go-ethereum/fdtrack/fdusage_darwin.go

73 lines
2.0 KiB
Go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build darwin
package fdtrack
import (
"os"
"syscall"
"unsafe"
)
// #cgo CFLAGS: -lproc
// #include <libproc.h>
// #include <stdlib.h>
import "C"
func fdlimit() int {
var nofile syscall.Rlimit
if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &nofile); err != nil {
return 0
}
return int(nofile.Cur)
}
func fdusage() (int, error) {
pid := C.int(os.Getpid())
// Query for a rough estimate on the amout of data that
// proc_pidinfo will return.
rlen, err := C.proc_pidinfo(pid, C.PROC_PIDLISTFDS, 0, nil, 0)
if rlen <= 0 {
return 0, err
}
// Load the list of file descriptors. We don't actually care about
// the content, only about the size. Since the number of fds can
// change while we're reading them, the loop enlarges the buffer
// until proc_pidinfo says the result fitted.
var buf unsafe.Pointer
defer func() {
if buf != nil {
C.free(buf)
}
}()
for buflen := rlen; ; buflen *= 2 {
buf, err = C.reallocf(buf, C.size_t(buflen))
if buf == nil {
return 0, err
}
rlen, err = C.proc_pidinfo(pid, C.PROC_PIDLISTFDS, 0, buf, buflen)
if rlen <= 0 {
return 0, err
} else if rlen == buflen {
continue
}
return int(rlen / C.PROC_PIDLISTFD_SIZE), nil
}
panic("unreachable")
}