mirror of
https://github.com/trapexit/mergerfs.git
synced 2024-12-05 07:20:30 +08:00
210 lines
4.2 KiB
C++
210 lines
4.2 KiB
C++
/*
|
|
Copyright (c) 2016, 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 <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdlib.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "fs_attr.hpp"
|
|
#include "fs_fallocate.hpp"
|
|
#include "fs_sendfile.hpp"
|
|
#include "fs_xattr.hpp"
|
|
|
|
using std::string;
|
|
using std::vector;
|
|
|
|
namespace fs
|
|
{
|
|
int
|
|
writen(const int fd,
|
|
const char *buf,
|
|
const size_t count)
|
|
{
|
|
size_t nleft;
|
|
ssize_t nwritten;
|
|
|
|
nleft = count;
|
|
while(nleft > 0)
|
|
{
|
|
nwritten = ::write(fd,buf,nleft);
|
|
if(nwritten == -1)
|
|
{
|
|
if(errno == EINTR)
|
|
continue;
|
|
return -1;
|
|
}
|
|
|
|
nleft -= nwritten;
|
|
buf += nwritten;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
static
|
|
int
|
|
copyfile_rw(const int fdin,
|
|
const int fdout,
|
|
const size_t count,
|
|
const size_t blocksize)
|
|
{
|
|
ssize_t nr;
|
|
ssize_t nw;
|
|
ssize_t bufsize;
|
|
size_t totalwritten;
|
|
vector<char> buf;
|
|
|
|
bufsize = (blocksize * 16);
|
|
buf.resize(bufsize);
|
|
|
|
::lseek(fdin,0,SEEK_SET);
|
|
|
|
totalwritten = 0;
|
|
while(totalwritten < count)
|
|
{
|
|
nr = ::read(fdin,&buf[0],bufsize);
|
|
if(nr == -1)
|
|
{
|
|
if(errno == EINTR)
|
|
continue;
|
|
return -1;
|
|
}
|
|
|
|
nw = writen(fdout,&buf[0],nr);
|
|
if(nw == -1)
|
|
return -1;
|
|
|
|
totalwritten += nw;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
static
|
|
int
|
|
copydata(const int fdin,
|
|
const int fdout,
|
|
const size_t count,
|
|
const size_t blocksize)
|
|
{
|
|
int rv;
|
|
|
|
::posix_fadvise(fdin,0,count,POSIX_FADV_WILLNEED);
|
|
::posix_fadvise(fdin,0,count,POSIX_FADV_SEQUENTIAL);
|
|
|
|
fs::fallocate(fdout,0,0,count);
|
|
|
|
rv = fs::sendfile(fdin,fdout,count);
|
|
if((rv == -1) && ((errno == EINVAL) || (errno == ENOSYS)))
|
|
return fs::copyfile_rw(fdin,fdout,count,blocksize);
|
|
|
|
return rv;
|
|
}
|
|
|
|
static
|
|
bool
|
|
ignorable_error(const int err)
|
|
{
|
|
switch(err)
|
|
{
|
|
case ENOTTY:
|
|
case ENOTSUP:
|
|
#if ENOTSUP != EOPNOTSUPP
|
|
case EOPNOTSUPP:
|
|
#endif
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
int
|
|
clonefile(const int fdin,
|
|
const int fdout)
|
|
{
|
|
int rv;
|
|
struct stat stin;
|
|
|
|
rv = ::fstat(fdin,&stin);
|
|
if(rv == -1)
|
|
return -1;
|
|
|
|
rv = copydata(fdin,fdout,stin.st_size,stin.st_blksize);
|
|
if(rv == -1)
|
|
return -1;
|
|
|
|
rv = fs::attr::copy(fdin,fdout);
|
|
if(rv == -1 && !ignorable_error(errno))
|
|
return -1;
|
|
|
|
rv = fs::xattr::copy(fdin,fdout);
|
|
if(rv == -1 && !ignorable_error(errno))
|
|
return -1;
|
|
|
|
rv = ::fchown(fdout,stin.st_uid,stin.st_gid);
|
|
if(rv == -1)
|
|
return -1;
|
|
|
|
rv = ::fchmod(fdout,stin.st_mode);
|
|
if(rv == -1)
|
|
return -1;
|
|
|
|
struct timespec times[2];
|
|
times[0] = stin.st_atim;
|
|
times[1] = stin.st_mtim;
|
|
rv = ::futimens(fdout,times);
|
|
if(rv == -1)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
clonefile(const string &in,
|
|
const string &out)
|
|
{
|
|
int rv;
|
|
int fdin;
|
|
int fdout;
|
|
int error;
|
|
|
|
fdin = ::open(in.c_str(),O_RDONLY|O_NOFOLLOW);
|
|
if(fdin == -1)
|
|
return -1;
|
|
|
|
const int flags = O_CREAT|O_LARGEFILE|O_NOATIME|O_NOFOLLOW|O_TRUNC|O_WRONLY;
|
|
const int mode = S_IWUSR;
|
|
fdout = ::open(out.c_str(),flags,mode);
|
|
if(fdout == -1)
|
|
return -1;
|
|
|
|
rv = fs::clonefile(fdin,fdout);
|
|
error = errno;
|
|
|
|
::close(fdin);
|
|
::close(fdout);
|
|
|
|
errno = error;
|
|
return rv;
|
|
}
|
|
}
|