4
* Copyright (C) 1991-1995, Thomas G. Lane.
5
* This file is part of the Independent JPEG Group's software.
6
* For conditions of distribution and use, see the accompanying README file.
8
* This file contains the JPEG system-independent memory management
9
* routines. This code is usable across a wide variety of machines; most
10
* of the system dependencies have been isolated in a separate file.
11
* The major functions provided here are:
12
* * pool-based allocation and freeing of memory;
13
* * policy decisions about how to divide available memory among the
15
* * control logic for swapping virtual arrays between main memory and
17
* The separate system-dependent file provides the actual backing-storage
18
* access code, and it contains the policy decision about how much total
20
* This file is system-dependent in the sense that some of its functions
21
* are unnecessary in some systems. For example, if there is enough virtual
22
* memory so that backing storage will never be used, much of the virtual
23
* array control logic could be removed. (Of course, if you have that much
24
* memory then you shouldn't care about a little bit of unused code...)
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#define JPEG_INTERNALS
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#define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */
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#include "jmemsys.h" /* import the system-dependent declarations */
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#ifndef HAVE_STDLIB_H /* <stdlib.h> should declare getenv() */
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extern char * getenv JPP((const char * name));
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* Some important notes:
42
* The allocation routines provided here must never return NULL.
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* They should exit to error_exit if unsuccessful.
45
* It's not a good idea to try to merge the sarray and barray routines,
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* even though they are textually almost the same, because samples are
47
* usually stored as bytes while coefficients are shorts or ints. Thus,
48
* in machines where byte pointers have a different representation from
49
* word pointers, the resulting machine code could not be the same.
54
* Many machines require storage alignment: longs must start on 4-byte
55
* boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc()
56
* always returns pointers that are multiples of the worst-case alignment
57
* requirement, and we had better do so too.
58
* There isn't any really portable way to determine the worst-case alignment
59
* requirement. This module assumes that the alignment requirement is
60
* multiples of sizeof(ALIGN_TYPE).
61
* By default, we define ALIGN_TYPE as double. This is necessary on some
62
* workstations (where doubles really do need 8-byte alignment) and will work
63
* fine on nearly everything. If your machine has lesser alignment needs,
64
* you can save a few bytes by making ALIGN_TYPE smaller.
65
* The only place I know of where this will NOT work is certain Macintosh
66
* 680x0 compilers that define double as a 10-byte IEEE extended float.
67
* Doing 10-byte alignment is counterproductive because longwords won't be
68
* aligned well. Put "#define ALIGN_TYPE long" in jconfig.h if you have
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#ifndef ALIGN_TYPE /* so can override from jconfig.h */
73
#define ALIGN_TYPE double
78
* We allocate objects from "pools", where each pool is gotten with a single
79
* request to jpeg_get_small() or jpeg_get_large(). There is no per-object
80
* overhead within a pool, except for alignment padding. Each pool has a
81
* header with a link to the next pool of the same class.
82
* Small and large pool headers are identical except that the latter's
83
* link pointer must be FAR on 80x86 machines.
84
* Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE
85
* field. This forces the compiler to make SIZEOF(small_pool_hdr) a multiple
86
* of the alignment requirement of ALIGN_TYPE.
89
typedef union small_pool_struct * small_pool_ptr;
91
typedef union small_pool_struct {
93
small_pool_ptr next; /* next in list of pools */
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size_t bytes_used; /* how many bytes already used within pool */
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size_t bytes_left; /* bytes still available in this pool */
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ALIGN_TYPE dummy; /* included in union to ensure alignment */
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typedef union large_pool_struct FAR * large_pool_ptr;
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typedef union large_pool_struct {
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large_pool_ptr next; /* next in list of pools */
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size_t bytes_used; /* how many bytes already used within pool */
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size_t bytes_left; /* bytes still available in this pool */
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ALIGN_TYPE dummy; /* included in union to ensure alignment */
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* Here is the full definition of a memory manager object.
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struct jpeg_memory_mgr pub; /* public fields */
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/* Each pool identifier (lifetime class) names a linked list of pools. */
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small_pool_ptr small_list[JPOOL_NUMPOOLS];
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large_pool_ptr large_list[JPOOL_NUMPOOLS];
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/* Since we only have one lifetime class of virtual arrays, only one
124
* linked list is necessary (for each datatype). Note that the virtual
125
* array control blocks being linked together are actually stored somewhere
126
* in the small-pool list.
128
jvirt_sarray_ptr virt_sarray_list;
129
jvirt_barray_ptr virt_barray_list;
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/* This counts total space obtained from jpeg_get_small/large */
132
long total_space_allocated;
134
/* alloc_sarray and alloc_barray set this value for use by virtual
137
JDIMENSION last_rowsperchunk; /* from most recent alloc_sarray/barray */
140
typedef my_memory_mgr * my_mem_ptr;
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* The control blocks for virtual arrays.
145
* Note that these blocks are allocated in the "small" pool area.
146
* System-dependent info for the associated backing store (if any) is hidden
147
* inside the backing_store_info struct.
150
struct jvirt_sarray_control {
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JSAMPARRAY mem_buffer; /* => the in-memory buffer */
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JDIMENSION rows_in_array; /* total virtual array height */
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JDIMENSION samplesperrow; /* width of array (and of memory buffer) */
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JDIMENSION maxaccess; /* max rows accessed by access_virt_sarray */
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JDIMENSION rows_in_mem; /* height of memory buffer */
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JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
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JDIMENSION cur_start_row; /* first logical row # in the buffer */
158
JDIMENSION first_undef_row; /* row # of first uninitialized row */
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boolean pre_zero; /* pre-zero mode requested? */
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boolean dirty; /* do current buffer contents need written? */
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boolean b_s_open; /* is backing-store data valid? */
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jvirt_sarray_ptr next; /* link to next virtual sarray control block */
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backing_store_info b_s_info; /* System-dependent control info */
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struct jvirt_barray_control {
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JBLOCKARRAY mem_buffer; /* => the in-memory buffer */
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JDIMENSION rows_in_array; /* total virtual array height */
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JDIMENSION blocksperrow; /* width of array (and of memory buffer) */
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JDIMENSION maxaccess; /* max rows accessed by access_virt_barray */
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JDIMENSION rows_in_mem; /* height of memory buffer */
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JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
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JDIMENSION cur_start_row; /* first logical row # in the buffer */
174
JDIMENSION first_undef_row; /* row # of first uninitialized row */
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boolean pre_zero; /* pre-zero mode requested? */
176
boolean dirty; /* do current buffer contents need written? */
177
boolean b_s_open; /* is backing-store data valid? */
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jvirt_barray_ptr next; /* link to next virtual barray control block */
179
backing_store_info b_s_info; /* System-dependent control info */
183
#ifdef MEM_STATS /* optional extra stuff for statistics */
186
print_mem_stats (j_common_ptr cinfo, int pool_id)
188
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
189
small_pool_ptr shdr_ptr;
190
large_pool_ptr lhdr_ptr;
192
/* Since this is only a debugging stub, we can cheat a little by using
193
* fprintf directly rather than going through the trace message code.
194
* This is helpful because message parm array can't handle longs.
196
fprintf(stderr, "Freeing pool %d, total space = %ld\n",
197
pool_id, mem->total_space_allocated);
199
for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL;
200
lhdr_ptr = lhdr_ptr->hdr.next) {
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fprintf(stderr, " Large chunk used %ld\n",
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(long) lhdr_ptr->hdr.bytes_used);
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for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL;
206
shdr_ptr = shdr_ptr->hdr.next) {
207
fprintf(stderr, " Small chunk used %ld free %ld\n",
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(long) shdr_ptr->hdr.bytes_used,
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(long) shdr_ptr->hdr.bytes_left);
213
#endif /* MEM_STATS */
217
out_of_memory (j_common_ptr cinfo, int which)
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/* Report an out-of-memory error and stop execution */
219
/* If we compiled MEM_STATS support, report alloc requests before dying */
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cinfo->err->trace_level = 2; /* force self_destruct to report stats */
224
ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which);
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* Allocation of "small" objects.
231
* For these, we use pooled storage. When a new pool must be created,
232
* we try to get enough space for the current request plus a "slop" factor,
233
* where the slop will be the amount of leftover space in the new pool.
234
* The speed vs. space tradeoff is largely determined by the slop values.
235
* A different slop value is provided for each pool class (lifetime),
236
* and we also distinguish the first pool of a class from later ones.
237
* NOTE: the values given work fairly well on both 16- and 32-bit-int
238
* machines, but may be too small if longs are 64 bits or more.
241
static const size_t first_pool_slop[JPOOL_NUMPOOLS] =
243
1600, /* first PERMANENT pool */
244
16000 /* first IMAGE pool */
247
static const size_t extra_pool_slop[JPOOL_NUMPOOLS] =
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0, /* additional PERMANENT pools */
250
5000 /* additional IMAGE pools */
253
#define MIN_SLOP 50 /* greater than 0 to avoid futile looping */
257
alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
258
/* Allocate a "small" object */
260
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
261
small_pool_ptr hdr_ptr, prev_hdr_ptr;
263
size_t odd_bytes, min_request, slop;
265
/* Check for unsatisfiable request (do now to ensure no overflow below) */
266
if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(small_pool_hdr)))
267
out_of_memory(cinfo, 1); /* request exceeds malloc's ability */
269
/* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
270
odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
272
sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
274
/* See if space is available in any existing pool */
275
if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
276
ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
278
hdr_ptr = mem->small_list[pool_id];
279
while (hdr_ptr != NULL) {
280
if (hdr_ptr->hdr.bytes_left >= sizeofobject)
281
break; /* found pool with enough space */
282
prev_hdr_ptr = hdr_ptr;
283
hdr_ptr = hdr_ptr->hdr.next;
286
/* Time to make a new pool? */
287
if (hdr_ptr == NULL) {
288
/* min_request is what we need now, slop is what will be leftover */
289
min_request = sizeofobject + SIZEOF(small_pool_hdr);
290
if (prev_hdr_ptr == NULL) /* first pool in class? */
291
slop = first_pool_slop[pool_id];
293
slop = extra_pool_slop[pool_id];
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/* Don't ask for more than MAX_ALLOC_CHUNK */
295
if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request))
296
slop = (size_t) (MAX_ALLOC_CHUNK-min_request);
297
/* Try to get space, if fail reduce slop and try again */
299
hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop);
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if (slop < MIN_SLOP) /* give up when it gets real small */
304
out_of_memory(cinfo, 2); /* jpeg_get_small failed */
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mem->total_space_allocated += min_request + slop;
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/* Success, initialize the new pool header and add to end of list */
308
hdr_ptr->hdr.next = NULL;
309
hdr_ptr->hdr.bytes_used = 0;
310
hdr_ptr->hdr.bytes_left = sizeofobject + slop;
311
if (prev_hdr_ptr == NULL) /* first pool in class? */
312
mem->small_list[pool_id] = hdr_ptr;
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prev_hdr_ptr->hdr.next = hdr_ptr;
317
/* OK, allocate the object from the current pool */
318
data_ptr = (char *) (hdr_ptr + 1); /* point to first data byte in pool */
319
data_ptr += hdr_ptr->hdr.bytes_used; /* point to place for object */
320
hdr_ptr->hdr.bytes_used += sizeofobject;
321
hdr_ptr->hdr.bytes_left -= sizeofobject;
323
return (void *) data_ptr;
328
* Allocation of "large" objects.
330
* The external semantics of these are the same as "small" objects,
331
* except that FAR pointers are used on 80x86. However the pool
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* management heuristics are quite different. We assume that each
333
* request is large enough that it may as well be passed directly to
334
* jpeg_get_large; the pool management just links everything together
335
* so that we can free it all on demand.
336
* Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY
337
* structures. The routines that create these structures (see below)
338
* deliberately bunch rows together to ensure a large request size.
342
alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
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/* Allocate a "large" object */
345
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
346
large_pool_ptr hdr_ptr;
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/* Check for unsatisfiable request (do now to ensure no overflow below) */
350
if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)))
351
out_of_memory(cinfo, 3); /* request exceeds malloc's ability */
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/* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
354
odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
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sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
358
/* Always make a new pool */
359
if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
360
ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
362
hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject +
363
SIZEOF(large_pool_hdr));
365
out_of_memory(cinfo, 4); /* jpeg_get_large failed */
366
mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr);
368
/* Success, initialize the new pool header and add to list */
369
hdr_ptr->hdr.next = mem->large_list[pool_id];
370
/* We maintain space counts in each pool header for statistical purposes,
371
* even though they are not needed for allocation.
373
hdr_ptr->hdr.bytes_used = sizeofobject;
374
hdr_ptr->hdr.bytes_left = 0;
375
mem->large_list[pool_id] = hdr_ptr;
377
return (void FAR *) (hdr_ptr + 1); /* point to first data byte in pool */
382
* Creation of 2-D sample arrays.
383
* The pointers are in near heap, the samples themselves in FAR heap.
385
* To minimize allocation overhead and to allow I/O of large contiguous
386
* blocks, we allocate the sample rows in groups of as many rows as possible
387
* without exceeding MAX_ALLOC_CHUNK total bytes per allocation request.
388
* NB: the virtual array control routines, later in this file, know about
389
* this chunking of rows. The rowsperchunk value is left in the mem manager
390
* object so that it can be saved away if this sarray is the workspace for
395
alloc_sarray (j_common_ptr cinfo, int pool_id,
396
JDIMENSION samplesperrow, JDIMENSION numrows)
397
/* Allocate a 2-D sample array */
399
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
402
JDIMENSION rowsperchunk, currow, i;
405
/* Calculate max # of rows allowed in one allocation chunk */
406
ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
407
((long) samplesperrow * SIZEOF(JSAMPLE));
409
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
410
if (ltemp < (long) numrows)
411
rowsperchunk = (JDIMENSION) ltemp;
413
rowsperchunk = numrows;
414
mem->last_rowsperchunk = rowsperchunk;
416
/* Get space for row pointers (small object) */
417
result = (JSAMPARRAY) alloc_small(cinfo, pool_id,
418
(size_t) (numrows * SIZEOF(JSAMPROW)));
420
/* Get the rows themselves (large objects) */
422
while (currow < numrows) {
423
rowsperchunk = MIN(rowsperchunk, numrows - currow);
424
workspace = (JSAMPROW) alloc_large(cinfo, pool_id,
425
(size_t) ((size_t) rowsperchunk * (size_t) samplesperrow
427
for (i = rowsperchunk; i > 0; i--) {
428
result[currow++] = workspace;
429
workspace += samplesperrow;
438
* Creation of 2-D coefficient-block arrays.
439
* This is essentially the same as the code for sample arrays, above.
442
METHODDEF JBLOCKARRAY
443
alloc_barray (j_common_ptr cinfo, int pool_id,
444
JDIMENSION blocksperrow, JDIMENSION numrows)
445
/* Allocate a 2-D coefficient-block array */
447
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
450
JDIMENSION rowsperchunk, currow, i;
453
/* Calculate max # of rows allowed in one allocation chunk */
454
ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
455
((long) blocksperrow * SIZEOF(JBLOCK));
457
ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
458
if (ltemp < (long) numrows)
459
rowsperchunk = (JDIMENSION) ltemp;
461
rowsperchunk = numrows;
462
mem->last_rowsperchunk = rowsperchunk;
464
/* Get space for row pointers (small object) */
465
result = (JBLOCKARRAY) alloc_small(cinfo, pool_id,
466
(size_t) (numrows * SIZEOF(JBLOCKROW)));
468
/* Get the rows themselves (large objects) */
470
while (currow < numrows) {
471
rowsperchunk = MIN(rowsperchunk, numrows - currow);
472
workspace = (JBLOCKROW) alloc_large(cinfo, pool_id,
473
(size_t) ((size_t) rowsperchunk * (size_t) blocksperrow
475
for (i = rowsperchunk; i > 0; i--) {
476
result[currow++] = workspace;
477
workspace += blocksperrow;
486
* About virtual array management:
488
* The above "normal" array routines are only used to allocate strip buffers
489
* (as wide as the image, but just a few rows high). Full-image-sized buffers
490
* are handled as "virtual" arrays. The array is still accessed a strip at a
491
* time, but the memory manager must save the whole array for repeated
492
* accesses. The intended implementation is that there is a strip buffer in
493
* memory (as high as is possible given the desired memory limit), plus a
494
* backing file that holds the rest of the array.
496
* The request_virt_array routines are told the total size of the image and
497
* the maximum number of rows that will be accessed at once. The in-memory
498
* buffer must be at least as large as the maxaccess value.
500
* The request routines create control blocks but not the in-memory buffers.
501
* That is postponed until realize_virt_arrays is called. At that time the
502
* total amount of space needed is known (approximately, anyway), so free
503
* memory can be divided up fairly.
505
* The access_virt_array routines are responsible for making a specific strip
506
* area accessible (after reading or writing the backing file, if necessary).
507
* Note that the access routines are told whether the caller intends to modify
508
* the accessed strip; during a read-only pass this saves having to rewrite
509
* data to disk. The access routines are also responsible for pre-zeroing
510
* any newly accessed rows, if pre-zeroing was requested.
512
* In current usage, the access requests are usually for nonoverlapping
513
* strips; that is, successive access start_row numbers differ by exactly
514
* num_rows = maxaccess. This means we can get good performance with simple
515
* buffer dump/reload logic, by making the in-memory buffer be a multiple
516
* of the access height; then there will never be accesses across bufferload
517
* boundaries. The code will still work with overlapping access requests,
518
* but it doesn't handle bufferload overlaps very efficiently.
522
METHODDEF jvirt_sarray_ptr
523
request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
524
JDIMENSION samplesperrow, JDIMENSION numrows,
525
JDIMENSION maxaccess)
526
/* Request a virtual 2-D sample array */
528
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
529
jvirt_sarray_ptr result;
531
/* Only IMAGE-lifetime virtual arrays are currently supported */
532
if (pool_id != JPOOL_IMAGE)
533
ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
535
/* get control block */
536
result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id,
537
SIZEOF(struct jvirt_sarray_control));
539
result->mem_buffer = NULL; /* marks array not yet realized */
540
result->rows_in_array = numrows;
541
result->samplesperrow = samplesperrow;
542
result->maxaccess = maxaccess;
543
result->pre_zero = pre_zero;
544
result->b_s_open = FALSE; /* no associated backing-store object */
545
result->next = mem->virt_sarray_list; /* add to list of virtual arrays */
546
mem->virt_sarray_list = result;
552
METHODDEF jvirt_barray_ptr
553
request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
554
JDIMENSION blocksperrow, JDIMENSION numrows,
555
JDIMENSION maxaccess)
556
/* Request a virtual 2-D coefficient-block array */
558
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
559
jvirt_barray_ptr result;
561
/* Only IMAGE-lifetime virtual arrays are currently supported */
562
if (pool_id != JPOOL_IMAGE)
563
ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
565
/* get control block */
566
result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id,
567
SIZEOF(struct jvirt_barray_control));
569
result->mem_buffer = NULL; /* marks array not yet realized */
570
result->rows_in_array = numrows;
571
result->blocksperrow = blocksperrow;
572
result->maxaccess = maxaccess;
573
result->pre_zero = pre_zero;
574
result->b_s_open = FALSE; /* no associated backing-store object */
575
result->next = mem->virt_barray_list; /* add to list of virtual arrays */
576
mem->virt_barray_list = result;
583
realize_virt_arrays (j_common_ptr cinfo)
584
/* Allocate the in-memory buffers for any unrealized virtual arrays */
586
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
587
long space_per_minheight, maximum_space, avail_mem;
588
long minheights, max_minheights;
589
jvirt_sarray_ptr sptr;
590
jvirt_barray_ptr bptr;
592
/* Compute the minimum space needed (maxaccess rows in each buffer)
593
* and the maximum space needed (full image height in each buffer).
594
* These may be of use to the system-dependent jpeg_mem_available routine.
596
space_per_minheight = 0;
598
for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
599
if (sptr->mem_buffer == NULL) { /* if not realized yet */
600
space_per_minheight += (long) sptr->maxaccess *
601
(long) sptr->samplesperrow * SIZEOF(JSAMPLE);
602
maximum_space += (long) sptr->rows_in_array *
603
(long) sptr->samplesperrow * SIZEOF(JSAMPLE);
606
for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
607
if (bptr->mem_buffer == NULL) { /* if not realized yet */
608
space_per_minheight += (long) bptr->maxaccess *
609
(long) bptr->blocksperrow * SIZEOF(JBLOCK);
610
maximum_space += (long) bptr->rows_in_array *
611
(long) bptr->blocksperrow * SIZEOF(JBLOCK);
615
if (space_per_minheight <= 0)
616
return; /* no unrealized arrays, no work */
618
/* Determine amount of memory to actually use; this is system-dependent. */
619
avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space,
620
mem->total_space_allocated);
622
/* If the maximum space needed is available, make all the buffers full
623
* height; otherwise parcel it out with the same number of minheights
626
if (avail_mem >= maximum_space)
627
max_minheights = 1000000000L;
629
max_minheights = avail_mem / space_per_minheight;
630
/* If there doesn't seem to be enough space, try to get the minimum
631
* anyway. This allows a "stub" implementation of jpeg_mem_available().
633
if (max_minheights <= 0)
637
/* Allocate the in-memory buffers and initialize backing store as needed. */
639
for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
640
if (sptr->mem_buffer == NULL) { /* if not realized yet */
641
minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L;
642
if (minheights <= max_minheights) {
643
/* This buffer fits in memory */
644
sptr->rows_in_mem = sptr->rows_in_array;
646
/* It doesn't fit in memory, create backing store. */
647
sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess);
648
jpeg_open_backing_store(cinfo, & sptr->b_s_info,
649
(long) sptr->rows_in_array *
650
(long) sptr->samplesperrow *
651
(long) SIZEOF(JSAMPLE));
652
sptr->b_s_open = TRUE;
654
sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE,
655
sptr->samplesperrow, sptr->rows_in_mem);
656
sptr->rowsperchunk = mem->last_rowsperchunk;
657
sptr->cur_start_row = 0;
658
sptr->first_undef_row = 0;
663
for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
664
if (bptr->mem_buffer == NULL) { /* if not realized yet */
665
minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L;
666
if (minheights <= max_minheights) {
667
/* This buffer fits in memory */
668
bptr->rows_in_mem = bptr->rows_in_array;
670
/* It doesn't fit in memory, create backing store. */
671
bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess);
672
jpeg_open_backing_store(cinfo, & bptr->b_s_info,
673
(long) bptr->rows_in_array *
674
(long) bptr->blocksperrow *
675
(long) SIZEOF(JBLOCK));
676
bptr->b_s_open = TRUE;
678
bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE,
679
bptr->blocksperrow, bptr->rows_in_mem);
680
bptr->rowsperchunk = mem->last_rowsperchunk;
681
bptr->cur_start_row = 0;
682
bptr->first_undef_row = 0;
690
do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing)
691
/* Do backing store read or write of a virtual sample array */
693
long bytesperrow, file_offset, byte_count, rows, thisrow, i;
695
bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE);
696
file_offset = ptr->cur_start_row * bytesperrow;
697
/* Loop to read or write each allocation chunk in mem_buffer */
698
for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
699
/* One chunk, but check for short chunk at end of buffer */
700
rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
701
/* Transfer no more than is currently defined */
702
thisrow = (long) ptr->cur_start_row + i;
703
rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
704
/* Transfer no more than fits in file */
705
rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
706
if (rows <= 0) /* this chunk might be past end of file! */
708
byte_count = rows * bytesperrow;
710
(*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
711
(void FAR *) ptr->mem_buffer[i],
712
file_offset, byte_count);
714
(*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
715
(void FAR *) ptr->mem_buffer[i],
716
file_offset, byte_count);
717
file_offset += byte_count;
723
do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing)
724
/* Do backing store read or write of a virtual coefficient-block array */
726
long bytesperrow, file_offset, byte_count, rows, thisrow, i;
728
bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK);
729
file_offset = ptr->cur_start_row * bytesperrow;
730
/* Loop to read or write each allocation chunk in mem_buffer */
731
for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
732
/* One chunk, but check for short chunk at end of buffer */
733
rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
734
/* Transfer no more than is currently defined */
735
thisrow = (long) ptr->cur_start_row + i;
736
rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
737
/* Transfer no more than fits in file */
738
rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
739
if (rows <= 0) /* this chunk might be past end of file! */
741
byte_count = rows * bytesperrow;
743
(*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
744
(void FAR *) ptr->mem_buffer[i],
745
file_offset, byte_count);
747
(*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
748
(void FAR *) ptr->mem_buffer[i],
749
file_offset, byte_count);
750
file_offset += byte_count;
756
access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
757
JDIMENSION start_row, JDIMENSION num_rows,
759
/* Access the part of a virtual sample array starting at start_row */
760
/* and extending for num_rows rows. writable is true if */
761
/* caller intends to modify the accessed area. */
763
JDIMENSION end_row = start_row + num_rows;
764
JDIMENSION undef_row;
766
/* debugging check */
767
if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
768
ptr->mem_buffer == NULL)
769
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
771
/* Make the desired part of the virtual array accessible */
772
if (start_row < ptr->cur_start_row ||
773
end_row > ptr->cur_start_row+ptr->rows_in_mem) {
775
ERREXIT(cinfo, JERR_VIRTUAL_BUG);
776
/* Flush old buffer contents if necessary */
778
do_sarray_io(cinfo, ptr, TRUE);
781
/* Decide what part of virtual array to access.
782
* Algorithm: if target address > current window, assume forward scan,
783
* load starting at target address. If target address < current window,
784
* assume backward scan, load so that target area is top of window.
785
* Note that when switching from forward write to forward read, will have
786
* start_row = 0, so the limiting case applies and we load from 0 anyway.
788
if (start_row > ptr->cur_start_row) {
789
ptr->cur_start_row = start_row;
791
/* use long arithmetic here to avoid overflow & unsigned problems */
794
ltemp = (long) end_row - (long) ptr->rows_in_mem;
796
ltemp = 0; /* don't fall off front end of file */
797
ptr->cur_start_row = (JDIMENSION) ltemp;
799
/* Read in the selected part of the array.
800
* During the initial write pass, we will do no actual read
801
* because the selected part is all undefined.
803
do_sarray_io(cinfo, ptr, FALSE);
805
/* Ensure the accessed part of the array is defined; prezero if needed.
806
* To improve locality of access, we only prezero the part of the array
807
* that the caller is about to access, not the entire in-memory array.
809
if (ptr->first_undef_row < end_row) {
810
if (ptr->first_undef_row < start_row) {
811
if (writable) /* writer skipped over a section of array */
812
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
813
undef_row = start_row; /* but reader is allowed to read ahead */
815
undef_row = ptr->first_undef_row;
818
ptr->first_undef_row = end_row;
820
size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE);
821
undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
822
end_row -= ptr->cur_start_row;
823
while (undef_row < end_row) {
824
jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
828
if (! writable) /* reader looking at undefined data */
829
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
832
/* Flag the buffer dirty if caller will write in it */
835
/* Return address of proper part of the buffer */
836
return ptr->mem_buffer + (start_row - ptr->cur_start_row);
840
METHODDEF JBLOCKARRAY
841
access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr,
842
JDIMENSION start_row, JDIMENSION num_rows,
844
/* Access the part of a virtual block array starting at start_row */
845
/* and extending for num_rows rows. writable is true if */
846
/* caller intends to modify the accessed area. */
848
JDIMENSION end_row = start_row + num_rows;
849
JDIMENSION undef_row;
851
/* debugging check */
852
if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
853
ptr->mem_buffer == NULL)
854
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
856
/* Make the desired part of the virtual array accessible */
857
if (start_row < ptr->cur_start_row ||
858
end_row > ptr->cur_start_row+ptr->rows_in_mem) {
860
ERREXIT(cinfo, JERR_VIRTUAL_BUG);
861
/* Flush old buffer contents if necessary */
863
do_barray_io(cinfo, ptr, TRUE);
866
/* Decide what part of virtual array to access.
867
* Algorithm: if target address > current window, assume forward scan,
868
* load starting at target address. If target address < current window,
869
* assume backward scan, load so that target area is top of window.
870
* Note that when switching from forward write to forward read, will have
871
* start_row = 0, so the limiting case applies and we load from 0 anyway.
873
if (start_row > ptr->cur_start_row) {
874
ptr->cur_start_row = start_row;
876
/* use long arithmetic here to avoid overflow & unsigned problems */
879
ltemp = (long) end_row - (long) ptr->rows_in_mem;
881
ltemp = 0; /* don't fall off front end of file */
882
ptr->cur_start_row = (JDIMENSION) ltemp;
884
/* Read in the selected part of the array.
885
* During the initial write pass, we will do no actual read
886
* because the selected part is all undefined.
888
do_barray_io(cinfo, ptr, FALSE);
890
/* Ensure the accessed part of the array is defined; prezero if needed.
891
* To improve locality of access, we only prezero the part of the array
892
* that the caller is about to access, not the entire in-memory array.
894
if (ptr->first_undef_row < end_row) {
895
if (ptr->first_undef_row < start_row) {
896
if (writable) /* writer skipped over a section of array */
897
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
898
undef_row = start_row; /* but reader is allowed to read ahead */
900
undef_row = ptr->first_undef_row;
903
ptr->first_undef_row = end_row;
905
size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK);
906
undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
907
end_row -= ptr->cur_start_row;
908
while (undef_row < end_row) {
909
jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
913
if (! writable) /* reader looking at undefined data */
914
ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
917
/* Flag the buffer dirty if caller will write in it */
920
/* Return address of proper part of the buffer */
921
return ptr->mem_buffer + (start_row - ptr->cur_start_row);
926
* Release all objects belonging to a specified pool.
930
free_pool (j_common_ptr cinfo, int pool_id)
932
my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
933
small_pool_ptr shdr_ptr;
934
large_pool_ptr lhdr_ptr;
937
if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
938
ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
941
if (cinfo->err->trace_level > 1)
942
print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */
945
/* If freeing IMAGE pool, close any virtual arrays first */
946
if (pool_id == JPOOL_IMAGE) {
947
jvirt_sarray_ptr sptr;
948
jvirt_barray_ptr bptr;
950
for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
951
if (sptr->b_s_open) { /* there may be no backing store */
952
sptr->b_s_open = FALSE; /* prevent recursive close if error */
953
(*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info);
956
mem->virt_sarray_list = NULL;
957
for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
958
if (bptr->b_s_open) { /* there may be no backing store */
959
bptr->b_s_open = FALSE; /* prevent recursive close if error */
960
(*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info);
963
mem->virt_barray_list = NULL;
966
/* Release large objects */
967
lhdr_ptr = mem->large_list[pool_id];
968
mem->large_list[pool_id] = NULL;
970
while (lhdr_ptr != NULL) {
971
large_pool_ptr next_lhdr_ptr = lhdr_ptr->hdr.next;
972
space_freed = lhdr_ptr->hdr.bytes_used +
973
lhdr_ptr->hdr.bytes_left +
974
SIZEOF(large_pool_hdr);
975
jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed);
976
mem->total_space_allocated -= space_freed;
977
lhdr_ptr = next_lhdr_ptr;
980
/* Release small objects */
981
shdr_ptr = mem->small_list[pool_id];
982
mem->small_list[pool_id] = NULL;
984
while (shdr_ptr != NULL) {
985
small_pool_ptr next_shdr_ptr = shdr_ptr->hdr.next;
986
space_freed = shdr_ptr->hdr.bytes_used +
987
shdr_ptr->hdr.bytes_left +
988
SIZEOF(small_pool_hdr);
989
jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed);
990
mem->total_space_allocated -= space_freed;
991
shdr_ptr = next_shdr_ptr;
997
* Close up shop entirely.
998
* Note that this cannot be called unless cinfo->mem is non-NULL.
1002
self_destruct (j_common_ptr cinfo)
1006
/* Close all backing store, release all memory.
1007
* Releasing pools in reverse order might help avoid fragmentation
1008
* with some (brain-damaged) malloc libraries.
1010
for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
1011
free_pool(cinfo, pool);
1014
/* Release the memory manager control block too. */
1015
jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr));
1016
cinfo->mem = NULL; /* ensures I will be called only once */
1018
jpeg_mem_term(cinfo); /* system-dependent cleanup */
1023
* Memory manager initialization.
1024
* When this is called, only the error manager pointer is valid in cinfo!
1028
jinit_memory_mgr (j_common_ptr cinfo)
1035
cinfo->mem = NULL; /* for safety if init fails */
1037
/* Check for configuration errors.
1038
* SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably
1039
* doesn't reflect any real hardware alignment requirement.
1040
* The test is a little tricky: for X>0, X and X-1 have no one-bits
1041
* in common if and only if X is a power of 2, ie has only one one-bit.
1042
* Some compilers may give an "unreachable code" warning here; ignore it.
1044
if ((SIZEOF(ALIGN_TYPE) & (SIZEOF(ALIGN_TYPE)-1)) != 0)
1045
ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE);
1046
/* MAX_ALLOC_CHUNK must be representable as type size_t, and must be
1047
* a multiple of SIZEOF(ALIGN_TYPE).
1048
* Again, an "unreachable code" warning may be ignored here.
1049
* But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK.
1051
test_mac = (size_t) MAX_ALLOC_CHUNK;
1052
if ((long) test_mac != MAX_ALLOC_CHUNK ||
1053
(MAX_ALLOC_CHUNK % SIZEOF(ALIGN_TYPE)) != 0)
1054
ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
1056
max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */
1058
/* Attempt to allocate memory manager's control block */
1059
mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr));
1062
jpeg_mem_term(cinfo); /* system-dependent cleanup */
1063
ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0);
1066
/* OK, fill in the method pointers */
1067
mem->pub.alloc_small = alloc_small;
1068
mem->pub.alloc_large = alloc_large;
1069
mem->pub.alloc_sarray = alloc_sarray;
1070
mem->pub.alloc_barray = alloc_barray;
1071
mem->pub.request_virt_sarray = request_virt_sarray;
1072
mem->pub.request_virt_barray = request_virt_barray;
1073
mem->pub.realize_virt_arrays = realize_virt_arrays;
1074
mem->pub.access_virt_sarray = access_virt_sarray;
1075
mem->pub.access_virt_barray = access_virt_barray;
1076
mem->pub.free_pool = free_pool;
1077
mem->pub.self_destruct = self_destruct;
1079
/* Initialize working state */
1080
mem->pub.max_memory_to_use = max_to_use;
1082
for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
1083
mem->small_list[pool] = NULL;
1084
mem->large_list[pool] = NULL;
1086
mem->virt_sarray_list = NULL;
1087
mem->virt_barray_list = NULL;
1089
mem->total_space_allocated = SIZEOF(my_memory_mgr);
1091
/* Declare ourselves open for business */
1092
cinfo->mem = & mem->pub;
1094
/* Check for an environment variable JPEGMEM; if found, override the
1095
* default max_memory setting from jpeg_mem_init. Note that the
1096
* surrounding application may again override this value.
1097
* If your system doesn't support getenv(), define NO_GETENV to disable
1103
if ((memenv = getenv("JPEGMEM")) != NULL) {
1106
if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) {
1107
if (ch == 'm' || ch == 'M')
1108
max_to_use *= 1000L;
1109
mem->pub.max_memory_to_use = max_to_use * 1000L;
added
removed
code/jpeg-6/jmemmgr.c
