECH_NONE, XFER_NROPS(0), XFER_NTHREADS(0), XFER_NALLOC(0) },

	{ XFER_MECH_PUSH_BUFFER_STATIC, XFER_MECH_NONE, XFER_NROPS(0), XFER_NTHREADS(0), XFER_NALLOC(0) },

	{ XFER_MECH_NONE, XFER_MECH_NONE, XFER_NROPS(0), XFER_NTHREADS(0), XFER_NALLOC(0) },

    };

    klass->push_buffer = push_buffer_impl;

    klass->push_buffer_static = push_buffer_static_impl;

    klass->perl_class = "Amanda::Xfer::Dest::Null";

    klass->mech_pairs = mech_pairs;

    parent_class = g_type_class_peek_parent(selfc);

}

GType

xfer_dest_null_get_type (void)

{

    static GType type = 0;

    if (G_UNLIKELY(type == 0)) {

        static const GTypeInfo info = {

            sizeof (XferDestNullClass),

            (GBaseInitFunc) NULL,

            (GBaseFinalizeFunc) NULL,

            (GClassInitFunc) class_init,

            (GClassFinalizeFunc) NULL,

            NULL /* class_data */,

            sizeof (XferDestNull),

            0 /* n_preallocs */,

            (GInstanceInitFunc) NULL,

            NULL

        };

        type = g_type_register_static (XFER_ELEMENT_TYPE, "XferDestNull", &info, 0);

    }

    return type;

}

/* create an element of this class; prototype is in xfer-element.h */

XferElement *

xfer_dest_null(

    guint32 prng_seed)

{

    XferDestNull *self = (XferDestNull *)g_object_new(XFER_DEST_NULL_TYPE, NULL);

    XferElement *elt = XFER_ELEMENT(self);

    if (prng_seed) {

	self->do_verify = TRUE;

	simpleprng_seed(&self->prng, prng_seed);

    } else {

	self->do_verify = FALSE;

    }

    crc32_init(&elt->crc);

    return elt;

}