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-rw-r--r--Build/source/libs/cairo/cairo-1.12.8/src/cairo-mempool.c359
1 files changed, 359 insertions, 0 deletions
diff --git a/Build/source/libs/cairo/cairo-1.12.8/src/cairo-mempool.c b/Build/source/libs/cairo/cairo-1.12.8/src/cairo-mempool.c
new file mode 100644
index 00000000000..296b7393236
--- /dev/null
+++ b/Build/source/libs/cairo/cairo-1.12.8/src/cairo-mempool.c
@@ -0,0 +1,359 @@
+/* Cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2007 Chris Wilson
+ * Copyright © 2009 Intel Corporation
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipoolent may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is Red Hat, Inc.
+ *
+ * Contributors(s):
+ * Chris Wilson <chris@chris-wilson.co.uk>
+ */
+
+#include "cairoint.h"
+
+#include "cairo-mempool-private.h"
+#include "cairo-list-inline.h"
+
+/* a simple buddy allocator for memory pools
+ * XXX fragmentation? use Doug Lea's malloc?
+ */
+
+#define BITTEST(p, n) ((p)->map[(n) >> 3] & (128 >> ((n) & 7)))
+#define BITSET(p, n) ((p)->map[(n) >> 3] |= (128 >> ((n) & 7)))
+#define BITCLEAR(p, n) ((p)->map[(n) >> 3] &= ~(128 >> ((n) & 7)))
+
+static void
+clear_bits (cairo_mempool_t *pool, size_t first, size_t last)
+{
+ size_t i, n = last;
+ size_t first_full = (first + 7) & ~7;
+ size_t past_full = last & ~7;
+ size_t bytes;
+
+ if (n > first_full)
+ n = first_full;
+ for (i = first; i < n; i++)
+ BITCLEAR (pool, i);
+
+ if (past_full > first_full) {
+ bytes = past_full - first_full;
+ bytes = bytes >> 3;
+ memset (pool->map + (first_full >> 3), 0, bytes);
+ }
+
+ if (past_full < n)
+ past_full = n;
+ for (i = past_full; i < last; i++)
+ BITCLEAR (pool, i);
+}
+
+static void
+free_bits (cairo_mempool_t *pool, size_t start, int bits, cairo_bool_t clear)
+{
+ struct _cairo_memblock *block;
+
+ if (clear)
+ clear_bits (pool, start, start + (1 << bits));
+
+ block = pool->blocks + start;
+ block->bits = bits;
+
+ cairo_list_add (&block->link, &pool->free[bits]);
+
+ pool->free_bytes += 1 << (bits + pool->min_bits);
+ if (bits > pool->max_free_bits)
+ pool->max_free_bits = bits;
+}
+
+/* Add a chunk to the free list */
+static void
+free_blocks (cairo_mempool_t *pool,
+ size_t first,
+ size_t last,
+ cairo_bool_t clear)
+{
+ size_t i, len;
+ int bits = 0;
+
+ for (i = first, len = 1; i < last; i += len) {
+ /* To avoid cost quadratic in the number of different
+ * blocks produced from this chunk of store, we have to
+ * use the size of the previous block produced from this
+ * chunk as the starting point to work out the size of the
+ * next block we can produce. If you look at the binary
+ * representation of the starting points of the blocks
+ * produced, you can see that you first of all increase the
+ * size of the blocks produced up to some maximum as the
+ * address dealt with gets offsets added on which zap out
+ * low order bits, then decrease as the low order bits of the
+ * final block produced get added in. E.g. as you go from
+ * 001 to 0111 you generate blocks
+ * of size 001 at 001 taking you to 010
+ * of size 010 at 010 taking you to 100
+ * of size 010 at 100 taking you to 110
+ * of size 001 at 110 taking you to 111
+ * So the maximum total cost of the loops below this comment
+ * is one trip from the lowest blocksize to the highest and
+ * back again.
+ */
+ while (bits < pool->num_sizes - 1) {
+ size_t next_bits = bits + 1;
+ size_t next_len = len << 1;
+
+ if (i + next_bits > last) {
+ /* off end of chunk to be freed */
+ break;
+ }
+
+ if (i & (next_len - 1)) /* block would not be on boundary */
+ break;
+
+ bits = next_bits;
+ len = next_len;
+ }
+
+ do {
+ if (i + len <= last && /* off end of chunk to be freed */
+ (i & (len - 1)) == 0) /* block would not be on boundary */
+ break;
+
+ bits--; len >>=1;
+ } while (len);
+
+ if (len == 0)
+ break;
+
+ free_bits (pool, i, bits, clear);
+ }
+}
+
+static struct _cairo_memblock *
+get_buddy (cairo_mempool_t *pool, size_t offset, int bits)
+{
+ struct _cairo_memblock *block;
+
+ assert (offset + (1 << bits) <= pool->num_blocks);
+
+ if (BITTEST (pool, offset + (1 << bits) - 1))
+ return NULL; /* buddy is allocated */
+
+ block = pool->blocks + offset;
+ if (block->bits != bits)
+ return NULL; /* buddy is partially allocated */
+
+ return block;
+}
+
+static void
+merge_buddies (cairo_mempool_t *pool,
+ struct _cairo_memblock *block,
+ int max_bits)
+{
+ size_t block_offset = block - pool->blocks;
+ int bits = block->bits;
+
+ while (bits < max_bits - 1) {
+ /* while you can, merge two blocks and get a legal block size */
+ size_t buddy_offset = block_offset ^ (1 << bits);
+
+ block = get_buddy (pool, buddy_offset, bits);
+ if (block == NULL)
+ break;
+
+ cairo_list_del (&block->link);
+
+ /* Merged block starts at buddy */
+ if (buddy_offset < block_offset)
+ block_offset = buddy_offset;
+
+ bits++;
+ }
+
+ block = pool->blocks + block_offset;
+ block->bits = bits;
+ cairo_list_add (&block->link, &pool->free[bits]);
+
+ if (bits > pool->max_free_bits)
+ pool->max_free_bits = bits;
+}
+
+/* attempt to merge all available buddies up to a particular size */
+static int
+merge_bits (cairo_mempool_t *pool, int max_bits)
+{
+ struct _cairo_memblock *block, *buddy, *next;
+ int bits;
+
+ for (bits = 0; bits < max_bits - 1; bits++) {
+ cairo_list_foreach_entry_safe (block, next,
+ struct _cairo_memblock,
+ &pool->free[bits],
+ link)
+ {
+ size_t buddy_offset = (block - pool->blocks) ^ (1 << bits);
+
+ buddy = get_buddy (pool, buddy_offset, bits);
+ if (buddy == NULL)
+ continue;
+
+ if (buddy == next) {
+ next = cairo_container_of (buddy->link.next,
+ struct _cairo_memblock,
+ link);
+ }
+
+ cairo_list_del (&block->link);
+ merge_buddies (pool, block, max_bits);
+ }
+ }
+
+ return pool->max_free_bits;
+}
+
+/* find store for 1 << bits blocks */
+static void *
+buddy_malloc (cairo_mempool_t *pool, int bits)
+{
+ size_t past, offset;
+ struct _cairo_memblock *block;
+ int b;
+
+ if (bits > pool->max_free_bits && bits > merge_bits (pool, bits))
+ return NULL;
+
+ /* Find a list with blocks big enough on it */
+ block = NULL;
+ for (b = bits; b <= pool->max_free_bits; b++) {
+ if (! cairo_list_is_empty (&pool->free[b])) {
+ block = cairo_list_first_entry (&pool->free[b],
+ struct _cairo_memblock,
+ link);
+ break;
+ }
+ }
+ assert (block != NULL);
+
+ cairo_list_del (&block->link);
+
+ while (cairo_list_is_empty (&pool->free[pool->max_free_bits])) {
+ if (--pool->max_free_bits == -1)
+ break;
+ }
+
+ /* Mark end of allocated area */
+ offset = block - pool->blocks;
+ past = offset + (1 << bits);
+ BITSET (pool, past - 1);
+ block->bits = bits;
+
+ /* If we used a larger free block than we needed, free the rest */
+ pool->free_bytes -= 1 << (b + pool->min_bits);
+ free_blocks (pool, past, offset + (1 << b), 0);
+
+ return pool->base + ((block - pool->blocks) << pool->min_bits);
+}
+
+cairo_status_t
+_cairo_mempool_init (cairo_mempool_t *pool,
+ void *base, size_t bytes,
+ int min_bits, int num_sizes)
+{
+ int num_blocks;
+ int i;
+
+ assert ((((unsigned long) base) & ((1 << min_bits) - 1)) == 0);
+ assert (num_sizes < ARRAY_LENGTH (pool->free));
+
+ pool->base = base;
+ pool->free_bytes = 0;
+ pool->max_bytes = bytes;
+ pool->max_free_bits = -1;
+
+ num_blocks = bytes >> min_bits;
+ pool->blocks = calloc (num_blocks, sizeof (struct _cairo_memblock));
+ if (pool->blocks == NULL)
+ return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+ pool->num_blocks = num_blocks;
+ pool->min_bits = min_bits;
+ pool->num_sizes = num_sizes;
+
+ for (i = 0; i < ARRAY_LENGTH (pool->free); i++)
+ cairo_list_init (&pool->free[i]);
+
+ pool->map = malloc ((num_blocks + 7) >> 3);
+ if (pool->map == NULL) {
+ free (pool->blocks);
+ return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+ }
+
+ memset (pool->map, -1, (num_blocks + 7) >> 3);
+ clear_bits (pool, 0, num_blocks);
+
+ /* Now add all blocks to the free list */
+ free_blocks (pool, 0, num_blocks, 1);
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+void *
+_cairo_mempool_alloc (cairo_mempool_t *pool, size_t bytes)
+{
+ size_t size;
+ int bits;
+
+ size = 1 << pool->min_bits;
+ for (bits = 0; size < bytes; bits++)
+ size <<= 1;
+ if (bits >= pool->num_sizes)
+ return NULL;
+
+ return buddy_malloc (pool, bits);
+}
+
+void
+_cairo_mempool_free (cairo_mempool_t *pool, void *storage)
+{
+ size_t block_offset;
+ struct _cairo_memblock *block;
+
+ block_offset = ((char *)storage - pool->base) >> pool->min_bits;
+ block = pool->blocks + block_offset;
+
+ BITCLEAR (pool, block_offset + ((1 << block->bits) - 1));
+ pool->free_bytes += 1 << (block->bits + pool->min_bits);
+
+ merge_buddies (pool, block, pool->num_sizes);
+}
+
+void
+_cairo_mempool_fini (cairo_mempool_t *pool)
+{
+ free (pool->map);
+ free (pool->blocks);
+}
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