FreeRDP/winpr/libwinpr/utils/collections/BufferPool.c
2022-10-11 13:28:30 +02:00

558 lines
10 KiB
C

/**
* WinPR: Windows Portable Runtime
* Buffer Pool
*
* Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <winpr/config.h>
#include <winpr/crt.h>
#include <winpr/collections.h>
typedef struct
{
SSIZE_T size;
void* buffer;
} wBufferPoolItem;
struct s_wBufferPool
{
SSIZE_T fixedSize;
DWORD alignment;
BOOL synchronized;
CRITICAL_SECTION lock;
SSIZE_T size;
SSIZE_T capacity;
void** array;
SSIZE_T aSize;
SSIZE_T aCapacity;
wBufferPoolItem* aArray;
SSIZE_T uSize;
SSIZE_T uCapacity;
wBufferPoolItem* uArray;
};
static BOOL BufferPool_Lock(wBufferPool* pool)
{
if (!pool)
return FALSE;
if (pool->synchronized)
EnterCriticalSection(&pool->lock);
return TRUE;
}
static BOOL BufferPool_Unlock(wBufferPool* pool)
{
if (!pool)
return FALSE;
if (pool->synchronized)
LeaveCriticalSection(&pool->lock);
return TRUE;
}
/**
* C equivalent of the C# BufferManager Class:
* http://msdn.microsoft.com/en-us/library/ms405814.aspx
*/
/**
* Methods
*/
static BOOL BufferPool_ShiftAvailable(wBufferPool* pool, size_t index, int count)
{
if (count > 0)
{
if (pool->aSize + count > pool->aCapacity)
{
wBufferPoolItem* newArray;
SSIZE_T newCapacity = pool->aCapacity * 2;
if (pool->alignment > 0)
newArray = (wBufferPoolItem*)winpr_aligned_realloc(
pool->aArray, sizeof(wBufferPoolItem) * newCapacity, pool->alignment);
else
newArray =
(wBufferPoolItem*)realloc(pool->aArray, sizeof(wBufferPoolItem) * newCapacity);
if (!newArray)
return FALSE;
pool->aArray = newArray;
pool->aCapacity = newCapacity;
}
MoveMemory(&pool->aArray[index + count], &pool->aArray[index],
(pool->aSize - index) * sizeof(wBufferPoolItem));
pool->aSize += count;
}
else if (count < 0)
{
MoveMemory(&pool->aArray[index], &pool->aArray[index - count],
(pool->aSize - index) * sizeof(wBufferPoolItem));
pool->aSize += count;
}
return TRUE;
}
static BOOL BufferPool_ShiftUsed(wBufferPool* pool, SSIZE_T index, SSIZE_T count)
{
if (count > 0)
{
if (pool->uSize + count > pool->uCapacity)
{
SSIZE_T newUCapacity = pool->uCapacity * 2;
wBufferPoolItem* newUArray;
if (pool->alignment > 0)
newUArray = (wBufferPoolItem*)winpr_aligned_realloc(
pool->uArray, sizeof(wBufferPoolItem) * newUCapacity, pool->alignment);
else
newUArray =
(wBufferPoolItem*)realloc(pool->uArray, sizeof(wBufferPoolItem) * newUCapacity);
if (!newUArray)
return FALSE;
pool->uCapacity = newUCapacity;
pool->uArray = newUArray;
}
MoveMemory(&pool->uArray[index + count], &pool->uArray[index],
(pool->uSize - index) * sizeof(wBufferPoolItem));
pool->uSize += count;
}
else if (count < 0)
{
MoveMemory(&pool->uArray[index], &pool->uArray[index - count],
(pool->uSize - index) * sizeof(wBufferPoolItem));
pool->uSize += count;
}
return TRUE;
}
/**
* Get the buffer pool size
*/
SSIZE_T BufferPool_GetPoolSize(wBufferPool* pool)
{
SSIZE_T size;
BufferPool_Lock(pool);
if (pool->fixedSize)
{
/* fixed size buffers */
size = pool->size;
}
else
{
/* variable size buffers */
size = pool->uSize;
}
BufferPool_Unlock(pool);
return size;
}
/**
* Get the size of a pooled buffer
*/
SSIZE_T BufferPool_GetBufferSize(wBufferPool* pool, const void* buffer)
{
SSIZE_T size = 0;
SSIZE_T index = 0;
BOOL found = FALSE;
BufferPool_Lock(pool);
if (pool->fixedSize)
{
/* fixed size buffers */
size = pool->fixedSize;
found = TRUE;
}
else
{
/* variable size buffers */
for (index = 0; index < pool->uSize; index++)
{
if (pool->uArray[index].buffer == buffer)
{
size = pool->uArray[index].size;
found = TRUE;
break;
}
}
}
BufferPool_Unlock(pool);
return (found) ? size : -1;
}
/**
* Gets a buffer of at least the specified size from the pool.
*/
void* BufferPool_Take(wBufferPool* pool, SSIZE_T size)
{
SSIZE_T index;
SSIZE_T maxSize;
SSIZE_T maxIndex;
SSIZE_T foundIndex = -1;
BOOL found = FALSE;
void* buffer = NULL;
BufferPool_Lock(pool);
if (pool->fixedSize)
{
/* fixed size buffers */
if (pool->size > 0)
buffer = pool->array[--(pool->size)];
if (!buffer)
{
if (pool->alignment)
buffer = winpr_aligned_malloc(pool->fixedSize, pool->alignment);
else
buffer = malloc(pool->fixedSize);
}
if (!buffer)
goto out_error;
}
else
{
/* variable size buffers */
maxSize = 0;
maxIndex = 0;
if (size < 1)
size = pool->fixedSize;
for (index = 0; index < pool->aSize; index++)
{
if (pool->aArray[index].size > maxSize)
{
maxIndex = index;
maxSize = pool->aArray[index].size;
}
if (pool->aArray[index].size >= size)
{
foundIndex = index;
found = TRUE;
break;
}
}
if (!found && maxSize)
{
foundIndex = maxIndex;
found = TRUE;
}
if (!found)
{
if (!size)
buffer = NULL;
else
{
if (pool->alignment)
buffer = winpr_aligned_malloc(size, pool->alignment);
else
buffer = malloc(size);
if (!buffer)
goto out_error;
}
}
else
{
buffer = pool->aArray[foundIndex].buffer;
if (maxSize < size)
{
void* newBuffer;
if (pool->alignment)
newBuffer = winpr_aligned_realloc(buffer, size, pool->alignment);
else
newBuffer = realloc(buffer, size);
if (!newBuffer)
goto out_error_no_free;
buffer = newBuffer;
}
if (!BufferPool_ShiftAvailable(pool, foundIndex, -1))
goto out_error;
}
if (!buffer)
goto out_error;
if (pool->uSize + 1 > pool->uCapacity)
{
size_t newUCapacity = pool->uCapacity * 2;
wBufferPoolItem* newUArray =
(wBufferPoolItem*)realloc(pool->uArray, sizeof(wBufferPoolItem) * newUCapacity);
if (!newUArray)
goto out_error;
pool->uCapacity = newUCapacity;
pool->uArray = newUArray;
}
pool->uArray[pool->uSize].buffer = buffer;
pool->uArray[pool->uSize].size = size;
(pool->uSize)++;
}
BufferPool_Unlock(pool);
return buffer;
out_error:
if (pool->alignment)
winpr_aligned_free(buffer);
else
free(buffer);
out_error_no_free:
BufferPool_Unlock(pool);
return NULL;
}
/**
* Returns a buffer to the pool.
*/
BOOL BufferPool_Return(wBufferPool* pool, void* buffer)
{
BOOL rc = FALSE;
SSIZE_T size = 0;
SSIZE_T index = 0;
BOOL found = FALSE;
BufferPool_Lock(pool);
if (pool->fixedSize)
{
/* fixed size buffers */
if ((pool->size + 1) >= pool->capacity)
{
SSIZE_T newCapacity = pool->capacity * 2;
void** newArray = (void**)realloc(pool->array, sizeof(void*) * newCapacity);
if (!newArray)
goto out_error;
pool->capacity = newCapacity;
pool->array = newArray;
}
pool->array[(pool->size)++] = buffer;
}
else
{
/* variable size buffers */
for (index = 0; index < pool->uSize; index++)
{
if (pool->uArray[index].buffer == buffer)
{
found = TRUE;
break;
}
}
if (found)
{
size = pool->uArray[index].size;
if (!BufferPool_ShiftUsed(pool, index, -1))
goto out_error;
}
if (size)
{
if ((pool->aSize + 1) >= pool->aCapacity)
{
SSIZE_T newCapacity = pool->aCapacity * 2;
wBufferPoolItem* newArray =
(wBufferPoolItem*)realloc(pool->aArray, sizeof(wBufferPoolItem) * newCapacity);
if (!newArray)
goto out_error;
pool->aCapacity = newCapacity;
pool->aArray = newArray;
}
pool->aArray[pool->aSize].buffer = buffer;
pool->aArray[pool->aSize].size = size;
(pool->aSize)++;
}
}
rc = TRUE;
out_error:
BufferPool_Unlock(pool);
return rc;
}
/**
* Releases the buffers currently cached in the pool.
*/
void BufferPool_Clear(wBufferPool* pool)
{
BufferPool_Lock(pool);
if (pool->fixedSize)
{
/* fixed size buffers */
while (pool->size > 0)
{
(pool->size)--;
if (pool->alignment)
winpr_aligned_free(pool->array[pool->size]);
else
free(pool->array[pool->size]);
}
}
else
{
/* variable size buffers */
while (pool->aSize > 0)
{
(pool->aSize)--;
if (pool->alignment)
winpr_aligned_free(pool->aArray[pool->aSize].buffer);
else
free(pool->aArray[pool->aSize].buffer);
}
while (pool->uSize > 0)
{
(pool->uSize)--;
if (pool->alignment)
winpr_aligned_free(pool->uArray[pool->uSize].buffer);
else
free(pool->uArray[pool->uSize].buffer);
}
}
BufferPool_Unlock(pool);
}
/**
* Construction, Destruction
*/
wBufferPool* BufferPool_New(BOOL synchronized, SSIZE_T fixedSize, DWORD alignment)
{
wBufferPool* pool = NULL;
pool = (wBufferPool*)calloc(1, sizeof(wBufferPool));
if (pool)
{
pool->fixedSize = fixedSize;
if (pool->fixedSize < 0)
pool->fixedSize = 0;
pool->alignment = alignment;
pool->synchronized = synchronized;
if (pool->synchronized)
InitializeCriticalSectionAndSpinCount(&pool->lock, 4000);
if (pool->fixedSize)
{
/* fixed size buffers */
pool->size = 0;
pool->capacity = 32;
pool->array = (void**)calloc(pool->capacity, sizeof(void*));
if (!pool->array)
goto out_error;
}
else
{
/* variable size buffers */
pool->aSize = 0;
pool->aCapacity = 32;
pool->aArray = (wBufferPoolItem*)calloc(pool->aCapacity, sizeof(wBufferPoolItem));
if (!pool->aArray)
goto out_error;
pool->uSize = 0;
pool->uCapacity = 32;
pool->uArray = (wBufferPoolItem*)calloc(pool->uCapacity, sizeof(wBufferPoolItem));
if (!pool->uArray)
goto out_error;
}
}
return pool;
out_error:
BufferPool_Free(pool);
return NULL;
}
void BufferPool_Free(wBufferPool* pool)
{
if (pool)
{
BufferPool_Clear(pool);
if (pool->synchronized)
DeleteCriticalSection(&pool->lock);
if (pool->fixedSize)
{
/* fixed size buffers */
free(pool->array);
}
else
{
/* variable size buffers */
free(pool->aArray);
free(pool->uArray);
}
free(pool);
}
}