//  * jcomapi.c
//  *
//  * Copyright (C) 1994, Thomas G. Lane.
//  * This file is part of the Independent JPEG Group's software.
//  * For conditions of distribution and use, see the accompanying README file.
//  *
//  * This file contains application interface routines that are used for both
//  * compression and decompression.



#define JPEG_INTERNALS
#include "JINCLUDE.h"
#include "JPEGLIB.h"


//  * Abort processing of a JPEG compression or decompression operation,
//  * but don't destroy the object itself.
//  *
//  * For this, we merely clean up all the nonpermanent memory pools.
//  * Note that temp files (virtual arrays) are not allowed to belong to
//  * the permanent pool, so we will be able to close all temp files here.
//  * Closing a data source or destination, if necessary, is the application's
//  * responsibility.

GLOBAL void
jpeg_abort (j_common_ptr cinfo)
{
  int pool;

//  Releasing pools in reverse order might help avoid fragmentation
//    * with some (brain-damaged) malloc libraries.
  for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
    (*cinfo->mem->free_pool) (cinfo, pool);
  }

  // Reset overall state for possible reuse of object 
  cinfo->global_state = (cinfo->is_decompressor ? DSTATE_START : CSTATE_START);
}


//  * Destruction of a JPEG object.
//  *
//  * Everything gets deallocated except the master jpeg_compress_struct itself
//  * and the error manager struct.  Both of these are supplied by the application
//  * and must be freed, if necessary, by the application.  (Often they are on
//  * the stack and so don't need to be freed anyway.)
//  * Closing a data source or destination, if necessary, is the application's
//  * responsibility.

GLOBAL void
jpeg_destroy (j_common_ptr cinfo)
{
  // We need only tell the memory manager to release everything. 
  // NB: mem pointer is NULL if memory mgr failed to initialize. 
  if (cinfo->mem != NULL)
    (*cinfo->mem->self_destruct) (cinfo);
  cinfo->mem = NULL;		// be safe if jpeg_destroy is called twice 
  cinfo->global_state = 0;	// mark it destroyed 
}


//  * Convenience routines for allocating quantization and Huffman tables.
//  * (Would jutils.c be a more reasonable place to put these?)

GLOBAL JQUANT_TBL *
jpeg_alloc_quant_table (j_common_ptr cinfo)
{
  JQUANT_TBL *tbl;

  tbl = (JQUANT_TBL *)
    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
  tbl->sent_table = FALSE;	// make sure this is false in any new table 
  return tbl;
}


GLOBAL JHUFF_TBL *
jpeg_alloc_huff_table (j_common_ptr cinfo)
{
  JHUFF_TBL *tbl;

  tbl = (JHUFF_TBL *)
    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
  tbl->sent_table = FALSE;	// make sure this is false in any new table 
  return tbl;
}