1 : /*
2 : * jmemmgr.c
3 : *
4 : * Copyright (C) 1991-1997, 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.
7 : *
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
14 : * virtual arrays;
15 : * * control logic for swapping virtual arrays between main memory and
16 : * backing storage.
17 : * The separate system-dependent file provides the actual backing-storage
18 : * access code, and it contains the policy decision about how much total
19 : * main memory to use.
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...)
25 : */
26 :
27 : #define JPEG_INTERNALS
28 : #define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */
29 : #include "jinclude.h"
30 : #include "jpeglib.h"
31 : #include "jmemsys.h" /* import the system-dependent declarations */
32 :
33 : #ifndef NO_GETENV
34 : #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare getenv() */
35 : extern char * getenv JPP((const char * name));
36 : #endif
37 : #endif
38 :
39 :
40 : LOCAL(size_t)
41 373 : round_up_pow2 (size_t a, size_t b)
42 : /* a rounded up to the next multiple of b, i.e. ceil(a/b)*b */
43 : /* Assumes a >= 0, b > 0, and b is a power of 2 */
44 : {
45 373 : return ((a + b - 1) & (~(b - 1)));
46 : }
47 :
48 :
49 : /*
50 : * Some important notes:
51 : * The allocation routines provided here must never return NULL.
52 : * They should exit to error_exit if unsuccessful.
53 : *
54 : * It's not a good idea to try to merge the sarray and barray routines,
55 : * even though they are textually almost the same, because samples are
56 : * usually stored as bytes while coefficients are shorts or ints. Thus,
57 : * in machines where byte pointers have a different representation from
58 : * word pointers, the resulting machine code could not be the same.
59 : */
60 :
61 :
62 : /*
63 : * Many machines require storage alignment: longs must start on 4-byte
64 : * boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc()
65 : * always returns pointers that are multiples of the worst-case alignment
66 : * requirement, and we had better do so too.
67 : * There isn't any really portable way to determine the worst-case alignment
68 : * requirement. This module assumes that the alignment requirement is
69 : * multiples of ALIGN_SIZE.
70 : * By default, we define ALIGN_SIZE as sizeof(double). This is necessary on some
71 : * workstations (where doubles really do need 8-byte alignment) and will work
72 : * fine on nearly everything. If your machine has lesser alignment needs,
73 : * you can save a few bytes by making ALIGN_SIZE smaller.
74 : * The only place I know of where this will NOT work is certain Macintosh
75 : * 680x0 compilers that define double as a 10-byte IEEE extended float.
76 : * Doing 10-byte alignment is counterproductive because longwords won't be
77 : * aligned well. Put "#define ALIGN_SIZE 4" in jconfig.h if you have
78 : * such a compiler.
79 : */
80 :
81 : #ifndef ALIGN_SIZE /* so can override from jconfig.h */
82 : #ifndef WITH_SIMD
83 : #define ALIGN_SIZE SIZEOF(double)
84 : #else
85 : #define ALIGN_SIZE 16 /* Most SIMD implementations require this */
86 : #endif
87 : #endif
88 :
89 : /*
90 : * We allocate objects from "pools", where each pool is gotten with a single
91 : * request to jpeg_get_small() or jpeg_get_large(). There is no per-object
92 : * overhead within a pool, except for alignment padding. Each pool has a
93 : * header with a link to the next pool of the same class.
94 : * Small and large pool headers are identical except that the latter's
95 : * link pointer must be FAR on 80x86 machines.
96 : */
97 :
98 : typedef struct small_pool_struct * small_pool_ptr;
99 :
100 : typedef struct small_pool_struct {
101 : small_pool_ptr next; /* next in list of pools */
102 : size_t bytes_used; /* how many bytes already used within pool */
103 : size_t bytes_left; /* bytes still available in this pool */
104 : } small_pool_hdr;
105 :
106 : typedef struct large_pool_struct FAR * large_pool_ptr;
107 :
108 : typedef struct large_pool_struct {
109 : large_pool_ptr next; /* next in list of pools */
110 : size_t bytes_used; /* how many bytes already used within pool */
111 : size_t bytes_left; /* bytes still available in this pool */
112 : } large_pool_hdr;
113 :
114 : /*
115 : * Here is the full definition of a memory manager object.
116 : */
117 :
118 : typedef struct {
119 : struct jpeg_memory_mgr pub; /* public fields */
120 :
121 : /* Each pool identifier (lifetime class) names a linked list of pools. */
122 : small_pool_ptr small_list[JPOOL_NUMPOOLS];
123 : large_pool_ptr large_list[JPOOL_NUMPOOLS];
124 :
125 : /* Since we only have one lifetime class of virtual arrays, only one
126 : * linked list is necessary (for each datatype). Note that the virtual
127 : * array control blocks being linked together are actually stored somewhere
128 : * in the small-pool list.
129 : */
130 : jvirt_sarray_ptr virt_sarray_list;
131 : jvirt_barray_ptr virt_barray_list;
132 :
133 : /* This counts total space obtained from jpeg_get_small/large */
134 : size_t total_space_allocated;
135 :
136 : /* alloc_sarray and alloc_barray set this value for use by virtual
137 : * array routines.
138 : */
139 : JDIMENSION last_rowsperchunk; /* from most recent alloc_sarray/barray */
140 : } my_memory_mgr;
141 :
142 : typedef my_memory_mgr * my_mem_ptr;
143 :
144 :
145 : /*
146 : * The control blocks for virtual arrays.
147 : * Note that these blocks are allocated in the "small" pool area.
148 : * System-dependent info for the associated backing store (if any) is hidden
149 : * inside the backing_store_info struct.
150 : */
151 :
152 : struct jvirt_sarray_control {
153 : JSAMPARRAY mem_buffer; /* => the in-memory buffer */
154 : JDIMENSION rows_in_array; /* total virtual array height */
155 : JDIMENSION samplesperrow; /* width of array (and of memory buffer) */
156 : JDIMENSION maxaccess; /* max rows accessed by access_virt_sarray */
157 : JDIMENSION rows_in_mem; /* height of memory buffer */
158 : JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
159 : JDIMENSION cur_start_row; /* first logical row # in the buffer */
160 : JDIMENSION first_undef_row; /* row # of first uninitialized row */
161 : boolean pre_zero; /* pre-zero mode requested? */
162 : boolean dirty; /* do current buffer contents need written? */
163 : boolean b_s_open; /* is backing-store data valid? */
164 : jvirt_sarray_ptr next; /* link to next virtual sarray control block */
165 : backing_store_info b_s_info; /* System-dependent control info */
166 : };
167 :
168 : struct jvirt_barray_control {
169 : JBLOCKARRAY mem_buffer; /* => the in-memory buffer */
170 : JDIMENSION rows_in_array; /* total virtual array height */
171 : JDIMENSION blocksperrow; /* width of array (and of memory buffer) */
172 : JDIMENSION maxaccess; /* max rows accessed by access_virt_barray */
173 : JDIMENSION rows_in_mem; /* height of memory buffer */
174 : JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
175 : JDIMENSION cur_start_row; /* first logical row # in the buffer */
176 : JDIMENSION first_undef_row; /* row # of first uninitialized row */
177 : boolean pre_zero; /* pre-zero mode requested? */
178 : boolean dirty; /* do current buffer contents need written? */
179 : boolean b_s_open; /* is backing-store data valid? */
180 : jvirt_barray_ptr next; /* link to next virtual barray control block */
181 : backing_store_info b_s_info; /* System-dependent control info */
182 : };
183 :
184 :
185 : #ifdef MEM_STATS /* optional extra stuff for statistics */
186 :
187 : LOCAL(void)
188 : print_mem_stats (j_common_ptr cinfo, int pool_id)
189 : {
190 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
191 : small_pool_ptr shdr_ptr;
192 : large_pool_ptr lhdr_ptr;
193 :
194 : /* Since this is only a debugging stub, we can cheat a little by using
195 : * fprintf directly rather than going through the trace message code.
196 : * This is helpful because message parm array can't handle longs.
197 : */
198 : fprintf(stderr, "Freeing pool %d, total space = %ld\n",
199 : pool_id, mem->total_space_allocated);
200 :
201 : for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL;
202 : lhdr_ptr = lhdr_ptr->next) {
203 : fprintf(stderr, " Large chunk used %ld\n",
204 : (long) lhdr_ptr->bytes_used);
205 : }
206 :
207 : for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL;
208 : shdr_ptr = shdr_ptr->next) {
209 : fprintf(stderr, " Small chunk used %ld free %ld\n",
210 : (long) shdr_ptr->bytes_used,
211 : (long) shdr_ptr->bytes_left);
212 : }
213 : }
214 :
215 : #endif /* MEM_STATS */
216 :
217 :
218 : LOCAL(void)
219 0 : out_of_memory (j_common_ptr cinfo, int which)
220 : /* Report an out-of-memory error and stop execution */
221 : /* If we compiled MEM_STATS support, report alloc requests before dying */
222 : {
223 : #ifdef MEM_STATS
224 : cinfo->err->trace_level = 2; /* force self_destruct to report stats */
225 : #endif
226 0 : ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which);
227 0 : }
228 :
229 :
230 : /*
231 : * Allocation of "small" objects.
232 : *
233 : * For these, we use pooled storage. When a new pool must be created,
234 : * we try to get enough space for the current request plus a "slop" factor,
235 : * where the slop will be the amount of leftover space in the new pool.
236 : * The speed vs. space tradeoff is largely determined by the slop values.
237 : * A different slop value is provided for each pool class (lifetime),
238 : * and we also distinguish the first pool of a class from later ones.
239 : * NOTE: the values given work fairly well on both 16- and 32-bit-int
240 : * machines, but may be too small if longs are 64 bits or more.
241 : *
242 : * Since we do not know what alignment malloc() gives us, we have to
243 : * allocate ALIGN_SIZE-1 extra space per pool to have room for alignment
244 : * adjustment.
245 : */
246 :
247 : static const size_t first_pool_slop[JPOOL_NUMPOOLS] =
248 : {
249 : 1600, /* first PERMANENT pool */
250 : 16000 /* first IMAGE pool */
251 : };
252 :
253 : static const size_t extra_pool_slop[JPOOL_NUMPOOLS] =
254 : {
255 : 0, /* additional PERMANENT pools */
256 : 5000 /* additional IMAGE pools */
257 : };
258 :
259 : #define MIN_SLOP 50 /* greater than 0 to avoid futile looping */
260 :
261 :
262 : METHODDEF(void *)
263 269 : alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
264 : /* Allocate a "small" object */
265 : {
266 269 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
267 : small_pool_ptr hdr_ptr, prev_hdr_ptr;
268 : char * data_ptr;
269 : size_t min_request, slop;
270 :
271 : /*
272 : * Round up the requested size to a multiple of ALIGN_SIZE in order
273 : * to assure alignment for the next object allocated in the same pool
274 : * and so that algorithms can straddle outside the proper area up
275 : * to the next alignment.
276 : */
277 269 : sizeofobject = round_up_pow2(sizeofobject, ALIGN_SIZE);
278 :
279 : /* Check for unsatisfiable request (do now to ensure no overflow below) */
280 269 : if ((SIZEOF(small_pool_hdr) + sizeofobject + ALIGN_SIZE - 1) > MAX_ALLOC_CHUNK)
281 0 : out_of_memory(cinfo, 1); /* request exceeds malloc's ability */
282 :
283 : /* See if space is available in any existing pool */
284 269 : if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
285 0 : ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
286 269 : prev_hdr_ptr = NULL;
287 269 : hdr_ptr = mem->small_list[pool_id];
288 538 : while (hdr_ptr != NULL) {
289 253 : if (hdr_ptr->bytes_left >= sizeofobject)
290 253 : break; /* found pool with enough space */
291 0 : prev_hdr_ptr = hdr_ptr;
292 0 : hdr_ptr = hdr_ptr->next;
293 : }
294 :
295 : /* Time to make a new pool? */
296 269 : if (hdr_ptr == NULL) {
297 : /* min_request is what we need now, slop is what will be leftover */
298 16 : min_request = SIZEOF(small_pool_hdr) + sizeofobject + ALIGN_SIZE - 1;
299 16 : if (prev_hdr_ptr == NULL) /* first pool in class? */
300 16 : slop = first_pool_slop[pool_id];
301 : else
302 0 : slop = extra_pool_slop[pool_id];
303 : /* Don't ask for more than MAX_ALLOC_CHUNK */
304 16 : if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request))
305 0 : slop = (size_t) (MAX_ALLOC_CHUNK-min_request);
306 : /* Try to get space, if fail reduce slop and try again */
307 : for (;;) {
308 16 : hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop);
309 16 : if (hdr_ptr != NULL)
310 : break;
311 0 : slop /= 2;
312 0 : if (slop < MIN_SLOP) /* give up when it gets real small */
313 0 : out_of_memory(cinfo, 2); /* jpeg_get_small failed */
314 0 : }
315 16 : mem->total_space_allocated += min_request + slop;
316 : /* Success, initialize the new pool header and add to end of list */
317 16 : hdr_ptr->next = NULL;
318 16 : hdr_ptr->bytes_used = 0;
319 16 : hdr_ptr->bytes_left = sizeofobject + slop;
320 16 : if (prev_hdr_ptr == NULL) /* first pool in class? */
321 16 : mem->small_list[pool_id] = hdr_ptr;
322 : else
323 0 : prev_hdr_ptr->next = hdr_ptr;
324 : }
325 :
326 : /* OK, allocate the object from the current pool */
327 269 : data_ptr = (char *) hdr_ptr; /* point to first data byte in pool... */
328 269 : data_ptr += SIZEOF(small_pool_hdr); /* ...by skipping the header... */
329 269 : if ((size_t)data_ptr % ALIGN_SIZE) /* ...and adjust for alignment */
330 269 : data_ptr += ALIGN_SIZE - (size_t)data_ptr % ALIGN_SIZE;
331 269 : data_ptr += hdr_ptr->bytes_used; /* point to place for object */
332 269 : hdr_ptr->bytes_used += sizeofobject;
333 269 : hdr_ptr->bytes_left -= sizeofobject;
334 :
335 269 : return (void *) data_ptr;
336 : }
337 :
338 :
339 : /*
340 : * Allocation of "large" objects.
341 : *
342 : * The external semantics of these are the same as "small" objects,
343 : * except that FAR pointers are used on 80x86. However the pool
344 : * management heuristics are quite different. We assume that each
345 : * request is large enough that it may as well be passed directly to
346 : * jpeg_get_large; the pool management just links everything together
347 : * so that we can free it all on demand.
348 : * Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY
349 : * structures. The routines that create these structures (see below)
350 : * deliberately bunch rows together to ensure a large request size.
351 : */
352 :
353 : METHODDEF(void FAR *)
354 61 : alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
355 : /* Allocate a "large" object */
356 : {
357 61 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
358 : large_pool_ptr hdr_ptr;
359 : char FAR * data_ptr;
360 :
361 : /*
362 : * Round up the requested size to a multiple of ALIGN_SIZE so that
363 : * algorithms can straddle outside the proper area up to the next
364 : * alignment.
365 : */
366 61 : sizeofobject = round_up_pow2(sizeofobject, ALIGN_SIZE);
367 :
368 : /* Check for unsatisfiable request (do now to ensure no overflow below) */
369 61 : if ((SIZEOF(large_pool_hdr) + sizeofobject + ALIGN_SIZE - 1) > MAX_ALLOC_CHUNK)
370 0 : out_of_memory(cinfo, 3); /* request exceeds malloc's ability */
371 :
372 : /* Always make a new pool */
373 61 : if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
374 0 : ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
375 :
376 61 : hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject +
377 : SIZEOF(large_pool_hdr) +
378 : ALIGN_SIZE - 1);
379 61 : if (hdr_ptr == NULL)
380 0 : out_of_memory(cinfo, 4); /* jpeg_get_large failed */
381 61 : mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr) + ALIGN_SIZE - 1;
382 :
383 : /* Success, initialize the new pool header and add to list */
384 61 : hdr_ptr->next = mem->large_list[pool_id];
385 : /* We maintain space counts in each pool header for statistical purposes,
386 : * even though they are not needed for allocation.
387 : */
388 61 : hdr_ptr->bytes_used = sizeofobject;
389 61 : hdr_ptr->bytes_left = 0;
390 61 : mem->large_list[pool_id] = hdr_ptr;
391 :
392 61 : data_ptr = (char *) hdr_ptr; /* point to first data byte in pool... */
393 61 : data_ptr += SIZEOF(small_pool_hdr); /* ...by skipping the header... */
394 61 : if ((size_t)data_ptr % ALIGN_SIZE) /* ...and adjust for alignment */
395 61 : data_ptr += ALIGN_SIZE - (size_t)data_ptr % ALIGN_SIZE;
396 :
397 61 : return (void FAR *) data_ptr;
398 : }
399 :
400 :
401 : /*
402 : * Creation of 2-D sample arrays.
403 : * The pointers are in near heap, the samples themselves in FAR heap.
404 : *
405 : * To minimize allocation overhead and to allow I/O of large contiguous
406 : * blocks, we allocate the sample rows in groups of as many rows as possible
407 : * without exceeding MAX_ALLOC_CHUNK total bytes per allocation request.
408 : * NB: the virtual array control routines, later in this file, know about
409 : * this chunking of rows. The rowsperchunk value is left in the mem manager
410 : * object so that it can be saved away if this sarray is the workspace for
411 : * a virtual array.
412 : *
413 : * Since we are often upsampling with a factor 2, we align the size (not
414 : * the start) to 2 * ALIGN_SIZE so that the upsampling routines don't have
415 : * to be as careful about size.
416 : */
417 :
418 : METHODDEF(JSAMPARRAY)
419 43 : alloc_sarray (j_common_ptr cinfo, int pool_id,
420 : JDIMENSION samplesperrow, JDIMENSION numrows)
421 : /* Allocate a 2-D sample array */
422 : {
423 43 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
424 : JSAMPARRAY result;
425 : JSAMPROW workspace;
426 : JDIMENSION rowsperchunk, currow, i;
427 : long ltemp;
428 :
429 : /* Make sure each row is properly aligned */
430 : if ((ALIGN_SIZE % SIZEOF(JSAMPLE)) != 0)
431 : out_of_memory(cinfo, 5); /* safety check */
432 43 : samplesperrow = (JDIMENSION)round_up_pow2(samplesperrow, (2 * ALIGN_SIZE) / SIZEOF(JSAMPLE));
433 :
434 : /* Calculate max # of rows allowed in one allocation chunk */
435 43 : ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
436 : ((long) samplesperrow * SIZEOF(JSAMPLE));
437 43 : if (ltemp <= 0)
438 0 : ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
439 43 : if (ltemp < (long) numrows)
440 0 : rowsperchunk = (JDIMENSION) ltemp;
441 : else
442 43 : rowsperchunk = numrows;
443 43 : mem->last_rowsperchunk = rowsperchunk;
444 :
445 : /* Get space for row pointers (small object) */
446 43 : result = (JSAMPARRAY) alloc_small(cinfo, pool_id,
447 : (size_t) (numrows * SIZEOF(JSAMPROW)));
448 :
449 : /* Get the rows themselves (large objects) */
450 43 : currow = 0;
451 129 : while (currow < numrows) {
452 43 : rowsperchunk = MIN(rowsperchunk, numrows - currow);
453 43 : workspace = (JSAMPROW) alloc_large(cinfo, pool_id,
454 : (size_t) ((size_t) rowsperchunk * (size_t) samplesperrow
455 : * SIZEOF(JSAMPLE)));
456 328 : for (i = rowsperchunk; i > 0; i--) {
457 285 : result[currow++] = workspace;
458 285 : workspace += samplesperrow;
459 : }
460 : }
461 :
462 43 : return result;
463 : }
464 :
465 :
466 : /*
467 : * Creation of 2-D coefficient-block arrays.
468 : * This is essentially the same as the code for sample arrays, above.
469 : */
470 :
471 : METHODDEF(JBLOCKARRAY)
472 0 : alloc_barray (j_common_ptr cinfo, int pool_id,
473 : JDIMENSION blocksperrow, JDIMENSION numrows)
474 : /* Allocate a 2-D coefficient-block array */
475 : {
476 0 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
477 : JBLOCKARRAY result;
478 : JBLOCKROW workspace;
479 : JDIMENSION rowsperchunk, currow, i;
480 : long ltemp;
481 :
482 : /* Make sure each row is properly aligned */
483 : if ((SIZEOF(JBLOCK) % ALIGN_SIZE) != 0)
484 : out_of_memory(cinfo, 6); /* safety check */
485 :
486 : /* Calculate max # of rows allowed in one allocation chunk */
487 0 : ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
488 0 : ((long) blocksperrow * SIZEOF(JBLOCK));
489 0 : if (ltemp <= 0)
490 0 : ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
491 0 : if (ltemp < (long) numrows)
492 0 : rowsperchunk = (JDIMENSION) ltemp;
493 : else
494 0 : rowsperchunk = numrows;
495 0 : mem->last_rowsperchunk = rowsperchunk;
496 :
497 : /* Get space for row pointers (small object) */
498 0 : result = (JBLOCKARRAY) alloc_small(cinfo, pool_id,
499 : (size_t) (numrows * SIZEOF(JBLOCKROW)));
500 :
501 : /* Get the rows themselves (large objects) */
502 0 : currow = 0;
503 0 : while (currow < numrows) {
504 0 : rowsperchunk = MIN(rowsperchunk, numrows - currow);
505 0 : workspace = (JBLOCKROW) alloc_large(cinfo, pool_id,
506 0 : (size_t) ((size_t) rowsperchunk * (size_t) blocksperrow
507 : * SIZEOF(JBLOCK)));
508 0 : for (i = rowsperchunk; i > 0; i--) {
509 0 : result[currow++] = workspace;
510 0 : workspace += blocksperrow;
511 : }
512 : }
513 :
514 0 : return result;
515 : }
516 :
517 :
518 : /*
519 : * About virtual array management:
520 : *
521 : * The above "normal" array routines are only used to allocate strip buffers
522 : * (as wide as the image, but just a few rows high). Full-image-sized buffers
523 : * are handled as "virtual" arrays. The array is still accessed a strip at a
524 : * time, but the memory manager must save the whole array for repeated
525 : * accesses. The intended implementation is that there is a strip buffer in
526 : * memory (as high as is possible given the desired memory limit), plus a
527 : * backing file that holds the rest of the array.
528 : *
529 : * The request_virt_array routines are told the total size of the image and
530 : * the maximum number of rows that will be accessed at once. The in-memory
531 : * buffer must be at least as large as the maxaccess value.
532 : *
533 : * The request routines create control blocks but not the in-memory buffers.
534 : * That is postponed until realize_virt_arrays is called. At that time the
535 : * total amount of space needed is known (approximately, anyway), so free
536 : * memory can be divided up fairly.
537 : *
538 : * The access_virt_array routines are responsible for making a specific strip
539 : * area accessible (after reading or writing the backing file, if necessary).
540 : * Note that the access routines are told whether the caller intends to modify
541 : * the accessed strip; during a read-only pass this saves having to rewrite
542 : * data to disk. The access routines are also responsible for pre-zeroing
543 : * any newly accessed rows, if pre-zeroing was requested.
544 : *
545 : * In current usage, the access requests are usually for nonoverlapping
546 : * strips; that is, successive access start_row numbers differ by exactly
547 : * num_rows = maxaccess. This means we can get good performance with simple
548 : * buffer dump/reload logic, by making the in-memory buffer be a multiple
549 : * of the access height; then there will never be accesses across bufferload
550 : * boundaries. The code will still work with overlapping access requests,
551 : * but it doesn't handle bufferload overlaps very efficiently.
552 : */
553 :
554 :
555 : METHODDEF(jvirt_sarray_ptr)
556 0 : request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
557 : JDIMENSION samplesperrow, JDIMENSION numrows,
558 : JDIMENSION maxaccess)
559 : /* Request a virtual 2-D sample array */
560 : {
561 0 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
562 : jvirt_sarray_ptr result;
563 :
564 : /* Only IMAGE-lifetime virtual arrays are currently supported */
565 0 : if (pool_id != JPOOL_IMAGE)
566 0 : ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
567 :
568 : /* get control block */
569 0 : result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id,
570 : SIZEOF(struct jvirt_sarray_control));
571 :
572 0 : result->mem_buffer = NULL; /* marks array not yet realized */
573 0 : result->rows_in_array = numrows;
574 0 : result->samplesperrow = samplesperrow;
575 0 : result->maxaccess = maxaccess;
576 0 : result->pre_zero = pre_zero;
577 0 : result->b_s_open = FALSE; /* no associated backing-store object */
578 0 : result->next = mem->virt_sarray_list; /* add to list of virtual arrays */
579 0 : mem->virt_sarray_list = result;
580 :
581 0 : return result;
582 : }
583 :
584 :
585 : METHODDEF(jvirt_barray_ptr)
586 0 : request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
587 : JDIMENSION blocksperrow, JDIMENSION numrows,
588 : JDIMENSION maxaccess)
589 : /* Request a virtual 2-D coefficient-block array */
590 : {
591 0 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
592 : jvirt_barray_ptr result;
593 :
594 : /* Only IMAGE-lifetime virtual arrays are currently supported */
595 0 : if (pool_id != JPOOL_IMAGE)
596 0 : ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
597 :
598 : /* get control block */
599 0 : result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id,
600 : SIZEOF(struct jvirt_barray_control));
601 :
602 0 : result->mem_buffer = NULL; /* marks array not yet realized */
603 0 : result->rows_in_array = numrows;
604 0 : result->blocksperrow = blocksperrow;
605 0 : result->maxaccess = maxaccess;
606 0 : result->pre_zero = pre_zero;
607 0 : result->b_s_open = FALSE; /* no associated backing-store object */
608 0 : result->next = mem->virt_barray_list; /* add to list of virtual arrays */
609 0 : mem->virt_barray_list = result;
610 :
611 0 : return result;
612 : }
613 :
614 :
615 : METHODDEF(void)
616 8 : realize_virt_arrays (j_common_ptr cinfo)
617 : /* Allocate the in-memory buffers for any unrealized virtual arrays */
618 : {
619 8 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
620 : size_t space_per_minheight, maximum_space, avail_mem;
621 : size_t minheights, max_minheights;
622 : jvirt_sarray_ptr sptr;
623 : jvirt_barray_ptr bptr;
624 :
625 : /* Compute the minimum space needed (maxaccess rows in each buffer)
626 : * and the maximum space needed (full image height in each buffer).
627 : * These may be of use to the system-dependent jpeg_mem_available routine.
628 : */
629 8 : space_per_minheight = 0;
630 8 : maximum_space = 0;
631 8 : for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
632 0 : if (sptr->mem_buffer == NULL) { /* if not realized yet */
633 0 : space_per_minheight += (long) sptr->maxaccess *
634 0 : (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
635 0 : maximum_space += (long) sptr->rows_in_array *
636 0 : (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
637 : }
638 : }
639 8 : for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
640 0 : if (bptr->mem_buffer == NULL) { /* if not realized yet */
641 0 : space_per_minheight += (long) bptr->maxaccess *
642 0 : (long) bptr->blocksperrow * SIZEOF(JBLOCK);
643 0 : maximum_space += (long) bptr->rows_in_array *
644 0 : (long) bptr->blocksperrow * SIZEOF(JBLOCK);
645 : }
646 : }
647 :
648 8 : if (space_per_minheight <= 0)
649 8 : return; /* no unrealized arrays, no work */
650 :
651 : /* Determine amount of memory to actually use; this is system-dependent. */
652 0 : avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space,
653 : mem->total_space_allocated);
654 :
655 : /* If the maximum space needed is available, make all the buffers full
656 : * height; otherwise parcel it out with the same number of minheights
657 : * in each buffer.
658 : */
659 0 : if (avail_mem >= maximum_space)
660 0 : max_minheights = 1000000000L;
661 : else {
662 0 : max_minheights = avail_mem / space_per_minheight;
663 : /* If there doesn't seem to be enough space, try to get the minimum
664 : * anyway. This allows a "stub" implementation of jpeg_mem_available().
665 : */
666 0 : if (max_minheights <= 0)
667 0 : max_minheights = 1;
668 : }
669 :
670 : /* Allocate the in-memory buffers and initialize backing store as needed. */
671 :
672 0 : for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
673 0 : if (sptr->mem_buffer == NULL) { /* if not realized yet */
674 0 : minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L;
675 0 : if (minheights <= max_minheights) {
676 : /* This buffer fits in memory */
677 0 : sptr->rows_in_mem = sptr->rows_in_array;
678 : } else {
679 : /* It doesn't fit in memory, create backing store. */
680 0 : sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess);
681 0 : jpeg_open_backing_store(cinfo, & sptr->b_s_info,
682 0 : (long) sptr->rows_in_array *
683 0 : (long) sptr->samplesperrow *
684 : (long) SIZEOF(JSAMPLE));
685 0 : sptr->b_s_open = TRUE;
686 : }
687 0 : sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE,
688 : sptr->samplesperrow, sptr->rows_in_mem);
689 0 : sptr->rowsperchunk = mem->last_rowsperchunk;
690 0 : sptr->cur_start_row = 0;
691 0 : sptr->first_undef_row = 0;
692 0 : sptr->dirty = FALSE;
693 : }
694 : }
695 :
696 0 : for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
697 0 : if (bptr->mem_buffer == NULL) { /* if not realized yet */
698 0 : minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L;
699 0 : if (minheights <= max_minheights) {
700 : /* This buffer fits in memory */
701 0 : bptr->rows_in_mem = bptr->rows_in_array;
702 : } else {
703 : /* It doesn't fit in memory, create backing store. */
704 0 : bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess);
705 0 : jpeg_open_backing_store(cinfo, & bptr->b_s_info,
706 0 : (long) bptr->rows_in_array *
707 0 : (long) bptr->blocksperrow *
708 : (long) SIZEOF(JBLOCK));
709 0 : bptr->b_s_open = TRUE;
710 : }
711 0 : bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE,
712 : bptr->blocksperrow, bptr->rows_in_mem);
713 0 : bptr->rowsperchunk = mem->last_rowsperchunk;
714 0 : bptr->cur_start_row = 0;
715 0 : bptr->first_undef_row = 0;
716 0 : bptr->dirty = FALSE;
717 : }
718 : }
719 : }
720 :
721 :
722 : LOCAL(void)
723 0 : do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing)
724 : /* Do backing store read or write of a virtual sample array */
725 : {
726 : long bytesperrow, file_offset, byte_count, rows, thisrow, i;
727 :
728 0 : bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE);
729 0 : file_offset = ptr->cur_start_row * bytesperrow;
730 : /* Loop to read or write each allocation chunk in mem_buffer */
731 0 : 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 0 : rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
734 : /* Transfer no more than is currently defined */
735 0 : thisrow = (long) ptr->cur_start_row + i;
736 0 : rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
737 : /* Transfer no more than fits in file */
738 0 : rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
739 0 : if (rows <= 0) /* this chunk might be past end of file! */
740 0 : break;
741 0 : byte_count = rows * bytesperrow;
742 0 : if (writing)
743 0 : (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
744 0 : (void FAR *) ptr->mem_buffer[i],
745 : file_offset, byte_count);
746 : else
747 0 : (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
748 0 : (void FAR *) ptr->mem_buffer[i],
749 : file_offset, byte_count);
750 0 : file_offset += byte_count;
751 : }
752 0 : }
753 :
754 :
755 : LOCAL(void)
756 0 : do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing)
757 : /* Do backing store read or write of a virtual coefficient-block array */
758 : {
759 : long bytesperrow, file_offset, byte_count, rows, thisrow, i;
760 :
761 0 : bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK);
762 0 : file_offset = ptr->cur_start_row * bytesperrow;
763 : /* Loop to read or write each allocation chunk in mem_buffer */
764 0 : for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
765 : /* One chunk, but check for short chunk at end of buffer */
766 0 : rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
767 : /* Transfer no more than is currently defined */
768 0 : thisrow = (long) ptr->cur_start_row + i;
769 0 : rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
770 : /* Transfer no more than fits in file */
771 0 : rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
772 0 : if (rows <= 0) /* this chunk might be past end of file! */
773 0 : break;
774 0 : byte_count = rows * bytesperrow;
775 0 : if (writing)
776 0 : (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
777 0 : (void FAR *) ptr->mem_buffer[i],
778 : file_offset, byte_count);
779 : else
780 0 : (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
781 0 : (void FAR *) ptr->mem_buffer[i],
782 : file_offset, byte_count);
783 0 : file_offset += byte_count;
784 : }
785 0 : }
786 :
787 :
788 : METHODDEF(JSAMPARRAY)
789 0 : access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
790 : JDIMENSION start_row, JDIMENSION num_rows,
791 : boolean writable)
792 : /* Access the part of a virtual sample array starting at start_row */
793 : /* and extending for num_rows rows. writable is true if */
794 : /* caller intends to modify the accessed area. */
795 : {
796 0 : JDIMENSION end_row = start_row + num_rows;
797 : JDIMENSION undef_row;
798 :
799 : /* debugging check */
800 0 : if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
801 0 : ptr->mem_buffer == NULL)
802 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
803 :
804 : /* Make the desired part of the virtual array accessible */
805 0 : if (start_row < ptr->cur_start_row ||
806 0 : end_row > ptr->cur_start_row+ptr->rows_in_mem) {
807 0 : if (! ptr->b_s_open)
808 0 : ERREXIT(cinfo, JERR_VIRTUAL_BUG);
809 : /* Flush old buffer contents if necessary */
810 0 : if (ptr->dirty) {
811 0 : do_sarray_io(cinfo, ptr, TRUE);
812 0 : ptr->dirty = FALSE;
813 : }
814 : /* Decide what part of virtual array to access.
815 : * Algorithm: if target address > current window, assume forward scan,
816 : * load starting at target address. If target address < current window,
817 : * assume backward scan, load so that target area is top of window.
818 : * Note that when switching from forward write to forward read, will have
819 : * start_row = 0, so the limiting case applies and we load from 0 anyway.
820 : */
821 0 : if (start_row > ptr->cur_start_row) {
822 0 : ptr->cur_start_row = start_row;
823 : } else {
824 : /* use long arithmetic here to avoid overflow & unsigned problems */
825 : long ltemp;
826 :
827 0 : ltemp = (long) end_row - (long) ptr->rows_in_mem;
828 0 : if (ltemp < 0)
829 0 : ltemp = 0; /* don't fall off front end of file */
830 0 : ptr->cur_start_row = (JDIMENSION) ltemp;
831 : }
832 : /* Read in the selected part of the array.
833 : * During the initial write pass, we will do no actual read
834 : * because the selected part is all undefined.
835 : */
836 0 : do_sarray_io(cinfo, ptr, FALSE);
837 : }
838 : /* Ensure the accessed part of the array is defined; prezero if needed.
839 : * To improve locality of access, we only prezero the part of the array
840 : * that the caller is about to access, not the entire in-memory array.
841 : */
842 0 : if (ptr->first_undef_row < end_row) {
843 0 : if (ptr->first_undef_row < start_row) {
844 0 : if (writable) /* writer skipped over a section of array */
845 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
846 0 : undef_row = start_row; /* but reader is allowed to read ahead */
847 : } else {
848 0 : undef_row = ptr->first_undef_row;
849 : }
850 0 : if (writable)
851 0 : ptr->first_undef_row = end_row;
852 0 : if (ptr->pre_zero) {
853 0 : size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE);
854 0 : undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
855 0 : end_row -= ptr->cur_start_row;
856 0 : while (undef_row < end_row) {
857 0 : jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
858 0 : undef_row++;
859 : }
860 : } else {
861 0 : if (! writable) /* reader looking at undefined data */
862 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
863 : }
864 : }
865 : /* Flag the buffer dirty if caller will write in it */
866 0 : if (writable)
867 0 : ptr->dirty = TRUE;
868 : /* Return address of proper part of the buffer */
869 0 : return ptr->mem_buffer + (start_row - ptr->cur_start_row);
870 : }
871 :
872 :
873 : METHODDEF(JBLOCKARRAY)
874 0 : access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr,
875 : JDIMENSION start_row, JDIMENSION num_rows,
876 : boolean writable)
877 : /* Access the part of a virtual block array starting at start_row */
878 : /* and extending for num_rows rows. writable is true if */
879 : /* caller intends to modify the accessed area. */
880 : {
881 0 : JDIMENSION end_row = start_row + num_rows;
882 : JDIMENSION undef_row;
883 :
884 : /* debugging check */
885 0 : if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
886 0 : ptr->mem_buffer == NULL)
887 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
888 :
889 : /* Make the desired part of the virtual array accessible */
890 0 : if (start_row < ptr->cur_start_row ||
891 0 : end_row > ptr->cur_start_row+ptr->rows_in_mem) {
892 0 : if (! ptr->b_s_open)
893 0 : ERREXIT(cinfo, JERR_VIRTUAL_BUG);
894 : /* Flush old buffer contents if necessary */
895 0 : if (ptr->dirty) {
896 0 : do_barray_io(cinfo, ptr, TRUE);
897 0 : ptr->dirty = FALSE;
898 : }
899 : /* Decide what part of virtual array to access.
900 : * Algorithm: if target address > current window, assume forward scan,
901 : * load starting at target address. If target address < current window,
902 : * assume backward scan, load so that target area is top of window.
903 : * Note that when switching from forward write to forward read, will have
904 : * start_row = 0, so the limiting case applies and we load from 0 anyway.
905 : */
906 0 : if (start_row > ptr->cur_start_row) {
907 0 : ptr->cur_start_row = start_row;
908 : } else {
909 : /* use long arithmetic here to avoid overflow & unsigned problems */
910 : long ltemp;
911 :
912 0 : ltemp = (long) end_row - (long) ptr->rows_in_mem;
913 0 : if (ltemp < 0)
914 0 : ltemp = 0; /* don't fall off front end of file */
915 0 : ptr->cur_start_row = (JDIMENSION) ltemp;
916 : }
917 : /* Read in the selected part of the array.
918 : * During the initial write pass, we will do no actual read
919 : * because the selected part is all undefined.
920 : */
921 0 : do_barray_io(cinfo, ptr, FALSE);
922 : }
923 : /* Ensure the accessed part of the array is defined; prezero if needed.
924 : * To improve locality of access, we only prezero the part of the array
925 : * that the caller is about to access, not the entire in-memory array.
926 : */
927 0 : if (ptr->first_undef_row < end_row) {
928 0 : if (ptr->first_undef_row < start_row) {
929 0 : if (writable) /* writer skipped over a section of array */
930 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
931 0 : undef_row = start_row; /* but reader is allowed to read ahead */
932 : } else {
933 0 : undef_row = ptr->first_undef_row;
934 : }
935 0 : if (writable)
936 0 : ptr->first_undef_row = end_row;
937 0 : if (ptr->pre_zero) {
938 0 : size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK);
939 0 : undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
940 0 : end_row -= ptr->cur_start_row;
941 0 : while (undef_row < end_row) {
942 0 : jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
943 0 : undef_row++;
944 : }
945 : } else {
946 0 : if (! writable) /* reader looking at undefined data */
947 0 : ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
948 : }
949 : }
950 : /* Flag the buffer dirty if caller will write in it */
951 0 : if (writable)
952 0 : ptr->dirty = TRUE;
953 : /* Return address of proper part of the buffer */
954 0 : return ptr->mem_buffer + (start_row - ptr->cur_start_row);
955 : }
956 :
957 :
958 : /*
959 : * Release all objects belonging to a specified pool.
960 : */
961 :
962 : METHODDEF(void)
963 24 : free_pool (j_common_ptr cinfo, int pool_id)
964 : {
965 24 : my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
966 : small_pool_ptr shdr_ptr;
967 : large_pool_ptr lhdr_ptr;
968 : size_t space_freed;
969 :
970 24 : if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
971 0 : ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
972 :
973 : #ifdef MEM_STATS
974 : if (cinfo->err->trace_level > 1)
975 : print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */
976 : #endif
977 :
978 : /* If freeing IMAGE pool, close any virtual arrays first */
979 24 : if (pool_id == JPOOL_IMAGE) {
980 : jvirt_sarray_ptr sptr;
981 : jvirt_barray_ptr bptr;
982 :
983 16 : for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
984 0 : if (sptr->b_s_open) { /* there may be no backing store */
985 0 : sptr->b_s_open = FALSE; /* prevent recursive close if error */
986 0 : (*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info);
987 : }
988 : }
989 16 : mem->virt_sarray_list = NULL;
990 16 : for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
991 0 : if (bptr->b_s_open) { /* there may be no backing store */
992 0 : bptr->b_s_open = FALSE; /* prevent recursive close if error */
993 0 : (*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info);
994 : }
995 : }
996 16 : mem->virt_barray_list = NULL;
997 : }
998 :
999 : /* Release large objects */
1000 24 : lhdr_ptr = mem->large_list[pool_id];
1001 24 : mem->large_list[pool_id] = NULL;
1002 :
1003 109 : while (lhdr_ptr != NULL) {
1004 61 : large_pool_ptr next_lhdr_ptr = lhdr_ptr->next;
1005 122 : space_freed = lhdr_ptr->bytes_used +
1006 61 : lhdr_ptr->bytes_left +
1007 : SIZEOF(large_pool_hdr);
1008 61 : jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed);
1009 61 : mem->total_space_allocated -= space_freed;
1010 61 : lhdr_ptr = next_lhdr_ptr;
1011 : }
1012 :
1013 : /* Release small objects */
1014 24 : shdr_ptr = mem->small_list[pool_id];
1015 24 : mem->small_list[pool_id] = NULL;
1016 :
1017 64 : while (shdr_ptr != NULL) {
1018 16 : small_pool_ptr next_shdr_ptr = shdr_ptr->next;
1019 32 : space_freed = shdr_ptr->bytes_used +
1020 16 : shdr_ptr->bytes_left +
1021 : SIZEOF(small_pool_hdr);
1022 16 : jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed);
1023 16 : mem->total_space_allocated -= space_freed;
1024 16 : shdr_ptr = next_shdr_ptr;
1025 : }
1026 24 : }
1027 :
1028 :
1029 : /*
1030 : * Close up shop entirely.
1031 : * Note that this cannot be called unless cinfo->mem is non-NULL.
1032 : */
1033 :
1034 : METHODDEF(void)
1035 8 : self_destruct (j_common_ptr cinfo)
1036 : {
1037 : int pool;
1038 :
1039 : /* Close all backing store, release all memory.
1040 : * Releasing pools in reverse order might help avoid fragmentation
1041 : * with some (brain-damaged) malloc libraries.
1042 : */
1043 24 : for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
1044 16 : free_pool(cinfo, pool);
1045 : }
1046 :
1047 : /* Release the memory manager control block too. */
1048 8 : jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr));
1049 8 : cinfo->mem = NULL; /* ensures I will be called only once */
1050 :
1051 8 : jpeg_mem_term(cinfo); /* system-dependent cleanup */
1052 8 : }
1053 :
1054 :
1055 : /*
1056 : * Memory manager initialization.
1057 : * When this is called, only the error manager pointer is valid in cinfo!
1058 : */
1059 :
1060 : GLOBAL(void)
1061 8 : jinit_memory_mgr (j_common_ptr cinfo)
1062 : {
1063 : my_mem_ptr mem;
1064 : long max_to_use;
1065 : int pool;
1066 : size_t test_mac;
1067 :
1068 8 : cinfo->mem = NULL; /* for safety if init fails */
1069 :
1070 : /* Check for configuration errors.
1071 : * SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably
1072 : * doesn't reflect any real hardware alignment requirement.
1073 : * The test is a little tricky: for X>0, X and X-1 have no one-bits
1074 : * in common if and only if X is a power of 2, ie has only one one-bit.
1075 : * Some compilers may give an "unreachable code" warning here; ignore it.
1076 : */
1077 : if ((ALIGN_SIZE & (ALIGN_SIZE-1)) != 0)
1078 : ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE);
1079 : /* MAX_ALLOC_CHUNK must be representable as type size_t, and must be
1080 : * a multiple of ALIGN_SIZE.
1081 : * Again, an "unreachable code" warning may be ignored here.
1082 : * But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK.
1083 : */
1084 8 : test_mac = (size_t) MAX_ALLOC_CHUNK;
1085 8 : if ((long) test_mac != MAX_ALLOC_CHUNK ||
1086 : (MAX_ALLOC_CHUNK % ALIGN_SIZE) != 0)
1087 0 : ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
1088 :
1089 8 : max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */
1090 :
1091 : /* Attempt to allocate memory manager's control block */
1092 8 : mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr));
1093 :
1094 8 : if (mem == NULL) {
1095 0 : jpeg_mem_term(cinfo); /* system-dependent cleanup */
1096 0 : ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0);
1097 : }
1098 :
1099 : /* OK, fill in the method pointers */
1100 8 : mem->pub.alloc_small = alloc_small;
1101 8 : mem->pub.alloc_large = alloc_large;
1102 8 : mem->pub.alloc_sarray = alloc_sarray;
1103 8 : mem->pub.alloc_barray = alloc_barray;
1104 8 : mem->pub.request_virt_sarray = request_virt_sarray;
1105 8 : mem->pub.request_virt_barray = request_virt_barray;
1106 8 : mem->pub.realize_virt_arrays = realize_virt_arrays;
1107 8 : mem->pub.access_virt_sarray = access_virt_sarray;
1108 8 : mem->pub.access_virt_barray = access_virt_barray;
1109 8 : mem->pub.free_pool = free_pool;
1110 8 : mem->pub.self_destruct = self_destruct;
1111 :
1112 : /* Make MAX_ALLOC_CHUNK accessible to other modules */
1113 8 : mem->pub.max_alloc_chunk = MAX_ALLOC_CHUNK;
1114 :
1115 : /* Initialize working state */
1116 8 : mem->pub.max_memory_to_use = max_to_use;
1117 :
1118 24 : for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
1119 16 : mem->small_list[pool] = NULL;
1120 16 : mem->large_list[pool] = NULL;
1121 : }
1122 8 : mem->virt_sarray_list = NULL;
1123 8 : mem->virt_barray_list = NULL;
1124 :
1125 8 : mem->total_space_allocated = SIZEOF(my_memory_mgr);
1126 :
1127 : /* Declare ourselves open for business */
1128 8 : cinfo->mem = & mem->pub;
1129 :
1130 : /* Check for an environment variable JPEGMEM; if found, override the
1131 : * default max_memory setting from jpeg_mem_init. Note that the
1132 : * surrounding application may again override this value.
1133 : * If your system doesn't support getenv(), define NO_GETENV to disable
1134 : * this feature.
1135 : */
1136 : #ifndef NO_GETENV
1137 : { char * memenv;
1138 :
1139 8 : if ((memenv = getenv("JPEGMEM")) != NULL) {
1140 0 : char ch = 'x';
1141 :
1142 0 : if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) {
1143 0 : if (ch == 'm' || ch == 'M')
1144 0 : max_to_use *= 1000L;
1145 0 : mem->pub.max_memory_to_use = max_to_use * 1000L;
1146 : }
1147 : }
1148 : }
1149 : #endif
1150 :
1151 8 : }
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