4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1992-1996, Thomas G. Lane.
6 * libjpeg-turbo Modifications:
7 * Copyright (C) 2017-2018, D. R. Commander.
8 * For conditions of distribution and use, see the accompanying README.ijg
11 * This file provides a really simple implementation of the system-
12 * dependent portion of the JPEG memory manager. This implementation
13 * assumes that no backing-store files are needed: all required space
14 * can be obtained from malloc().
15 * This is very portable in the sense that it'll compile on almost anything,
16 * but you'd better have lots of main memory (or virtual memory) if you want
17 * to process big images.
20 #define JPEG_INTERNALS
23 #include "jmemsys.h" /* import the system-dependent declarations */
25 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc(),free() */
26 extern void *malloc(size_t size
);
27 extern void free(void *ptr
);
32 * Memory allocation and freeing are controlled by the regular library
33 * routines malloc() and free().
37 jpeg_get_small(j_common_ptr cinfo
, size_t sizeofobject
)
39 return (void *)malloc(sizeofobject
);
43 jpeg_free_small(j_common_ptr cinfo
, void *object
, size_t sizeofobject
)
50 * "Large" objects are treated the same as "small" ones.
54 jpeg_get_large(j_common_ptr cinfo
, size_t sizeofobject
)
56 return (void *)malloc(sizeofobject
);
60 jpeg_free_large(j_common_ptr cinfo
, void *object
, size_t sizeofobject
)
67 * This routine computes the total memory space available for allocation.
71 jpeg_mem_available(j_common_ptr cinfo
, size_t min_bytes_needed
,
72 size_t max_bytes_needed
, size_t already_allocated
)
74 if (cinfo
->mem
->max_memory_to_use
) {
75 if ((size_t)cinfo
->mem
->max_memory_to_use
> already_allocated
)
76 return cinfo
->mem
->max_memory_to_use
- already_allocated
;
80 /* Here we always say, "we got all you want bud!" */
81 return max_bytes_needed
;
87 * Backing store (temporary file) management.
88 * Since jpeg_mem_available always promised the moon,
89 * this should never be called and we can just error out.
93 jpeg_open_backing_store(j_common_ptr cinfo
, backing_store_ptr info
,
94 long total_bytes_needed
)
96 ERREXIT(cinfo
, JERR_NO_BACKING_STORE
);
101 * These routines take care of any system-dependent initialization and
102 * cleanup required. Here, there isn't any.
106 jpeg_mem_init(j_common_ptr cinfo
)
108 return 0; /* just set max_memory_to_use to 0 */
112 jpeg_mem_term(j_common_ptr cinfo
)