summaryrefslogtreecommitdiff
path: root/vendor/github.com/coreos/go-systemd/v22/journal/journal.go
diff options
context:
space:
mode:
authorValentin Rothberg <rothberg@redhat.com>2020-03-10 18:18:58 +0100
committerValentin Rothberg <rothberg@redhat.com>2020-03-10 18:34:55 +0100
commit450361fc640751c2a33210a02ceff0874c9f449b (patch)
treeeb0f958a0c46f769e344faf8732e5327b9458ca0 /vendor/github.com/coreos/go-systemd/v22/journal/journal.go
parent3d48940927b1133e2bfd1c3accba84345cc56ee6 (diff)
downloadpodman-450361fc640751c2a33210a02ceff0874c9f449b.tar.gz
podman-450361fc640751c2a33210a02ceff0874c9f449b.tar.bz2
podman-450361fc640751c2a33210a02ceff0874c9f449b.zip
update systemd & dbus dependencies
Update the outdated systemd and dbus dependencies which are now provided as go modules. This will further tighten our dependencies and releases and pave the way for the upcoming auto-update feature. Signed-off-by: Valentin Rothberg <rothberg@redhat.com>
Diffstat (limited to 'vendor/github.com/coreos/go-systemd/v22/journal/journal.go')
-rw-r--r--vendor/github.com/coreos/go-systemd/v22/journal/journal.go225
1 files changed, 225 insertions, 0 deletions
diff --git a/vendor/github.com/coreos/go-systemd/v22/journal/journal.go b/vendor/github.com/coreos/go-systemd/v22/journal/journal.go
new file mode 100644
index 000000000..a0f4837a0
--- /dev/null
+++ b/vendor/github.com/coreos/go-systemd/v22/journal/journal.go
@@ -0,0 +1,225 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package journal provides write bindings to the local systemd journal.
+// It is implemented in pure Go and connects to the journal directly over its
+// unix socket.
+//
+// To read from the journal, see the "sdjournal" package, which wraps the
+// sd-journal a C API.
+//
+// http://www.freedesktop.org/software/systemd/man/systemd-journald.service.html
+package journal
+
+import (
+ "bytes"
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "net"
+ "os"
+ "strconv"
+ "strings"
+ "sync"
+ "sync/atomic"
+ "syscall"
+ "unsafe"
+)
+
+// Priority of a journal message
+type Priority int
+
+const (
+ PriEmerg Priority = iota
+ PriAlert
+ PriCrit
+ PriErr
+ PriWarning
+ PriNotice
+ PriInfo
+ PriDebug
+)
+
+var (
+ // This can be overridden at build-time:
+ // https://github.com/golang/go/wiki/GcToolchainTricks#including-build-information-in-the-executable
+ journalSocket = "/run/systemd/journal/socket"
+
+ // unixConnPtr atomically holds the local unconnected Unix-domain socket.
+ // Concrete safe pointer type: *net.UnixConn
+ unixConnPtr unsafe.Pointer
+ // onceConn ensures that unixConnPtr is initialized exactly once.
+ onceConn sync.Once
+)
+
+func init() {
+ onceConn.Do(initConn)
+}
+
+// Enabled checks whether the local systemd journal is available for logging.
+func Enabled() bool {
+ onceConn.Do(initConn)
+
+ if (*net.UnixConn)(atomic.LoadPointer(&unixConnPtr)) == nil {
+ return false
+ }
+
+ if _, err := net.Dial("unixgram", journalSocket); err != nil {
+ return false
+ }
+
+ return true
+}
+
+// Send a message to the local systemd journal. vars is a map of journald
+// fields to values. Fields must be composed of uppercase letters, numbers,
+// and underscores, but must not start with an underscore. Within these
+// restrictions, any arbitrary field name may be used. Some names have special
+// significance: see the journalctl documentation
+// (http://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html)
+// for more details. vars may be nil.
+func Send(message string, priority Priority, vars map[string]string) error {
+ conn := (*net.UnixConn)(atomic.LoadPointer(&unixConnPtr))
+ if conn == nil {
+ return errors.New("could not initialize socket to journald")
+ }
+
+ socketAddr := &net.UnixAddr{
+ Name: journalSocket,
+ Net: "unixgram",
+ }
+
+ data := new(bytes.Buffer)
+ appendVariable(data, "PRIORITY", strconv.Itoa(int(priority)))
+ appendVariable(data, "MESSAGE", message)
+ for k, v := range vars {
+ appendVariable(data, k, v)
+ }
+
+ _, _, err := conn.WriteMsgUnix(data.Bytes(), nil, socketAddr)
+ if err == nil {
+ return nil
+ }
+ if !isSocketSpaceError(err) {
+ return err
+ }
+
+ // Large log entry, send it via tempfile and ancillary-fd.
+ file, err := tempFd()
+ if err != nil {
+ return err
+ }
+ defer file.Close()
+ _, err = io.Copy(file, data)
+ if err != nil {
+ return err
+ }
+ rights := syscall.UnixRights(int(file.Fd()))
+ _, _, err = conn.WriteMsgUnix([]byte{}, rights, socketAddr)
+ if err != nil {
+ return err
+ }
+
+ return nil
+}
+
+// Print prints a message to the local systemd journal using Send().
+func Print(priority Priority, format string, a ...interface{}) error {
+ return Send(fmt.Sprintf(format, a...), priority, nil)
+}
+
+func appendVariable(w io.Writer, name, value string) {
+ if err := validVarName(name); err != nil {
+ fmt.Fprintf(os.Stderr, "variable name %s contains invalid character, ignoring\n", name)
+ }
+ if strings.ContainsRune(value, '\n') {
+ /* When the value contains a newline, we write:
+ * - the variable name, followed by a newline
+ * - the size (in 64bit little endian format)
+ * - the data, followed by a newline
+ */
+ fmt.Fprintln(w, name)
+ binary.Write(w, binary.LittleEndian, uint64(len(value)))
+ fmt.Fprintln(w, value)
+ } else {
+ /* just write the variable and value all on one line */
+ fmt.Fprintf(w, "%s=%s\n", name, value)
+ }
+}
+
+// validVarName validates a variable name to make sure journald will accept it.
+// The variable name must be in uppercase and consist only of characters,
+// numbers and underscores, and may not begin with an underscore:
+// https://www.freedesktop.org/software/systemd/man/sd_journal_print.html
+func validVarName(name string) error {
+ if name == "" {
+ return errors.New("Empty variable name")
+ } else if name[0] == '_' {
+ return errors.New("Variable name begins with an underscore")
+ }
+
+ for _, c := range name {
+ if !(('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_') {
+ return errors.New("Variable name contains invalid characters")
+ }
+ }
+ return nil
+}
+
+// isSocketSpaceError checks whether the error is signaling
+// an "overlarge message" condition.
+func isSocketSpaceError(err error) bool {
+ opErr, ok := err.(*net.OpError)
+ if !ok || opErr == nil {
+ return false
+ }
+
+ sysErr, ok := opErr.Err.(*os.SyscallError)
+ if !ok || sysErr == nil {
+ return false
+ }
+
+ return sysErr.Err == syscall.EMSGSIZE || sysErr.Err == syscall.ENOBUFS
+}
+
+// tempFd creates a temporary, unlinked file under `/dev/shm`.
+func tempFd() (*os.File, error) {
+ file, err := ioutil.TempFile("/dev/shm/", "journal.XXXXX")
+ if err != nil {
+ return nil, err
+ }
+ err = syscall.Unlink(file.Name())
+ if err != nil {
+ return nil, err
+ }
+ return file, nil
+}
+
+// initConn initializes the global `unixConnPtr` socket.
+// It is meant to be called exactly once, at program startup.
+func initConn() {
+ autobind, err := net.ResolveUnixAddr("unixgram", "")
+ if err != nil {
+ return
+ }
+
+ sock, err := net.ListenUnixgram("unixgram", autobind)
+ if err != nil {
+ return
+ }
+
+ atomic.StorePointer(&unixConnPtr, unsafe.Pointer(sock))
+}