ref: 023f5eca58471db968aee3de7729c1c9b0540952
dir: /sys/src/cmd/gs/jpeg/jcomapi.c/
/* * jcomapi.c * * Copyright (C) 1994-1997, Thomas G. Lane. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * * This file contains application interface routines that are used for both * compression and decompression. */ #define JPEG_INTERNALS #include "jinclude.h" #include "jpeglib.h" /* * Abort processing of a JPEG compression or decompression operation, * but don't destroy the object itself. * * For this, we merely clean up all the nonpermanent memory pools. * Note that temp files (virtual arrays) are not allowed to belong to * the permanent pool, so we will be able to close all temp files here. * Closing a data source or destination, if necessary, is the application's * responsibility. */ GLOBAL(void) jpeg_abort (j_common_ptr cinfo) { int pool; /* Do nothing if called on a not-initialized or destroyed JPEG object. */ if (cinfo->mem == NULL) return; /* Releasing pools in reverse order might help avoid fragmentation * with some (brain-damaged) malloc libraries. */ for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) { (*cinfo->mem->free_pool) (cinfo, pool); } /* Reset overall state for possible reuse of object */ if (cinfo->is_decompressor) { cinfo->global_state = DSTATE_START; /* Try to keep application from accessing now-deleted marker list. * A bit kludgy to do it here, but this is the most central place. */ ((j_decompress_ptr) cinfo)->marker_list = NULL; } else { cinfo->global_state = CSTATE_START; } } /* * Destruction of a JPEG object. * * Everything gets deallocated except the master jpeg_compress_struct itself * and the error manager struct. Both of these are supplied by the application * and must be freed, if necessary, by the application. (Often they are on * the stack and so don't need to be freed anyway.) * Closing a data source or destination, if necessary, is the application's * responsibility. */ GLOBAL(void) jpeg_destroy (j_common_ptr cinfo) { /* We need only tell the memory manager to release everything. */ /* NB: mem pointer is NULL if memory mgr failed to initialize. */ if (cinfo->mem != NULL) (*cinfo->mem->self_destruct) (cinfo); cinfo->mem = NULL; /* be safe if jpeg_destroy is called twice */ cinfo->global_state = 0; /* mark it destroyed */ } /* * Convenience routines for allocating quantization and Huffman tables. * (Would jutils.c be a more reasonable place to put these?) */ GLOBAL(JQUANT_TBL *) jpeg_alloc_quant_table (j_common_ptr cinfo) { JQUANT_TBL *tbl; tbl = (JQUANT_TBL *) (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL)); tbl->sent_table = FALSE; /* make sure this is false in any new table */ return tbl; } GLOBAL(JHUFF_TBL *) jpeg_alloc_huff_table (j_common_ptr cinfo) { JHUFF_TBL *tbl; tbl = (JHUFF_TBL *) (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL)); tbl->sent_table = FALSE; /* make sure this is false in any new table */ return tbl; }