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Diffstat (limited to 'jpg/jmemsys.h')
| -rw-r--r-- | jpg/jmemsys.h | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/jpg/jmemsys.h b/jpg/jmemsys.h deleted file mode 100644 index 6c3c6d3..0000000 --- a/jpg/jmemsys.h +++ /dev/null @@ -1,198 +0,0 @@ -/* - * jmemsys.h - * - * Copyright (C) 1992-1997, 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 include file defines the interface between the system-independent - * and system-dependent portions of the JPEG memory manager. No other - * modules need include it. (The system-independent portion is jmemmgr.c; - * there are several different versions of the system-dependent portion.) - * - * This file works as-is for the system-dependent memory managers supplied - * in the IJG distribution. You may need to modify it if you write a - * custom memory manager. If system-dependent changes are needed in - * this file, the best method is to #ifdef them based on a configuration - * symbol supplied in jconfig.h, as we have done with USE_MSDOS_MEMMGR - * and USE_MAC_MEMMGR. - */ - - -/* Short forms of external names for systems with brain-damaged linkers. */ - -#ifdef NEED_SHORT_EXTERNAL_NAMES -#define jpeg_get_small jGetSmall -#define jpeg_free_small jFreeSmall -#define jpeg_get_large jGetLarge -#define jpeg_free_large jFreeLarge -#define jpeg_mem_available jMemAvail -#define jpeg_open_backing_store jOpenBackStore -#define jpeg_mem_init jMemInit -#define jpeg_mem_term jMemTerm -#endif /* NEED_SHORT_EXTERNAL_NAMES */ - - -/* - * These two functions are used to allocate and release small chunks of - * memory. (Typically the total amount requested through jpeg_get_small is - * no more than 20K or so; this will be requested in chunks of a few K each.) - * Behavior should be the same as for the standard library functions malloc - * and free; in particular, jpeg_get_small must return NULL on failure. - * On most systems, these ARE malloc and free. jpeg_free_small is passed the - * size of the object being freed, just in case it's needed. - * On an 80x86 machine using small-data memory model, these manage near heap. - */ - -EXTERN(void *) jpeg_get_small JPP((j_common_ptr cinfo, size_t sizeofobject)); -EXTERN(void) jpeg_free_small JPP((j_common_ptr cinfo, void * object, - size_t sizeofobject)); - -/* - * These two functions are used to allocate and release large chunks of - * memory (up to the total free space designated by jpeg_mem_available). - * The interface is the same as above, except that on an 80x86 machine, - * far pointers are used. On most other machines these are identical to - * the jpeg_get/free_small routines; but we keep them separate anyway, - * in case a different allocation strategy is desirable for large chunks. - */ - -EXTERN(void FAR *) jpeg_get_large JPP((j_common_ptr cinfo, - size_t sizeofobject)); -EXTERN(void) jpeg_free_large JPP((j_common_ptr cinfo, void FAR * object, - size_t sizeofobject)); - -/* - * The macro MAX_ALLOC_CHUNK designates the maximum number of bytes that may - * be requested in a single call to jpeg_get_large (and jpeg_get_small for that - * matter, but that case should never come into play). This macro is needed - * to model the 64Kb-segment-size limit of far addressing on 80x86 machines. - * On those machines, we expect that jconfig.h will provide a proper value. - * On machines with 32-bit flat address spaces, any large constant may be used. - * - * NB: jmemmgr.c expects that MAX_ALLOC_CHUNK will be representable as type - * size_t and will be a multiple of sizeof(align_type). - */ - -#ifndef MAX_ALLOC_CHUNK /* may be overridden in jconfig.h */ -#define MAX_ALLOC_CHUNK 1000000000L -#endif - -/* - * This routine computes the total space still available for allocation by - * jpeg_get_large. If more space than this is needed, backing store will be - * used. NOTE: any memory already allocated must not be counted. - * - * There is a minimum space requirement, corresponding to the minimum - * feasible buffer sizes; jmemmgr.c will request that much space even if - * jpeg_mem_available returns zero. The maximum space needed, enough to hold - * all working storage in memory, is also passed in case it is useful. - * Finally, the total space already allocated is passed. If no better - * method is available, cinfo->mem->max_memory_to_use - already_allocated - * is often a suitable calculation. - * - * It is OK for jpeg_mem_available to underestimate the space available - * (that'll just lead to more backing-store access than is really necessary). - * However, an overestimate will lead to failure. Hence it's wise to subtract - * a slop factor from the true available space. 5% should be enough. - * - * On machines with lots of virtual memory, any large constant may be returned. - * Conversely, zero may be returned to always use the minimum amount of memory. - */ - -EXTERN(long) jpeg_mem_available JPP((j_common_ptr cinfo, - long min_bytes_needed, - long max_bytes_needed, - long already_allocated)); - - -/* - * This structure holds whatever state is needed to access a single - * backing-store object. The read/write/close method pointers are called - * by jmemmgr.c to manipulate the backing-store object; all other fields - * are private to the system-dependent backing store routines. - */ - -#define TEMP_NAME_LENGTH 64 /* max length of a temporary file's name */ - - -#ifdef USE_MSDOS_MEMMGR /* DOS-specific junk */ - -typedef unsigned short XMSH; /* type of extended-memory handles */ -typedef unsigned short EMSH; /* type of expanded-memory handles */ - -typedef union { - short file_handle; /* DOS file handle if it's a temp file */ - XMSH xms_handle; /* handle if it's a chunk of XMS */ - EMSH ems_handle; /* handle if it's a chunk of EMS */ -} handle_union; - -#endif /* USE_MSDOS_MEMMGR */ - -#ifdef USE_MAC_MEMMGR /* Mac-specific junk */ -#include <Files.h> -#endif /* USE_MAC_MEMMGR */ - - -typedef struct backing_store_struct * backing_store_ptr; - -typedef struct backing_store_struct { - /* Methods for reading/writing/closing this backing-store object */ - JMETHOD(void, read_backing_store, (j_common_ptr cinfo, - backing_store_ptr info, - void FAR * buffer_address, - long file_offset, long byte_count)); - JMETHOD(void, write_backing_store, (j_common_ptr cinfo, - backing_store_ptr info, - void FAR * buffer_address, - long file_offset, long byte_count)); - JMETHOD(void, close_backing_store, (j_common_ptr cinfo, - backing_store_ptr info)); - - /* Private fields for system-dependent backing-store management */ -#ifdef USE_MSDOS_MEMMGR - /* For the MS-DOS manager (jmemdos.c), we need: */ - handle_union handle; /* reference to backing-store storage object */ - char temp_name[TEMP_NAME_LENGTH]; /* name if it's a file */ -#else -#ifdef USE_MAC_MEMMGR - /* For the Mac manager (jmemmac.c), we need: */ - short temp_file; /* file reference number to temp file */ - FSSpec tempSpec; /* the FSSpec for the temp file */ - char temp_name[TEMP_NAME_LENGTH]; /* name if it's a file */ -#else - /* For a typical implementation with temp files, we need: */ - FILE * temp_file; /* stdio reference to temp file */ - char temp_name[TEMP_NAME_LENGTH]; /* name of temp file */ -#endif -#endif -} backing_store_info; - - -/* - * Initial opening of a backing-store object. This must fill in the - * read/write/close pointers in the object. The read/write routines - * may take an error exit if the specified maximum file size is exceeded. - * (If jpeg_mem_available always returns a large value, this routine can - * just take an error exit.) - */ - -EXTERN(void) jpeg_open_backing_store JPP((j_common_ptr cinfo, - backing_store_ptr info, - long total_bytes_needed)); - - -/* - * These routines take care of any system-dependent initialization and - * cleanup required. jpeg_mem_init will be called before anything is - * allocated (and, therefore, nothing in cinfo is of use except the error - * manager pointer). It should return a suitable default value for - * max_memory_to_use; this may subsequently be overridden by the surrounding - * application. (Note that max_memory_to_use is only important if - * jpeg_mem_available chooses to consult it ... no one else will.) - * jpeg_mem_term may assume that all requested memory has been freed and that - * all opened backing-store objects have been closed. - */ - -EXTERN(long) jpeg_mem_init JPP((j_common_ptr cinfo)); -EXTERN(void) jpeg_mem_term JPP((j_common_ptr cinfo)); |