/* Copyright (C) 1997 Aladdin Enterprises.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
  or distributor accepts any responsibility for the consequences of using it,
  or for whether it serves any particular purpose or works at all, unless he
  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
  normally in a plain ASCII text file named PUBLIC.  The License grants you
  the right to copy, modify and redistribute Aladdin Ghostscript, but only
  under certain conditions described in the License.  Among other things, the
  License requires that the copyright notice and this notice be preserved on
  all copies.
*/

/* icontext.c */
/* Context state operations */
#include "ghost.h"
#include "gsstruct.h"		/* for gxalloc.h */
#include "gxalloc.h"
#include "errors.h"
#include "igstate.h"
#include "icontext.h"
#include "interp.h"
#include "dstack.h"
#include "estack.h"
#include "ostack.h"
#include "store.h"

/* Define the initial stack sizes. */
#define DSTACK_INITIAL 20
#define ESTACK_INITIAL 250
#define OSTACK_INITIAL 200

/* Per-context state stored in statics */
extern ref ref_array_packing;
extern ref ref_binary_object_format;
extern ref user_names;
extern long zrand_state;

/* Initialization procedures */
void zrand_state_init(P1(long *));

/* Allocate the state of a context. */
/* The client is responsible for the 'memory' member. */
int
context_state_alloc(gs_context_state_t *pcst, gs_ref_memory_t *mem)
{	int code = gs_interp_create_stacks(mem, &pcst->dstack, &pcst->estack,
					   &pcst->ostack);

	if ( code < 0 )
	  return code;
	pcst->pgs = int_gstate_alloc(mem);
	if ( pcst->pgs == 0 )
	  return_error(e_VMerror);
	make_false(&pcst->array_packing);
	make_int(&pcst->binary_object_format, 0);
	zrand_state_init(&pcst->rand_state);
	pcst->usertime_total = 0;
	pcst->keep_usertime = false;
	/****** user parameters ******/
	/****** %stdin, %stdout ******/
	return 0;
}

/* Load the interpreter state from a context. */
void
context_state_load(const gs_context_state_t *pcst)
{	d_stack = *r_ptr(&pcst->dstack, ref_stack);
	e_stack = *r_ptr(&pcst->estack, ref_stack);
	o_stack = *r_ptr(&pcst->ostack, ref_stack);
	igs = pcst->pgs;
	gs_imemory = pcst->memory;
	ref_array_packing = pcst->array_packing;
	ref_binary_object_format = pcst->binary_object_format;
	zrand_state = pcst->rand_state;
	/****** user parameters ******/
	/****** %stdin, %stdout ******/
}

/* Store the interpreter state in a context. */
void
context_state_store(gs_context_state_t *pcst)
{	*r_ptr(&pcst->dstack, ref_stack) = d_stack;
	*r_ptr(&pcst->estack, ref_stack) = e_stack;
	*r_ptr(&pcst->ostack, ref_stack) = o_stack;
	pcst->pgs = igs;
	pcst->memory = gs_imemory;
	pcst->array_packing = ref_array_packing;
	pcst->binary_object_format = ref_binary_object_format;
	pcst->rand_state = zrand_state;
	/****** user parameters ******/
	/****** %stdin, %stdout ******/
}

/* Free the state of a context. */
void
context_state_free(gs_context_state_t *pcst, gs_ref_memory_t *mem)
{	/****** SEE alloc ABOVE ******/
	int i;

	/*
	 * If this context is the last one referencing a particular VM
	 * (local, or local and global), free the entire VM space;
	 * otherwise, just free the context-related structures.
	 */
	for ( i = countof(pcst->memory.spaces.indexed); --i >= 0; ) {
	  if ( pcst->memory.spaces.indexed[i] != 0 &&
	       !--(pcst->memory.spaces.indexed[i]->num_contexts)
	     ) {
	    /****** FREE THE ENTIRE SPACE ******/
	  }
	}
}