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Changes for Boost.1.39

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[SVN r51964]
This commit is contained in:
Ion Gaztañaga
2009-03-24 21:52:06 +00:00
parent 814c51a803
commit 3d0fcd68e3
274 changed files with 23335 additions and 20691 deletions
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65
example/doc_managed_aligned_allocation.cpp
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@@ -16,53 +16,52 @@ int main()
{
using namespace boost::interprocess;
//Remove shared memory on construction and destruction
struct shm_destroy
{
shm_destroy() { shared_memory_object::remove("MySharedMemory"); }
~shm_destroy(){ shared_memory_object::remove("MySharedMemory"); }
} remover;
//Managed memory segment that allocates portions of a shared memory
//segment with the default management algorithm
shared_memory_object::remove("MyManagedShm");
managed_shared_memory managed_shm(create_only, "MySharedMemory", 65536);
try{
managed_shared_memory managed_shm(create_only, "MyManagedShm", 65536);
const std::size_t Alignment = 128;
const std::size_t Alignment = 128;
//Allocate 100 bytes aligned to Alignment from segment, throwing version
void *ptr = managed_shm.allocate_aligned(100, Alignment);
//Allocate 100 bytes aligned to Alignment from segment, throwing version
void *ptr = managed_shm.allocate_aligned(100, Alignment);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Deallocate it
managed_shm.deallocate(ptr);
//Deallocate it
managed_shm.deallocate(ptr);
//Non throwing version
ptr = managed_shm.allocate_aligned(100, Alignment, std::nothrow);
//Non throwing version
ptr = managed_shm.allocate_aligned(100, Alignment, std::nothrow);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Deallocate it
managed_shm.deallocate(ptr);
//Deallocate it
managed_shm.deallocate(ptr);
//If we want to efficiently allocate aligned blocks of memory
//use managed_shared_memory::PayloadPerAllocation value
assert(Alignment > managed_shared_memory::PayloadPerAllocation);
//If we want to efficiently allocate aligned blocks of memory
//use managed_shared_memory::PayloadPerAllocation value
assert(Alignment > managed_shared_memory::PayloadPerAllocation);
//This allocation will maximize the size of the aligned memory
//and will increase the possibility of finding more aligned memory
ptr = managed_shm.allocate_aligned
(3*Alignment - managed_shared_memory::PayloadPerAllocation, Alignment);
//This allocation will maximize the size of the aligned memory
//and will increase the possibility of finding more aligned memory
ptr = managed_shm.allocate_aligned
(3*Alignment - managed_shared_memory::PayloadPerAllocation, Alignment);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Check alignment
assert((static_cast<char*>(ptr)-static_cast<char*>(0)) % Alignment == 0);
//Deallocate it
managed_shm.deallocate(ptr);
//Deallocate it
managed_shm.deallocate(ptr);
}
catch(...){
shared_memory_object::remove("MyManagedShm");
throw;
}
shared_memory_object::remove("MyManagedShm");
return 0;
}
//]