Changeset 27

Timestamp:

06/10/06 21:01:32 (2 years ago)

Author:

scott

Message:

Refactored apool memory pool

• Doubling is now done through apool_expand()
• Initialization is now done through apool_expand()
• Added alias apool_double() which maps to apool_expand

Location:

trunk/libapool

Files:

• apool.c (modified) (3 diffs)
• apool.h (modified) (1 diff)

trunk/libapool/apool.c

@@ -3 +3 @@
 #include "apool.h"
 
-apool * apool_new (size_t blocks, size_t blocksize) {
-    apool *pool = malloc(sizeof(apool));
+#define apool_double(pool) apool_expand(pool, pool->blocks)
+
+void apool_expand (apool *pool, size_t blocks) {
+    size_t blocksize = pool->blocksize;
     struct chunk *chunk = malloc(sizeof(struct chunk));
 
-    chunk->next = NULL;
+    chunk->next = pool->chunk;
     pool->chunk = chunk;
 
     char *ram = chunk->chunk = calloc(blocks, blocksize);
 
+    /* Stack must be able to hold atleast all available items */
+    free(pool->stack);
+    pool->blocks += blocks;
+    pool->stack = calloc(pool->blocks, sizeof(void *));
+    pool->pos += (int) blocks;
+
+    /* Use the ram in reverse order */
+    ram += (blocks - 1) * blocksize;
+    for (size_t i = 0; i < blocks; ram -= blocksize) {
+        pool->stack[i++] = ram;
+    }
+}
+
+apool * apool_new (size_t blocks, size_t blocksize) {
+    apool *pool = malloc(sizeof(apool));
+
     pool->blocksize = blocksize;
-    pool->blocks = blocks;
-    pool->heap = calloc(blocks, sizeof(void *));
-    pool->pos = (int) blocks;
+    pool->blocks = 0;
+    pool->pos = 0;
+    pool->stack = NULL; /* We have no data, free(null) is ok */
+    pool->chunk = NULL; /* We must initialize pool->chunk so it's stored */
 
-    for (size_t i = 0; i < blocks; i++) {
-        pool->heap[i] = ram;
-        ram += blocksize;
-    }
+    apool_expand(pool, blocks);
 
     return pool;
-}
-
-/* Double the size of the pool */
-void apool_double (apool *pool) {
-    size_t blocks = pool->blocks,
-           blocksize = pool->blocksize;
-
-    struct chunk *chunk = malloc(sizeof(struct chunk));
-    chunk->next = pool->chunk;
-    pool->chunk = chunk;
-
-    char *ram = chunk->chunk = malloc(blocks * blocksize);
-
-    /* Our new position */
-    pool->pos = (int) blocks;
-
-    /* This may look strange, but we're freeing the array of pointers.  I use
-     * free and calloc instead of realloc because my stack is empty, I don't
-     * care about any data in this. */
-    free(pool->heap);
-
-    pool->blocks *= 2;
-    pool->heap = calloc(pool->blocks, sizeof(void *));
-
-    for (size_t i = 0; i < blocks; i++) {
-        pool->heap[i] = ram;
-        ram += blocksize;
-    }
 }
 
@@ -69 +57 @@
     }
 
-    free(pool->heap);
+    free(pool->stack);
     free(pool);
 }
@@ -78 +66 @@
     }
 
-    return pool->heap[--pool->pos];
+    return pool->stack[--pool->pos];
 }
 
 void apool_free (apool *pool, void * chunk) {
-    pool->heap[pool->pos++] = chunk;
+    pool->stack[pool->pos++] = chunk;
 }

trunk/libapool/apool.h

@@ -10 +10 @@
     size_t blocksize;
     size_t blocks;
-    void **heap;
+    void **stack;
     struct chunk *chunk;
 } apool;
 
 extern apool * apool_new (size_t blocks, size_t blocksize);
+extern void apool_expand (apool *pool, size_t blocks);
+extern void apool_dobule (apool *pool);
 extern void apool_destroy (apool *pool);
-
-/* Double the size of the pool */
-extern void apool_double (apool *pool);
-
 extern void * apool_alloc (apool *pool);
-
 extern void apool_free (apool *pool, void * chunk);