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Thomas G. Lane36a4ccc1994-09-24 00:00:00 +00001/*
2 * jcomapi.c
3 *
DRC5de454b2014-05-18 19:04:03 +00004 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1994-1997, Thomas G. Lane.0
6 * It was modified by The libjpeg-turbo Project to include only code relevant
7 * to libjpeg-turbo.
DRC7e3acc02015-10-10 10:25:46 -05008 * For conditions of distribution and use, see the accompanying README.ijg
9 * file.
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000010 *
11 * This file contains application interface routines that are used for both
12 * compression and decompression.
13 */
14
15#define JPEG_INTERNALS
16#include "jinclude.h"
17#include "jpeglib.h"
18
19
20/*
21 * Abort processing of a JPEG compression or decompression operation,
22 * but don't destroy the object itself.
23 *
24 * For this, we merely clean up all the nonpermanent memory pools.
25 * Note that temp files (virtual arrays) are not allowed to belong to
26 * the permanent pool, so we will be able to close all temp files here.
27 * Closing a data source or destination, if necessary, is the application's
28 * responsibility.
29 */
30
Thomas G. Lane489583f1996-02-07 00:00:00 +000031GLOBAL(void)
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000032jpeg_abort (j_common_ptr cinfo)
33{
34 int pool;
35
Thomas G. Lane5ead57a1998-03-27 00:00:00 +000036 /* Do nothing if called on a not-initialized or destroyed JPEG object. */
37 if (cinfo->mem == NULL)
38 return;
39
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000040 /* Releasing pools in reverse order might help avoid fragmentation
41 * with some (brain-damaged) malloc libraries.
42 */
43 for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
44 (*cinfo->mem->free_pool) (cinfo, pool);
45 }
46
47 /* Reset overall state for possible reuse of object */
Thomas G. Lane5ead57a1998-03-27 00:00:00 +000048 if (cinfo->is_decompressor) {
49 cinfo->global_state = DSTATE_START;
50 /* Try to keep application from accessing now-deleted marker list.
51 * A bit kludgy to do it here, but this is the most central place.
52 */
53 ((j_decompress_ptr) cinfo)->marker_list = NULL;
54 } else {
55 cinfo->global_state = CSTATE_START;
56 }
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000057}
58
59
60/*
61 * Destruction of a JPEG object.
62 *
63 * Everything gets deallocated except the master jpeg_compress_struct itself
64 * and the error manager struct. Both of these are supplied by the application
65 * and must be freed, if necessary, by the application. (Often they are on
66 * the stack and so don't need to be freed anyway.)
67 * Closing a data source or destination, if necessary, is the application's
68 * responsibility.
69 */
70
Thomas G. Lane489583f1996-02-07 00:00:00 +000071GLOBAL(void)
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000072jpeg_destroy (j_common_ptr cinfo)
73{
74 /* We need only tell the memory manager to release everything. */
75 /* NB: mem pointer is NULL if memory mgr failed to initialize. */
76 if (cinfo->mem != NULL)
77 (*cinfo->mem->self_destruct) (cinfo);
DRCe5eaf372014-05-09 18:00:32 +000078 cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */
79 cinfo->global_state = 0; /* mark it destroyed */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000080}
81
82
83/*
84 * Convenience routines for allocating quantization and Huffman tables.
85 * (Would jutils.c be a more reasonable place to put these?)
86 */
87
Thomas G. Lane489583f1996-02-07 00:00:00 +000088GLOBAL(JQUANT_TBL *)
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000089jpeg_alloc_quant_table (j_common_ptr cinfo)
90{
91 JQUANT_TBL *tbl;
92
93 tbl = (JQUANT_TBL *)
DRC5de454b2014-05-18 19:04:03 +000094 (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, sizeof(JQUANT_TBL));
DRCe5eaf372014-05-09 18:00:32 +000095 tbl->sent_table = FALSE; /* make sure this is false in any new table */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +000096 return tbl;
97}
98
99
Thomas G. Lane489583f1996-02-07 00:00:00 +0000100GLOBAL(JHUFF_TBL *)
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000101jpeg_alloc_huff_table (j_common_ptr cinfo)
102{
103 JHUFF_TBL *tbl;
104
105 tbl = (JHUFF_TBL *)
DRC5de454b2014-05-18 19:04:03 +0000106 (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, sizeof(JHUFF_TBL));
DRCe5eaf372014-05-09 18:00:32 +0000107 tbl->sent_table = FALSE; /* make sure this is false in any new table */
Thomas G. Lane36a4ccc1994-09-24 00:00:00 +0000108 return tbl;
109}