1/* 2 * jcomapi.c 3 * 4 * 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. 8 * For conditions of distribution and use, see the accompanying README file. 9 * 10 * This file contains application interface routines that are used for both 11 * compression and decompression. 12 */ 13 14#define JPEG_INTERNALS 15#include "jinclude.h" 16#include "jpeglib.h" 17 18 19/* 20 * Abort processing of a JPEG compression or decompression operation, 21 * but don't destroy the object itself. 22 * 23 * For this, we merely clean up all the nonpermanent memory pools. 24 * Note that temp files (virtual arrays) are not allowed to belong to 25 * the permanent pool, so we will be able to close all temp files here. 26 * Closing a data source or destination, if necessary, is the application's 27 * responsibility. 28 */ 29 30GLOBAL(void) 31jpeg_abort (j_common_ptr cinfo) 32{ 33 int pool; 34 35 /* Do nothing if called on a not-initialized or destroyed JPEG object. */ 36 if (cinfo->mem == NULL) 37 return; 38 39 /* Releasing pools in reverse order might help avoid fragmentation 40 * with some (brain-damaged) malloc libraries. 41 */ 42 for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) { 43 (*cinfo->mem->free_pool) (cinfo, pool); 44 } 45 46 /* Reset overall state for possible reuse of object */ 47 if (cinfo->is_decompressor) { 48 cinfo->global_state = DSTATE_START; 49 /* Try to keep application from accessing now-deleted marker list. 50 * A bit kludgy to do it here, but this is the most central place. 51 */ 52 ((j_decompress_ptr) cinfo)->marker_list = NULL; 53 } else { 54 cinfo->global_state = CSTATE_START; 55 } 56} 57 58 59/* 60 * Destruction of a JPEG object. 61 * 62 * Everything gets deallocated except the master jpeg_compress_struct itself 63 * and the error manager struct. Both of these are supplied by the application 64 * and must be freed, if necessary, by the application. (Often they are on 65 * the stack and so don't need to be freed anyway.) 66 * Closing a data source or destination, if necessary, is the application's 67 * responsibility. 68 */ 69 70GLOBAL(void) 71jpeg_destroy (j_common_ptr cinfo) 72{ 73 /* We need only tell the memory manager to release everything. */ 74 /* NB: mem pointer is NULL if memory mgr failed to initialize. */ 75 if (cinfo->mem != NULL) 76 (*cinfo->mem->self_destruct) (cinfo); 77 cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */ 78 cinfo->global_state = 0; /* mark it destroyed */ 79} 80 81 82/* 83 * Convenience routines for allocating quantization and Huffman tables. 84 * (Would jutils.c be a more reasonable place to put these?) 85 */ 86 87GLOBAL(JQUANT_TBL *) 88jpeg_alloc_quant_table (j_common_ptr cinfo) 89{ 90 JQUANT_TBL *tbl; 91 92 tbl = (JQUANT_TBL *) 93 (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, sizeof(JQUANT_TBL)); 94 tbl->sent_table = FALSE; /* make sure this is false in any new table */ 95 return tbl; 96} 97 98 99GLOBAL(JHUFF_TBL *) 100jpeg_alloc_huff_table (j_common_ptr cinfo) 101{ 102 JHUFF_TBL *tbl; 103 104 tbl = (JHUFF_TBL *) 105 (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, sizeof(JHUFF_TBL)); 106 tbl->sent_table = FALSE; /* make sure this is false in any new table */ 107 return tbl; 108} 109