mergerfs/src/fuse_readdir_factory.cpp
2023-10-14 00:58:10 -05:00

115 lines
2.8 KiB
C++

/*
ISC License
Copyright (c) 2023, Antonio SJ Musumeci <trapexit@spawn.link>
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "fuse_readdir_factory.hpp"
#include "fuse_readdir_cor.hpp"
#include "fuse_readdir_cosr.hpp"
#include "fuse_readdir_seq.hpp"
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <set>
#define DEFAULT_MAX_QUEUE_DEPTH 3
namespace l
{
static
void
read_cfg(std::string const str_,
std::string &type_,
unsigned &concurrency_,
unsigned &max_queue_depth_)
{
char type[16];
int concurrency;
int max_queue_depth;
concurrency = 0;
max_queue_depth = 0;
std::sscanf(str_.c_str(),
"%15[a-z]:%d:%d",
type,
&concurrency,
&max_queue_depth);
if(concurrency == 0)
concurrency = std::thread::hardware_concurrency();
else if(concurrency < 0)
concurrency = (std::thread::hardware_concurrency() / std::abs(concurrency));
if(concurrency == 0)
concurrency = 1;
if(max_queue_depth == 0)
max_queue_depth = DEFAULT_MAX_QUEUE_DEPTH;
max_queue_depth *= concurrency;
type_ = type;
concurrency_ = concurrency;
max_queue_depth_ = max_queue_depth;
}
}
bool
FUSE::ReadDirFactory::valid(std::string const str_)
{
unsigned concurrency;
unsigned max_queue_depth;
std::string type;
static const std::set<std::string> types =
{
"seq", "cosr", "cor"
};
l::read_cfg(str_,type,concurrency,max_queue_depth);
if(types.find(type) == types.end())
return false;
if(concurrency <= 0)
return false;
return true;
}
std::shared_ptr<FUSE::ReadDirBase>
FUSE::ReadDirFactory::make(std::string const str_)
{
unsigned concurrency;
unsigned max_queue_depth;
std::string type;
if(!valid(str_))
return {};
l::read_cfg(str_,type,concurrency,max_queue_depth);
if(type == "seq")
return std::make_shared<FUSE::ReadDirSeq>();
if(type == "cosr")
return std::make_shared<FUSE::ReadDirCOSR>(concurrency,max_queue_depth);
if(type == "cor")
return std::make_shared<FUSE::ReadDirCOR>(concurrency,max_queue_depth);
return {};
}