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Diffstat (limited to 'vendor/src/github.com/coreos/go-systemd/journal/send.go')
-rw-r--r--vendor/src/github.com/coreos/go-systemd/journal/send.go168
1 files changed, 168 insertions, 0 deletions
diff --git a/vendor/src/github.com/coreos/go-systemd/journal/send.go b/vendor/src/github.com/coreos/go-systemd/journal/send.go
new file mode 100644
index 0000000000..a29bcbf0fa
--- /dev/null
+++ b/vendor/src/github.com/coreos/go-systemd/journal/send.go
@@ -0,0 +1,168 @@
+/*
+Copyright 2013 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 systemd journal
+package journal
+
+import (
+ "bytes"
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "net"
+ "os"
+ "strconv"
+ "strings"
+ "syscall"
+)
+
+// Priority of a journal message
+type Priority int
+
+const (
+ PriEmerg Priority = iota
+ PriAlert
+ PriCrit
+ PriErr
+ PriWarning
+ PriNotice
+ PriInfo
+ PriDebug
+)
+
+var conn net.Conn
+
+func init() {
+ var err error
+ conn, err = net.Dial("unixgram", "/run/systemd/journal/socket")
+ if err != nil {
+ conn = nil
+ }
+}
+
+// Enabled returns true iff the systemd journal is available for logging
+func Enabled() bool {
+ return conn != nil
+}
+
+// Send a message to the 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 {
+ if conn == nil {
+ return journalError("could not connect to journald socket")
+ }
+
+ 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 := io.Copy(conn, data)
+ if err != nil && isSocketSpaceError(err) {
+ file, err := tempFd()
+ if err != nil {
+ return journalError(err.Error())
+ }
+ _, err = io.Copy(file, data)
+ if err != nil {
+ return journalError(err.Error())
+ }
+
+ rights := syscall.UnixRights(int(file.Fd()))
+
+ /* this connection should always be a UnixConn, but better safe than sorry */
+ unixConn, ok := conn.(*net.UnixConn)
+ if !ok {
+ return journalError("can't send file through non-Unix connection")
+ }
+ unixConn.WriteMsgUnix([]byte{}, rights, nil)
+ } else if err != nil {
+ return journalError(err.Error())
+ }
+ return nil
+}
+
+func appendVariable(w io.Writer, name, value string) {
+ if !validVarName(name) {
+ journalError("variable name contains invalid character, ignoring")
+ }
+ 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.Fprintln(w, "%s=%s", name, value)
+ }
+}
+
+func validVarName(name string) bool {
+ /* The variable name must be in uppercase and consist only of characters,
+ * numbers and underscores, and may not begin with an underscore. (from the docs)
+ */
+
+ valid := name[0] != '_'
+ for _, c := range name {
+ valid = valid && ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_'
+ }
+ return valid
+}
+
+func isSocketSpaceError(err error) bool {
+ opErr, ok := err.(*net.OpError)
+ if !ok {
+ return false
+ }
+
+ sysErr, ok := opErr.Err.(syscall.Errno)
+ if !ok {
+ return false
+ }
+
+ return sysErr == syscall.EMSGSIZE || sysErr == syscall.ENOBUFS
+}
+
+func tempFd() (*os.File, error) {
+ file, err := ioutil.TempFile("/dev/shm/", "journal.XXXXX")
+ if err != nil {
+ return nil, err
+ }
+ syscall.Unlink(file.Name())
+ if err != nil {
+ return nil, err
+ }
+ return file, nil
+}
+
+func journalError(s string) error {
+ s = "journal error: " + s
+ fmt.Fprintln(os.Stderr, s)
+ return errors.New(s)
+}