int main ()
{
//We will create a buffer of 1000 bytes to store a list
managed_heap_memory heap_memory(1000);
MyList * mylist = heap_memory.construct<MyList>("MyList")
(heap_memory.get_segment_manager());
//Obtain handle, that identifies the list in the buffer
managed_heap_memory::handle_t list_handle = heap_memory.get_handle_from_address(mylist);
//Fill list until there is no more memory in the buffer
try{
while(1) {
mylist->insert(mylist->begin(), 0);
}
}
catch(const bad_alloc &){
//memory is full
}
//Let's obtain the size of the list
MyList::size_type old_size = mylist->size();
//<-
(void)old_size;
//->
//To make the list bigger, let's increase the heap buffer
//in 1000 bytes more.
heap_memory.grow(1000);
//If memory has been reallocated, the old pointer is invalid, so
//use previously obtained handle to find the new pointer.
mylist = static_cast<MyList *>
(heap_memory.get_address_from_handle(list_handle));
//Fill list until there is no more memory in the buffer
try{
while(1) {
mylist->insert(mylist->begin(), 0);
}
}
catch(const bad_alloc &){
//memory is full
}
//Let's obtain the new size of the list
MyList::size_type new_size = mylist->size();
//<-
(void)new_size;
//->
assert(new_size > old_size);
//Destroy list
heap_memory.destroy_ptr(mylist);
return 0;
}
int main ()
{
const char *FileName = "file_mapping";
const std::size_t FileSize = 1000;
file_mapping::remove(FileName);
try{
std::size_t old_size = 0;
managed_mapped_file::handle_t list_handle;
{
managed_mapped_file mfile_memory(create_only, FileName, FileSize);
MyList *mylist = mfile_memory.construct<MyList>("MyList")
(mfile_memory.get_segment_manager());
//Obtain handle, that identifies the list in the buffer
list_handle = mfile_memory.get_handle_from_address(mylist);
//Fill list until there is no more room in the file
try{
while(1) {
mylist->insert(mylist->begin(), 0);
}
}
catch(const bad_alloc &){
//mapped file is full
}
//Let's obtain the size of the list
old_size = mylist->size();
}
//To make the list bigger, let's increase the mapped file
//in FileSize bytes more.
managed_mapped_file::grow(FileName, FileSize*2);
{
managed_mapped_file mfile_memory(open_only, FileName);
//If mapping address has changed, the old pointer is invalid,
//so use previously obtained handle to find the new pointer.
MyList *mylist = static_cast<MyList *>
(mfile_memory.get_address_from_handle(list_handle));
//Fill list until there is no more room in the file
try{
while(1) {
mylist->insert(mylist->begin(), 0);
}
}
catch(const bad_alloc &){
//mapped file is full
}
//Let's obtain the new size of the list
std::size_t new_size = mylist->size();
assert(new_size > old_size);
//Destroy list
mfile_memory.destroy_ptr(mylist);
}
}
catch(...){
file_mapping::remove(FileName);
throw;
}
file_mapping::remove(FileName);
return 0;
}