BDE 4.14.0 Production release
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#include <bdlma_sequentialpool.h>
This class implements a fast memory pool that efficiently dispenses heterogeneous blocks of memory (of varying, user-specified sizes) from a sequence of dynamically-allocated internal buffers. Memory for the internal buffers is supplied by an (optional) allocator supplied at construction; if no allocator is supplied, the currently installed default allocator is used. If an allocation exceeds the remaining free memory space in the current buffer, the pool replenishes its internal buffer with new memory to satisfy the request. This class is exception neutral: If memory cannot be allocated, the behavior is defined by the (optional) allocator specified at construction.
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explicit |
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explicit |
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explicit |
bdlma::SequentialPool::SequentialPool | ( | bsls::BlockGrowth::Strategy | growthStrategy, |
bsls::Alignment::Strategy | alignmentStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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Create a sequential pool for allocating memory blocks from a sequence of dynamically-allocated buffers. Optionally specify a basicAllocator
used to supply memory for the dynamically-allocated buffers. If basicAllocator
is 0, the currently installed default allocator is used. Optionally specify a growthStrategy
used to control buffer growth. If no growthStrategy
is specified, geometric growth is used. Optionally specify an alignmentStrategy
used to control alignment of allocated memory blocks. If no alignmentStrategy
is specified, natural alignment is used. An implementation-defined value is used as the initial size of the internal buffer. Note that no limit is imposed on the size of the internal buffers when geometric growth is used. Also note that when constant growth is used, the size of the internal buffers will always be the same as the implementation-defined value.
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explicit |
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bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::BlockGrowth::Strategy | growthStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Alignment::Strategy | alignmentStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::BlockGrowth::Strategy | growthStrategy, | ||
bsls::Alignment::Strategy | alignmentStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
Create a sequential pool for allocating memory blocks from a sequence of dynamically-allocated buffers, of which the initial buffer has the specified initialSize
(in bytes). Optionally specify a basicAllocator
used to supply memory for the dynamically-allocated buffers. If basicAllocator
is 0, the currently installed default allocator is used. Optionally specify a growthStrategy
used to control buffer growth. If no growthStrategy
is specified, geometric growth is used. Optionally specify an alignmentStrategy
used to control alignment of allocated memory blocks. If no alignmentStrategy
is specified, natural alignment is used. By specifying an initialSize
, the construction of a sequential pool will incur a memory allocation. The behavior is undefined unless 0 < initialSize
. Note that no limit is imposed on the size of the internal buffers when geometric growth is used. Also note that when constant growth is used, the size of the internal buffers will always be the same as initialSize
. Also note that SequentialPool(int initialSize)
is provided to avoid ambiguous definitions.
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Types::size_type | maxBufferSize, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Types::size_type | maxBufferSize, | ||
bsls::BlockGrowth::Strategy | growthStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Types::size_type | maxBufferSize, | ||
bsls::Alignment::Strategy | alignmentStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Types::size_type | maxBufferSize, | ||
bsls::BlockGrowth::Strategy | growthStrategy, | ||
bsls::Alignment::Strategy | alignmentStrategy, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
Create a sequential pool for allocating memory blocks from a sequence of dynamically-allocated buffers, of which the initial buffer has the specified initialSize
(in bytes), and the internal buffer growth is limited to the specified maxBufferSize
. Optionally specify a basicAllocator
used to supply memory for the dynamically-allocated buffers. If basicAllocator
is 0, the currently installed default allocator is used. Optionally specify a growthStrategy
used to control buffer growth. If no growthStrategy
is specified, geometric growth is used. Optionally specify an alignmentStrategy
used to control alignment of allocated memory blocks. If no alignmentStrategy
is specified, natural alignment is used. The behavior is undefined unless 0 < initialSize
and initialSize <= maxBufferSize
. Note that when constant growth is used, the size of the internal buffers will always be the same as initialSize
.
bdlma::SequentialPool::SequentialPool | ( | bsls::Types::size_type | initialSize, |
bsls::Types::size_type | maxBufferSize, | ||
bsls::BlockGrowth::Strategy | growthStrategy, | ||
bsls::Alignment::Strategy | alignmentStrategy, | ||
bool | allocateInitialBuffer, | ||
bslma::Allocator * | basicAllocator = 0 |
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) |
Create a sequential pool for allocating memory blocks from a sequence of dynamically-allocated buffers, of which the initial buffer has the specified initialSize
(in bytes), the internal buffer growth is limited to the specified maxBufferSize
, the specified growthStrategy
is used to control buffer growth, and the specified alignmentStrategy
is used to control alignment of allocated memory blocks. Allocate the initial buffer only if the specified allocateInitialBuffer
is true
. Optionally specify a basicAllocator
used to supply memory for the dynamically-allocated buffers. If basicAllocator
is 0, the currently installed default allocator is used. The behavior is undefined unless 0 < initialSize
and initialSize <= maxBufferSize
. Note that when constant growth is used, the size of the internal buffers will always be the same as initialSize
.
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inline |
Destroy this sequential pool. All memory allocated by this pool is released.
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inline |
Return the address of a contiguous block of memory of the specified size
(in bytes) according to the alignment strategy specified at construction. If size
is 0, no memory is allocated and 0 is returned. If the allocation request exceeds the remaining free memory space in the current internal buffer, use the allocator supplied at construction to allocate a new internal buffer, then allocate memory from the new buffer.
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inline |
Return the address of a contiguous block of memory of at least the specified *size
(in bytes), and load the actual amount of memory allocated in *size
. If *size
is 0, return 0 with no effect. If the allocation request exceeds the remaining free memory space in the current internal buffer, use the allocator supplied at construction to allocate a new internal buffer, then allocate memory from the new buffer.
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Return the allocator used by this object to allocate memory. Note that this allocator can not be used to deallocate memory allocated through this pool.
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Destroy the specified object
. Note that this method has the same effect as the deleteObjectRaw
method (since no deallocation is involved), and exists for consistency across pools.
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Destroy the specified object
. Note that memory associated with object
is not deallocated because there is no deallocate
method in SequentialPool
.
void bdlma::SequentialPool::release | ( | ) |
Release all memory allocated through this pool and return to the underlying allocator all memory. The pool is reset to its default-constructed state, retaining the alignment and growth strategies, and the initial and maximum buffer sizes in effect following construction. The effect of subsequently - to this invocation of release
- using a pointer obtained from this object prior to this call to release
is undefined.
void bdlma::SequentialPool::reserveCapacity | ( | bsls::Types::size_type | numBytes | ) |
Reserve sufficient memory to satisfy allocation requests for at least the specified numBytes
without replenishment (i.e., without dynamic allocation). If numBytes
is 0, no memory is reserved. Note that, when the numBytes
is distributed over multiple allocate
requests - due to alignment effects - it is possible that not all numBytes
of memory will be used for allocation before triggering dynamic allocation.
void bdlma::SequentialPool::rewind | ( | ) |
Release all memory allocated through this pool and return to the underlying allocator only memory that was allocated outside of the typical internal buffer growth of this pool (i.e., large blocks). All retained memory will be used to satisfy subsequent allocations. The effect of subsequently - to this invocation of rewind
- using a pointer obtained from this object prior to this call to rewind
is undefined.
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inline |
Reduce the amount of memory allocated at the specified address
of the specified originalSize
(in bytes) to the specified newSize
. Return newSize
after truncating, or originalSize
if the memory block at address
cannot be truncated. This method can only truncate
the memory block returned by the most recent allocate
request from this memory pool, and otherwise has no effect. The behavior is undefined unless the memory block at address
was originally allocated by this memory pool, the size of the memory block at address
is originalSize
, newSize <= originalSize
, and release
was not called after allocating the memory block at address
.