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      1 #if !defined(_FX_JPEG_TURBO_)
      2 /*
      3  * jcomapi.c
      4  *
      5  * Copyright (C) 1994-1997, Thomas G. Lane.
      6  * This file is part of the Independent JPEG Group's software.
      7  * For conditions of distribution and use, see the accompanying README file.
      8  *
      9  * This file contains application interface routines that are used for both
     10  * compression and decompression.
     11  */
     12 
     13 #define JPEG_INTERNALS
     14 #include "jinclude.h"
     15 #include "jpeglib.h"
     16 
     17 
     18 /*
     19  * Abort processing of a JPEG compression or decompression operation,
     20  * but don't destroy the object itself.
     21  *
     22  * For this, we merely clean up all the nonpermanent memory pools.
     23  * Note that temp files (virtual arrays) are not allowed to belong to
     24  * the permanent pool, so we will be able to close all temp files here.
     25  * Closing a data source or destination, if necessary, is the application's
     26  * responsibility.
     27  */
     28 
     29 GLOBAL(void)
     30 jpeg_abort (j_common_ptr cinfo)
     31 {
     32   int pool;
     33 
     34   /* Do nothing if called on a not-initialized or destroyed JPEG object. */
     35   if (cinfo->mem == NULL)
     36     return;
     37 
     38   /* Releasing pools in reverse order might help avoid fragmentation
     39    * with some (brain-damaged) malloc libraries.
     40    */
     41   for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
     42     (*cinfo->mem->free_pool) (cinfo, pool);
     43   }
     44 
     45   /* Reset overall state for possible reuse of object */
     46   if (cinfo->is_decompressor) {
     47     cinfo->global_state = DSTATE_START;
     48     /* Try to keep application from accessing now-deleted marker list.
     49      * A bit kludgy to do it here, but this is the most central place.
     50      */
     51     ((j_decompress_ptr) cinfo)->marker_list = NULL;
     52   } else {
     53     cinfo->global_state = CSTATE_START;
     54   }
     55 }
     56 
     57 
     58 /*
     59  * Destruction of a JPEG object.
     60  *
     61  * Everything gets deallocated except the master jpeg_compress_struct itself
     62  * and the error manager struct.  Both of these are supplied by the application
     63  * and must be freed, if necessary, by the application.  (Often they are on
     64  * the stack and so don't need to be freed anyway.)
     65  * Closing a data source or destination, if necessary, is the application's
     66  * responsibility.
     67  */
     68 
     69 GLOBAL(void)
     70 jpeg_destroy (j_common_ptr cinfo)
     71 {
     72   /* We need only tell the memory manager to release everything. */
     73   /* NB: mem pointer is NULL if memory mgr failed to initialize. */
     74   if (cinfo->mem != NULL)
     75     (*cinfo->mem->self_destruct) (cinfo);
     76   cinfo->mem = NULL;		/* be safe if jpeg_destroy is called twice */
     77   cinfo->global_state = 0;	/* mark it destroyed */
     78 }
     79 
     80 
     81 /*
     82  * Convenience routines for allocating quantization and Huffman tables.
     83  * (Would jutils.c be a more reasonable place to put these?)
     84  */
     85 
     86 GLOBAL(JQUANT_TBL *)
     87 jpeg_alloc_quant_table (j_common_ptr cinfo)
     88 {
     89   JQUANT_TBL *tbl;
     90 
     91   tbl = (JQUANT_TBL *)
     92     (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
     93   tbl->sent_table = FALSE;	/* make sure this is false in any new table */
     94   return tbl;
     95 }
     96 
     97 
     98 GLOBAL(JHUFF_TBL *)
     99 jpeg_alloc_huff_table (j_common_ptr cinfo)
    100 {
    101   JHUFF_TBL *tbl;
    102 
    103   tbl = (JHUFF_TBL *)
    104     (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
    105   tbl->sent_table = FALSE;	/* make sure this is false in any new table */
    106   return tbl;
    107 }
    108 
    109 #endif //_FX_JPEG_TURBO_
    110