src/data_buffer.cc

/*
	Copyright (c) 2012-2014, Santeri Piippo
	All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions are met:

		* Redistributions of source code must retain the above copyright
		  notice, this list of conditions and the following disclaimer.

		* 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.

		* Neither the name of the <organization> nor the
		  names of its contributors may be used to endorse or promote products
		  derived from this software without specific prior written permission.

	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 <COPYRIGHT HOLDER> 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 "data_buffer.h"

// ============================================================================
//
void data_buffer::merge (data_buffer* other)
{
	if (!other)
		return;

	int oldsize = writesize;

	for (int x = 0; x < other->writesize; x++)
		write (* (other->buffer + x));

	// Merge its marks and references
	int u = 0;

	for (u = 0; u < MAX_MARKS; u++)
	{
		if (other->marks[u])
		{
			// Merge the mark and offset its position.
			if (marks[u])
				error ("DataBuffer: duplicate mark %d!\n");

			marks[u] = other->marks[u];
			marks[u]->pos += oldsize;

			// The original mark becomes null so that the deconstructor
			// will not delete it prematurely. (should it delete any
			// marks in the first place since there is no such thing
			// as at temporary mark?)
			other->marks[u] = null;
		}

		if (other->refs[u])
		{
			// Same for references
			// TODO: add a g_NextRef system like here, akin to marks!
			int r = add_reference (other->refs[u]->num, false);
			refs[r]->pos = other->refs[u]->pos + oldsize;
		}
	}

	delete other;
}

// ============================================================================
//
data_buffer* data_buffer::clone()
{
	data_buffer* other = new data_buffer;

	for (int x = 0; x < writesize; x++)
		other->write (* (buffer + x));

	return other;
}

// ============================================================================
//
int data_buffer::add_mark (string name)
{
	// Find a free slot for the mark
	int u = g_NextMark++;

	if (marks[u])
		error ("DataBuffer: attempted to re-create mark %u!\n", u);

	if (u >= MAX_MARKS)
		error ("mark quota exceeded, all labels, if-structs and loops add marks\n");

	ScriptMark* m = new ScriptMark;
	m->name = name;
	m->pos = writesize;
	marks[u] = m;
	return u;
}

// ============================================================================
//
int data_buffer::add_reference (int marknum, bool placeholder)
{
	int u;

	for (u = 0; u < MAX_MARKS; u++)
		if (!refs[u])
			break;

	// TODO: get rid of this
	if (u == MAX_MARKS)
		error ("mark reference quota exceeded, all goto-statements, if-structs and loops add refs\n");

	ScriptMarkReference* r = new ScriptMarkReference;
	r->num = marknum;
	r->pos = writesize;
	refs[u] = r;

	// Write a dummy placeholder for the reference
	if (placeholder)
		write (0xBEEFCAFE);

	return u;
}

// ============================================================================
//
void data_buffer::delete_mark (int marknum)
{
	if (!marks[marknum])
		return;

	// Delete the mark
	delete marks[marknum];
	marks[marknum] = null;

	// Delete its references
	for (int u = 0; u < MAX_MARKS; u++)
	{
		if (refs[u]->num == marknum)
		{
			delete refs[u];
			refs[u] = null;
		}
	}
}

// ============================================================================
//
void data_buffer::move_mark (int i)
{
	if (!marks[i])
		return;

	marks[i]->pos = writesize;
}

// ============================================================================
//
void data_buffer::offset_mark (int mark, int offset)
{
	if (!marks[mark])
		return;

	marks[mark]->pos += offset;
}

// ============================================================================
//
int data_buffer::count_marks()
{
	int count = 0;

	for (int u = 0; u < MAX_MARKS; u++)
		count += !!marks[u];

	return count;
}

// ============================================================================
//
int data_buffer::count_references()
{
	int count = 0;

	for (int u = 0; u < MAX_MARKS; u++)
		count += !!refs[u];

	return count;
}

// ============================================================================
//
void data_buffer::write_float (string floatstring)
{
	// TODO: Casting float to word causes the decimal to be lost.
	// Find a way to store the number without such loss.
	float val = atof (floatstring);
	write (dh_push_number);
	write (static_cast<word> (abs (val)));

	if (val < 0)
		write (dh_unary_minus);
}

// ============================================================================
//
void data_buffer::write_string (string a)
{
	write (dh_push_string_index);
	write (get_string_table_index (a));
}

// ============================================================================
//
void data_buffer::dump()
{
	for (int x = 0; x < writesize; x++)
		printf ("%d. [%d]\n", x, * (buffer + x));
}

// ============================================================================
//
data_buffer::~data_buffer()
{
	delete buffer;

	// Delete any marks and references
	for (int i = 0; i < MAX_MARKS; i++)
	{
		delete marks[i];
		delete refs[i];
	}
}

// ============================================================================
//
data_buffer::data_buffer (int size)
{
	writesize = 0;

	buffer = new unsigned char[size];
	allocsize = size;

	// Clear the marks table out
	for (int u = 0; u < MAX_MARKS; u++)
	{
		marks[u] = null;
		refs[u] = null;
	}
}