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Diffstat (limited to 'code/jpeg-6/jmemmgr.c')
| -rwxr-xr-x | code/jpeg-6/jmemmgr.c | 1115 |
1 files changed, 1115 insertions, 0 deletions
diff --git a/code/jpeg-6/jmemmgr.c b/code/jpeg-6/jmemmgr.c new file mode 100755 index 0000000..61045f9 --- /dev/null +++ b/code/jpeg-6/jmemmgr.c @@ -0,0 +1,1115 @@ +/*
+ * jmemmgr.c
+ *
+ * Copyright (C) 1991-1995, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains the JPEG system-independent memory management
+ * routines. This code is usable across a wide variety of machines; most
+ * of the system dependencies have been isolated in a separate file.
+ * The major functions provided here are:
+ * * pool-based allocation and freeing of memory;
+ * * policy decisions about how to divide available memory among the
+ * virtual arrays;
+ * * control logic for swapping virtual arrays between main memory and
+ * backing storage.
+ * The separate system-dependent file provides the actual backing-storage
+ * access code, and it contains the policy decision about how much total
+ * main memory to use.
+ * This file is system-dependent in the sense that some of its functions
+ * are unnecessary in some systems. For example, if there is enough virtual
+ * memory so that backing storage will never be used, much of the virtual
+ * array control logic could be removed. (Of course, if you have that much
+ * memory then you shouldn't care about a little bit of unused code...)
+ */
+
+#define JPEG_INTERNALS
+#define AM_MEMORY_MANAGER /* we define jvirt_Xarray_control structs */
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jmemsys.h" /* import the system-dependent declarations */
+
+#ifndef NO_GETENV
+#ifndef HAVE_STDLIB_H /* <stdlib.h> should declare getenv() */
+extern char * getenv JPP((const char * name));
+#endif
+#endif
+
+
+/*
+ * Some important notes:
+ * The allocation routines provided here must never return NULL.
+ * They should exit to error_exit if unsuccessful.
+ *
+ * It's not a good idea to try to merge the sarray and barray routines,
+ * even though they are textually almost the same, because samples are
+ * usually stored as bytes while coefficients are shorts or ints. Thus,
+ * in machines where byte pointers have a different representation from
+ * word pointers, the resulting machine code could not be the same.
+ */
+
+
+/*
+ * Many machines require storage alignment: longs must start on 4-byte
+ * boundaries, doubles on 8-byte boundaries, etc. On such machines, malloc()
+ * always returns pointers that are multiples of the worst-case alignment
+ * requirement, and we had better do so too.
+ * There isn't any really portable way to determine the worst-case alignment
+ * requirement. This module assumes that the alignment requirement is
+ * multiples of sizeof(ALIGN_TYPE).
+ * By default, we define ALIGN_TYPE as double. This is necessary on some
+ * workstations (where doubles really do need 8-byte alignment) and will work
+ * fine on nearly everything. If your machine has lesser alignment needs,
+ * you can save a few bytes by making ALIGN_TYPE smaller.
+ * The only place I know of where this will NOT work is certain Macintosh
+ * 680x0 compilers that define double as a 10-byte IEEE extended float.
+ * Doing 10-byte alignment is counterproductive because longwords won't be
+ * aligned well. Put "#define ALIGN_TYPE long" in jconfig.h if you have
+ * such a compiler.
+ */
+
+#ifndef ALIGN_TYPE /* so can override from jconfig.h */
+#define ALIGN_TYPE double
+#endif
+
+
+/*
+ * We allocate objects from "pools", where each pool is gotten with a single
+ * request to jpeg_get_small() or jpeg_get_large(). There is no per-object
+ * overhead within a pool, except for alignment padding. Each pool has a
+ * header with a link to the next pool of the same class.
+ * Small and large pool headers are identical except that the latter's
+ * link pointer must be FAR on 80x86 machines.
+ * Notice that the "real" header fields are union'ed with a dummy ALIGN_TYPE
+ * field. This forces the compiler to make SIZEOF(small_pool_hdr) a multiple
+ * of the alignment requirement of ALIGN_TYPE.
+ */
+
+typedef union small_pool_struct * small_pool_ptr;
+
+typedef union small_pool_struct {
+ struct {
+ small_pool_ptr next; /* next in list of pools */
+ size_t bytes_used; /* how many bytes already used within pool */
+ size_t bytes_left; /* bytes still available in this pool */
+ } hdr;
+ ALIGN_TYPE dummy; /* included in union to ensure alignment */
+} small_pool_hdr;
+
+typedef union large_pool_struct FAR * large_pool_ptr;
+
+typedef union large_pool_struct {
+ struct {
+ large_pool_ptr next; /* next in list of pools */
+ size_t bytes_used; /* how many bytes already used within pool */
+ size_t bytes_left; /* bytes still available in this pool */
+ } hdr;
+ ALIGN_TYPE dummy; /* included in union to ensure alignment */
+} large_pool_hdr;
+
+
+/*
+ * Here is the full definition of a memory manager object.
+ */
+
+typedef struct {
+ struct jpeg_memory_mgr pub; /* public fields */
+
+ /* Each pool identifier (lifetime class) names a linked list of pools. */
+ small_pool_ptr small_list[JPOOL_NUMPOOLS];
+ large_pool_ptr large_list[JPOOL_NUMPOOLS];
+
+ /* Since we only have one lifetime class of virtual arrays, only one
+ * linked list is necessary (for each datatype). Note that the virtual
+ * array control blocks being linked together are actually stored somewhere
+ * in the small-pool list.
+ */
+ jvirt_sarray_ptr virt_sarray_list;
+ jvirt_barray_ptr virt_barray_list;
+
+ /* This counts total space obtained from jpeg_get_small/large */
+ long total_space_allocated;
+
+ /* alloc_sarray and alloc_barray set this value for use by virtual
+ * array routines.
+ */
+ JDIMENSION last_rowsperchunk; /* from most recent alloc_sarray/barray */
+} my_memory_mgr;
+
+typedef my_memory_mgr * my_mem_ptr;
+
+
+/*
+ * The control blocks for virtual arrays.
+ * Note that these blocks are allocated in the "small" pool area.
+ * System-dependent info for the associated backing store (if any) is hidden
+ * inside the backing_store_info struct.
+ */
+
+struct jvirt_sarray_control {
+ JSAMPARRAY mem_buffer; /* => the in-memory buffer */
+ JDIMENSION rows_in_array; /* total virtual array height */
+ JDIMENSION samplesperrow; /* width of array (and of memory buffer) */
+ JDIMENSION maxaccess; /* max rows accessed by access_virt_sarray */
+ JDIMENSION rows_in_mem; /* height of memory buffer */
+ JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
+ JDIMENSION cur_start_row; /* first logical row # in the buffer */
+ JDIMENSION first_undef_row; /* row # of first uninitialized row */
+ boolean pre_zero; /* pre-zero mode requested? */
+ boolean dirty; /* do current buffer contents need written? */
+ boolean b_s_open; /* is backing-store data valid? */
+ jvirt_sarray_ptr next; /* link to next virtual sarray control block */
+ backing_store_info b_s_info; /* System-dependent control info */
+};
+
+struct jvirt_barray_control {
+ JBLOCKARRAY mem_buffer; /* => the in-memory buffer */
+ JDIMENSION rows_in_array; /* total virtual array height */
+ JDIMENSION blocksperrow; /* width of array (and of memory buffer) */
+ JDIMENSION maxaccess; /* max rows accessed by access_virt_barray */
+ JDIMENSION rows_in_mem; /* height of memory buffer */
+ JDIMENSION rowsperchunk; /* allocation chunk size in mem_buffer */
+ JDIMENSION cur_start_row; /* first logical row # in the buffer */
+ JDIMENSION first_undef_row; /* row # of first uninitialized row */
+ boolean pre_zero; /* pre-zero mode requested? */
+ boolean dirty; /* do current buffer contents need written? */
+ boolean b_s_open; /* is backing-store data valid? */
+ jvirt_barray_ptr next; /* link to next virtual barray control block */
+ backing_store_info b_s_info; /* System-dependent control info */
+};
+
+
+#ifdef MEM_STATS /* optional extra stuff for statistics */
+
+LOCAL void
+print_mem_stats (j_common_ptr cinfo, int pool_id)
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ small_pool_ptr shdr_ptr;
+ large_pool_ptr lhdr_ptr;
+
+ /* Since this is only a debugging stub, we can cheat a little by using
+ * fprintf directly rather than going through the trace message code.
+ * This is helpful because message parm array can't handle longs.
+ */
+ fprintf(stderr, "Freeing pool %d, total space = %ld\n",
+ pool_id, mem->total_space_allocated);
+
+ for (lhdr_ptr = mem->large_list[pool_id]; lhdr_ptr != NULL;
+ lhdr_ptr = lhdr_ptr->hdr.next) {
+ fprintf(stderr, " Large chunk used %ld\n",
+ (long) lhdr_ptr->hdr.bytes_used);
+ }
+
+ for (shdr_ptr = mem->small_list[pool_id]; shdr_ptr != NULL;
+ shdr_ptr = shdr_ptr->hdr.next) {
+ fprintf(stderr, " Small chunk used %ld free %ld\n",
+ (long) shdr_ptr->hdr.bytes_used,
+ (long) shdr_ptr->hdr.bytes_left);
+ }
+}
+
+#endif /* MEM_STATS */
+
+
+LOCAL void
+out_of_memory (j_common_ptr cinfo, int which)
+/* Report an out-of-memory error and stop execution */
+/* If we compiled MEM_STATS support, report alloc requests before dying */
+{
+#ifdef MEM_STATS
+ cinfo->err->trace_level = 2; /* force self_destruct to report stats */
+#endif
+ ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, which);
+}
+
+
+/*
+ * Allocation of "small" objects.
+ *
+ * For these, we use pooled storage. When a new pool must be created,
+ * we try to get enough space for the current request plus a "slop" factor,
+ * where the slop will be the amount of leftover space in the new pool.
+ * The speed vs. space tradeoff is largely determined by the slop values.
+ * A different slop value is provided for each pool class (lifetime),
+ * and we also distinguish the first pool of a class from later ones.
+ * NOTE: the values given work fairly well on both 16- and 32-bit-int
+ * machines, but may be too small if longs are 64 bits or more.
+ */
+
+static const size_t first_pool_slop[JPOOL_NUMPOOLS] =
+{
+ 1600, /* first PERMANENT pool */
+ 16000 /* first IMAGE pool */
+};
+
+static const size_t extra_pool_slop[JPOOL_NUMPOOLS] =
+{
+ 0, /* additional PERMANENT pools */
+ 5000 /* additional IMAGE pools */
+};
+
+#define MIN_SLOP 50 /* greater than 0 to avoid futile looping */
+
+
+METHODDEF void *
+alloc_small (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
+/* Allocate a "small" object */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ small_pool_ptr hdr_ptr, prev_hdr_ptr;
+ char * data_ptr;
+ size_t odd_bytes, min_request, slop;
+
+ /* Check for unsatisfiable request (do now to ensure no overflow below) */
+ if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(small_pool_hdr)))
+ out_of_memory(cinfo, 1); /* request exceeds malloc's ability */
+
+ /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
+ odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
+ if (odd_bytes > 0)
+ sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
+
+ /* See if space is available in any existing pool */
+ if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
+ ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
+ prev_hdr_ptr = NULL;
+ hdr_ptr = mem->small_list[pool_id];
+ while (hdr_ptr != NULL) {
+ if (hdr_ptr->hdr.bytes_left >= sizeofobject)
+ break; /* found pool with enough space */
+ prev_hdr_ptr = hdr_ptr;
+ hdr_ptr = hdr_ptr->hdr.next;
+ }
+
+ /* Time to make a new pool? */
+ if (hdr_ptr == NULL) {
+ /* min_request is what we need now, slop is what will be leftover */
+ min_request = sizeofobject + SIZEOF(small_pool_hdr);
+ if (prev_hdr_ptr == NULL) /* first pool in class? */
+ slop = first_pool_slop[pool_id];
+ else
+ slop = extra_pool_slop[pool_id];
+ /* Don't ask for more than MAX_ALLOC_CHUNK */
+ if (slop > (size_t) (MAX_ALLOC_CHUNK-min_request))
+ slop = (size_t) (MAX_ALLOC_CHUNK-min_request);
+ /* Try to get space, if fail reduce slop and try again */
+ for (;;) {
+ hdr_ptr = (small_pool_ptr) jpeg_get_small(cinfo, min_request + slop);
+ if (hdr_ptr != NULL)
+ break;
+ slop /= 2;
+ if (slop < MIN_SLOP) /* give up when it gets real small */
+ out_of_memory(cinfo, 2); /* jpeg_get_small failed */
+ }
+ mem->total_space_allocated += min_request + slop;
+ /* Success, initialize the new pool header and add to end of list */
+ hdr_ptr->hdr.next = NULL;
+ hdr_ptr->hdr.bytes_used = 0;
+ hdr_ptr->hdr.bytes_left = sizeofobject + slop;
+ if (prev_hdr_ptr == NULL) /* first pool in class? */
+ mem->small_list[pool_id] = hdr_ptr;
+ else
+ prev_hdr_ptr->hdr.next = hdr_ptr;
+ }
+
+ /* OK, allocate the object from the current pool */
+ data_ptr = (char *) (hdr_ptr + 1); /* point to first data byte in pool */
+ data_ptr += hdr_ptr->hdr.bytes_used; /* point to place for object */
+ hdr_ptr->hdr.bytes_used += sizeofobject;
+ hdr_ptr->hdr.bytes_left -= sizeofobject;
+
+ return (void *) data_ptr;
+}
+
+
+/*
+ * Allocation of "large" objects.
+ *
+ * The external semantics of these are the same as "small" objects,
+ * except that FAR pointers are used on 80x86. However the pool
+ * management heuristics are quite different. We assume that each
+ * request is large enough that it may as well be passed directly to
+ * jpeg_get_large; the pool management just links everything together
+ * so that we can free it all on demand.
+ * Note: the major use of "large" objects is in JSAMPARRAY and JBLOCKARRAY
+ * structures. The routines that create these structures (see below)
+ * deliberately bunch rows together to ensure a large request size.
+ */
+
+METHODDEF void FAR *
+alloc_large (j_common_ptr cinfo, int pool_id, size_t sizeofobject)
+/* Allocate a "large" object */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ large_pool_ptr hdr_ptr;
+ size_t odd_bytes;
+
+ /* Check for unsatisfiable request (do now to ensure no overflow below) */
+ if (sizeofobject > (size_t) (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)))
+ out_of_memory(cinfo, 3); /* request exceeds malloc's ability */
+
+ /* Round up the requested size to a multiple of SIZEOF(ALIGN_TYPE) */
+ odd_bytes = sizeofobject % SIZEOF(ALIGN_TYPE);
+ if (odd_bytes > 0)
+ sizeofobject += SIZEOF(ALIGN_TYPE) - odd_bytes;
+
+ /* Always make a new pool */
+ if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
+ ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
+
+ hdr_ptr = (large_pool_ptr) jpeg_get_large(cinfo, sizeofobject +
+ SIZEOF(large_pool_hdr));
+ if (hdr_ptr == NULL)
+ out_of_memory(cinfo, 4); /* jpeg_get_large failed */
+ mem->total_space_allocated += sizeofobject + SIZEOF(large_pool_hdr);
+
+ /* Success, initialize the new pool header and add to list */
+ hdr_ptr->hdr.next = mem->large_list[pool_id];
+ /* We maintain space counts in each pool header for statistical purposes,
+ * even though they are not needed for allocation.
+ */
+ hdr_ptr->hdr.bytes_used = sizeofobject;
+ hdr_ptr->hdr.bytes_left = 0;
+ mem->large_list[pool_id] = hdr_ptr;
+
+ return (void FAR *) (hdr_ptr + 1); /* point to first data byte in pool */
+}
+
+
+/*
+ * Creation of 2-D sample arrays.
+ * The pointers are in near heap, the samples themselves in FAR heap.
+ *
+ * To minimize allocation overhead and to allow I/O of large contiguous
+ * blocks, we allocate the sample rows in groups of as many rows as possible
+ * without exceeding MAX_ALLOC_CHUNK total bytes per allocation request.
+ * NB: the virtual array control routines, later in this file, know about
+ * this chunking of rows. The rowsperchunk value is left in the mem manager
+ * object so that it can be saved away if this sarray is the workspace for
+ * a virtual array.
+ */
+
+METHODDEF JSAMPARRAY
+alloc_sarray (j_common_ptr cinfo, int pool_id,
+ JDIMENSION samplesperrow, JDIMENSION numrows)
+/* Allocate a 2-D sample array */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ JSAMPARRAY result;
+ JSAMPROW workspace;
+ JDIMENSION rowsperchunk, currow, i;
+ long ltemp;
+
+ /* Calculate max # of rows allowed in one allocation chunk */
+ ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
+ ((long) samplesperrow * SIZEOF(JSAMPLE));
+ if (ltemp <= 0)
+ ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
+ if (ltemp < (long) numrows)
+ rowsperchunk = (JDIMENSION) ltemp;
+ else
+ rowsperchunk = numrows;
+ mem->last_rowsperchunk = rowsperchunk;
+
+ /* Get space for row pointers (small object) */
+ result = (JSAMPARRAY) alloc_small(cinfo, pool_id,
+ (size_t) (numrows * SIZEOF(JSAMPROW)));
+
+ /* Get the rows themselves (large objects) */
+ currow = 0;
+ while (currow < numrows) {
+ rowsperchunk = MIN(rowsperchunk, numrows - currow);
+ workspace = (JSAMPROW) alloc_large(cinfo, pool_id,
+ (size_t) ((size_t) rowsperchunk * (size_t) samplesperrow
+ * SIZEOF(JSAMPLE)));
+ for (i = rowsperchunk; i > 0; i--) {
+ result[currow++] = workspace;
+ workspace += samplesperrow;
+ }
+ }
+
+ return result;
+}
+
+
+/*
+ * Creation of 2-D coefficient-block arrays.
+ * This is essentially the same as the code for sample arrays, above.
+ */
+
+METHODDEF JBLOCKARRAY
+alloc_barray (j_common_ptr cinfo, int pool_id,
+ JDIMENSION blocksperrow, JDIMENSION numrows)
+/* Allocate a 2-D coefficient-block array */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ JBLOCKARRAY result;
+ JBLOCKROW workspace;
+ JDIMENSION rowsperchunk, currow, i;
+ long ltemp;
+
+ /* Calculate max # of rows allowed in one allocation chunk */
+ ltemp = (MAX_ALLOC_CHUNK-SIZEOF(large_pool_hdr)) /
+ ((long) blocksperrow * SIZEOF(JBLOCK));
+ if (ltemp <= 0)
+ ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
+ if (ltemp < (long) numrows)
+ rowsperchunk = (JDIMENSION) ltemp;
+ else
+ rowsperchunk = numrows;
+ mem->last_rowsperchunk = rowsperchunk;
+
+ /* Get space for row pointers (small object) */
+ result = (JBLOCKARRAY) alloc_small(cinfo, pool_id,
+ (size_t) (numrows * SIZEOF(JBLOCKROW)));
+
+ /* Get the rows themselves (large objects) */
+ currow = 0;
+ while (currow < numrows) {
+ rowsperchunk = MIN(rowsperchunk, numrows - currow);
+ workspace = (JBLOCKROW) alloc_large(cinfo, pool_id,
+ (size_t) ((size_t) rowsperchunk * (size_t) blocksperrow
+ * SIZEOF(JBLOCK)));
+ for (i = rowsperchunk; i > 0; i--) {
+ result[currow++] = workspace;
+ workspace += blocksperrow;
+ }
+ }
+
+ return result;
+}
+
+
+/*
+ * About virtual array management:
+ *
+ * The above "normal" array routines are only used to allocate strip buffers
+ * (as wide as the image, but just a few rows high). Full-image-sized buffers
+ * are handled as "virtual" arrays. The array is still accessed a strip at a
+ * time, but the memory manager must save the whole array for repeated
+ * accesses. The intended implementation is that there is a strip buffer in
+ * memory (as high as is possible given the desired memory limit), plus a
+ * backing file that holds the rest of the array.
+ *
+ * The request_virt_array routines are told the total size of the image and
+ * the maximum number of rows that will be accessed at once. The in-memory
+ * buffer must be at least as large as the maxaccess value.
+ *
+ * The request routines create control blocks but not the in-memory buffers.
+ * That is postponed until realize_virt_arrays is called. At that time the
+ * total amount of space needed is known (approximately, anyway), so free
+ * memory can be divided up fairly.
+ *
+ * The access_virt_array routines are responsible for making a specific strip
+ * area accessible (after reading or writing the backing file, if necessary).
+ * Note that the access routines are told whether the caller intends to modify
+ * the accessed strip; during a read-only pass this saves having to rewrite
+ * data to disk. The access routines are also responsible for pre-zeroing
+ * any newly accessed rows, if pre-zeroing was requested.
+ *
+ * In current usage, the access requests are usually for nonoverlapping
+ * strips; that is, successive access start_row numbers differ by exactly
+ * num_rows = maxaccess. This means we can get good performance with simple
+ * buffer dump/reload logic, by making the in-memory buffer be a multiple
+ * of the access height; then there will never be accesses across bufferload
+ * boundaries. The code will still work with overlapping access requests,
+ * but it doesn't handle bufferload overlaps very efficiently.
+ */
+
+
+METHODDEF jvirt_sarray_ptr
+request_virt_sarray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
+ JDIMENSION samplesperrow, JDIMENSION numrows,
+ JDIMENSION maxaccess)
+/* Request a virtual 2-D sample array */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ jvirt_sarray_ptr result;
+
+ /* Only IMAGE-lifetime virtual arrays are currently supported */
+ if (pool_id != JPOOL_IMAGE)
+ ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
+
+ /* get control block */
+ result = (jvirt_sarray_ptr) alloc_small(cinfo, pool_id,
+ SIZEOF(struct jvirt_sarray_control));
+
+ result->mem_buffer = NULL; /* marks array not yet realized */
+ result->rows_in_array = numrows;
+ result->samplesperrow = samplesperrow;
+ result->maxaccess = maxaccess;
+ result->pre_zero = pre_zero;
+ result->b_s_open = FALSE; /* no associated backing-store object */
+ result->next = mem->virt_sarray_list; /* add to list of virtual arrays */
+ mem->virt_sarray_list = result;
+
+ return result;
+}
+
+
+METHODDEF jvirt_barray_ptr
+request_virt_barray (j_common_ptr cinfo, int pool_id, boolean pre_zero,
+ JDIMENSION blocksperrow, JDIMENSION numrows,
+ JDIMENSION maxaccess)
+/* Request a virtual 2-D coefficient-block array */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ jvirt_barray_ptr result;
+
+ /* Only IMAGE-lifetime virtual arrays are currently supported */
+ if (pool_id != JPOOL_IMAGE)
+ ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
+
+ /* get control block */
+ result = (jvirt_barray_ptr) alloc_small(cinfo, pool_id,
+ SIZEOF(struct jvirt_barray_control));
+
+ result->mem_buffer = NULL; /* marks array not yet realized */
+ result->rows_in_array = numrows;
+ result->blocksperrow = blocksperrow;
+ result->maxaccess = maxaccess;
+ result->pre_zero = pre_zero;
+ result->b_s_open = FALSE; /* no associated backing-store object */
+ result->next = mem->virt_barray_list; /* add to list of virtual arrays */
+ mem->virt_barray_list = result;
+
+ return result;
+}
+
+
+METHODDEF void
+realize_virt_arrays (j_common_ptr cinfo)
+/* Allocate the in-memory buffers for any unrealized virtual arrays */
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ long space_per_minheight, maximum_space, avail_mem;
+ long minheights, max_minheights;
+ jvirt_sarray_ptr sptr;
+ jvirt_barray_ptr bptr;
+
+ /* Compute the minimum space needed (maxaccess rows in each buffer)
+ * and the maximum space needed (full image height in each buffer).
+ * These may be of use to the system-dependent jpeg_mem_available routine.
+ */
+ space_per_minheight = 0;
+ maximum_space = 0;
+ for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
+ if (sptr->mem_buffer == NULL) { /* if not realized yet */
+ space_per_minheight += (long) sptr->maxaccess *
+ (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
+ maximum_space += (long) sptr->rows_in_array *
+ (long) sptr->samplesperrow * SIZEOF(JSAMPLE);
+ }
+ }
+ for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
+ if (bptr->mem_buffer == NULL) { /* if not realized yet */
+ space_per_minheight += (long) bptr->maxaccess *
+ (long) bptr->blocksperrow * SIZEOF(JBLOCK);
+ maximum_space += (long) bptr->rows_in_array *
+ (long) bptr->blocksperrow * SIZEOF(JBLOCK);
+ }
+ }
+
+ if (space_per_minheight <= 0)
+ return; /* no unrealized arrays, no work */
+
+ /* Determine amount of memory to actually use; this is system-dependent. */
+ avail_mem = jpeg_mem_available(cinfo, space_per_minheight, maximum_space,
+ mem->total_space_allocated);
+
+ /* If the maximum space needed is available, make all the buffers full
+ * height; otherwise parcel it out with the same number of minheights
+ * in each buffer.
+ */
+ if (avail_mem >= maximum_space)
+ max_minheights = 1000000000L;
+ else {
+ max_minheights = avail_mem / space_per_minheight;
+ /* If there doesn't seem to be enough space, try to get the minimum
+ * anyway. This allows a "stub" implementation of jpeg_mem_available().
+ */
+ if (max_minheights <= 0)
+ max_minheights = 1;
+ }
+
+ /* Allocate the in-memory buffers and initialize backing store as needed. */
+
+ for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
+ if (sptr->mem_buffer == NULL) { /* if not realized yet */
+ minheights = ((long) sptr->rows_in_array - 1L) / sptr->maxaccess + 1L;
+ if (minheights <= max_minheights) {
+ /* This buffer fits in memory */
+ sptr->rows_in_mem = sptr->rows_in_array;
+ } else {
+ /* It doesn't fit in memory, create backing store. */
+ sptr->rows_in_mem = (JDIMENSION) (max_minheights * sptr->maxaccess);
+ jpeg_open_backing_store(cinfo, & sptr->b_s_info,
+ (long) sptr->rows_in_array *
+ (long) sptr->samplesperrow *
+ (long) SIZEOF(JSAMPLE));
+ sptr->b_s_open = TRUE;
+ }
+ sptr->mem_buffer = alloc_sarray(cinfo, JPOOL_IMAGE,
+ sptr->samplesperrow, sptr->rows_in_mem);
+ sptr->rowsperchunk = mem->last_rowsperchunk;
+ sptr->cur_start_row = 0;
+ sptr->first_undef_row = 0;
+ sptr->dirty = FALSE;
+ }
+ }
+
+ for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
+ if (bptr->mem_buffer == NULL) { /* if not realized yet */
+ minheights = ((long) bptr->rows_in_array - 1L) / bptr->maxaccess + 1L;
+ if (minheights <= max_minheights) {
+ /* This buffer fits in memory */
+ bptr->rows_in_mem = bptr->rows_in_array;
+ } else {
+ /* It doesn't fit in memory, create backing store. */
+ bptr->rows_in_mem = (JDIMENSION) (max_minheights * bptr->maxaccess);
+ jpeg_open_backing_store(cinfo, & bptr->b_s_info,
+ (long) bptr->rows_in_array *
+ (long) bptr->blocksperrow *
+ (long) SIZEOF(JBLOCK));
+ bptr->b_s_open = TRUE;
+ }
+ bptr->mem_buffer = alloc_barray(cinfo, JPOOL_IMAGE,
+ bptr->blocksperrow, bptr->rows_in_mem);
+ bptr->rowsperchunk = mem->last_rowsperchunk;
+ bptr->cur_start_row = 0;
+ bptr->first_undef_row = 0;
+ bptr->dirty = FALSE;
+ }
+ }
+}
+
+
+LOCAL void
+do_sarray_io (j_common_ptr cinfo, jvirt_sarray_ptr ptr, boolean writing)
+/* Do backing store read or write of a virtual sample array */
+{
+ long bytesperrow, file_offset, byte_count, rows, thisrow, i;
+
+ bytesperrow = (long) ptr->samplesperrow * SIZEOF(JSAMPLE);
+ file_offset = ptr->cur_start_row * bytesperrow;
+ /* Loop to read or write each allocation chunk in mem_buffer */
+ for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
+ /* One chunk, but check for short chunk at end of buffer */
+ rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
+ /* Transfer no more than is currently defined */
+ thisrow = (long) ptr->cur_start_row + i;
+ rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
+ /* Transfer no more than fits in file */
+ rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
+ if (rows <= 0) /* this chunk might be past end of file! */
+ break;
+ byte_count = rows * bytesperrow;
+ if (writing)
+ (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
+ (void FAR *) ptr->mem_buffer[i],
+ file_offset, byte_count);
+ else
+ (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
+ (void FAR *) ptr->mem_buffer[i],
+ file_offset, byte_count);
+ file_offset += byte_count;
+ }
+}
+
+
+LOCAL void
+do_barray_io (j_common_ptr cinfo, jvirt_barray_ptr ptr, boolean writing)
+/* Do backing store read or write of a virtual coefficient-block array */
+{
+ long bytesperrow, file_offset, byte_count, rows, thisrow, i;
+
+ bytesperrow = (long) ptr->blocksperrow * SIZEOF(JBLOCK);
+ file_offset = ptr->cur_start_row * bytesperrow;
+ /* Loop to read or write each allocation chunk in mem_buffer */
+ for (i = 0; i < (long) ptr->rows_in_mem; i += ptr->rowsperchunk) {
+ /* One chunk, but check for short chunk at end of buffer */
+ rows = MIN((long) ptr->rowsperchunk, (long) ptr->rows_in_mem - i);
+ /* Transfer no more than is currently defined */
+ thisrow = (long) ptr->cur_start_row + i;
+ rows = MIN(rows, (long) ptr->first_undef_row - thisrow);
+ /* Transfer no more than fits in file */
+ rows = MIN(rows, (long) ptr->rows_in_array - thisrow);
+ if (rows <= 0) /* this chunk might be past end of file! */
+ break;
+ byte_count = rows * bytesperrow;
+ if (writing)
+ (*ptr->b_s_info.write_backing_store) (cinfo, & ptr->b_s_info,
+ (void FAR *) ptr->mem_buffer[i],
+ file_offset, byte_count);
+ else
+ (*ptr->b_s_info.read_backing_store) (cinfo, & ptr->b_s_info,
+ (void FAR *) ptr->mem_buffer[i],
+ file_offset, byte_count);
+ file_offset += byte_count;
+ }
+}
+
+
+METHODDEF JSAMPARRAY
+access_virt_sarray (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
+ JDIMENSION start_row, JDIMENSION num_rows,
+ boolean writable)
+/* Access the part of a virtual sample array starting at start_row */
+/* and extending for num_rows rows. writable is true if */
+/* caller intends to modify the accessed area. */
+{
+ JDIMENSION end_row = start_row + num_rows;
+ JDIMENSION undef_row;
+
+ /* debugging check */
+ if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
+ ptr->mem_buffer == NULL)
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+
+ /* Make the desired part of the virtual array accessible */
+ if (start_row < ptr->cur_start_row ||
+ end_row > ptr->cur_start_row+ptr->rows_in_mem) {
+ if (! ptr->b_s_open)
+ ERREXIT(cinfo, JERR_VIRTUAL_BUG);
+ /* Flush old buffer contents if necessary */
+ if (ptr->dirty) {
+ do_sarray_io(cinfo, ptr, TRUE);
+ ptr->dirty = FALSE;
+ }
+ /* Decide what part of virtual array to access.
+ * Algorithm: if target address > current window, assume forward scan,
+ * load starting at target address. If target address < current window,
+ * assume backward scan, load so that target area is top of window.
+ * Note that when switching from forward write to forward read, will have
+ * start_row = 0, so the limiting case applies and we load from 0 anyway.
+ */
+ if (start_row > ptr->cur_start_row) {
+ ptr->cur_start_row = start_row;
+ } else {
+ /* use long arithmetic here to avoid overflow & unsigned problems */
+ long ltemp;
+
+ ltemp = (long) end_row - (long) ptr->rows_in_mem;
+ if (ltemp < 0)
+ ltemp = 0; /* don't fall off front end of file */
+ ptr->cur_start_row = (JDIMENSION) ltemp;
+ }
+ /* Read in the selected part of the array.
+ * During the initial write pass, we will do no actual read
+ * because the selected part is all undefined.
+ */
+ do_sarray_io(cinfo, ptr, FALSE);
+ }
+ /* Ensure the accessed part of the array is defined; prezero if needed.
+ * To improve locality of access, we only prezero the part of the array
+ * that the caller is about to access, not the entire in-memory array.
+ */
+ if (ptr->first_undef_row < end_row) {
+ if (ptr->first_undef_row < start_row) {
+ if (writable) /* writer skipped over a section of array */
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+ undef_row = start_row; /* but reader is allowed to read ahead */
+ } else {
+ undef_row = ptr->first_undef_row;
+ }
+ if (writable)
+ ptr->first_undef_row = end_row;
+ if (ptr->pre_zero) {
+ size_t bytesperrow = (size_t) ptr->samplesperrow * SIZEOF(JSAMPLE);
+ undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
+ end_row -= ptr->cur_start_row;
+ while (undef_row < end_row) {
+ jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
+ undef_row++;
+ }
+ } else {
+ if (! writable) /* reader looking at undefined data */
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+ }
+ }
+ /* Flag the buffer dirty if caller will write in it */
+ if (writable)
+ ptr->dirty = TRUE;
+ /* Return address of proper part of the buffer */
+ return ptr->mem_buffer + (start_row - ptr->cur_start_row);
+}
+
+
+METHODDEF JBLOCKARRAY
+access_virt_barray (j_common_ptr cinfo, jvirt_barray_ptr ptr,
+ JDIMENSION start_row, JDIMENSION num_rows,
+ boolean writable)
+/* Access the part of a virtual block array starting at start_row */
+/* and extending for num_rows rows. writable is true if */
+/* caller intends to modify the accessed area. */
+{
+ JDIMENSION end_row = start_row + num_rows;
+ JDIMENSION undef_row;
+
+ /* debugging check */
+ if (end_row > ptr->rows_in_array || num_rows > ptr->maxaccess ||
+ ptr->mem_buffer == NULL)
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+
+ /* Make the desired part of the virtual array accessible */
+ if (start_row < ptr->cur_start_row ||
+ end_row > ptr->cur_start_row+ptr->rows_in_mem) {
+ if (! ptr->b_s_open)
+ ERREXIT(cinfo, JERR_VIRTUAL_BUG);
+ /* Flush old buffer contents if necessary */
+ if (ptr->dirty) {
+ do_barray_io(cinfo, ptr, TRUE);
+ ptr->dirty = FALSE;
+ }
+ /* Decide what part of virtual array to access.
+ * Algorithm: if target address > current window, assume forward scan,
+ * load starting at target address. If target address < current window,
+ * assume backward scan, load so that target area is top of window.
+ * Note that when switching from forward write to forward read, will have
+ * start_row = 0, so the limiting case applies and we load from 0 anyway.
+ */
+ if (start_row > ptr->cur_start_row) {
+ ptr->cur_start_row = start_row;
+ } else {
+ /* use long arithmetic here to avoid overflow & unsigned problems */
+ long ltemp;
+
+ ltemp = (long) end_row - (long) ptr->rows_in_mem;
+ if (ltemp < 0)
+ ltemp = 0; /* don't fall off front end of file */
+ ptr->cur_start_row = (JDIMENSION) ltemp;
+ }
+ /* Read in the selected part of the array.
+ * During the initial write pass, we will do no actual read
+ * because the selected part is all undefined.
+ */
+ do_barray_io(cinfo, ptr, FALSE);
+ }
+ /* Ensure the accessed part of the array is defined; prezero if needed.
+ * To improve locality of access, we only prezero the part of the array
+ * that the caller is about to access, not the entire in-memory array.
+ */
+ if (ptr->first_undef_row < end_row) {
+ if (ptr->first_undef_row < start_row) {
+ if (writable) /* writer skipped over a section of array */
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+ undef_row = start_row; /* but reader is allowed to read ahead */
+ } else {
+ undef_row = ptr->first_undef_row;
+ }
+ if (writable)
+ ptr->first_undef_row = end_row;
+ if (ptr->pre_zero) {
+ size_t bytesperrow = (size_t) ptr->blocksperrow * SIZEOF(JBLOCK);
+ undef_row -= ptr->cur_start_row; /* make indexes relative to buffer */
+ end_row -= ptr->cur_start_row;
+ while (undef_row < end_row) {
+ jzero_far((void FAR *) ptr->mem_buffer[undef_row], bytesperrow);
+ undef_row++;
+ }
+ } else {
+ if (! writable) /* reader looking at undefined data */
+ ERREXIT(cinfo, JERR_BAD_VIRTUAL_ACCESS);
+ }
+ }
+ /* Flag the buffer dirty if caller will write in it */
+ if (writable)
+ ptr->dirty = TRUE;
+ /* Return address of proper part of the buffer */
+ return ptr->mem_buffer + (start_row - ptr->cur_start_row);
+}
+
+
+/*
+ * Release all objects belonging to a specified pool.
+ */
+
+METHODDEF void
+free_pool (j_common_ptr cinfo, int pool_id)
+{
+ my_mem_ptr mem = (my_mem_ptr) cinfo->mem;
+ small_pool_ptr shdr_ptr;
+ large_pool_ptr lhdr_ptr;
+ size_t space_freed;
+
+ if (pool_id < 0 || pool_id >= JPOOL_NUMPOOLS)
+ ERREXIT1(cinfo, JERR_BAD_POOL_ID, pool_id); /* safety check */
+
+#ifdef MEM_STATS
+ if (cinfo->err->trace_level > 1)
+ print_mem_stats(cinfo, pool_id); /* print pool's memory usage statistics */
+#endif
+
+ /* If freeing IMAGE pool, close any virtual arrays first */
+ if (pool_id == JPOOL_IMAGE) {
+ jvirt_sarray_ptr sptr;
+ jvirt_barray_ptr bptr;
+
+ for (sptr = mem->virt_sarray_list; sptr != NULL; sptr = sptr->next) {
+ if (sptr->b_s_open) { /* there may be no backing store */
+ sptr->b_s_open = FALSE; /* prevent recursive close if error */
+ (*sptr->b_s_info.close_backing_store) (cinfo, & sptr->b_s_info);
+ }
+ }
+ mem->virt_sarray_list = NULL;
+ for (bptr = mem->virt_barray_list; bptr != NULL; bptr = bptr->next) {
+ if (bptr->b_s_open) { /* there may be no backing store */
+ bptr->b_s_open = FALSE; /* prevent recursive close if error */
+ (*bptr->b_s_info.close_backing_store) (cinfo, & bptr->b_s_info);
+ }
+ }
+ mem->virt_barray_list = NULL;
+ }
+
+ /* Release large objects */
+ lhdr_ptr = mem->large_list[pool_id];
+ mem->large_list[pool_id] = NULL;
+
+ while (lhdr_ptr != NULL) {
+ large_pool_ptr next_lhdr_ptr = lhdr_ptr->hdr.next;
+ space_freed = lhdr_ptr->hdr.bytes_used +
+ lhdr_ptr->hdr.bytes_left +
+ SIZEOF(large_pool_hdr);
+ jpeg_free_large(cinfo, (void FAR *) lhdr_ptr, space_freed);
+ mem->total_space_allocated -= space_freed;
+ lhdr_ptr = next_lhdr_ptr;
+ }
+
+ /* Release small objects */
+ shdr_ptr = mem->small_list[pool_id];
+ mem->small_list[pool_id] = NULL;
+
+ while (shdr_ptr != NULL) {
+ small_pool_ptr next_shdr_ptr = shdr_ptr->hdr.next;
+ space_freed = shdr_ptr->hdr.bytes_used +
+ shdr_ptr->hdr.bytes_left +
+ SIZEOF(small_pool_hdr);
+ jpeg_free_small(cinfo, (void *) shdr_ptr, space_freed);
+ mem->total_space_allocated -= space_freed;
+ shdr_ptr = next_shdr_ptr;
+ }
+}
+
+
+/*
+ * Close up shop entirely.
+ * Note that this cannot be called unless cinfo->mem is non-NULL.
+ */
+
+METHODDEF void
+self_destruct (j_common_ptr cinfo)
+{
+ int pool;
+
+ /* Close all backing store, release all memory.
+ * Releasing pools in reverse order might help avoid fragmentation
+ * with some (brain-damaged) malloc libraries.
+ */
+ for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
+ free_pool(cinfo, pool);
+ }
+
+ /* Release the memory manager control block too. */
+ jpeg_free_small(cinfo, (void *) cinfo->mem, SIZEOF(my_memory_mgr));
+ cinfo->mem = NULL; /* ensures I will be called only once */
+
+ jpeg_mem_term(cinfo); /* system-dependent cleanup */
+}
+
+
+/*
+ * Memory manager initialization.
+ * When this is called, only the error manager pointer is valid in cinfo!
+ */
+
+GLOBAL void
+jinit_memory_mgr (j_common_ptr cinfo)
+{
+ my_mem_ptr mem;
+ long max_to_use;
+ int pool;
+ size_t test_mac;
+
+ cinfo->mem = NULL; /* for safety if init fails */
+
+ /* Check for configuration errors.
+ * SIZEOF(ALIGN_TYPE) should be a power of 2; otherwise, it probably
+ * doesn't reflect any real hardware alignment requirement.
+ * The test is a little tricky: for X>0, X and X-1 have no one-bits
+ * in common if and only if X is a power of 2, ie has only one one-bit.
+ * Some compilers may give an "unreachable code" warning here; ignore it.
+ */
+ if ((SIZEOF(ALIGN_TYPE) & (SIZEOF(ALIGN_TYPE)-1)) != 0)
+ ERREXIT(cinfo, JERR_BAD_ALIGN_TYPE);
+ /* MAX_ALLOC_CHUNK must be representable as type size_t, and must be
+ * a multiple of SIZEOF(ALIGN_TYPE).
+ * Again, an "unreachable code" warning may be ignored here.
+ * But a "constant too large" warning means you need to fix MAX_ALLOC_CHUNK.
+ */
+ test_mac = (size_t) MAX_ALLOC_CHUNK;
+ if ((long) test_mac != MAX_ALLOC_CHUNK ||
+ (MAX_ALLOC_CHUNK % SIZEOF(ALIGN_TYPE)) != 0)
+ ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
+
+ max_to_use = jpeg_mem_init(cinfo); /* system-dependent initialization */
+
+ /* Attempt to allocate memory manager's control block */
+ mem = (my_mem_ptr) jpeg_get_small(cinfo, SIZEOF(my_memory_mgr));
+
+ if (mem == NULL) {
+ jpeg_mem_term(cinfo); /* system-dependent cleanup */
+ ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 0);
+ }
+
+ /* OK, fill in the method pointers */
+ mem->pub.alloc_small = alloc_small;
+ mem->pub.alloc_large = alloc_large;
+ mem->pub.alloc_sarray = alloc_sarray;
+ mem->pub.alloc_barray = alloc_barray;
+ mem->pub.request_virt_sarray = request_virt_sarray;
+ mem->pub.request_virt_barray = request_virt_barray;
+ mem->pub.realize_virt_arrays = realize_virt_arrays;
+ mem->pub.access_virt_sarray = access_virt_sarray;
+ mem->pub.access_virt_barray = access_virt_barray;
+ mem->pub.free_pool = free_pool;
+ mem->pub.self_destruct = self_destruct;
+
+ /* Initialize working state */
+ mem->pub.max_memory_to_use = max_to_use;
+
+ for (pool = JPOOL_NUMPOOLS-1; pool >= JPOOL_PERMANENT; pool--) {
+ mem->small_list[pool] = NULL;
+ mem->large_list[pool] = NULL;
+ }
+ mem->virt_sarray_list = NULL;
+ mem->virt_barray_list = NULL;
+
+ mem->total_space_allocated = SIZEOF(my_memory_mgr);
+
+ /* Declare ourselves open for business */
+ cinfo->mem = & mem->pub;
+
+ /* Check for an environment variable JPEGMEM; if found, override the
+ * default max_memory setting from jpeg_mem_init. Note that the
+ * surrounding application may again override this value.
+ * If your system doesn't support getenv(), define NO_GETENV to disable
+ * this feature.
+ */
+#ifndef NO_GETENV
+ { char * memenv;
+
+ if ((memenv = getenv("JPEGMEM")) != NULL) {
+ char ch = 'x';
+
+ if (sscanf(memenv, "%ld%c", &max_to_use, &ch) > 0) {
+ if (ch == 'm' || ch == 'M')
+ max_to_use *= 1000L;
+ mem->pub.max_memory_to_use = max_to_use * 1000L;
+ }
+ }
+ }
+#endif
+
+}
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