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-rw-r--r--vendor/github.com/coreos/go-systemd/v22/sdjournal/functions.go66
-rw-r--r--vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go1120
-rw-r--r--vendor/github.com/coreos/go-systemd/v22/sdjournal/read.go272
3 files changed, 1458 insertions, 0 deletions
diff --git a/vendor/github.com/coreos/go-systemd/v22/sdjournal/functions.go b/vendor/github.com/coreos/go-systemd/v22/sdjournal/functions.go
new file mode 100644
index 000000000..3cbd05658
--- /dev/null
+++ b/vendor/github.com/coreos/go-systemd/v22/sdjournal/functions.go
@@ -0,0 +1,66 @@
+// Copyright 2015 RedHat, Inc.
+// 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 sdjournal
+
+import (
+ "github.com/coreos/go-systemd/v22/internal/dlopen"
+ "sync"
+ "unsafe"
+)
+
+var (
+ // lazy initialized
+ libsystemdHandle *dlopen.LibHandle
+
+ libsystemdMutex = &sync.Mutex{}
+ libsystemdFunctions = map[string]unsafe.Pointer{}
+ libsystemdNames = []string{
+ // systemd < 209
+ "libsystemd-journal.so.0",
+ "libsystemd-journal.so",
+
+ // systemd >= 209 merged libsystemd-journal into libsystemd proper
+ "libsystemd.so.0",
+ "libsystemd.so",
+ }
+)
+
+func getFunction(name string) (unsafe.Pointer, error) {
+ libsystemdMutex.Lock()
+ defer libsystemdMutex.Unlock()
+
+ if libsystemdHandle == nil {
+ h, err := dlopen.GetHandle(libsystemdNames)
+ if err != nil {
+ return nil, err
+ }
+
+ libsystemdHandle = h
+ }
+
+ f, ok := libsystemdFunctions[name]
+ if !ok {
+ var err error
+ f, err = libsystemdHandle.GetSymbolPointer(name)
+ if err != nil {
+ return nil, err
+ }
+
+ libsystemdFunctions[name] = f
+ }
+
+ return f, nil
+}
diff --git a/vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go b/vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go
new file mode 100644
index 000000000..7f840def8
--- /dev/null
+++ b/vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go
@@ -0,0 +1,1120 @@
+// Copyright 2015 RedHat, Inc.
+// 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 sdjournal provides a low-level Go interface to the
+// systemd journal wrapped around the sd-journal C API.
+//
+// All public read methods map closely to the sd-journal API functions. See the
+// sd-journal.h documentation[1] for information about each function.
+//
+// To write to the journal, see the pure-Go "journal" package
+//
+// [1] http://www.freedesktop.org/software/systemd/man/sd-journal.html
+package sdjournal
+
+// #include <systemd/sd-journal.h>
+// #include <systemd/sd-id128.h>
+// #include <stdlib.h>
+// #include <syslog.h>
+//
+// int
+// my_sd_journal_open(void *f, sd_journal **ret, int flags)
+// {
+// int (*sd_journal_open)(sd_journal **, int);
+//
+// sd_journal_open = f;
+// return sd_journal_open(ret, flags);
+// }
+//
+// int
+// my_sd_journal_open_directory(void *f, sd_journal **ret, const char *path, int flags)
+// {
+// int (*sd_journal_open_directory)(sd_journal **, const char *, int);
+//
+// sd_journal_open_directory = f;
+// return sd_journal_open_directory(ret, path, flags);
+// }
+//
+// int
+// my_sd_journal_open_files(void *f, sd_journal **ret, const char **paths, int flags)
+// {
+// int (*sd_journal_open_files)(sd_journal **, const char **, int);
+//
+// sd_journal_open_files = f;
+// return sd_journal_open_files(ret, paths, flags);
+// }
+//
+// void
+// my_sd_journal_close(void *f, sd_journal *j)
+// {
+// int (*sd_journal_close)(sd_journal *);
+//
+// sd_journal_close = f;
+// sd_journal_close(j);
+// }
+//
+// int
+// my_sd_journal_get_usage(void *f, sd_journal *j, uint64_t *bytes)
+// {
+// int (*sd_journal_get_usage)(sd_journal *, uint64_t *);
+//
+// sd_journal_get_usage = f;
+// return sd_journal_get_usage(j, bytes);
+// }
+//
+// int
+// my_sd_journal_add_match(void *f, sd_journal *j, const void *data, size_t size)
+// {
+// int (*sd_journal_add_match)(sd_journal *, const void *, size_t);
+//
+// sd_journal_add_match = f;
+// return sd_journal_add_match(j, data, size);
+// }
+//
+// int
+// my_sd_journal_add_disjunction(void *f, sd_journal *j)
+// {
+// int (*sd_journal_add_disjunction)(sd_journal *);
+//
+// sd_journal_add_disjunction = f;
+// return sd_journal_add_disjunction(j);
+// }
+//
+// int
+// my_sd_journal_add_conjunction(void *f, sd_journal *j)
+// {
+// int (*sd_journal_add_conjunction)(sd_journal *);
+//
+// sd_journal_add_conjunction = f;
+// return sd_journal_add_conjunction(j);
+// }
+//
+// void
+// my_sd_journal_flush_matches(void *f, sd_journal *j)
+// {
+// int (*sd_journal_flush_matches)(sd_journal *);
+//
+// sd_journal_flush_matches = f;
+// sd_journal_flush_matches(j);
+// }
+//
+// int
+// my_sd_journal_next(void *f, sd_journal *j)
+// {
+// int (*sd_journal_next)(sd_journal *);
+//
+// sd_journal_next = f;
+// return sd_journal_next(j);
+// }
+//
+// int
+// my_sd_journal_next_skip(void *f, sd_journal *j, uint64_t skip)
+// {
+// int (*sd_journal_next_skip)(sd_journal *, uint64_t);
+//
+// sd_journal_next_skip = f;
+// return sd_journal_next_skip(j, skip);
+// }
+//
+// int
+// my_sd_journal_previous(void *f, sd_journal *j)
+// {
+// int (*sd_journal_previous)(sd_journal *);
+//
+// sd_journal_previous = f;
+// return sd_journal_previous(j);
+// }
+//
+// int
+// my_sd_journal_previous_skip(void *f, sd_journal *j, uint64_t skip)
+// {
+// int (*sd_journal_previous_skip)(sd_journal *, uint64_t);
+//
+// sd_journal_previous_skip = f;
+// return sd_journal_previous_skip(j, skip);
+// }
+//
+// int
+// my_sd_journal_get_data(void *f, sd_journal *j, const char *field, const void **data, size_t *length)
+// {
+// int (*sd_journal_get_data)(sd_journal *, const char *, const void **, size_t *);
+//
+// sd_journal_get_data = f;
+// return sd_journal_get_data(j, field, data, length);
+// }
+//
+// int
+// my_sd_journal_set_data_threshold(void *f, sd_journal *j, size_t sz)
+// {
+// int (*sd_journal_set_data_threshold)(sd_journal *, size_t);
+//
+// sd_journal_set_data_threshold = f;
+// return sd_journal_set_data_threshold(j, sz);
+// }
+//
+// int
+// my_sd_journal_get_cursor(void *f, sd_journal *j, char **cursor)
+// {
+// int (*sd_journal_get_cursor)(sd_journal *, char **);
+//
+// sd_journal_get_cursor = f;
+// return sd_journal_get_cursor(j, cursor);
+// }
+//
+// int
+// my_sd_journal_test_cursor(void *f, sd_journal *j, const char *cursor)
+// {
+// int (*sd_journal_test_cursor)(sd_journal *, const char *);
+//
+// sd_journal_test_cursor = f;
+// return sd_journal_test_cursor(j, cursor);
+// }
+//
+// int
+// my_sd_journal_get_realtime_usec(void *f, sd_journal *j, uint64_t *usec)
+// {
+// int (*sd_journal_get_realtime_usec)(sd_journal *, uint64_t *);
+//
+// sd_journal_get_realtime_usec = f;
+// return sd_journal_get_realtime_usec(j, usec);
+// }
+//
+// int
+// my_sd_journal_get_monotonic_usec(void *f, sd_journal *j, uint64_t *usec, sd_id128_t *boot_id)
+// {
+// int (*sd_journal_get_monotonic_usec)(sd_journal *, uint64_t *, sd_id128_t *);
+//
+// sd_journal_get_monotonic_usec = f;
+// return sd_journal_get_monotonic_usec(j, usec, boot_id);
+// }
+//
+// int
+// my_sd_journal_seek_head(void *f, sd_journal *j)
+// {
+// int (*sd_journal_seek_head)(sd_journal *);
+//
+// sd_journal_seek_head = f;
+// return sd_journal_seek_head(j);
+// }
+//
+// int
+// my_sd_journal_seek_tail(void *f, sd_journal *j)
+// {
+// int (*sd_journal_seek_tail)(sd_journal *);
+//
+// sd_journal_seek_tail = f;
+// return sd_journal_seek_tail(j);
+// }
+//
+//
+// int
+// my_sd_journal_seek_cursor(void *f, sd_journal *j, const char *cursor)
+// {
+// int (*sd_journal_seek_cursor)(sd_journal *, const char *);
+//
+// sd_journal_seek_cursor = f;
+// return sd_journal_seek_cursor(j, cursor);
+// }
+//
+// int
+// my_sd_journal_seek_realtime_usec(void *f, sd_journal *j, uint64_t usec)
+// {
+// int (*sd_journal_seek_realtime_usec)(sd_journal *, uint64_t);
+//
+// sd_journal_seek_realtime_usec = f;
+// return sd_journal_seek_realtime_usec(j, usec);
+// }
+//
+// int
+// my_sd_journal_wait(void *f, sd_journal *j, uint64_t timeout_usec)
+// {
+// int (*sd_journal_wait)(sd_journal *, uint64_t);
+//
+// sd_journal_wait = f;
+// return sd_journal_wait(j, timeout_usec);
+// }
+//
+// void
+// my_sd_journal_restart_data(void *f, sd_journal *j)
+// {
+// void (*sd_journal_restart_data)(sd_journal *);
+//
+// sd_journal_restart_data = f;
+// sd_journal_restart_data(j);
+// }
+//
+// int
+// my_sd_journal_enumerate_data(void *f, sd_journal *j, const void **data, size_t *length)
+// {
+// int (*sd_journal_enumerate_data)(sd_journal *, const void **, size_t *);
+//
+// sd_journal_enumerate_data = f;
+// return sd_journal_enumerate_data(j, data, length);
+// }
+//
+// int
+// my_sd_journal_query_unique(void *f, sd_journal *j, const char *field)
+// {
+// int(*sd_journal_query_unique)(sd_journal *, const char *);
+//
+// sd_journal_query_unique = f;
+// return sd_journal_query_unique(j, field);
+// }
+//
+// int
+// my_sd_journal_enumerate_unique(void *f, sd_journal *j, const void **data, size_t *length)
+// {
+// int(*sd_journal_enumerate_unique)(sd_journal *, const void **, size_t *);
+//
+// sd_journal_enumerate_unique = f;
+// return sd_journal_enumerate_unique(j, data, length);
+// }
+//
+// void
+// my_sd_journal_restart_unique(void *f, sd_journal *j)
+// {
+// void(*sd_journal_restart_unique)(sd_journal *);
+//
+// sd_journal_restart_unique = f;
+// sd_journal_restart_unique(j);
+// }
+//
+// int
+// my_sd_journal_get_catalog(void *f, sd_journal *j, char **ret)
+// {
+// int(*sd_journal_get_catalog)(sd_journal *, char **);
+//
+// sd_journal_get_catalog = f;
+// return sd_journal_get_catalog(j, ret);
+// }
+//
+import "C"
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "strings"
+ "sync"
+ "syscall"
+ "time"
+ "unsafe"
+)
+
+// Journal entry field strings which correspond to:
+// http://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html
+const (
+ // User Journal Fields
+ SD_JOURNAL_FIELD_MESSAGE = "MESSAGE"
+ SD_JOURNAL_FIELD_MESSAGE_ID = "MESSAGE_ID"
+ SD_JOURNAL_FIELD_PRIORITY = "PRIORITY"
+ SD_JOURNAL_FIELD_CODE_FILE = "CODE_FILE"
+ SD_JOURNAL_FIELD_CODE_LINE = "CODE_LINE"
+ SD_JOURNAL_FIELD_CODE_FUNC = "CODE_FUNC"
+ SD_JOURNAL_FIELD_ERRNO = "ERRNO"
+ SD_JOURNAL_FIELD_SYSLOG_FACILITY = "SYSLOG_FACILITY"
+ SD_JOURNAL_FIELD_SYSLOG_IDENTIFIER = "SYSLOG_IDENTIFIER"
+ SD_JOURNAL_FIELD_SYSLOG_PID = "SYSLOG_PID"
+
+ // Trusted Journal Fields
+ SD_JOURNAL_FIELD_PID = "_PID"
+ SD_JOURNAL_FIELD_UID = "_UID"
+ SD_JOURNAL_FIELD_GID = "_GID"
+ SD_JOURNAL_FIELD_COMM = "_COMM"
+ SD_JOURNAL_FIELD_EXE = "_EXE"
+ SD_JOURNAL_FIELD_CMDLINE = "_CMDLINE"
+ SD_JOURNAL_FIELD_CAP_EFFECTIVE = "_CAP_EFFECTIVE"
+ SD_JOURNAL_FIELD_AUDIT_SESSION = "_AUDIT_SESSION"
+ SD_JOURNAL_FIELD_AUDIT_LOGINUID = "_AUDIT_LOGINUID"
+ SD_JOURNAL_FIELD_SYSTEMD_CGROUP = "_SYSTEMD_CGROUP"
+ SD_JOURNAL_FIELD_SYSTEMD_SESSION = "_SYSTEMD_SESSION"
+ SD_JOURNAL_FIELD_SYSTEMD_UNIT = "_SYSTEMD_UNIT"
+ SD_JOURNAL_FIELD_SYSTEMD_USER_UNIT = "_SYSTEMD_USER_UNIT"
+ SD_JOURNAL_FIELD_SYSTEMD_OWNER_UID = "_SYSTEMD_OWNER_UID"
+ SD_JOURNAL_FIELD_SYSTEMD_SLICE = "_SYSTEMD_SLICE"
+ SD_JOURNAL_FIELD_SELINUX_CONTEXT = "_SELINUX_CONTEXT"
+ SD_JOURNAL_FIELD_SOURCE_REALTIME_TIMESTAMP = "_SOURCE_REALTIME_TIMESTAMP"
+ SD_JOURNAL_FIELD_BOOT_ID = "_BOOT_ID"
+ SD_JOURNAL_FIELD_MACHINE_ID = "_MACHINE_ID"
+ SD_JOURNAL_FIELD_HOSTNAME = "_HOSTNAME"
+ SD_JOURNAL_FIELD_TRANSPORT = "_TRANSPORT"
+
+ // Address Fields
+ SD_JOURNAL_FIELD_CURSOR = "__CURSOR"
+ SD_JOURNAL_FIELD_REALTIME_TIMESTAMP = "__REALTIME_TIMESTAMP"
+ SD_JOURNAL_FIELD_MONOTONIC_TIMESTAMP = "__MONOTONIC_TIMESTAMP"
+)
+
+// Journal event constants
+const (
+ SD_JOURNAL_NOP = int(C.SD_JOURNAL_NOP)
+ SD_JOURNAL_APPEND = int(C.SD_JOURNAL_APPEND)
+ SD_JOURNAL_INVALIDATE = int(C.SD_JOURNAL_INVALIDATE)
+)
+
+const (
+ // IndefiniteWait is a sentinel value that can be passed to
+ // sdjournal.Wait() to signal an indefinite wait for new journal
+ // events. It is implemented as the maximum value for a time.Duration:
+ // https://github.com/golang/go/blob/e4dcf5c8c22d98ac9eac7b9b226596229624cb1d/src/time/time.go#L434
+ IndefiniteWait time.Duration = 1<<63 - 1
+)
+
+var (
+ // ErrNoTestCursor gets returned when using TestCursor function and cursor
+ // parameter is not the same as the current cursor position.
+ ErrNoTestCursor = errors.New("Cursor parameter is not the same as current position")
+)
+
+// Journal is a Go wrapper of an sd_journal structure.
+type Journal struct {
+ cjournal *C.sd_journal
+ mu sync.Mutex
+}
+
+// JournalEntry represents all fields of a journal entry plus address fields.
+type JournalEntry struct {
+ Fields map[string]string
+ Cursor string
+ RealtimeTimestamp uint64
+ MonotonicTimestamp uint64
+}
+
+// Match is a convenience wrapper to describe filters supplied to AddMatch.
+type Match struct {
+ Field string
+ Value string
+}
+
+// String returns a string representation of a Match suitable for use with AddMatch.
+func (m *Match) String() string {
+ return m.Field + "=" + m.Value
+}
+
+// NewJournal returns a new Journal instance pointing to the local journal
+func NewJournal() (j *Journal, err error) {
+ j = &Journal{}
+
+ sd_journal_open, err := getFunction("sd_journal_open")
+ if err != nil {
+ return nil, err
+ }
+
+ r := C.my_sd_journal_open(sd_journal_open, &j.cjournal, C.SD_JOURNAL_LOCAL_ONLY)
+
+ if r < 0 {
+ return nil, fmt.Errorf("failed to open journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return j, nil
+}
+
+// NewJournalFromDir returns a new Journal instance pointing to a journal residing
+// in a given directory.
+func NewJournalFromDir(path string) (j *Journal, err error) {
+ j = &Journal{}
+
+ sd_journal_open_directory, err := getFunction("sd_journal_open_directory")
+ if err != nil {
+ return nil, err
+ }
+
+ p := C.CString(path)
+ defer C.free(unsafe.Pointer(p))
+
+ r := C.my_sd_journal_open_directory(sd_journal_open_directory, &j.cjournal, p, 0)
+ if r < 0 {
+ return nil, fmt.Errorf("failed to open journal in directory %q: %s", path, syscall.Errno(-r).Error())
+ }
+
+ return j, nil
+}
+
+// NewJournalFromFiles returns a new Journal instance pointing to a journals residing
+// in a given files.
+func NewJournalFromFiles(paths ...string) (j *Journal, err error) {
+ j = &Journal{}
+
+ sd_journal_open_files, err := getFunction("sd_journal_open_files")
+ if err != nil {
+ return nil, err
+ }
+
+ // by making the slice 1 elem too long, we guarantee it'll be null-terminated
+ cPaths := make([]*C.char, len(paths)+1)
+ for idx, path := range paths {
+ p := C.CString(path)
+ cPaths[idx] = p
+ defer C.free(unsafe.Pointer(p))
+ }
+
+ r := C.my_sd_journal_open_files(sd_journal_open_files, &j.cjournal, &cPaths[0], 0)
+ if r < 0 {
+ return nil, fmt.Errorf("failed to open journals in paths %q: %s", paths, syscall.Errno(-r).Error())
+ }
+
+ return j, nil
+}
+
+// Close closes a journal opened with NewJournal.
+func (j *Journal) Close() error {
+ sd_journal_close, err := getFunction("sd_journal_close")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ C.my_sd_journal_close(sd_journal_close, j.cjournal)
+ j.mu.Unlock()
+
+ return nil
+}
+
+// AddMatch adds a match by which to filter the entries of the journal.
+func (j *Journal) AddMatch(match string) error {
+ sd_journal_add_match, err := getFunction("sd_journal_add_match")
+ if err != nil {
+ return err
+ }
+
+ m := C.CString(match)
+ defer C.free(unsafe.Pointer(m))
+
+ j.mu.Lock()
+ r := C.my_sd_journal_add_match(sd_journal_add_match, j.cjournal, unsafe.Pointer(m), C.size_t(len(match)))
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to add match: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// AddDisjunction inserts a logical OR in the match list.
+func (j *Journal) AddDisjunction() error {
+ sd_journal_add_disjunction, err := getFunction("sd_journal_add_disjunction")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_add_disjunction(sd_journal_add_disjunction, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to add a disjunction in the match list: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// AddConjunction inserts a logical AND in the match list.
+func (j *Journal) AddConjunction() error {
+ sd_journal_add_conjunction, err := getFunction("sd_journal_add_conjunction")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_add_conjunction(sd_journal_add_conjunction, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to add a conjunction in the match list: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// FlushMatches flushes all matches, disjunctions and conjunctions.
+func (j *Journal) FlushMatches() {
+ sd_journal_flush_matches, err := getFunction("sd_journal_flush_matches")
+ if err != nil {
+ return
+ }
+
+ j.mu.Lock()
+ C.my_sd_journal_flush_matches(sd_journal_flush_matches, j.cjournal)
+ j.mu.Unlock()
+}
+
+// Next advances the read pointer into the journal by one entry.
+func (j *Journal) Next() (uint64, error) {
+ sd_journal_next, err := getFunction("sd_journal_next")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_next(sd_journal_next, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to iterate journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(r), nil
+}
+
+// NextSkip advances the read pointer by multiple entries at once,
+// as specified by the skip parameter.
+func (j *Journal) NextSkip(skip uint64) (uint64, error) {
+ sd_journal_next_skip, err := getFunction("sd_journal_next_skip")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_next_skip(sd_journal_next_skip, j.cjournal, C.uint64_t(skip))
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to iterate journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(r), nil
+}
+
+// Previous sets the read pointer into the journal back by one entry.
+func (j *Journal) Previous() (uint64, error) {
+ sd_journal_previous, err := getFunction("sd_journal_previous")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_previous(sd_journal_previous, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to iterate journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(r), nil
+}
+
+// PreviousSkip sets back the read pointer by multiple entries at once,
+// as specified by the skip parameter.
+func (j *Journal) PreviousSkip(skip uint64) (uint64, error) {
+ sd_journal_previous_skip, err := getFunction("sd_journal_previous_skip")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_previous_skip(sd_journal_previous_skip, j.cjournal, C.uint64_t(skip))
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to iterate journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(r), nil
+}
+
+func (j *Journal) getData(field string) (unsafe.Pointer, C.int, error) {
+ sd_journal_get_data, err := getFunction("sd_journal_get_data")
+ if err != nil {
+ return nil, 0, err
+ }
+
+ f := C.CString(field)
+ defer C.free(unsafe.Pointer(f))
+
+ var d unsafe.Pointer
+ var l C.size_t
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_data(sd_journal_get_data, j.cjournal, f, &d, &l)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return nil, 0, fmt.Errorf("failed to read message: %s", syscall.Errno(-r).Error())
+ }
+
+ return d, C.int(l), nil
+}
+
+// GetData gets the data object associated with a specific field from the
+// the journal entry referenced by the last completed Next/Previous function
+// call. To call GetData, you must have first called one of these functions.
+func (j *Journal) GetData(field string) (string, error) {
+ d, l, err := j.getData(field)
+ if err != nil {
+ return "", err
+ }
+
+ return C.GoStringN((*C.char)(d), l), nil
+}
+
+// GetDataValue gets the data object associated with a specific field from the
+// journal entry referenced by the last completed Next/Previous function call,
+// returning only the value of the object. To call GetDataValue, you must first
+// have called one of the Next/Previous functions.
+func (j *Journal) GetDataValue(field string) (string, error) {
+ val, err := j.GetData(field)
+ if err != nil {
+ return "", err
+ }
+
+ return strings.SplitN(val, "=", 2)[1], nil
+}
+
+// GetDataBytes gets the data object associated with a specific field from the
+// journal entry referenced by the last completed Next/Previous function call.
+// To call GetDataBytes, you must first have called one of these functions.
+func (j *Journal) GetDataBytes(field string) ([]byte, error) {
+ d, l, err := j.getData(field)
+ if err != nil {
+ return nil, err
+ }
+
+ return C.GoBytes(d, l), nil
+}
+
+// GetDataValueBytes gets the data object associated with a specific field from the
+// journal entry referenced by the last completed Next/Previous function call,
+// returning only the value of the object. To call GetDataValueBytes, you must first
+// have called one of the Next/Previous functions.
+func (j *Journal) GetDataValueBytes(field string) ([]byte, error) {
+ val, err := j.GetDataBytes(field)
+ if err != nil {
+ return nil, err
+ }
+
+ return bytes.SplitN(val, []byte("="), 2)[1], nil
+}
+
+// GetEntry returns a full representation of the journal entry referenced by the
+// last completed Next/Previous function call, with all key-value pairs of data
+// as well as address fields (cursor, realtime timestamp and monotonic timestamp).
+// To call GetEntry, you must first have called one of the Next/Previous functions.
+func (j *Journal) GetEntry() (*JournalEntry, error) {
+ sd_journal_get_realtime_usec, err := getFunction("sd_journal_get_realtime_usec")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_get_monotonic_usec, err := getFunction("sd_journal_get_monotonic_usec")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_get_cursor, err := getFunction("sd_journal_get_cursor")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_restart_data, err := getFunction("sd_journal_restart_data")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_enumerate_data, err := getFunction("sd_journal_enumerate_data")
+ if err != nil {
+ return nil, err
+ }
+
+ j.mu.Lock()
+ defer j.mu.Unlock()
+
+ var r C.int
+ entry := &JournalEntry{Fields: make(map[string]string)}
+
+ var realtimeUsec C.uint64_t
+ r = C.my_sd_journal_get_realtime_usec(sd_journal_get_realtime_usec, j.cjournal, &realtimeUsec)
+ if r < 0 {
+ return nil, fmt.Errorf("failed to get realtime timestamp: %s", syscall.Errno(-r).Error())
+ }
+
+ entry.RealtimeTimestamp = uint64(realtimeUsec)
+
+ var monotonicUsec C.uint64_t
+ var boot_id C.sd_id128_t
+
+ r = C.my_sd_journal_get_monotonic_usec(sd_journal_get_monotonic_usec, j.cjournal, &monotonicUsec, &boot_id)
+ if r < 0 {
+ return nil, fmt.Errorf("failed to get monotonic timestamp: %s", syscall.Errno(-r).Error())
+ }
+
+ entry.MonotonicTimestamp = uint64(monotonicUsec)
+
+ var c *C.char
+ // since the pointer is mutated by sd_journal_get_cursor, need to wait
+ // until after the call to free the memory
+ r = C.my_sd_journal_get_cursor(sd_journal_get_cursor, j.cjournal, &c)
+ defer C.free(unsafe.Pointer(c))
+ if r < 0 {
+ return nil, fmt.Errorf("failed to get cursor: %s", syscall.Errno(-r).Error())
+ }
+
+ entry.Cursor = C.GoString(c)
+
+ // Implements the JOURNAL_FOREACH_DATA_RETVAL macro from journal-internal.h
+ var d unsafe.Pointer
+ var l C.size_t
+ C.my_sd_journal_restart_data(sd_journal_restart_data, j.cjournal)
+ for {
+ r = C.my_sd_journal_enumerate_data(sd_journal_enumerate_data, j.cjournal, &d, &l)
+ if r == 0 {
+ break
+ }
+
+ if r < 0 {
+ return nil, fmt.Errorf("failed to read message field: %s", syscall.Errno(-r).Error())
+ }
+
+ msg := C.GoStringN((*C.char)(d), C.int(l))
+ kv := strings.SplitN(msg, "=", 2)
+ if len(kv) < 2 {
+ return nil, fmt.Errorf("failed to parse field")
+ }
+
+ entry.Fields[kv[0]] = kv[1]
+ }
+
+ return entry, nil
+}
+
+// SetDataThreshold sets the data field size threshold for data returned by
+// GetData. To retrieve the complete data fields this threshold should be
+// turned off by setting it to 0, so that the library always returns the
+// complete data objects.
+func (j *Journal) SetDataThreshold(threshold uint64) error {
+ sd_journal_set_data_threshold, err := getFunction("sd_journal_set_data_threshold")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_set_data_threshold(sd_journal_set_data_threshold, j.cjournal, C.size_t(threshold))
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to set data threshold: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// GetRealtimeUsec gets the realtime (wallclock) timestamp of the journal
+// entry referenced by the last completed Next/Previous function call. To
+// call GetRealtimeUsec, you must first have called one of the Next/Previous
+// functions.
+func (j *Journal) GetRealtimeUsec() (uint64, error) {
+ var usec C.uint64_t
+
+ sd_journal_get_realtime_usec, err := getFunction("sd_journal_get_realtime_usec")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_realtime_usec(sd_journal_get_realtime_usec, j.cjournal, &usec)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to get realtime timestamp: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(usec), nil
+}
+
+// GetMonotonicUsec gets the monotonic timestamp of the journal entry
+// referenced by the last completed Next/Previous function call. To call
+// GetMonotonicUsec, you must first have called one of the Next/Previous
+// functions.
+func (j *Journal) GetMonotonicUsec() (uint64, error) {
+ var usec C.uint64_t
+ var boot_id C.sd_id128_t
+
+ sd_journal_get_monotonic_usec, err := getFunction("sd_journal_get_monotonic_usec")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_monotonic_usec(sd_journal_get_monotonic_usec, j.cjournal, &usec, &boot_id)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to get monotonic timestamp: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(usec), nil
+}
+
+// GetCursor gets the cursor of the last journal entry reeferenced by the
+// last completed Next/Previous function call. To call GetCursor, you must
+// first have called one of the Next/Previous functions.
+func (j *Journal) GetCursor() (string, error) {
+ sd_journal_get_cursor, err := getFunction("sd_journal_get_cursor")
+ if err != nil {
+ return "", err
+ }
+
+ var d *C.char
+ // since the pointer is mutated by sd_journal_get_cursor, need to wait
+ // until after the call to free the memory
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_cursor(sd_journal_get_cursor, j.cjournal, &d)
+ j.mu.Unlock()
+ defer C.free(unsafe.Pointer(d))
+
+ if r < 0 {
+ return "", fmt.Errorf("failed to get cursor: %s", syscall.Errno(-r).Error())
+ }
+
+ cursor := C.GoString(d)
+
+ return cursor, nil
+}
+
+// TestCursor checks whether the current position in the journal matches the
+// specified cursor
+func (j *Journal) TestCursor(cursor string) error {
+ sd_journal_test_cursor, err := getFunction("sd_journal_test_cursor")
+ if err != nil {
+ return err
+ }
+
+ c := C.CString(cursor)
+ defer C.free(unsafe.Pointer(c))
+
+ j.mu.Lock()
+ r := C.my_sd_journal_test_cursor(sd_journal_test_cursor, j.cjournal, c)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to test to cursor %q: %s", cursor, syscall.Errno(-r).Error())
+ } else if r == 0 {
+ return ErrNoTestCursor
+ }
+
+ return nil
+}
+
+// SeekHead seeks to the beginning of the journal, i.e. the oldest available
+// entry. This call must be followed by a call to Next before any call to
+// Get* will return data about the first element.
+func (j *Journal) SeekHead() error {
+ sd_journal_seek_head, err := getFunction("sd_journal_seek_head")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_seek_head(sd_journal_seek_head, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to seek to head of journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// SeekTail may be used to seek to the end of the journal, i.e. the most recent
+// available entry. This call must be followed by a call to Next before any
+// call to Get* will return data about the last element.
+func (j *Journal) SeekTail() error {
+ sd_journal_seek_tail, err := getFunction("sd_journal_seek_tail")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_seek_tail(sd_journal_seek_tail, j.cjournal)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to seek to tail of journal: %s", syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// SeekRealtimeUsec seeks to the entry with the specified realtime (wallclock)
+// timestamp, i.e. CLOCK_REALTIME. This call must be followed by a call to
+// Next/Previous before any call to Get* will return data about the sought entry.
+func (j *Journal) SeekRealtimeUsec(usec uint64) error {
+ sd_journal_seek_realtime_usec, err := getFunction("sd_journal_seek_realtime_usec")
+ if err != nil {
+ return err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_seek_realtime_usec(sd_journal_seek_realtime_usec, j.cjournal, C.uint64_t(usec))
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to seek to %d: %s", usec, syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// SeekCursor seeks to a concrete journal cursor. This call must be
+// followed by a call to Next/Previous before any call to Get* will return
+// data about the sought entry.
+func (j *Journal) SeekCursor(cursor string) error {
+ sd_journal_seek_cursor, err := getFunction("sd_journal_seek_cursor")
+ if err != nil {
+ return err
+ }
+
+ c := C.CString(cursor)
+ defer C.free(unsafe.Pointer(c))
+
+ j.mu.Lock()
+ r := C.my_sd_journal_seek_cursor(sd_journal_seek_cursor, j.cjournal, c)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return fmt.Errorf("failed to seek to cursor %q: %s", cursor, syscall.Errno(-r).Error())
+ }
+
+ return nil
+}
+
+// Wait will synchronously wait until the journal gets changed. The maximum time
+// this call sleeps may be controlled with the timeout parameter. If
+// sdjournal.IndefiniteWait is passed as the timeout parameter, Wait will
+// wait indefinitely for a journal change.
+func (j *Journal) Wait(timeout time.Duration) int {
+ var to uint64
+
+ sd_journal_wait, err := getFunction("sd_journal_wait")
+ if err != nil {
+ return -1
+ }
+
+ if timeout == IndefiniteWait {
+ // sd_journal_wait(3) calls for a (uint64_t) -1 to be passed to signify
+ // indefinite wait, but using a -1 overflows our C.uint64_t, so we use an
+ // equivalent hex value.
+ to = 0xffffffffffffffff
+ } else {
+ to = uint64(timeout / time.Microsecond)
+ }
+ j.mu.Lock()
+ r := C.my_sd_journal_wait(sd_journal_wait, j.cjournal, C.uint64_t(to))
+ j.mu.Unlock()
+
+ return int(r)
+}
+
+// GetUsage returns the journal disk space usage, in bytes.
+func (j *Journal) GetUsage() (uint64, error) {
+ var out C.uint64_t
+
+ sd_journal_get_usage, err := getFunction("sd_journal_get_usage")
+ if err != nil {
+ return 0, err
+ }
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_usage(sd_journal_get_usage, j.cjournal, &out)
+ j.mu.Unlock()
+
+ if r < 0 {
+ return 0, fmt.Errorf("failed to get journal disk space usage: %s", syscall.Errno(-r).Error())
+ }
+
+ return uint64(out), nil
+}
+
+// GetUniqueValues returns all unique values for a given field.
+func (j *Journal) GetUniqueValues(field string) ([]string, error) {
+ var result []string
+
+ sd_journal_query_unique, err := getFunction("sd_journal_query_unique")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_enumerate_unique, err := getFunction("sd_journal_enumerate_unique")
+ if err != nil {
+ return nil, err
+ }
+
+ sd_journal_restart_unique, err := getFunction("sd_journal_restart_unique")
+ if err != nil {
+ return nil, err
+ }
+
+ j.mu.Lock()
+ defer j.mu.Unlock()
+
+ f := C.CString(field)
+ defer C.free(unsafe.Pointer(f))
+
+ r := C.my_sd_journal_query_unique(sd_journal_query_unique, j.cjournal, f)
+
+ if r < 0 {
+ return nil, fmt.Errorf("failed to query journal: %s", syscall.Errno(-r).Error())
+ }
+
+ // Implements the SD_JOURNAL_FOREACH_UNIQUE macro from sd-journal.h
+ var d unsafe.Pointer
+ var l C.size_t
+ C.my_sd_journal_restart_unique(sd_journal_restart_unique, j.cjournal)
+ for {
+ r = C.my_sd_journal_enumerate_unique(sd_journal_enumerate_unique, j.cjournal, &d, &l)
+ if r == 0 {
+ break
+ }
+
+ if r < 0 {
+ return nil, fmt.Errorf("failed to read message field: %s", syscall.Errno(-r).Error())
+ }
+
+ msg := C.GoStringN((*C.char)(d), C.int(l))
+ kv := strings.SplitN(msg, "=", 2)
+ if len(kv) < 2 {
+ return nil, fmt.Errorf("failed to parse field")
+ }
+
+ result = append(result, kv[1])
+ }
+
+ return result, nil
+}
+
+// GetCatalog retrieves a message catalog entry for the journal entry referenced
+// by the last completed Next/Previous function call. To call GetCatalog, you
+// must first have called one of these functions.
+func (j *Journal) GetCatalog() (string, error) {
+ sd_journal_get_catalog, err := getFunction("sd_journal_get_catalog")
+ if err != nil {
+ return "", err
+ }
+
+ var c *C.char
+
+ j.mu.Lock()
+ r := C.my_sd_journal_get_catalog(sd_journal_get_catalog, j.cjournal, &c)
+ j.mu.Unlock()
+ defer C.free(unsafe.Pointer(c))
+
+ if r < 0 {
+ return "", fmt.Errorf("failed to retrieve catalog entry for current journal entry: %s", syscall.Errno(-r).Error())
+ }
+
+ catalog := C.GoString(c)
+
+ return catalog, nil
+}
diff --git a/vendor/github.com/coreos/go-systemd/v22/sdjournal/read.go b/vendor/github.com/coreos/go-systemd/v22/sdjournal/read.go
new file mode 100644
index 000000000..51a060fb5
--- /dev/null
+++ b/vendor/github.com/coreos/go-systemd/v22/sdjournal/read.go
@@ -0,0 +1,272 @@
+// Copyright 2015 RedHat, Inc.
+// 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 sdjournal
+
+import (
+ "errors"
+ "fmt"
+ "io"
+ "log"
+ "strings"
+ "sync"
+ "time"
+)
+
+var (
+ // ErrExpired gets returned when the Follow function runs into the
+ // specified timeout.
+ ErrExpired = errors.New("Timeout expired")
+)
+
+// JournalReaderConfig represents options to drive the behavior of a JournalReader.
+type JournalReaderConfig struct {
+ // The Since, NumFromTail and Cursor options are mutually exclusive and
+ // determine where the reading begins within the journal. The order in which
+ // options are written is exactly the order of precedence.
+ Since time.Duration // start relative to a Duration from now
+ NumFromTail uint64 // start relative to the tail
+ Cursor string // start relative to the cursor
+
+ // Show only journal entries whose fields match the supplied values. If
+ // the array is empty, entries will not be filtered.
+ Matches []Match
+
+ // If not empty, the journal instance will point to a journal residing
+ // in this directory. The supplied path may be relative or absolute.
+ Path string
+
+ // If not nil, Formatter will be used to translate the resulting entries
+ // into strings. If not set, the default format (timestamp and message field)
+ // will be used. If Formatter returns an error, Read will stop and return the error.
+ Formatter func(entry *JournalEntry) (string, error)
+}
+
+// JournalReader is an io.ReadCloser which provides a simple interface for iterating through the
+// systemd journal. A JournalReader is not safe for concurrent use by multiple goroutines.
+type JournalReader struct {
+ journal *Journal
+ msgReader *strings.Reader
+ formatter func(entry *JournalEntry) (string, error)
+}
+
+// NewJournalReader creates a new JournalReader with configuration options that are similar to the
+// systemd journalctl tool's iteration and filtering features.
+func NewJournalReader(config JournalReaderConfig) (*JournalReader, error) {
+ // use simpleMessageFormatter as default formatter.
+ if config.Formatter == nil {
+ config.Formatter = simpleMessageFormatter
+ }
+
+ r := &JournalReader{
+ formatter: config.Formatter,
+ }
+
+ // Open the journal
+ var err error
+ if config.Path != "" {
+ r.journal, err = NewJournalFromDir(config.Path)
+ } else {
+ r.journal, err = NewJournal()
+ }
+ if err != nil {
+ return nil, err
+ }
+
+ // Add any supplied matches
+ for _, m := range config.Matches {
+ if err = r.journal.AddMatch(m.String()); err != nil {
+ return nil, err
+ }
+ }
+
+ // Set the start position based on options
+ if config.Since != 0 {
+ // Start based on a relative time
+ start := time.Now().Add(config.Since)
+ if err := r.journal.SeekRealtimeUsec(uint64(start.UnixNano() / 1000)); err != nil {
+ return nil, err
+ }
+ } else if config.NumFromTail != 0 {
+ // Start based on a number of lines before the tail
+ if err := r.journal.SeekTail(); err != nil {
+ return nil, err
+ }
+
+ // Move the read pointer into position near the tail. Go one further than
+ // the option so that the initial cursor advancement positions us at the
+ // correct starting point.
+ skip, err := r.journal.PreviousSkip(config.NumFromTail + 1)
+ if err != nil {
+ return nil, err
+ }
+ // If we skipped fewer lines than expected, we have reached journal start.
+ // Thus, we seek to head so that next invocation can read the first line.
+ if skip != config.NumFromTail+1 {
+ if err := r.journal.SeekHead(); err != nil {
+ return nil, err
+ }
+ }
+ } else if config.Cursor != "" {
+ // Start based on a custom cursor
+ if err := r.journal.SeekCursor(config.Cursor); err != nil {
+ return nil, err
+ }
+ }
+
+ return r, nil
+}
+
+// Read reads entries from the journal. Read follows the Reader interface so
+// it must be able to read a specific amount of bytes. Journald on the other
+// hand only allows us to read full entries of arbitrary size (without byte
+// granularity). JournalReader is therefore internally buffering entries that
+// don't fit in the read buffer. Callers should keep calling until 0 and/or an
+// error is returned.
+func (r *JournalReader) Read(b []byte) (int, error) {
+ if r.msgReader == nil {
+ // Advance the journal cursor. It has to be called at least one time
+ // before reading
+ c, err := r.journal.Next()
+
+ // An unexpected error
+ if err != nil {
+ return 0, err
+ }
+
+ // EOF detection
+ if c == 0 {
+ return 0, io.EOF
+ }
+
+ entry, err := r.journal.GetEntry()
+ if err != nil {
+ return 0, err
+ }
+
+ // Build a message
+ msg, err := r.formatter(entry)
+ if err != nil {
+ return 0, err
+ }
+ r.msgReader = strings.NewReader(msg)
+ }
+
+ // Copy and return the message
+ sz, err := r.msgReader.Read(b)
+ if err == io.EOF {
+ // The current entry has been fully read. Don't propagate this
+ // EOF, so the next entry can be read at the next Read()
+ // iteration.
+ r.msgReader = nil
+ return sz, nil
+ }
+ if err != nil {
+ return sz, err
+ }
+ if r.msgReader.Len() == 0 {
+ r.msgReader = nil
+ }
+
+ return sz, nil
+}
+
+// Close closes the JournalReader's handle to the journal.
+func (r *JournalReader) Close() error {
+ return r.journal.Close()
+}
+
+// Rewind attempts to rewind the JournalReader to the first entry.
+func (r *JournalReader) Rewind() error {
+ r.msgReader = nil
+ return r.journal.SeekHead()
+}
+
+// Follow synchronously follows the JournalReader, writing each new journal entry to writer. The
+// follow will continue until a single time.Time is received on the until channel.
+func (r *JournalReader) Follow(until <-chan time.Time, writer io.Writer) error {
+
+ // Process journal entries and events. Entries are flushed until the tail or
+ // timeout is reached, and then we wait for new events or the timeout.
+ var msg = make([]byte, 64*1<<(10))
+ var waitCh = make(chan int, 1)
+ var waitGroup sync.WaitGroup
+ defer waitGroup.Wait()
+
+process:
+ for {
+ c, err := r.Read(msg)
+ if err != nil && err != io.EOF {
+ return err
+ }
+
+ select {
+ case <-until:
+ return ErrExpired
+ default:
+ }
+ if c > 0 {
+ if _, err = writer.Write(msg[:c]); err != nil {
+ return err
+ }
+ continue process
+ }
+
+ // We're at the tail, so wait for new events or time out.
+ // Holds journal events to process. Tightly bounded for now unless there's a
+ // reason to unblock the journal watch routine more quickly.
+ for {
+ waitGroup.Add(1)
+ go func() {
+ status := r.journal.Wait(100 * time.Millisecond)
+ waitCh <- status
+ waitGroup.Done()
+ }()
+
+ select {
+ case <-until:
+ return ErrExpired
+ case e := <-waitCh:
+ switch e {
+ case SD_JOURNAL_NOP:
+ // the journal did not change since the last invocation
+ case SD_JOURNAL_APPEND, SD_JOURNAL_INVALIDATE:
+ continue process
+ default:
+ if e < 0 {
+ return fmt.Errorf("received error event: %d", e)
+ }
+
+ log.Printf("received unknown event: %d\n", e)
+ }
+ }
+ }
+ }
+}
+
+// simpleMessageFormatter is the default formatter.
+// It returns a string representing the current journal entry in a simple format which
+// includes the entry timestamp and MESSAGE field.
+func simpleMessageFormatter(entry *JournalEntry) (string, error) {
+ msg, ok := entry.Fields["MESSAGE"]
+ if !ok {
+ return "", fmt.Errorf("no MESSAGE field present in journal entry")
+ }
+
+ usec := entry.RealtimeTimestamp
+ timestamp := time.Unix(0, int64(usec)*int64(time.Microsecond))
+
+ return fmt.Sprintf("%s %s\n", timestamp, msg), nil
+}