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/*$Id: ireclaim.c,v 1.6 1999/05/30 18:58:32 masata-y Exp $ */
/* Interpreter's interface to garbage collector */
#include "ghost.h"
#include "errors.h"
#include "gsstruct.h"
#include "iastate.h"
#include "icontext.h"
#include "interp.h"
#include "isave.h"		/* for isstate.h */
#include "isstate.h"		/* for mem->saved->state */
#include "dstack.h"		/* for dsbot, dsp, dict_set_top */
#include "estack.h"		/* for esbot, esp */
#include "ostack.h"		/* for osbot, osp */
#include "opdef.h"		/* for defining init procedure */
#include "store.h"		/* for make_array */

/* Import preparation and cleanup routines. */
extern void ialloc_gc_prepare(P1(gs_ref_memory_t *));

/* Forward references */
private void gs_vmreclaim(P2(gs_dual_memory_t *, bool));

/* Initialize the GC hook in the allocator. */
private int ireclaim(P2(gs_dual_memory_t *, int));
private void
ireclaim_init(void)
{
    gs_imemory.reclaim = ireclaim;
}

/* GC hook called when the allocator returns a VMerror (space = -1), */
/* or for vmreclaim (space = the space to collect). */
private int
ireclaim(gs_dual_memory_t * dmem, int space)
{
    bool global;
    gs_ref_memory_t *mem;

/****** HACK ******/
    /* return 0;  */
    /* this statement turns of garbage collector. */
    if (space < 0) {		/* Determine which allocator got the VMerror. */
	gs_memory_status_t stats;
	int i;

	mem = dmem->space_global;	/* just in case */
	for (i = 0; i < countof(dmem->spaces.indexed); ++i) {
	    mem = dmem->spaces.indexed[i];
	    if (mem == 0)
		continue;
	    if (mem->gc_status.requested > 0)
		break;
	}
	gs_memory_status((gs_memory_t *) mem, &stats);
	if (stats.allocated >= mem->gc_status.max_vm) {		/* We can't satisfy this request within max_vm. */
	    return_error(e_VMerror);
	}
    } else {
	mem = dmem->spaces.indexed[space >> r_space_shift];
    }
    if_debug3('0', "[0]GC called, space=%d, requestor=%d, requested=%ld\n",
	      space, mem->space, (long)mem->gc_status.requested);
    global = mem->space != avm_local;
    gs_vmreclaim(dmem, global);

    ialloc_set_limit(mem);
    ialloc_reset_requested(dmem);
    return 0;
}

/* Interpreter entry to garbage collector. */
private void
gs_vmreclaim(gs_dual_memory_t * dmem, bool global)
{
    gs_ref_memory_t *lmem = dmem->space_local;
    gs_ref_memory_t *gmem = dmem->space_global;
    gs_ref_memory_t *smem = dmem->space_system;
    int code = context_state_store(gs_interp_context_state_current);

/****** ABORT IF code < 0 ******/
    alloc_close_chunk(lmem);
    if (gmem != lmem)
	alloc_close_chunk(gmem);
    alloc_close_chunk(smem);

    /* Prune the file list so it won't retain potentially collectible */
    /* files. */

    {
	int i;

	for (i = (global ? i_vm_system : i_vm_local);
	     i < countof(dmem->spaces.indexed);
	     ++i
	    ) {
	    gs_ref_memory_t *mem = dmem->spaces.indexed[i];

	    if (mem == 0 || (i > 0 && mem == dmem->spaces.indexed[i - 1]))
		continue;
	    for (;; mem = &mem->saved->state) {
		ialloc_gc_prepare(mem);
		if (mem->saved == 0)
		    break;
	    }
	}
    }

    /* Do the actual collection. */

    gs_reclaim(&dmem->spaces, global);

    /* Reload the context state. */

    code = context_state_load(gs_interp_context_state_current);
/****** ABORT IF code < 0 ******/

    /* Update the cached value pointers in names. */

    dicts_gc_cleanup();

    /* Reopen the active chunks. */

    alloc_open_chunk(smem);
    if (gmem != lmem)
	alloc_open_chunk(gmem);
    alloc_open_chunk(lmem);

    /* Update caches not handled by context_state_load. */

    {
	uint dcount = ref_stack_count(&d_stack);

	*systemdict = *ref_stack_index(&d_stack, dcount - 1);
    }
}

/* ------ Initialization procedure ------ */

const op_def ireclaim_l2_op_defs[] =
{
    op_def_end(ireclaim_init)
};
