ReactOS  0.4.14-dev-297-g23e575c
jcomapi.c
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1 /*
2  * jcomapi.c
3  *
4  * Copyright (C) 1994-1997, Thomas G. Lane.
5  * This file is part of the Independent JPEG Group's software.
6  * For conditions of distribution and use, see the accompanying README file.
7  *
8  * This file contains application interface routines that are used for both
9  * compression and decompression.
10  */
11 
12 #define JPEG_INTERNALS
13 #include "jinclude.h"
14 #include "jpeglib.h"
15 
16 
17 /*
18  * Abort processing of a JPEG compression or decompression operation,
19  * but don't destroy the object itself.
20  *
21  * For this, we merely clean up all the nonpermanent memory pools.
22  * Note that temp files (virtual arrays) are not allowed to belong to
23  * the permanent pool, so we will be able to close all temp files here.
24  * Closing a data source or destination, if necessary, is the application's
25  * responsibility.
26  */
27 
28 GLOBAL(void)
30 {
31  int pool;
32 
33  /* Do nothing if called on a not-initialized or destroyed JPEG object. */
34  if (cinfo->mem == NULL)
35  return;
36 
37  /* Releasing pools in reverse order might help avoid fragmentation
38  * with some (brain-damaged) malloc libraries.
39  */
40  for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
41  (*cinfo->mem->free_pool) (cinfo, pool);
42  }
43 
44  /* Reset overall state for possible reuse of object */
45  if (cinfo->is_decompressor) {
46  cinfo->global_state = DSTATE_START;
47  /* Try to keep application from accessing now-deleted marker list.
48  * A bit kludgy to do it here, but this is the most central place.
49  */
50  ((j_decompress_ptr) cinfo)->marker_list = NULL;
51  } else {
52  cinfo->global_state = CSTATE_START;
53  }
54 }
55 
56 
57 /*
58  * Destruction of a JPEG object.
59  *
60  * Everything gets deallocated except the master jpeg_compress_struct itself
61  * and the error manager struct. Both of these are supplied by the application
62  * and must be freed, if necessary, by the application. (Often they are on
63  * the stack and so don't need to be freed anyway.)
64  * Closing a data source or destination, if necessary, is the application's
65  * responsibility.
66  */
67 
68 GLOBAL(void)
70 {
71  /* We need only tell the memory manager to release everything. */
72  /* NB: mem pointer is NULL if memory mgr failed to initialize. */
73  if (cinfo->mem != NULL)
74  (*cinfo->mem->self_destruct) (cinfo);
75  cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */
76  cinfo->global_state = 0; /* mark it destroyed */
77 }
78 
79 
80 /*
81  * Convenience routines for allocating quantization and Huffman tables.
82  * (Would jutils.c be a more reasonable place to put these?)
83  */
84 
87 {
88  JQUANT_TBL *tbl;
89 
90  tbl = (JQUANT_TBL *)
91  (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
92  tbl->sent_table = FALSE; /* make sure this is false in any new table */
93  return tbl;
94 }
95 
96 
99 {
100  JHUFF_TBL *tbl;
101 
102  tbl = (JHUFF_TBL *)
103  (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
104  tbl->sent_table = FALSE; /* make sure this is false in any new table */
105  return tbl;
106 }
struct jpeg_decompress_struct * j_decompress_ptr
Definition: jpeglib.h:286
#define CSTATE_START
Definition: jpegint.h:26
boolean sent_table
Definition: jpeglib.h:119
jpeg_alloc_huff_table(j_common_ptr cinfo)
Definition: jcomapi.c:98
#define SIZEOF(_ar)
Definition: calc.h:97
smooth NULL
Definition: ftsmooth.c:416
jpeg_abort(j_common_ptr cinfo)
Definition: jcomapi.c:29
#define DSTATE_START
Definition: jpegint.h:30
jpeg_alloc_quant_table(j_common_ptr cinfo)
Definition: jcomapi.c:86
#define JPOOL_NUMPOOLS
Definition: jpeglib.h:809
#define GLOBAL(type)
Definition: jmorecfg.h:291
boolean sent_table
Definition: jpeglib.h:103
#define JPOOL_PERMANENT
Definition: jpeglib.h:807
jpeg_destroy(j_common_ptr cinfo)
Definition: jcomapi.c:69