nuclear@26: /*
nuclear@26:  * jcomapi.c
nuclear@26:  *
nuclear@26:  * Copyright (C) 1994-1997, Thomas G. Lane.
nuclear@26:  * This file is part of the Independent JPEG Group's software.
nuclear@26:  * For conditions of distribution and use, see the accompanying README file.
nuclear@26:  *
nuclear@26:  * This file contains application interface routines that are used for both
nuclear@26:  * compression and decompression.
nuclear@26:  */
nuclear@26: 
nuclear@26: #define JPEG_INTERNALS
nuclear@26: #include "jinclude.h"
nuclear@26: #include "jpeglib.h"
nuclear@26: 
nuclear@26: 
nuclear@26: /*
nuclear@26:  * Abort processing of a JPEG compression or decompression operation,
nuclear@26:  * but don't destroy the object itself.
nuclear@26:  *
nuclear@26:  * For this, we merely clean up all the nonpermanent memory pools.
nuclear@26:  * Note that temp files (virtual arrays) are not allowed to belong to
nuclear@26:  * the permanent pool, so we will be able to close all temp files here.
nuclear@26:  * Closing a data source or destination, if necessary, is the application's
nuclear@26:  * responsibility.
nuclear@26:  */
nuclear@26: 
nuclear@26: GLOBAL(void)
nuclear@26: jpeg_abort (j_common_ptr cinfo)
nuclear@26: {
nuclear@26:   int pool;
nuclear@26: 
nuclear@26:   /* Do nothing if called on a not-initialized or destroyed JPEG object. */
nuclear@26:   if (cinfo->mem == NULL)
nuclear@26:     return;
nuclear@26: 
nuclear@26:   /* Releasing pools in reverse order might help avoid fragmentation
nuclear@26:    * with some (brain-damaged) malloc libraries.
nuclear@26:    */
nuclear@26:   for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
nuclear@26:     (*cinfo->mem->free_pool) (cinfo, pool);
nuclear@26:   }
nuclear@26: 
nuclear@26:   /* Reset overall state for possible reuse of object */
nuclear@26:   if (cinfo->is_decompressor) {
nuclear@26:     cinfo->global_state = DSTATE_START;
nuclear@26:     /* Try to keep application from accessing now-deleted marker list.
nuclear@26:      * A bit kludgy to do it here, but this is the most central place.
nuclear@26:      */
nuclear@26:     ((j_decompress_ptr) cinfo)->marker_list = NULL;
nuclear@26:   } else {
nuclear@26:     cinfo->global_state = CSTATE_START;
nuclear@26:   }
nuclear@26: }
nuclear@26: 
nuclear@26: 
nuclear@26: /*
nuclear@26:  * Destruction of a JPEG object.
nuclear@26:  *
nuclear@26:  * Everything gets deallocated except the master jpeg_compress_struct itself
nuclear@26:  * and the error manager struct.  Both of these are supplied by the application
nuclear@26:  * and must be freed, if necessary, by the application.  (Often they are on
nuclear@26:  * the stack and so don't need to be freed anyway.)
nuclear@26:  * Closing a data source or destination, if necessary, is the application's
nuclear@26:  * responsibility.
nuclear@26:  */
nuclear@26: 
nuclear@26: GLOBAL(void)
nuclear@26: jpeg_destroy (j_common_ptr cinfo)
nuclear@26: {
nuclear@26:   /* We need only tell the memory manager to release everything. */
nuclear@26:   /* NB: mem pointer is NULL if memory mgr failed to initialize. */
nuclear@26:   if (cinfo->mem != NULL)
nuclear@26:     (*cinfo->mem->self_destruct) (cinfo);
nuclear@26:   cinfo->mem = NULL;		/* be safe if jpeg_destroy is called twice */
nuclear@26:   cinfo->global_state = 0;	/* mark it destroyed */
nuclear@26: }
nuclear@26: 
nuclear@26: 
nuclear@26: /*
nuclear@26:  * Convenience routines for allocating quantization and Huffman tables.
nuclear@26:  * (Would jutils.c be a more reasonable place to put these?)
nuclear@26:  */
nuclear@26: 
nuclear@26: GLOBAL(JQUANT_TBL *)
nuclear@26: jpeg_alloc_quant_table (j_common_ptr cinfo)
nuclear@26: {
nuclear@26:   JQUANT_TBL *tbl;
nuclear@26: 
nuclear@26:   tbl = (JQUANT_TBL *)
nuclear@26:     (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
nuclear@26:   tbl->sent_table = FALSE;	/* make sure this is false in any new table */
nuclear@26:   return tbl;
nuclear@26: }
nuclear@26: 
nuclear@26: 
nuclear@26: GLOBAL(JHUFF_TBL *)
nuclear@26: jpeg_alloc_huff_table (j_common_ptr cinfo)
nuclear@26: {
nuclear@26:   JHUFF_TBL *tbl;
nuclear@26: 
nuclear@26:   tbl = (JHUFF_TBL *)
nuclear@26:     (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
nuclear@26:   tbl->sent_table = FALSE;	/* make sure this is false in any new table */
nuclear@26:   return tbl;
nuclear@26: }