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annotate libs/libjpeg/jmemmgr.c @ 33:33e9eedad390

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ah.. blunder
author John Tsiombikas <nuclear@mutantstargoat.com>
date Fri, 09 Sep 2011 00:03:37 +0300
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nuclear@26 1 /*
nuclear@26 2 * jmemmgr.c
nuclear@26 3 *
nuclear@26 4 * Copyright (C) 1991-1997, Thomas G. Lane.
nuclear@26 5 * This file is part of the Independent JPEG Group's software.
nuclear@26 6 * For conditions of distribution and use, see the accompanying README file.
nuclear@26 7 *
nuclear@26 8 * This file contains the JPEG system-independent memory management
nuclear@26 9 * routines. This code is usable across a wide variety of machines; most
nuclear@26 10 * of the system dependencies have been isolated in a separate file.
nuclear@26 11 * The major functions provided here are:
nuclear@26 12 * * pool-based allocation and freeing of memory;
nuclear@26 13 * * policy decisions about how to divide available memory among the
nuclear@26 14 * virtual arrays;
nuclear@26 15 * * control logic for swapping virtual arrays between main memory and
nuclear@26 16 * backing storage.
nuclear@26 17 * The separate system-dependent file provides the actual backing-storage
nuclear@26 18 * access code, and it contains the policy decision about how much total
nuclear@26 19 * main memory to use.
nuclear@26 20 * This file is system-dependent in the sense that some of its functions
nuclear@26 21 * are unnecessary in some systems. For example, if there is enough virtual
nuclear@26 22 * memory so that backing storage will never be used, much of the virtual
nuclear@26 23 * array control logic could be removed. (Of course, if you have that much
nuclear@26 24 * memory then you shouldn't care about a little bit of unused code...)
nuclear@26 25 */
nuclear@26 26
nuclear@26 27 #define JPEG_INTERNALS
nuclear@26 28 #define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */
nuclear@26 29 #include "jinclude.h"
nuclear@26 30 #include "jpeglib.h"
nuclear@26 31 #include "jmemsys.h" /* import the system-dependent declarations */
nuclear@26 32
nuclear@26 33 #ifndef NO_GETENV
nuclear@26 34 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare getenv() */
nuclear@26 35 extern char * getenv JPP((const char * name));
nuclear@26 36 #endif
nuclear@26 37 #endif
nuclear@26 38
nuclear@26 39
nuclear@26 40 /*
nuclear@26 41 * Some important notes:
nuclear@26 42 * The allocation routines provided here must never return NULL.
nuclear@26 43 * They should exit to error_exit if unsuccessful.
nuclear@26 44 *
nuclear@26 45 * It's not a good idea to try to merge the sarray and barray routines,
nuclear@26 46 * even though they are textually almost the same, because samples are
nuclear@26 47 * usually stored as bytes while coefficients are shorts or ints. Thus,
nuclear@26 48 * in machines where byte pointers have a different representation from
nuclear@26 49 * word pointers, the resulting machine code could not be the same.
nuclear@26 50 */
nuclear@26 51
nuclear@26 52
nuclear@26 53 /*
nuclear@26 54 * Many machines require storage alignment: longs must start on 4-byte
nuclear@26 55 * boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc()
nuclear@26 56 * always returns pointers that are multiples of the worst-case alignment
nuclear@26 57 * requirement, and we had better do so too.
nuclear@26 58 * There isn't any really portable way to determine the worst-case alignment
nuclear@26 59 * requirement. This module assumes that the alignment requirement is
nuclear@26 60 * multiples of sizeof(ALIGN_TYPE).
nuclear@26 61 * By default, we define ALIGN_TYPE as double. This is necessary on some
nuclear@26 62 * workstations (where doubles really do need 8-byte alignment) and will work
nuclear@26 63 * fine on nearly everything. If your machine has lesser alignment needs,
nuclear@26 64 * you can save a few bytes by making ALIGN_TYPE smaller.
nuclear@26 65 * The only place I know of where this will NOT work is certain Macintosh
nuclear@26 66 * 680x0 compilers that define double as a 10-byte IEEE extended float.
nuclear@26 67 * Doing 10-byte alignment is counterproductive because longwords won't be
nuclear@26 68 * aligned well. Put "#define ALIGN_TYPE long" in jconfig.h if you have
nuclear@26 69 * such a compiler.
nuclear@26 70 */
nuclear@26 71
nuclear@26 72 #ifndef ALIGN_TYPE /* so can override from jconfig.h */
nuclear@26 73 #define ALIGN_TYPE double
nuclear@26 74 #endif
nuclear@26 75
nuclear@26 76
nuclear@26 77 /*
nuclear@26 78 * We allocate objects from "pools", where each pool is gotten with a single
nuclear@26 79 * request to jpeg_get_small() or jpeg_get_large(). There is no per-object
nuclear@26 80 * overhead within a pool, except for alignment padding. Each pool has a
nuclear@26 81 * header with a link to the next pool of the same class.
nuclear@26 82 * Small and large pool headers are identical except that the latter's
nuclear@26 83 * link pointer must be FAR on 80x86 machines.
nuclear@26 84 * Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE
nuclear@26 85 * field. This forces the compiler to make SIZEOF(small_pool_hdr) a multiple
nuclear@26 86 * of the alignment requirement of ALIGN_TYPE.
nuclear@26 87 */
nuclear@26 88
nuclear@26 89 typedef union small_pool_struct * small_pool_ptr;
nuclear@26 90
nuclear@26 91 typedef union small_pool_struct {
nuclear@26 92 struct {
nuclear@26 93 small_pool_ptr next; /* next in list of pools */
nuclear@26 94 size_t bytes_used; /* how many bytes already used within pool */
nuclear@26 95 size_t bytes_left; /* bytes still available in this pool */
nuclear@26 96 } hdr;
nuclear@26 97 ALIGN_TYPE dummy; /* included in union to ensure alignment */
nuclear@26 98 } small_pool_hdr;
nuclear@26 99
nuclear@26 100 typedef union large_pool_struct FAR * large_pool_ptr;
nuclear@26 101
nuclear@26 102 typedef union large_pool_struct {
nuclear@26 103 struct {
nuclear@26 104 large_pool_ptr next; /* next in list of pools */
nuclear@26 105 size_t bytes_used; /* how many bytes already used within pool */
nuclear@26 106 size_t bytes_left; /* bytes still available in this pool */
nuclear@26 107 } hdr;
nuclear@26 108 ALIGN_TYPE dummy; /* included in union to ensure alignment */
nuclear@26 109 } large_pool_hdr;
nuclear@26 110
nuclear@26 111
nuclear@26 112 /*
nuclear@26 113 * Here is the full definition of a memory manager object.
nuclear@26 114 */
nuclear@26 115
nuclear@26 116 typedef struct {
nuclear@26 117 struct jpeg_memory_mgr pub; /* public fields */
nuclear@26 118
nuclear@26 119 /* Each pool identifier (lifetime class) names a linked list of pools. */
nuclear@26 120 small_pool_ptr small_list[JPOOL_NUMPOOLS];
nuclear@26 121 large_pool_ptr large_list[JPOOL_NUMPOOLS];
nuclear@26 122
nuclear@26 123 /* Since we only have one lifetime class of virtual arrays, only one
nuclear@26 124 * linked list is necessary (for each datatype). Note that the virtual
nuclear@26 125 * array control blocks being linked together are actually stored somewhere
nuclear@26 126 * in the small-pool list.
nuclear@26 127 */
nuclear@26 128 jvirt_sarray_ptr virt_sarray_list;
nuclear@26 129 jvirt_barray_ptr virt_barray_list;
nuclear@26 130
nuclear@26 131 /* This counts total space obtained from jpeg_get_small/large */
nuclear@26 132 long total_space_allocated;
nuclear@26 133
nuclear@26 134 /* alloc_sarray and alloc_barray set this value for use by virtual
nuclear@26 135 * array routines.
nuclear@26 136 */
nuclear@26 137 JDIMENSION last_rowsperchunk; /* from most recent alloc_sarray/barray */
nuclear@26 138 } my_memory_mgr;
nuclear@26 139
nuclear@26 140 typedef my_memory_mgr * my_mem_ptr;
nuclear@26 141
nuclear@26 142
nuclear@26 143 /*
nuclear@26 144 * The control blocks for virtual arrays.
nuclear@26 145 * Note that these blocks are allocated in the "small" pool area.
nuclear@26 146 * System-dependent info for the associated backing store (if any) is hidden
nuclear@26 147 * inside the backing_store_info struct.
nuclear@26 148 */
nuclear@26 149
nuclear@26 150 struct jvirt_sarray_control {
nuclear@26 151 JSAMPARRAY mem_buffer; /* => the in-memory buffer */
nuclear@26 152 JDIMENSION rows_in_array; /* total virtual array height */
nuclear@26 153 JDIMENSION samplesperrow; /* width of array (and of memory buffer) */
nuclear@26 154 JDIMENSION maxaccess; /* max rows accessed by access_virt_sarray */
nuclear@26 155 JDIMENSION rows_in_mem; /* height of memory buffer */
nuclear@26 156 JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
nuclear@26 157 JDIMENSION cur_start_row; /* first logical row # in the buffer */
nuclear@26 158 JDIMENSION first_undef_row; /* row # of first uninitialized row */
nuclear@26 159 boolean pre_zero; /* pre-zero mode requested? */
nuclear@26 160 boolean dirty; /* do current buffer contents need written? */
nuclear@26 161 boolean b_s_open; /* is backing-store data valid? */
nuclear@26 162 jvirt_sarray_ptr next; /* link to next virtual sarray control block */
nuclear@26 163 backing_store_info b_s_info; /* System-dependent control info */
nuclear@26 164 };
nuclear@26 165
nuclear@26 166 struct jvirt_barray_control {
nuclear@26 167 JBLOCKARRAY mem_buffer; /* => the in-memory buffer */
nuclear@26 168 JDIMENSION rows_in_array; /* total virtual array height */
nuclear@26 169 JDIMENSION blocksperrow; /* width of array (and of memory buffer) */
nuclear@26 170 JDIMENSION maxaccess; /* max rows accessed by access_virt_barray */
nuclear@26 171 JDIMENSION rows_in_mem; /* height of memory buffer */
nuclear@26 172 JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
nuclear@26 173 JDIMENSION cur_start_row; /* first logical row # in the buffer */
nuclear@26 174 JDIMENSION first_undef_row; /* row # of first uninitialized row */
nuclear@26 175 boolean pre_zero; /* pre-zero mode requested? */
nuclear@26 176 boolean dirty; /* do current buffer contents need written? */
nuclear@26 177 boolean b_s_open; /* is backing-store data valid? */
nuclear@26 178 jvirt_barray_ptr next; /* link to next virtual barray control block */
nuclear@26 179 backing_store_info b_s_info; /* System-dependent control info */
nuclear@26 180 };
nuclear@26 181
nuclear@26 182
nuclear@26 183 #ifdef MEM_STATS /* optional extra stuff for statistics */
nuclear@26 184
nuclear@26 185 LOCAL(void)
nuclear@26 186 print_mem_stats (j_common_ptr cinfo, int pool_id)
nuclear@26 187 {
nuclear@26 188 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 189 small_pool_ptr shdr_ptr;
nuclear@26 190 large_pool_ptr lhdr_ptr;
nuclear@26 191
nuclear@26 192 /* Since this is only a debugging stub, we can cheat a little by using
nuclear@26 193 * fprintf directly rather than going through the trace message code.
nuclear@26 194 * This is helpful because message parm array can't handle longs.
nuclear@26 195 */
nuclear@26 196 fprintf(stderr, "Freeing pool %d, total space = %ld\n",
nuclear@26 197 pool_id, mem->total_space_allocated);
nuclear@26 198
nuclear@26 199 for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL;
nuclear@26 200 lhdr_ptr = lhdr_ptr->hdr.next) {
nuclear@26 201 fprintf(stderr, " Large chunk used %ld\n",
nuclear@26 202 (long) lhdr_ptr->hdr.bytes_used);
nuclear@26 203 }
nuclear@26 204
nuclear@26 205 for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL;
nuclear@26 206 shdr_ptr = shdr_ptr->hdr.next) {
nuclear@26 207 fprintf(stderr, " Small chunk used %ld free %ld\n",
nuclear@26 208 (long) shdr_ptr->hdr.bytes_used,
nuclear@26 209 (long) shdr_ptr->hdr.bytes_left);
nuclear@26 210 }
nuclear@26 211 }
nuclear@26 212
nuclear@26 213 #endif /* MEM_STATS */
nuclear@26 214
nuclear@26 215
nuclear@26 216 LOCAL(void)
nuclear@26 217 out_of_memory (j_common_ptr cinfo, int which)
nuclear@26 218 /* Report an out-of-memory error and stop execution */
nuclear@26 219 /* If we compiled MEM_STATS support, report alloc requests before dying */
nuclear@26 220 {
nuclear@26 221 #ifdef MEM_STATS
nuclear@26 222 cinfo->err->trace_level = 2; /* force self_destruct to report stats */
nuclear@26 223 #endif
nuclear@26 224 ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which);
nuclear@26 225 }
nuclear@26 226
nuclear@26 227
nuclear@26 228 /*
nuclear@26 229 * Allocation of "small" objects.
nuclear@26 230 *
nuclear@26 231 * For these, we use pooled storage. When a new pool must be created,
nuclear@26 232 * we try to get enough space for the current request plus a "slop" factor,
nuclear@26 233 * where the slop will be the amount of leftover space in the new pool.
nuclear@26 234 * The speed vs. space tradeoff is largely determined by the slop values.
nuclear@26 235 * A different slop value is provided for each pool class (lifetime),
nuclear@26 236 * and we also distinguish the first pool of a class from later ones.
nuclear@26 237 * NOTE: the values given work fairly well on both 16- and 32-bit-int
nuclear@26 238 * machines, but may be too small if longs are 64 bits or more.
nuclear@26 239 */
nuclear@26 240
nuclear@26 241 static const size_t first_pool_slop[JPOOL_NUMPOOLS] =
nuclear@26 242 {
nuclear@26 243 1600, /* first PERMANENT pool */
nuclear@26 244 16000 /* first IMAGE pool */
nuclear@26 245 };
nuclear@26 246
nuclear@26 247 static const size_t extra_pool_slop[JPOOL_NUMPOOLS] =
nuclear@26 248 {
nuclear@26 249 0, /* additional PERMANENT pools */
nuclear@26 250 5000 /* additional IMAGE pools */
nuclear@26 251 };
nuclear@26 252
nuclear@26 253 #define MIN_SLOP 50 /* greater than 0 to avoid futile looping */
nuclear@26 254
nuclear@26 255
nuclear@26 256 METHODDEF(void *)
nuclear@26 257 alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
nuclear@26 258 /* Allocate a "small" object */
nuclear@26 259 {
nuclear@26 260 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 261 small_pool_ptr hdr_ptr, prev_hdr_ptr;
nuclear@26 262 char * data_ptr;
nuclear@26 263 size_t odd_bytes, min_request, slop;
nuclear@26 264
nuclear@26 265 /* Check for unsatisfiable request (do now to ensure no overflow below) */
nuclear@26 266 if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(small_pool_hdr)))
nuclear@26 267 out_of_memory(cinfo, 1); /* request exceeds malloc's ability */
nuclear@26 268
nuclear@26 269 /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
nuclear@26 270 odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
nuclear@26 271 if (odd_bytes > 0)
nuclear@26 272 sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
nuclear@26 273
nuclear@26 274 /* See if space is available in any existing pool */
nuclear@26 275 if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
nuclear@26 276 ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
nuclear@26 277 prev_hdr_ptr = NULL;
nuclear@26 278 hdr_ptr = mem->small_list[pool_id];
nuclear@26 279 while (hdr_ptr != NULL) {
nuclear@26 280 if (hdr_ptr->hdr.bytes_left >= sizeofobject)
nuclear@26 281 break; /* found pool with enough space */
nuclear@26 282 prev_hdr_ptr = hdr_ptr;
nuclear@26 283 hdr_ptr = hdr_ptr->hdr.next;
nuclear@26 284 }
nuclear@26 285
nuclear@26 286 /* Time to make a new pool? */
nuclear@26 287 if (hdr_ptr == NULL) {
nuclear@26 288 /* min_request is what we need now, slop is what will be leftover */
nuclear@26 289 min_request = sizeofobject + SIZEOF(small_pool_hdr);
nuclear@26 290 if (prev_hdr_ptr == NULL) /* first pool in class? */
nuclear@26 291 slop = first_pool_slop[pool_id];
nuclear@26 292 else
nuclear@26 293 slop = extra_pool_slop[pool_id];
nuclear@26 294 /* Don't ask for more than MAX_ALLOC_CHUNK */
nuclear@26 295 if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request))
nuclear@26 296 slop = (size_t) (MAX_ALLOC_CHUNK-min_request);
nuclear@26 297 /* Try to get space, if fail reduce slop and try again */
nuclear@26 298 for (;;) {
nuclear@26 299 hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop);
nuclear@26 300 if (hdr_ptr != NULL)
nuclear@26 301 break;
nuclear@26 302 slop /= 2;
nuclear@26 303 if (slop < MIN_SLOP) /* give up when it gets real small */
nuclear@26 304 out_of_memory(cinfo, 2); /* jpeg_get_small failed */
nuclear@26 305 }
nuclear@26 306 mem->total_space_allocated += min_request + slop;
nuclear@26 307 /* Success, initialize the new pool header and add to end of list */
nuclear@26 308 hdr_ptr->hdr.next = NULL;
nuclear@26 309 hdr_ptr->hdr.bytes_used = 0;
nuclear@26 310 hdr_ptr->hdr.bytes_left = sizeofobject + slop;
nuclear@26 311 if (prev_hdr_ptr == NULL) /* first pool in class? */
nuclear@26 312 mem->small_list[pool_id] = hdr_ptr;
nuclear@26 313 else
nuclear@26 314 prev_hdr_ptr->hdr.next = hdr_ptr;
nuclear@26 315 }
nuclear@26 316
nuclear@26 317 /* OK, allocate the object from the current pool */
nuclear@26 318 data_ptr = (char *) (hdr_ptr + 1); /* point to first data byte in pool */
nuclear@26 319 data_ptr += hdr_ptr->hdr.bytes_used; /* point to place for object */
nuclear@26 320 hdr_ptr->hdr.bytes_used += sizeofobject;
nuclear@26 321 hdr_ptr->hdr.bytes_left -= sizeofobject;
nuclear@26 322
nuclear@26 323 return (void *) data_ptr;
nuclear@26 324 }
nuclear@26 325
nuclear@26 326
nuclear@26 327 /*
nuclear@26 328 * Allocation of "large" objects.
nuclear@26 329 *
nuclear@26 330 * The external semantics of these are the same as "small" objects,
nuclear@26 331 * except that FAR pointers are used on 80x86. However the pool
nuclear@26 332 * management heuristics are quite different. We assume that each
nuclear@26 333 * request is large enough that it may as well be passed directly to
nuclear@26 334 * jpeg_get_large; the pool management just links everything together
nuclear@26 335 * so that we can free it all on demand.
nuclear@26 336 * Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY
nuclear@26 337 * structures. The routines that create these structures (see below)
nuclear@26 338 * deliberately bunch rows together to ensure a large request size.
nuclear@26 339 */
nuclear@26 340
nuclear@26 341 METHODDEF(void FAR *)
nuclear@26 342 alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
nuclear@26 343 /* Allocate a "large" object */
nuclear@26 344 {
nuclear@26 345 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 346 large_pool_ptr hdr_ptr;
nuclear@26 347 size_t odd_bytes;
nuclear@26 348
nuclear@26 349 /* Check for unsatisfiable request (do now to ensure no overflow below) */
nuclear@26 350 if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)))
nuclear@26 351 out_of_memory(cinfo, 3); /* request exceeds malloc's ability */
nuclear@26 352
nuclear@26 353 /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
nuclear@26 354 odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
nuclear@26 355 if (odd_bytes > 0)
nuclear@26 356 sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
nuclear@26 357
nuclear@26 358 /* Always make a new pool */
nuclear@26 359 if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
nuclear@26 360 ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
nuclear@26 361
nuclear@26 362 hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject +
nuclear@26 363 SIZEOF(large_pool_hdr));
nuclear@26 364 if (hdr_ptr == NULL)
nuclear@26 365 out_of_memory(cinfo, 4); /* jpeg_get_large failed */
nuclear@26 366 mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr);
nuclear@26 367
nuclear@26 368 /* Success, initialize the new pool header and add to list */
nuclear@26 369 hdr_ptr->hdr.next = mem->large_list[pool_id];
nuclear@26 370 /* We maintain space counts in each pool header for statistical purposes,
nuclear@26 371 * even though they are not needed for allocation.
nuclear@26 372 */
nuclear@26 373 hdr_ptr->hdr.bytes_used = sizeofobject;
nuclear@26 374 hdr_ptr->hdr.bytes_left = 0;
nuclear@26 375 mem->large_list[pool_id] = hdr_ptr;
nuclear@26 376
nuclear@26 377 return (void FAR *) (hdr_ptr + 1); /* point to first data byte in pool */
nuclear@26 378 }
nuclear@26 379
nuclear@26 380
nuclear@26 381 /*
nuclear@26 382 * Creation of 2-D sample arrays.
nuclear@26 383 * The pointers are in near heap, the samples themselves in FAR heap.
nuclear@26 384 *
nuclear@26 385 * To minimize allocation overhead and to allow I/O of large contiguous
nuclear@26 386 * blocks, we allocate the sample rows in groups of as many rows as possible
nuclear@26 387 * without exceeding MAX_ALLOC_CHUNK total bytes per allocation request.
nuclear@26 388 * NB: the virtual array control routines, later in this file, know about
nuclear@26 389 * this chunking of rows. The rowsperchunk value is left in the mem manager
nuclear@26 390 * object so that it can be saved away if this sarray is the workspace for
nuclear@26 391 * a virtual array.
nuclear@26 392 */
nuclear@26 393
nuclear@26 394 METHODDEF(JSAMPARRAY)
nuclear@26 395 alloc_sarray (j_common_ptr cinfo, int pool_id,
nuclear@26 396 JDIMENSION samplesperrow, JDIMENSION numrows)
nuclear@26 397 /* Allocate a 2-D sample array */
nuclear@26 398 {
nuclear@26 399 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 400 JSAMPARRAY result;
nuclear@26 401 JSAMPROW workspace;
nuclear@26 402 JDIMENSION rowsperchunk, currow, i;
nuclear@26 403 long ltemp;
nuclear@26 404
nuclear@26 405 /* Calculate max # of rows allowed in one allocation chunk */
nuclear@26 406 ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
nuclear@26 407 ((long) samplesperrow * SIZEOF(JSAMPLE));
nuclear@26 408 if (ltemp <= 0)
nuclear@26 409 ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
nuclear@26 410 if (ltemp < (long) numrows)
nuclear@26 411 rowsperchunk = (JDIMENSION) ltemp;
nuclear@26 412 else
nuclear@26 413 rowsperchunk = numrows;
nuclear@26 414 mem->last_rowsperchunk = rowsperchunk;
nuclear@26 415
nuclear@26 416 /* Get space for row pointers (small object) */
nuclear@26 417 result = (JSAMPARRAY) alloc_small(cinfo, pool_id,
nuclear@26 418 (size_t) (numrows * SIZEOF(JSAMPROW)));
nuclear@26 419
nuclear@26 420 /* Get the rows themselves (large objects) */
nuclear@26 421 currow = 0;
nuclear@26 422 while (currow < numrows) {
nuclear@26 423 rowsperchunk = MIN(rowsperchunk, numrows - currow);
nuclear@26 424 workspace = (JSAMPROW) alloc_large(cinfo, pool_id,
nuclear@26 425 (size_t) ((size_t) rowsperchunk * (size_t) samplesperrow
nuclear@26 426 * SIZEOF(JSAMPLE)));
nuclear@26 427 for (i = rowsperchunk; i > 0; i--) {
nuclear@26 428 result[currow++] = workspace;
nuclear@26 429 workspace += samplesperrow;
nuclear@26 430 }
nuclear@26 431 }
nuclear@26 432
nuclear@26 433 return result;
nuclear@26 434 }
nuclear@26 435
nuclear@26 436
nuclear@26 437 /*
nuclear@26 438 * Creation of 2-D coefficient-block arrays.
nuclear@26 439 * This is essentially the same as the code for sample arrays, above.
nuclear@26 440 */
nuclear@26 441
nuclear@26 442 METHODDEF(JBLOCKARRAY)
nuclear@26 443 alloc_barray (j_common_ptr cinfo, int pool_id,
nuclear@26 444 JDIMENSION blocksperrow, JDIMENSION numrows)
nuclear@26 445 /* Allocate a 2-D coefficient-block array */
nuclear@26 446 {
nuclear@26 447 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 448 JBLOCKARRAY result;
nuclear@26 449 JBLOCKROW workspace;
nuclear@26 450 JDIMENSION rowsperchunk, currow, i;
nuclear@26 451 long ltemp;
nuclear@26 452
nuclear@26 453 /* Calculate max # of rows allowed in one allocation chunk */
nuclear@26 454 ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
nuclear@26 455 ((long) blocksperrow * SIZEOF(JBLOCK));
nuclear@26 456 if (ltemp <= 0)
nuclear@26 457 ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
nuclear@26 458 if (ltemp < (long) numrows)
nuclear@26 459 rowsperchunk = (JDIMENSION) ltemp;
nuclear@26 460 else
nuclear@26 461 rowsperchunk = numrows;
nuclear@26 462 mem->last_rowsperchunk = rowsperchunk;
nuclear@26 463
nuclear@26 464 /* Get space for row pointers (small object) */
nuclear@26 465 result = (JBLOCKARRAY) alloc_small(cinfo, pool_id,
nuclear@26 466 (size_t) (numrows * SIZEOF(JBLOCKROW)));
nuclear@26 467
nuclear@26 468 /* Get the rows themselves (large objects) */
nuclear@26 469 currow = 0;
nuclear@26 470 while (currow < numrows) {
nuclear@26 471 rowsperchunk = MIN(rowsperchunk, numrows - currow);
nuclear@26 472 workspace = (JBLOCKROW) alloc_large(cinfo, pool_id,
nuclear@26 473 (size_t) ((size_t) rowsperchunk * (size_t) blocksperrow
nuclear@26 474 * SIZEOF(JBLOCK)));
nuclear@26 475 for (i = rowsperchunk; i > 0; i--) {
nuclear@26 476 result[currow++] = workspace;
nuclear@26 477 workspace += blocksperrow;
nuclear@26 478 }
nuclear@26 479 }
nuclear@26 480
nuclear@26 481 return result;
nuclear@26 482 }
nuclear@26 483
nuclear@26 484
nuclear@26 485 /*
nuclear@26 486 * About virtual array management:
nuclear@26 487 *
nuclear@26 488 * The above "normal" array routines are only used to allocate strip buffers
nuclear@26 489 * (as wide as the image, but just a few rows high). Full-image-sized buffers
nuclear@26 490 * are handled as "virtual" arrays. The array is still accessed a strip at a
nuclear@26 491 * time, but the memory manager must save the whole array for repeated
nuclear@26 492 * accesses. The intended implementation is that there is a strip buffer in
nuclear@26 493 * memory (as high as is possible given the desired memory limit), plus a
nuclear@26 494 * backing file that holds the rest of the array.
nuclear@26 495 *
nuclear@26 496 * The request_virt_array routines are told the total size of the image and
nuclear@26 497 * the maximum number of rows that will be accessed at once. The in-memory
nuclear@26 498 * buffer must be at least as large as the maxaccess value.
nuclear@26 499 *
nuclear@26 500 * The request routines create control blocks but not the in-memory buffers.
nuclear@26 501 * That is postponed until realize_virt_arrays is called. At that time the
nuclear@26 502 * total amount of space needed is known (approximately, anyway), so free
nuclear@26 503 * memory can be divided up fairly.
nuclear@26 504 *
nuclear@26 505 * The access_virt_array routines are responsible for making a specific strip
nuclear@26 506 * area accessible (after reading or writing the backing file, if necessary).
nuclear@26 507 * Note that the access routines are told whether the caller intends to modify
nuclear@26 508 * the accessed strip; during a read-only pass this saves having to rewrite
nuclear@26 509 * data to disk. The access routines are also responsible for pre-zeroing
nuclear@26 510 * any newly accessed rows, if pre-zeroing was requested.
nuclear@26 511 *
nuclear@26 512 * In current usage, the access requests are usually for nonoverlapping
nuclear@26 513 * strips; that is, successive access start_row numbers differ by exactly
nuclear@26 514 * num_rows = maxaccess. This means we can get good performance with simple
nuclear@26 515 * buffer dump/reload logic, by making the in-memory buffer be a multiple
nuclear@26 516 * of the access height; then there will never be accesses across bufferload
nuclear@26 517 * boundaries. The code will still work with overlapping access requests,
nuclear@26 518 * but it doesn't handle bufferload overlaps very efficiently.
nuclear@26 519 */
nuclear@26 520
nuclear@26 521
nuclear@26 522 METHODDEF(jvirt_sarray_ptr)
nuclear@26 523 request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
nuclear@26 524 JDIMENSION samplesperrow, JDIMENSION numrows,
nuclear@26 525 JDIMENSION maxaccess)
nuclear@26 526 /* Request a virtual 2-D sample array */
nuclear@26 527 {
nuclear@26 528 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 529 jvirt_sarray_ptr result;
nuclear@26 530
nuclear@26 531 /* Only IMAGE-lifetime virtual arrays are currently supported */
nuclear@26 532 if (pool_id != JPOOL_IMAGE)
nuclear@26 533 ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
nuclear@26 534
nuclear@26 535 /* get control block */
nuclear@26 536 result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id,
nuclear@26 537 SIZEOF(struct jvirt_sarray_control));
nuclear@26 538
nuclear@26 539 result->mem_buffer = NULL; /* marks array not yet realized */
nuclear@26 540 result->rows_in_array = numrows;
nuclear@26 541 result->samplesperrow = samplesperrow;
nuclear@26 542 result->maxaccess = maxaccess;
nuclear@26 543 result->pre_zero = pre_zero;
nuclear@26 544 result->b_s_open = FALSE; /* no associated backing-store object */
nuclear@26 545 result->next = mem->virt_sarray_list; /* add to list of virtual arrays */
nuclear@26 546 mem->virt_sarray_list = result;
nuclear@26 547
nuclear@26 548 return result;
nuclear@26 549 }
nuclear@26 550
nuclear@26 551
nuclear@26 552 METHODDEF(jvirt_barray_ptr)
nuclear@26 553 request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
nuclear@26 554 JDIMENSION blocksperrow, JDIMENSION numrows,
nuclear@26 555 JDIMENSION maxaccess)
nuclear@26 556 /* Request a virtual 2-D coefficient-block array */
nuclear@26 557 {
nuclear@26 558 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 559 jvirt_barray_ptr result;
nuclear@26 560
nuclear@26 561 /* Only IMAGE-lifetime virtual arrays are currently supported */
nuclear@26 562 if (pool_id != JPOOL_IMAGE)
nuclear@26 563 ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
nuclear@26 564
nuclear@26 565 /* get control block */
nuclear@26 566 result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id,
nuclear@26 567 SIZEOF(struct jvirt_barray_control));
nuclear@26 568
nuclear@26 569 result->mem_buffer = NULL; /* marks array not yet realized */
nuclear@26 570 result->rows_in_array = numrows;
nuclear@26 571 result->blocksperrow = blocksperrow;
nuclear@26 572 result->maxaccess = maxaccess;
nuclear@26 573 result->pre_zero = pre_zero;
nuclear@26 574 result->b_s_open = FALSE; /* no associated backing-store object */
nuclear@26 575 result->next = mem->virt_barray_list; /* add to list of virtual arrays */
nuclear@26 576 mem->virt_barray_list = result;
nuclear@26 577
nuclear@26 578 return result;
nuclear@26 579 }
nuclear@26 580
nuclear@26 581
nuclear@26 582 METHODDEF(void)
nuclear@26 583 realize_virt_arrays (j_common_ptr cinfo)
nuclear@26 584 /* Allocate the in-memory buffers for any unrealized virtual arrays */
nuclear@26 585 {
nuclear@26 586 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 587 long space_per_minheight, maximum_space, avail_mem;
nuclear@26 588 long minheights, max_minheights;
nuclear@26 589 jvirt_sarray_ptr sptr;
nuclear@26 590 jvirt_barray_ptr bptr;
nuclear@26 591
nuclear@26 592 /* Compute the minimum space needed (maxaccess rows in each buffer)
nuclear@26 593 * and the maximum space needed (full image height in each buffer).
nuclear@26 594 * These may be of use to the system-dependent jpeg_mem_available routine.
nuclear@26 595 */
nuclear@26 596 space_per_minheight = 0;
nuclear@26 597 maximum_space = 0;
nuclear@26 598 for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
nuclear@26 599 if (sptr->mem_buffer == NULL) { /* if not realized yet */
nuclear@26 600 space_per_minheight += (long) sptr->maxaccess *
nuclear@26 601 (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
nuclear@26 602 maximum_space += (long) sptr->rows_in_array *
nuclear@26 603 (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
nuclear@26 604 }
nuclear@26 605 }
nuclear@26 606 for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
nuclear@26 607 if (bptr->mem_buffer == NULL) { /* if not realized yet */
nuclear@26 608 space_per_minheight += (long) bptr->maxaccess *
nuclear@26 609 (long) bptr->blocksperrow * SIZEOF(JBLOCK);
nuclear@26 610 maximum_space += (long) bptr->rows_in_array *
nuclear@26 611 (long) bptr->blocksperrow * SIZEOF(JBLOCK);
nuclear@26 612 }
nuclear@26 613 }
nuclear@26 614
nuclear@26 615 if (space_per_minheight <= 0)
nuclear@26 616 return; /* no unrealized arrays, no work */
nuclear@26 617
nuclear@26 618 /* Determine amount of memory to actually use; this is system-dependent. */
nuclear@26 619 avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space,
nuclear@26 620 mem->total_space_allocated);
nuclear@26 621
nuclear@26 622 /* If the maximum space needed is available, make all the buffers full
nuclear@26 623 * height; otherwise parcel it out with the same number of minheights
nuclear@26 624 * in each buffer.
nuclear@26 625 */
nuclear@26 626 if (avail_mem >= maximum_space)
nuclear@26 627 max_minheights = 1000000000L;
nuclear@26 628 else {
nuclear@26 629 max_minheights = avail_mem / space_per_minheight;
nuclear@26 630 /* If there doesn't seem to be enough space, try to get the minimum
nuclear@26 631 * anyway. This allows a "stub" implementation of jpeg_mem_available().
nuclear@26 632 */
nuclear@26 633 if (max_minheights <= 0)
nuclear@26 634 max_minheights = 1;
nuclear@26 635 }
nuclear@26 636
nuclear@26 637 /* Allocate the in-memory buffers and initialize backing store as needed. */
nuclear@26 638
nuclear@26 639 for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
nuclear@26 640 if (sptr->mem_buffer == NULL) { /* if not realized yet */
nuclear@26 641 minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L;
nuclear@26 642 if (minheights <= max_minheights) {
nuclear@26 643 /* This buffer fits in memory */
nuclear@26 644 sptr->rows_in_mem = sptr->rows_in_array;
nuclear@26 645 } else {
nuclear@26 646 /* It doesn't fit in memory, create backing store. */
nuclear@26 647 sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess);
nuclear@26 648 jpeg_open_backing_store(cinfo, & sptr->b_s_info,
nuclear@26 649 (long) sptr->rows_in_array *
nuclear@26 650 (long) sptr->samplesperrow *
nuclear@26 651 (long) SIZEOF(JSAMPLE));
nuclear@26 652 sptr->b_s_open = TRUE;
nuclear@26 653 }
nuclear@26 654 sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE,
nuclear@26 655 sptr->samplesperrow, sptr->rows_in_mem);
nuclear@26 656 sptr->rowsperchunk = mem->last_rowsperchunk;
nuclear@26 657 sptr->cur_start_row = 0;
nuclear@26 658 sptr->first_undef_row = 0;
nuclear@26 659 sptr->dirty = FALSE;
nuclear@26 660 }
nuclear@26 661 }
nuclear@26 662
nuclear@26 663 for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
nuclear@26 664 if (bptr->mem_buffer == NULL) { /* if not realized yet */
nuclear@26 665 minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L;
nuclear@26 666 if (minheights <= max_minheights) {
nuclear@26 667 /* This buffer fits in memory */
nuclear@26 668 bptr->rows_in_mem = bptr->rows_in_array;
nuclear@26 669 } else {
nuclear@26 670 /* It doesn't fit in memory, create backing store. */
nuclear@26 671 bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess);
nuclear@26 672 jpeg_open_backing_store(cinfo, & bptr->b_s_info,
nuclear@26 673 (long) bptr->rows_in_array *
nuclear@26 674 (long) bptr->blocksperrow *
nuclear@26 675 (long) SIZEOF(JBLOCK));
nuclear@26 676 bptr->b_s_open = TRUE;
nuclear@26 677 }
nuclear@26 678 bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE,
nuclear@26 679 bptr->blocksperrow, bptr->rows_in_mem);
nuclear@26 680 bptr->rowsperchunk = mem->last_rowsperchunk;
nuclear@26 681 bptr->cur_start_row = 0;
nuclear@26 682 bptr->first_undef_row = 0;
nuclear@26 683 bptr->dirty = FALSE;
nuclear@26 684 }
nuclear@26 685 }
nuclear@26 686 }
nuclear@26 687
nuclear@26 688
nuclear@26 689 LOCAL(void)
nuclear@26 690 do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing)
nuclear@26 691 /* Do backing store read or write of a virtual sample array */
nuclear@26 692 {
nuclear@26 693 long bytesperrow, file_offset, byte_count, rows, thisrow, i;
nuclear@26 694
nuclear@26 695 bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE);
nuclear@26 696 file_offset = ptr->cur_start_row * bytesperrow;
nuclear@26 697 /* Loop to read or write each allocation chunk in mem_buffer */
nuclear@26 698 for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
nuclear@26 699 /* One chunk, but check for short chunk at end of buffer */
nuclear@26 700 rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
nuclear@26 701 /* Transfer no more than is currently defined */
nuclear@26 702 thisrow = (long) ptr->cur_start_row + i;
nuclear@26 703 rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
nuclear@26 704 /* Transfer no more than fits in file */
nuclear@26 705 rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
nuclear@26 706 if (rows <= 0) /* this chunk might be past end of file! */
nuclear@26 707 break;
nuclear@26 708 byte_count = rows * bytesperrow;
nuclear@26 709 if (writing)
nuclear@26 710 (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
nuclear@26 711 (void FAR *) ptr->mem_buffer[i],
nuclear@26 712 file_offset, byte_count);
nuclear@26 713 else
nuclear@26 714 (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
nuclear@26 715 (void FAR *) ptr->mem_buffer[i],
nuclear@26 716 file_offset, byte_count);
nuclear@26 717 file_offset += byte_count;
nuclear@26 718 }
nuclear@26 719 }
nuclear@26 720
nuclear@26 721
nuclear@26 722 LOCAL(void)
nuclear@26 723 do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing)
nuclear@26 724 /* Do backing store read or write of a virtual coefficient-block array */
nuclear@26 725 {
nuclear@26 726 long bytesperrow, file_offset, byte_count, rows, thisrow, i;
nuclear@26 727
nuclear@26 728 bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK);
nuclear@26 729 file_offset = ptr->cur_start_row * bytesperrow;
nuclear@26 730 /* Loop to read or write each allocation chunk in mem_buffer */
nuclear@26 731 for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
nuclear@26 732 /* One chunk, but check for short chunk at end of buffer */
nuclear@26 733 rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
nuclear@26 734 /* Transfer no more than is currently defined */
nuclear@26 735 thisrow = (long) ptr->cur_start_row + i;
nuclear@26 736 rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
nuclear@26 737 /* Transfer no more than fits in file */
nuclear@26 738 rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
nuclear@26 739 if (rows <= 0) /* this chunk might be past end of file! */
nuclear@26 740 break;
nuclear@26 741 byte_count = rows * bytesperrow;
nuclear@26 742 if (writing)
nuclear@26 743 (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
nuclear@26 744 (void FAR *) ptr->mem_buffer[i],
nuclear@26 745 file_offset, byte_count);
nuclear@26 746 else
nuclear@26 747 (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
nuclear@26 748 (void FAR *) ptr->mem_buffer[i],
nuclear@26 749 file_offset, byte_count);
nuclear@26 750 file_offset += byte_count;
nuclear@26 751 }
nuclear@26 752 }
nuclear@26 753
nuclear@26 754
nuclear@26 755 METHODDEF(JSAMPARRAY)
nuclear@26 756 access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
nuclear@26 757 JDIMENSION start_row, JDIMENSION num_rows,
nuclear@26 758 boolean writable)
nuclear@26 759 /* Access the part of a virtual sample array starting at start_row */
nuclear@26 760 /* and extending for num_rows rows. writable is true if */
nuclear@26 761 /* caller intends to modify the accessed area. */
nuclear@26 762 {
nuclear@26 763 JDIMENSION end_row = start_row + num_rows;
nuclear@26 764 JDIMENSION undef_row;
nuclear@26 765
nuclear@26 766 /* debugging check */
nuclear@26 767 if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
nuclear@26 768 ptr->mem_buffer == NULL)
nuclear@26 769 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 770
nuclear@26 771 /* Make the desired part of the virtual array accessible */
nuclear@26 772 if (start_row < ptr->cur_start_row ||
nuclear@26 773 end_row > ptr->cur_start_row+ptr->rows_in_mem) {
nuclear@26 774 if (! ptr->b_s_open)
nuclear@26 775 ERREXIT(cinfo, JERR_VIRTUAL_BUG);
nuclear@26 776 /* Flush old buffer contents if necessary */
nuclear@26 777 if (ptr->dirty) {
nuclear@26 778 do_sarray_io(cinfo, ptr, TRUE);
nuclear@26 779 ptr->dirty = FALSE;
nuclear@26 780 }
nuclear@26 781 /* Decide what part of virtual array to access.
nuclear@26 782 * Algorithm: if target address > current window, assume forward scan,
nuclear@26 783 * load starting at target address. If target address < current window,
nuclear@26 784 * assume backward scan, load so that target area is top of window.
nuclear@26 785 * Note that when switching from forward write to forward read, will have
nuclear@26 786 * start_row = 0, so the limiting case applies and we load from 0 anyway.
nuclear@26 787 */
nuclear@26 788 if (start_row > ptr->cur_start_row) {
nuclear@26 789 ptr->cur_start_row = start_row;
nuclear@26 790 } else {
nuclear@26 791 /* use long arithmetic here to avoid overflow & unsigned problems */
nuclear@26 792 long ltemp;
nuclear@26 793
nuclear@26 794 ltemp = (long) end_row - (long) ptr->rows_in_mem;
nuclear@26 795 if (ltemp < 0)
nuclear@26 796 ltemp = 0; /* don't fall off front end of file */
nuclear@26 797 ptr->cur_start_row = (JDIMENSION) ltemp;
nuclear@26 798 }
nuclear@26 799 /* Read in the selected part of the array.
nuclear@26 800 * During the initial write pass, we will do no actual read
nuclear@26 801 * because the selected part is all undefined.
nuclear@26 802 */
nuclear@26 803 do_sarray_io(cinfo, ptr, FALSE);
nuclear@26 804 }
nuclear@26 805 /* Ensure the accessed part of the array is defined; prezero if needed.
nuclear@26 806 * To improve locality of access, we only prezero the part of the array
nuclear@26 807 * that the caller is about to access, not the entire in-memory array.
nuclear@26 808 */
nuclear@26 809 if (ptr->first_undef_row < end_row) {
nuclear@26 810 if (ptr->first_undef_row < start_row) {
nuclear@26 811 if (writable) /* writer skipped over a section of array */
nuclear@26 812 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 813 undef_row = start_row; /* but reader is allowed to read ahead */
nuclear@26 814 } else {
nuclear@26 815 undef_row = ptr->first_undef_row;
nuclear@26 816 }
nuclear@26 817 if (writable)
nuclear@26 818 ptr->first_undef_row = end_row;
nuclear@26 819 if (ptr->pre_zero) {
nuclear@26 820 size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE);
nuclear@26 821 undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
nuclear@26 822 end_row -= ptr->cur_start_row;
nuclear@26 823 while (undef_row < end_row) {
nuclear@26 824 jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
nuclear@26 825 undef_row++;
nuclear@26 826 }
nuclear@26 827 } else {
nuclear@26 828 if (! writable) /* reader looking at undefined data */
nuclear@26 829 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 830 }
nuclear@26 831 }
nuclear@26 832 /* Flag the buffer dirty if caller will write in it */
nuclear@26 833 if (writable)
nuclear@26 834 ptr->dirty = TRUE;
nuclear@26 835 /* Return address of proper part of the buffer */
nuclear@26 836 return ptr->mem_buffer + (start_row - ptr->cur_start_row);
nuclear@26 837 }
nuclear@26 838
nuclear@26 839
nuclear@26 840 METHODDEF(JBLOCKARRAY)
nuclear@26 841 access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr,
nuclear@26 842 JDIMENSION start_row, JDIMENSION num_rows,
nuclear@26 843 boolean writable)
nuclear@26 844 /* Access the part of a virtual block array starting at start_row */
nuclear@26 845 /* and extending for num_rows rows. writable is true if */
nuclear@26 846 /* caller intends to modify the accessed area. */
nuclear@26 847 {
nuclear@26 848 JDIMENSION end_row = start_row + num_rows;
nuclear@26 849 JDIMENSION undef_row;
nuclear@26 850
nuclear@26 851 /* debugging check */
nuclear@26 852 if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
nuclear@26 853 ptr->mem_buffer == NULL)
nuclear@26 854 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 855
nuclear@26 856 /* Make the desired part of the virtual array accessible */
nuclear@26 857 if (start_row < ptr->cur_start_row ||
nuclear@26 858 end_row > ptr->cur_start_row+ptr->rows_in_mem) {
nuclear@26 859 if (! ptr->b_s_open)
nuclear@26 860 ERREXIT(cinfo, JERR_VIRTUAL_BUG);
nuclear@26 861 /* Flush old buffer contents if necessary */
nuclear@26 862 if (ptr->dirty) {
nuclear@26 863 do_barray_io(cinfo, ptr, TRUE);
nuclear@26 864 ptr->dirty = FALSE;
nuclear@26 865 }
nuclear@26 866 /* Decide what part of virtual array to access.
nuclear@26 867 * Algorithm: if target address > current window, assume forward scan,
nuclear@26 868 * load starting at target address. If target address < current window,
nuclear@26 869 * assume backward scan, load so that target area is top of window.
nuclear@26 870 * Note that when switching from forward write to forward read, will have
nuclear@26 871 * start_row = 0, so the limiting case applies and we load from 0 anyway.
nuclear@26 872 */
nuclear@26 873 if (start_row > ptr->cur_start_row) {
nuclear@26 874 ptr->cur_start_row = start_row;
nuclear@26 875 } else {
nuclear@26 876 /* use long arithmetic here to avoid overflow & unsigned problems */
nuclear@26 877 long ltemp;
nuclear@26 878
nuclear@26 879 ltemp = (long) end_row - (long) ptr->rows_in_mem;
nuclear@26 880 if (ltemp < 0)
nuclear@26 881 ltemp = 0; /* don't fall off front end of file */
nuclear@26 882 ptr->cur_start_row = (JDIMENSION) ltemp;
nuclear@26 883 }
nuclear@26 884 /* Read in the selected part of the array.
nuclear@26 885 * During the initial write pass, we will do no actual read
nuclear@26 886 * because the selected part is all undefined.
nuclear@26 887 */
nuclear@26 888 do_barray_io(cinfo, ptr, FALSE);
nuclear@26 889 }
nuclear@26 890 /* Ensure the accessed part of the array is defined; prezero if needed.
nuclear@26 891 * To improve locality of access, we only prezero the part of the array
nuclear@26 892 * that the caller is about to access, not the entire in-memory array.
nuclear@26 893 */
nuclear@26 894 if (ptr->first_undef_row < end_row) {
nuclear@26 895 if (ptr->first_undef_row < start_row) {
nuclear@26 896 if (writable) /* writer skipped over a section of array */
nuclear@26 897 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 898 undef_row = start_row; /* but reader is allowed to read ahead */
nuclear@26 899 } else {
nuclear@26 900 undef_row = ptr->first_undef_row;
nuclear@26 901 }
nuclear@26 902 if (writable)
nuclear@26 903 ptr->first_undef_row = end_row;
nuclear@26 904 if (ptr->pre_zero) {
nuclear@26 905 size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK);
nuclear@26 906 undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
nuclear@26 907 end_row -= ptr->cur_start_row;
nuclear@26 908 while (undef_row < end_row) {
nuclear@26 909 jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
nuclear@26 910 undef_row++;
nuclear@26 911 }
nuclear@26 912 } else {
nuclear@26 913 if (! writable) /* reader looking at undefined data */
nuclear@26 914 ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
nuclear@26 915 }
nuclear@26 916 }
nuclear@26 917 /* Flag the buffer dirty if caller will write in it */
nuclear@26 918 if (writable)
nuclear@26 919 ptr->dirty = TRUE;
nuclear@26 920 /* Return address of proper part of the buffer */
nuclear@26 921 return ptr->mem_buffer + (start_row - ptr->cur_start_row);
nuclear@26 922 }
nuclear@26 923
nuclear@26 924
nuclear@26 925 /*
nuclear@26 926 * Release all objects belonging to a specified pool.
nuclear@26 927 */
nuclear@26 928
nuclear@26 929 METHODDEF(void)
nuclear@26 930 free_pool (j_common_ptr cinfo, int pool_id)
nuclear@26 931 {
nuclear@26 932 my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
nuclear@26 933 small_pool_ptr shdr_ptr;
nuclear@26 934 large_pool_ptr lhdr_ptr;
nuclear@26 935 size_t space_freed;
nuclear@26 936
nuclear@26 937 if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
nuclear@26 938 ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
nuclear@26 939
nuclear@26 940 #ifdef MEM_STATS
nuclear@26 941 if (cinfo->err->trace_level > 1)
nuclear@26 942 print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */
nuclear@26 943 #endif
nuclear@26 944
nuclear@26 945 /* If freeing IMAGE pool, close any virtual arrays first */
nuclear@26 946 if (pool_id == JPOOL_IMAGE) {
nuclear@26 947 jvirt_sarray_ptr sptr;
nuclear@26 948 jvirt_barray_ptr bptr;
nuclear@26 949
nuclear@26 950 for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
nuclear@26 951 if (sptr->b_s_open) { /* there may be no backing store */
nuclear@26 952 sptr->b_s_open = FALSE; /* prevent recursive close if error */
nuclear@26 953 (*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info);
nuclear@26 954 }
nuclear@26 955 }
nuclear@26 956 mem->virt_sarray_list = NULL;
nuclear@26 957 for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
nuclear@26 958 if (bptr->b_s_open) { /* there may be no backing store */
nuclear@26 959 bptr->b_s_open = FALSE; /* prevent recursive close if error */
nuclear@26 960 (*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info);
nuclear@26 961 }
nuclear@26 962 }
nuclear@26 963 mem->virt_barray_list = NULL;
nuclear@26 964 }
nuclear@26 965
nuclear@26 966 /* Release large objects */
nuclear@26 967 lhdr_ptr = mem->large_list[pool_id];
nuclear@26 968 mem->large_list[pool_id] = NULL;
nuclear@26 969
nuclear@26 970 while (lhdr_ptr != NULL) {
nuclear@26 971 large_pool_ptr next_lhdr_ptr = lhdr_ptr->hdr.next;
nuclear@26 972 space_freed = lhdr_ptr->hdr.bytes_used +
nuclear@26 973 lhdr_ptr->hdr.bytes_left +
nuclear@26 974 SIZEOF(large_pool_hdr);
nuclear@26 975 jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed);
nuclear@26 976 mem->total_space_allocated -= space_freed;
nuclear@26 977 lhdr_ptr = next_lhdr_ptr;
nuclear@26 978 }
nuclear@26 979
nuclear@26 980 /* Release small objects */
nuclear@26 981 shdr_ptr = mem->small_list[pool_id];
nuclear@26 982 mem->small_list[pool_id] = NULL;
nuclear@26 983
nuclear@26 984 while (shdr_ptr != NULL) {
nuclear@26 985 small_pool_ptr next_shdr_ptr = shdr_ptr->hdr.next;
nuclear@26 986 space_freed = shdr_ptr->hdr.bytes_used +
nuclear@26 987 shdr_ptr->hdr.bytes_left +
nuclear@26 988 SIZEOF(small_pool_hdr);
nuclear@26 989 jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed);
nuclear@26 990 mem->total_space_allocated -= space_freed;
nuclear@26 991 shdr_ptr = next_shdr_ptr;
nuclear@26 992 }
nuclear@26 993 }
nuclear@26 994
nuclear@26 995
nuclear@26 996 /*
nuclear@26 997 * Close up shop entirely.
nuclear@26 998 * Note that this cannot be called unless cinfo->mem is non-NULL.
nuclear@26 999 */
nuclear@26 1000
nuclear@26 1001 METHODDEF(void)
nuclear@26 1002 self_destruct (j_common_ptr cinfo)
nuclear@26 1003 {
nuclear@26 1004 int pool;
nuclear@26 1005
nuclear@26 1006 /* Close all backing store, release all memory.
nuclear@26 1007 * Releasing pools in reverse order might help avoid fragmentation
nuclear@26 1008 * with some (brain-damaged) malloc libraries.
nuclear@26 1009 */
nuclear@26 1010 for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
nuclear@26 1011 free_pool(cinfo, pool);
nuclear@26 1012 }
nuclear@26 1013
nuclear@26 1014 /* Release the memory manager control block too. */
nuclear@26 1015 jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr));
nuclear@26 1016 cinfo->mem = NULL; /* ensures I will be called only once */
nuclear@26 1017
nuclear@26 1018 jpeg_mem_term(cinfo); /* system-dependent cleanup */
nuclear@26 1019 }
nuclear@26 1020
nuclear@26 1021
nuclear@26 1022 /*
nuclear@26 1023 * Memory manager initialization.
nuclear@26 1024 * When this is called, only the error manager pointer is valid in cinfo!
nuclear@26 1025 */
nuclear@26 1026
nuclear@26 1027 GLOBAL(void)
nuclear@26 1028 jinit_memory_mgr (j_common_ptr cinfo)
nuclear@26 1029 {
nuclear@26 1030 my_mem_ptr mem;
nuclear@26 1031 long max_to_use;
nuclear@26 1032 int pool;
nuclear@26 1033 size_t test_mac;
nuclear@26 1034
nuclear@26 1035 cinfo->mem = NULL; /* for safety if init fails */
nuclear@26 1036
nuclear@26 1037 /* Check for configuration errors.
nuclear@26 1038 * SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably
nuclear@26 1039 * doesn't reflect any real hardware alignment requirement.
nuclear@26 1040 * The test is a little tricky: for X>0, X and X-1 have no one-bits
nuclear@26 1041 * in common if and only if X is a power of 2, ie has only one one-bit.
nuclear@26 1042 * Some compilers may give an "unreachable code" warning here; ignore it.
nuclear@26 1043 */
nuclear@26 1044 if ((SIZEOF(ALIGN_TYPE) & (SIZEOF(ALIGN_TYPE)-1)) != 0)
nuclear@26 1045 ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE);
nuclear@26 1046 /* MAX_ALLOC_CHUNK must be representable as type size_t, and must be
nuclear@26 1047 * a multiple of SIZEOF(ALIGN_TYPE).
nuclear@26 1048 * Again, an "unreachable code" warning may be ignored here.
nuclear@26 1049 * But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK.
nuclear@26 1050 */
nuclear@26 1051 test_mac = (size_t) MAX_ALLOC_CHUNK;
nuclear@26 1052 if ((long) test_mac != MAX_ALLOC_CHUNK ||
nuclear@26 1053 (MAX_ALLOC_CHUNK % SIZEOF(ALIGN_TYPE)) != 0)
nuclear@26 1054 ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
nuclear@26 1055
nuclear@26 1056 max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */
nuclear@26 1057
nuclear@26 1058 /* Attempt to allocate memory manager's control block */
nuclear@26 1059 mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr));
nuclear@26 1060
nuclear@26 1061 if (mem == NULL) {
nuclear@26 1062 jpeg_mem_term(cinfo); /* system-dependent cleanup */
nuclear@26 1063 ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0);
nuclear@26 1064 }
nuclear@26 1065
nuclear@26 1066 /* OK, fill in the method pointers */
nuclear@26 1067 mem->pub.alloc_small = alloc_small;
nuclear@26 1068 mem->pub.alloc_large = alloc_large;
nuclear@26 1069 mem->pub.alloc_sarray = alloc_sarray;
nuclear@26 1070 mem->pub.alloc_barray = alloc_barray;
nuclear@26 1071 mem->pub.request_virt_sarray = request_virt_sarray;
nuclear@26 1072 mem->pub.request_virt_barray = request_virt_barray;
nuclear@26 1073 mem->pub.realize_virt_arrays = realize_virt_arrays;
nuclear@26 1074 mem->pub.access_virt_sarray = access_virt_sarray;
nuclear@26 1075 mem->pub.access_virt_barray = access_virt_barray;
nuclear@26 1076 mem->pub.free_pool = free_pool;
nuclear@26 1077 mem->pub.self_destruct = self_destruct;
nuclear@26 1078
nuclear@26 1079 /* Make MAX_ALLOC_CHUNK accessible to other modules */
nuclear@26 1080 mem->pub.max_alloc_chunk = MAX_ALLOC_CHUNK;
nuclear@26 1081
nuclear@26 1082 /* Initialize working state */
nuclear@26 1083 mem->pub.max_memory_to_use = max_to_use;
nuclear@26 1084
nuclear@26 1085 for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
nuclear@26 1086 mem->small_list[pool] = NULL;
nuclear@26 1087 mem->large_list[pool] = NULL;
nuclear@26 1088 }
nuclear@26 1089 mem->virt_sarray_list = NULL;
nuclear@26 1090 mem->virt_barray_list = NULL;
nuclear@26 1091
nuclear@26 1092 mem->total_space_allocated = SIZEOF(my_memory_mgr);
nuclear@26 1093
nuclear@26 1094 /* Declare ourselves open for business */
nuclear@26 1095 cinfo->mem = & mem->pub;
nuclear@26 1096
nuclear@26 1097 /* Check for an environment variable JPEGMEM; if found, override the
nuclear@26 1098 * default max_memory setting from jpeg_mem_init. Note that the
nuclear@26 1099 * surrounding application may again override this value.
nuclear@26 1100 * If your system doesn't support getenv(), define NO_GETENV to disable
nuclear@26 1101 * this feature.
nuclear@26 1102 */
nuclear@26 1103 #ifndef NO_GETENV
nuclear@26 1104 { char * memenv;
nuclear@26 1105
nuclear@26 1106 if ((memenv = getenv("JPEGMEM")) != NULL) {
nuclear@26 1107 char ch = 'x';
nuclear@26 1108
nuclear@26 1109 if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) {
nuclear@26 1110 if (ch == 'm' || ch == 'M')
nuclear@26 1111 max_to_use *= 1000L;
nuclear@26 1112 mem->pub.max_memory_to_use = max_to_use * 1000L;
nuclear@26 1113 }
nuclear@26 1114 }
nuclear@26 1115 }
nuclear@26 1116 #endif
nuclear@26 1117
nuclear@26 1118 }