add initial structure

1 files changed, 242 insertions, 0 deletions

diff --git a/portaudio/src/common/pa_allocation.c b/portaudio/src/common/pa_allocation.c
new file mode 100644
index 0000000..7e3298a
--- /dev/null
+++ b/portaudio/src/common/pa_allocation.c
@@ -0,0 +1,242 @@
+/*
+ * $Id$
+ * Portable Audio I/O Library allocation group implementation
+ * memory allocation group for tracking allocation groups
+ *
+ * Based on the Open Source API proposed by Ross Bencina
+ * Copyright (c) 1999-2002 Ross Bencina, Phil Burk
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * The text above constitutes the entire PortAudio license; however,
+ * the PortAudio community also makes the following non-binding requests:
+ *
+ * Any person wishing to distribute modifications to the Software is
+ * requested to send the modifications to the original developer so that
+ * they can be incorporated into the canonical version. It is also
+ * requested that these non-binding requests be included along with the
+ * license above.
+ */
+
+/** @file
+ @ingroup common_src
+
+ @brief Allocation Group implementation.
+*/
+
+
+#include "pa_allocation.h"
+#include "pa_util.h"
+
+
+/*
+    Maintain 3 singly linked lists...
+    linkBlocks: the buffers used to allocate the links
+    spareLinks: links available for use in the allocations list
+    allocations: the buffers currently allocated using PaUtil_ContextAllocateMemory()
+
+    Link block size is doubled every time new links are allocated.
+*/
+
+
+#define PA_INITIAL_LINK_COUNT_    16
+
+struct PaUtilAllocationGroupLink
+{
+    struct PaUtilAllocationGroupLink *next;
+    void *buffer;
+};
+
+/*
+    Allocate a block of links. The first link will have it's buffer member
+    pointing to the block, and it's next member set to <nextBlock>. The remaining
+    links will have NULL buffer members, and each link will point to
+    the next link except the last, which will point to <nextSpare>
+*/
+static struct PaUtilAllocationGroupLink *AllocateLinks( long count,
+        struct PaUtilAllocationGroupLink *nextBlock,
+        struct PaUtilAllocationGroupLink *nextSpare )
+{
+    struct PaUtilAllocationGroupLink *result;
+    int i;
+
+    result = (struct PaUtilAllocationGroupLink *)PaUtil_AllocateMemory(
+            sizeof(struct PaUtilAllocationGroupLink) * count );
+    if( result )
+    {
+        /* the block link */
+        result[0].buffer = result;
+        result[0].next = nextBlock;
+
+        /* the spare links */
+        for( i=1; i<count; ++i )
+        {
+            result[i].buffer = 0;
+            result[i].next = &result[i+1];
+        }
+        result[count-1].next = nextSpare;
+    }
+
+    return result;
+}
+
+
+PaUtilAllocationGroup* PaUtil_CreateAllocationGroup( void )
+{
+    PaUtilAllocationGroup* result = 0;
+    struct PaUtilAllocationGroupLink *links;
+
+
+    links = AllocateLinks( PA_INITIAL_LINK_COUNT_, 0, 0 );
+    if( links != 0 )
+    {
+        result = (PaUtilAllocationGroup*)PaUtil_AllocateMemory( sizeof(PaUtilAllocationGroup) );
+        if( result )
+        {
+            result->linkCount = PA_INITIAL_LINK_COUNT_;
+            result->linkBlocks = &links[0];
+            result->spareLinks = &links[1];
+            result->allocations = 0;
+        }
+        else
+        {
+            PaUtil_FreeMemory( links );
+        }
+    }
+
+    return result;
+}
+
+
+void PaUtil_DestroyAllocationGroup( PaUtilAllocationGroup* group )
+{
+    struct PaUtilAllocationGroupLink *current = group->linkBlocks;
+    struct PaUtilAllocationGroupLink *next;
+
+    while( current )
+    {
+        next = current->next;
+        PaUtil_FreeMemory( current->buffer );
+        current = next;
+    }
+
+    PaUtil_FreeMemory( group );
+}
+
+
+void* PaUtil_GroupAllocateMemory( PaUtilAllocationGroup* group, long size )
+{
+    struct PaUtilAllocationGroupLink *links, *link;
+    void *result = 0;
+
+    /* allocate more links if necessary */
+    if( !group->spareLinks )
+    {
+        /* double the link count on each block allocation */
+        links = AllocateLinks( group->linkCount, group->linkBlocks, group->spareLinks );
+        if( links )
+        {
+            group->linkCount += group->linkCount;
+            group->linkBlocks = &links[0];
+            group->spareLinks = &links[1];
+        }
+    }
+
+    if( group->spareLinks )
+    {
+        result = PaUtil_AllocateMemory( size );
+        if( result )
+        {
+            link = group->spareLinks;
+            group->spareLinks = link->next;
+
+            link->buffer = result;
+            link->next = group->allocations;
+
+            group->allocations = link;
+        }
+    }
+
+    return result;
+}
+
+
+void PaUtil_GroupFreeMemory( PaUtilAllocationGroup* group, void *buffer )
+{
+    struct PaUtilAllocationGroupLink *current = group->allocations;
+    struct PaUtilAllocationGroupLink *previous = 0;
+
+    if( buffer == 0 )
+        return;
+
+    /* find the right link and remove it */
+    while( current )
+    {
+        if( current->buffer == buffer )
+        {
+            if( previous )
+            {
+                previous->next = current->next;
+            }
+            else
+            {
+                group->allocations = current->next;
+            }
+
+            current->buffer = 0;
+            current->next = group->spareLinks;
+            group->spareLinks = current;
+
+            break;
+        }
+
+        previous = current;
+        current = current->next;
+    }
+
+    PaUtil_FreeMemory( buffer ); /* free the memory whether we found it in the list or not */
+}
+
+
+void PaUtil_FreeAllAllocations( PaUtilAllocationGroup* group )
+{
+    struct PaUtilAllocationGroupLink *current = group->allocations;
+    struct PaUtilAllocationGroupLink *previous = 0;
+
+    /* free all buffers in the allocations list */
+    while( current )
+    {
+        PaUtil_FreeMemory( current->buffer );
+        current->buffer = 0;
+
+        previous = current;
+        current = current->next;
+    }
+
+    /* link the former allocations list onto the front of the spareLinks list */
+    if( previous )
+    {
+        previous->next = group->spareLinks;
+        group->spareLinks = group->allocations;
+        group->allocations = 0;
+    }
+}