/*
 * jcomapi.c
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1994-1997, Thomas G. Lane.
 * It was modified by The libjpeg-turbo Project to include only code relevant
 * to libjpeg-turbo.
 * For conditions of distribution and use, see the accompanying README.ijg
 * 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;

	/* Do nothing if called on a not-initialized or destroyed JPEG object. */
	if (cinfo->mem == NULL)
		return;

	/* 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 */
	if (cinfo->is_decompressor) {
		cinfo->global_state = DSTATE_START;
		/* Try to keep application from accessing now-deleted marker list.
		 * A bit kludgy to do it here, but this is the most central place.
		 */
		((j_decompress_ptr) cinfo)->marker_list = NULL;
	} else {
		cinfo->global_state = 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;
}
