mirror of
https://github.com/scylladb/scylladb.git
synced 2026-04-27 20:05:10 +00:00
2f103a8558
Instead of having an std::vector<> manage the fragment array, allocate it at the end of the impl struct and manage it manually. The result isn't pretty but it does remove an allocation.
34 lines
1.0 KiB
C++
34 lines
1.0 KiB
C++
/*
|
|
* Copyright (C) 2014 Cloudius Systems, Ltd.
|
|
*/
|
|
|
|
#include "packet.hh"
|
|
|
|
namespace net {
|
|
|
|
constexpr size_t packet::internal_data_size;
|
|
constexpr size_t packet::default_nr_frags;
|
|
|
|
void packet::linearize(size_t at_frag, size_t desired_size) {
|
|
size_t nr_frags = 0;
|
|
size_t accum_size = 0;
|
|
while (accum_size < desired_size) {
|
|
accum_size += _impl->_frags[at_frag + nr_frags].size;
|
|
++nr_frags;
|
|
}
|
|
std::unique_ptr<char[]> new_frag{new char[accum_size]};
|
|
auto p = new_frag.get();
|
|
for (size_t i = 0; i < nr_frags; ++i) {
|
|
auto& f = _impl->_frags[at_frag + i];
|
|
p = std::copy(f.base, f.base + f.size, p);
|
|
}
|
|
// collapse nr_frags into one fragment
|
|
std::copy(_impl->_frags + at_frag + nr_frags, _impl->_frags + _impl->_nr_frags,
|
|
_impl->_frags + at_frag + 1);
|
|
_impl->_nr_frags -= nr_frags - 1;
|
|
_impl->_frags[at_frag] = fragment{new_frag.get(), accum_size};
|
|
_impl->_deleter = make_deleter(std::move(_impl->_deleter), [buf = std::move(new_frag)] {});
|
|
}
|
|
|
|
}
|