diff options
Diffstat (limited to 'vendor/gopkg.in/fsnotify.v1/inotify_poller.go')
-rw-r--r-- | vendor/gopkg.in/fsnotify.v1/inotify_poller.go | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/vendor/gopkg.in/fsnotify.v1/inotify_poller.go b/vendor/gopkg.in/fsnotify.v1/inotify_poller.go deleted file mode 100644 index cc7db4b22..000000000 --- a/vendor/gopkg.in/fsnotify.v1/inotify_poller.go +++ /dev/null @@ -1,187 +0,0 @@ -// Copyright 2015 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// +build linux - -package fsnotify - -import ( - "errors" - - "golang.org/x/sys/unix" -) - -type fdPoller struct { - fd int // File descriptor (as returned by the inotify_init() syscall) - epfd int // Epoll file descriptor - pipe [2]int // Pipe for waking up -} - -func emptyPoller(fd int) *fdPoller { - poller := new(fdPoller) - poller.fd = fd - poller.epfd = -1 - poller.pipe[0] = -1 - poller.pipe[1] = -1 - return poller -} - -// Create a new inotify poller. -// This creates an inotify handler, and an epoll handler. -func newFdPoller(fd int) (*fdPoller, error) { - var errno error - poller := emptyPoller(fd) - defer func() { - if errno != nil { - poller.close() - } - }() - poller.fd = fd - - // Create epoll fd - poller.epfd, errno = unix.EpollCreate1(0) - if poller.epfd == -1 { - return nil, errno - } - // Create pipe; pipe[0] is the read end, pipe[1] the write end. - errno = unix.Pipe2(poller.pipe[:], unix.O_NONBLOCK) - if errno != nil { - return nil, errno - } - - // Register inotify fd with epoll - event := unix.EpollEvent{ - Fd: int32(poller.fd), - Events: unix.EPOLLIN, - } - errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.fd, &event) - if errno != nil { - return nil, errno - } - - // Register pipe fd with epoll - event = unix.EpollEvent{ - Fd: int32(poller.pipe[0]), - Events: unix.EPOLLIN, - } - errno = unix.EpollCtl(poller.epfd, unix.EPOLL_CTL_ADD, poller.pipe[0], &event) - if errno != nil { - return nil, errno - } - - return poller, nil -} - -// Wait using epoll. -// Returns true if something is ready to be read, -// false if there is not. -func (poller *fdPoller) wait() (bool, error) { - // 3 possible events per fd, and 2 fds, makes a maximum of 6 events. - // I don't know whether epoll_wait returns the number of events returned, - // or the total number of events ready. - // I decided to catch both by making the buffer one larger than the maximum. - events := make([]unix.EpollEvent, 7) - for { - n, errno := unix.EpollWait(poller.epfd, events, -1) - if n == -1 { - if errno == unix.EINTR { - continue - } - return false, errno - } - if n == 0 { - // If there are no events, try again. - continue - } - if n > 6 { - // This should never happen. More events were returned than should be possible. - return false, errors.New("epoll_wait returned more events than I know what to do with") - } - ready := events[:n] - epollhup := false - epollerr := false - epollin := false - for _, event := range ready { - if event.Fd == int32(poller.fd) { - if event.Events&unix.EPOLLHUP != 0 { - // This should not happen, but if it does, treat it as a wakeup. - epollhup = true - } - if event.Events&unix.EPOLLERR != 0 { - // If an error is waiting on the file descriptor, we should pretend - // something is ready to read, and let unix.Read pick up the error. - epollerr = true - } - if event.Events&unix.EPOLLIN != 0 { - // There is data to read. - epollin = true - } - } - if event.Fd == int32(poller.pipe[0]) { - if event.Events&unix.EPOLLHUP != 0 { - // Write pipe descriptor was closed, by us. This means we're closing down the - // watcher, and we should wake up. - } - if event.Events&unix.EPOLLERR != 0 { - // If an error is waiting on the pipe file descriptor. - // This is an absolute mystery, and should never ever happen. - return false, errors.New("Error on the pipe descriptor.") - } - if event.Events&unix.EPOLLIN != 0 { - // This is a regular wakeup, so we have to clear the buffer. - err := poller.clearWake() - if err != nil { - return false, err - } - } - } - } - - if epollhup || epollerr || epollin { - return true, nil - } - return false, nil - } -} - -// Close the write end of the poller. -func (poller *fdPoller) wake() error { - buf := make([]byte, 1) - n, errno := unix.Write(poller.pipe[1], buf) - if n == -1 { - if errno == unix.EAGAIN { - // Buffer is full, poller will wake. - return nil - } - return errno - } - return nil -} - -func (poller *fdPoller) clearWake() error { - // You have to be woken up a LOT in order to get to 100! - buf := make([]byte, 100) - n, errno := unix.Read(poller.pipe[0], buf) - if n == -1 { - if errno == unix.EAGAIN { - // Buffer is empty, someone else cleared our wake. - return nil - } - return errno - } - return nil -} - -// Close all poller file descriptors, but not the one passed to it. -func (poller *fdPoller) close() { - if poller.pipe[1] != -1 { - unix.Close(poller.pipe[1]) - } - if poller.pipe[0] != -1 { - unix.Close(poller.pipe[0]) - } - if poller.epfd != -1 { - unix.Close(poller.epfd) - } -} |