/*

 * 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: Zmanda Inc., 465 N Mathlida Ave, Suite 300

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

 */

#include "amanda.h"

#include "amxfer.h"

/*

 * Class declaration

 *

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

 * it directly.

 */

GType xfer_dest_buffer_get_type(void);

#define XFER_DEST_BUFFER_TYPE (xfer_dest_buffer_get_type())

#define XFER_DEST_BUFFER(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_dest_buffer_get_type(), XferDestBuffer)

#define XFER_DEST_BUFFER_CONST(obj) G_TYPE_CHECK_INSTANCE_CAST((obj), xfer_dest_buffer_get_type(), XferDestBuffer const)

#define XFER_DEST_BUFFER_CLASS(klass) G_TYPE_CHECK_CLASS_CAST((klass), xfer_dest_buffer_get_type(), XferDestBufferClass)

#define IS_XFER_DEST_BUFFER(obj) G_TYPE_CHECK_INSTANCE_TYPE((obj), xfer_dest_buffer_get_type ())

#define XFER_DEST_BUFFER_GET_CLASS(obj) G_TYPE_INSTANCE_GET_CLASS((obj), xfer_dest_buffer_get_type(), XferDestBufferClass)

static GObjectClass *parent_class = NULL;

/*

 * Main object structure

 */

typedef struct XferDestBuffer {

    XferElement __parent__;

    gsize max_size;

    gpointer buf;

    gsize len;

    gsize allocated;

} XferDestBuffer;

/*

 * Class definition

 */

typedef struct {

    XferElementClass __parent__;

    void (*get)(XferDestBuffer *self, gpointer *buf, gsize *size);

} XferDestBufferClass;

/*

 * Implementation

 */

static void

get_impl(

    XferDestBuffer *self,

    gpointer *buf,

    gsize *size)

{

    if (size)

	*size = self->len;

    if (buf)

	*buf = self->buf;

}

static void

push_buffer_impl(

    XferElement *elt,

    gpointer buf,

    size_t len)

{

    XferDestBuffer *self = (XferDestBuffer *)elt;

    if (!buf)

	return;

    /* make sure this isn't too much data */

    if (self->max_size && self->len + len > self->max_size) {

	xfer_cancel_with_error(elt,

	    _("illegal attempt to transfer more than %zd bytes"), self->max_size);

	wait_until_xfer_cancelled(elt->xfer);

	amfree(buf);

	return;

    }

    /* expand the buffer if necessary */

    if (self->len + len > self->allocated) {

	gsize new_size = self->allocated * 2;

	if (new_size < self->len+len)

	    new_size = self->len+len;

	if (self->max_size && new_size > self->max_size)

	    new_size = self->max_size;

	self->buf = g_realloc(self->buf, new_size);

	self->allocated = new_size;

    }

    g_memmove(((guint8 *)self->buf)+self->len, buf, len);

    self->len += len;

    amfree(buf);

}

static void

push_buffer_static_impl(

    XferElement *elt,

    gpointer buf,

    size_t len)

{

    XferDestBuffer *self = (XferDestBuffer *)elt;

    if (!buf || len == 0)

	return;

    /* make sure this isn't too much data */

    if (self->max_size && self->len + len > self->max_size) {

	xfer_cancel_with_error(elt,

	    _("illegal attempt to transfer more than %zd bytes"), self->max_size);

	wait_until_xfer_cancelled(elt->xfer);

	return;

    }

    /* expand the buffer if necessary */

    if (self->len + len > self->allocated) {

	gsize new_size = self->allocated * 2;

	if (new_size < self->len+len)

	    new_size = self->len+len;

	if (self->max_size && new_size > self->max_size)

	    new_size = self->max_size;

	self->buf = g_realloc(self->buf, new_size);

	self->allocated = new_size;

    }

    g_memmove(((guint8 *)self->buf)+self->len, buf, len);

    self->len += len;

}

static void

finalize_impl(

    GObject * obj_self)

{

    XferDestBuffer *self = XFER_DEST_BUFFER(obj_self);

    if (self->buf)

	g_free(self->buf);

    self->buf = NULL;

    /* chain up */

    G_OBJECT_CLASS(parent_class)->finalize(obj_self);

}

static void

class_init(

    XferDestBufferClass * selfc)

{

    XferElementClass *klass = XFER_ELEMENT_CLASS(selfc);

    GObjectClass *goc = G_OBJECT_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) },

    };

    selfc->get = get_impl;

    klass->push_buffer = push_buffer_impl;

    klass->push_buffer_static = push_buffer_static_impl;

    goc->finalize = finalize_impl;

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

    klass->mech_pairs = mech_pairs;

    parent_class = g_type_class_peek_parent(selfc);

}

GType

xfer_dest_buffer_get_type (void)

{

    static GType type = 0;

    if (G_UNLIKELY(type == 0)) {

        static const GTypeInfo info = {

            sizeof (XferDestBufferClass),

            (GBaseInitFunc) NULL,

            (GBaseFinalizeFunc) NULL,

            (GClassInitFunc) class_init,

            (GClassFinalizeFunc) NULL,

            NULL /* class_data */,

            sizeof (XferDestBuffer),

            0 /* n_preallocs */,

            (GInstanceInitFunc) NULL,

            NULL

        };

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

    }

    return type;

}

void

xfer_dest_buffer_get(

    XferElement *elt,

    gpointer *buf,

    gsize *size)

{

    XferDestBufferClass *klass;

    g_assert(IS_XFER_DEST_BUFFER(elt));

    klass = XFER_DEST_BUFFER_GET_CLASS(elt);

    klass->get(XFER_DEST_BUFFER(elt), buf, size);

}

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

XferElement *

xfer_dest_buffer(

    gsize max_size)

{

    XferDestBuffer *self = (XferDestBuffer *)g_object_new(XFER_DEST_BUFFER_TYPE, NULL);

    XferElement *elt = XFER_ELEMENT(self);

    self->max_size = max_size;

    return elt;

}