This class implements the bslma::Allocator protocol to provide an allocator that manages pooled memory blocks of some uniform size, specified either at construction, or at the first invocation of the allocate method. This allocator maintains an internal linked list of free memory blocks, and dispenses one block for each allocate method invocation. When a memory block is deallocated, it is returned to the free list for potential reuse.
Declared in <bdlma_concurrentpoolallocator.h>
class ConcurrentPoolAllocator
: public bslma::AllocatorThis class guarantees thread-safety while allocating or releasing memory.
| Name | Description |
|---|---|
bslma::Allocator | This protocol class provides a pure abstract interface and contract for clients and suppliers of raw memory. If the requested memory cannot be returned, the contract requires that an std::bad_alloc exception be thrown. Note that memory is guaranteed to be sufficiently aligned for any object of the requested size on the current platform, which may be less than the maximal alignment guarantee afforded by global operator new. |
| Name | Description |
|---|---|
size_type | This typedef is an alias for the block size type. |
| Name | Description |
|---|---|
ConcurrentPoolAllocator [constructor] | Constructors |
~ConcurrentPoolAllocator [destructor] [virtual] | Destroy this pool allocator. |
operator= | |
allocate | Return a newly allocated block of memory of (at least) the specified positive size (in bytes), and having alignment conforming to the platform requirement for any object having size bytes. If size is 0, a null pointer is returned with no effect. If the block size is not supplied at construction, then the size specified in the first call to this method fixes the block size. If size is greater than the value returned by blockSize, the allocation request will be satisfied directly by the external allocator supplied at construction (or the default allocator, if no allocator was supplied). |
blockSize | Return the size (in bytes) of the memory blocks allocated from this allocator. Note that all blocks dispensed by this allocator have the same size. |
deallocate | Return the memory at the specified address back to this allocator. If address is 0, this method has no effect. The behavior is undefined unless address was allocated using this allocator and has not already been deallocated. |
deleteObject | deleteObject overloads |
deleteObjectRaw | deleteObjectRaw overloads |
is_equal | |
release | Relinquish all memory currently allocated through this pool allocator. |
reserveCapacity | Reserve memory from this pool allocator to satisfy memory requests for at least the specified numObjects before the pool replenishes. The behavior is undefined unless 0 <= numObjects. Note that this operation has no effect unless block size was supplied at construction, or allocate was invoked. |
| Name | Description |
|---|---|
throwBadAlloc | Throw std::bad_alloc if exceptions are enabled or abort the program otherwise. Derived classes and helper functions will typically call this function when they are unable to satisfy an allocation request. This function never returns. |
| Name | Description |
|---|---|
do_allocate [virtual] | Return a newly allocated block of memory of (at least) the specified positive bytes and having at least the specified alignment. Unless overriden in a derived class, the return value is this->allocate(bytes). If this allocator cannot return the requested number of bytes or cannot satisfy the alignment request, then it will throw a std::bad_alloc exception in an exception-enabled build, or else will abort the program in a non-exception build. Unless overriden in a derived class, this function will forward the allocation request to the allocate virtual function, padding bytes and adjusting the return value as necessary to ensure sufficient alignment. Note that if bytes is 0, the same non-null value will be returned every time. |
do_deallocate [virtual] | Return the memory block at the specified p address, having the specified bytes and specified alignment, back to this allocator. Unless overriden in a derived class, this function will forward the deallocation request to the deallocate virtual function, padding bytes and adjusting p as necessary to account for alignment values other than the natural alignment for an object of size bytes. The behavior is undefined unless address is a block allocated from this allocator object using the same bytes and alignment and not already deallocated. |
do_is_equal [virtual] | Return true if this allocator is equal to the specified other allocator, meaning (at least) that a memory block allocated by one can be deallocated by the other; otherwise return false. Unless overriden, this method returns this == &other. |