From b5704dfcb29a942cd8569b9749653fdf5315d95b Mon Sep 17 00:00:00 2001 From: Daniel J Walsh Date: Thu, 15 Jul 2021 09:27:00 -0400 Subject: [PATCH] Switch default logdriver and eventslogger to journald, if root Signed-off-by: Daniel J Walsh --- Makefile | 11 +- go.mod | 1 + pkg/config/default.go | 2 - pkg/config/nosystemd.go | 7 +- pkg/config/systemd.go | 41 +- .../go-systemd/v22/internal/dlopen/dlopen.go | 82 ++ .../go-systemd/v22/sdjournal/functions.go | 66 + .../go-systemd/v22/sdjournal/journal.go | 1169 +++++++++++++++++ .../coreos/go-systemd/v22/sdjournal/read.go | 272 ++++ vendor/modules.txt | 3 + 10 files changed, 1640 insertions(+), 14 deletions(-) create mode 100644 vendor/github.com/coreos/go-systemd/v22/internal/dlopen/dlopen.go create mode 100644 vendor/github.com/coreos/go-systemd/v22/sdjournal/functions.go create mode 100644 vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go create mode 100644 vendor/github.com/coreos/go-systemd/v22/sdjournal/read.go diff --git a/Makefile b/Makefile index 10edc57a4..9c43ad284 100644 --- a/Makefile +++ b/Makefile @@ -6,7 +6,7 @@ GO_BUILD=$(GO) build ifeq ($(shell go help mod >/dev/null 2>&1 && echo true), true) GO_BUILD=GO111MODULE=on $(GO) build -mod=vendor endif -BUILDTAGS := containers_image_openpgp,systemd +BUILDTAGS := containers_image_openpgp,systemd,exclude_graphdriver_devicemapper DESTDIR ?= PREFIX := /usr/local CONFIGDIR := ${PREFIX}/share/containers @@ -35,8 +35,17 @@ define go-build GOOS=$(1) GOARCH=$(2) $(GO) build -tags "$(3)" ./... endef +define go-build-c + CGO_ENABLED=1 \ + GOOS=$(1) GOARCH=$(2) $(GO) build -tags "$(3)" ./... +endef + .PHONY: build-cross: + $(call go-build-c,linux) # attempt to build without tags + $(call go-build-c,linux,,${BUILDTAGS}) + $(call go-build-c,linux,386,${BUILDTAGS}) + $(call go-build,linux) # attempt to build without tags $(call go-build,linux,386,${BUILDTAGS}) $(call go-build,linux,arm,${BUILDTAGS}) $(call go-build,linux,arm64,${BUILDTAGS}) diff --git a/go.mod b/go.mod index fb86e5ad7..302119b52 100644 --- a/go.mod +++ b/go.mod @@ -7,6 +7,7 @@ require ( github.com/containers/image/v5 v5.13.2 github.com/containers/ocicrypt v1.1.2 github.com/containers/storage v1.32.6 + github.com/coreos/go-systemd/v22 v22.3.2 github.com/disiqueira/gotree/v3 v3.0.2 github.com/docker/distribution v2.7.1+incompatible github.com/docker/docker v20.10.7+incompatible diff --git a/pkg/config/default.go b/pkg/config/default.go index a16dd0e02..0e60c3f52 100644 --- a/pkg/config/default.go +++ b/pkg/config/default.go @@ -105,8 +105,6 @@ const ( DefaultApparmorProfile = apparmor.Profile // SystemdCgroupsManager represents systemd native cgroup manager SystemdCgroupsManager = "systemd" - // DefaultLogDriver is the default type of log files - DefaultLogDriver = "k8s-file" // DefaultLogSizeMax is the default value for the maximum log size // allowed for a container. Negative values mean that no limit is imposed. DefaultLogSizeMax = -1 diff --git a/pkg/config/nosystemd.go b/pkg/config/nosystemd.go index 6e39a6ccd..2a3b6fb35 100644 --- a/pkg/config/nosystemd.go +++ b/pkg/config/nosystemd.go @@ -1,7 +1,12 @@ -// +build !systemd +// +build !systemd !cgo package config +const ( + // DefaultLogDriver is the default type of log files + DefaultLogDriver = "k8s-file" +) + func defaultCgroupManager() string { return CgroupfsCgroupsManager } diff --git a/pkg/config/systemd.go b/pkg/config/systemd.go index ed014126b..fab3ea437 100644 --- a/pkg/config/systemd.go +++ b/pkg/config/systemd.go @@ -1,4 +1,4 @@ -// +build systemd +// +build systemd,cgo package config @@ -9,11 +9,19 @@ import ( "github.com/containers/common/pkg/cgroupv2" "github.com/containers/storage/pkg/unshare" + "github.com/coreos/go-systemd/v22/sdjournal" ) var ( - systemdOnce sync.Once - usesSystemd bool + systemdOnce sync.Once + usesSystemd bool + journaldOnce sync.Once + usesJournald bool +) + +const ( + // DefaultLogDriver is the default type of log files + DefaultLogDriver = "journald" ) func defaultCgroupManager() string { @@ -29,20 +37,17 @@ func defaultCgroupManager() string { } func defaultEventsLogger() string { - if useSystemd() { + if useJournald() { return "journald" } return "file" } func defaultLogDriver() string { - // If we decide to change the default for logdriver, it should be done here. - if useSystemd() { - return DefaultLogDriver + if useJournald() { + return "journald" } - - return DefaultLogDriver - + return "k8s-file" } func useSystemd() bool { @@ -56,3 +61,19 @@ func useSystemd() bool { }) return usesSystemd } + +func useJournald() bool { + journaldOnce.Do(func() { + if !useSystemd() { + return + } + journal, err := sdjournal.NewJournal() + if err != nil { + return + } + journal.Close() + usesJournald = true + return + }) + return usesJournald +} diff --git a/vendor/github.com/coreos/go-systemd/v22/internal/dlopen/dlopen.go b/vendor/github.com/coreos/go-systemd/v22/internal/dlopen/dlopen.go new file mode 100644 index 000000000..23774f612 --- /dev/null +++ b/vendor/github.com/coreos/go-systemd/v22/internal/dlopen/dlopen.go @@ -0,0 +1,82 @@ +// Copyright 2016 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 dlopen provides some convenience functions to dlopen a library and +// get its symbols. +package dlopen + +// #cgo LDFLAGS: -ldl +// #include +// #include +import "C" +import ( + "errors" + "fmt" + "unsafe" +) + +var ErrSoNotFound = errors.New("unable to open a handle to the library") + +// LibHandle represents an open handle to a library (.so) +type LibHandle struct { + Handle unsafe.Pointer + Libname string +} + +// GetHandle tries to get a handle to a library (.so), attempting to access it +// by the names specified in libs and returning the first that is successfully +// opened. Callers are responsible for closing the handler. If no library can +// be successfully opened, an error is returned. +func GetHandle(libs []string) (*LibHandle, error) { + for _, name := range libs { + libname := C.CString(name) + defer C.free(unsafe.Pointer(libname)) + handle := C.dlopen(libname, C.RTLD_LAZY) + if handle != nil { + h := &LibHandle{ + Handle: handle, + Libname: name, + } + return h, nil + } + } + return nil, ErrSoNotFound +} + +// GetSymbolPointer takes a symbol name and returns a pointer to the symbol. +func (l *LibHandle) GetSymbolPointer(symbol string) (unsafe.Pointer, error) { + sym := C.CString(symbol) + defer C.free(unsafe.Pointer(sym)) + + C.dlerror() + p := C.dlsym(l.Handle, sym) + e := C.dlerror() + if e != nil { + return nil, fmt.Errorf("error resolving symbol %q: %v", symbol, errors.New(C.GoString(e))) + } + + return p, nil +} + +// Close closes a LibHandle. +func (l *LibHandle) Close() error { + C.dlerror() + C.dlclose(l.Handle) + e := C.dlerror() + if e != nil { + return fmt.Errorf("error closing %v: %v", l.Libname, errors.New(C.GoString(e))) + } + + return nil +} 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..fb11b1179 --- /dev/null +++ b/vendor/github.com/coreos/go-systemd/v22/sdjournal/journal.go @@ -0,0 +1,1169 @@ +// 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 +// #include +// #include +// #include +// +// 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); +// } +// +// int +// my_sd_id128_get_boot(void *f, sd_id128_t *boot_id) +// { +// int(*sd_id128_get_boot)(sd_id128_t *); +// +// sd_id128_get_boot = f; +// return sd_id128_get_boot(boot_id); +// } +// +// char * +// my_sd_id128_to_string(void *f, sd_id128_t boot_id, char s[SD_ID128_STRING_MAX]) +// { +// char *(*sd_id128_to_string)(sd_id128_t, char *); +// +// sd_id128_to_string = f; +// return sd_id128_to_string(boot_id, s); +// } +// +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 Previous 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 +} + +// GetBootID get systemd boot id +func (j *Journal) GetBootID() (string, error) { + sd_id128_get_boot, err := getFunction("sd_id128_get_boot") + if err != nil { + return "", err + } + + var boot_id C.sd_id128_t + r := C.my_sd_id128_get_boot(sd_id128_get_boot, &boot_id) + if r < 0 { + return "", fmt.Errorf("failed to get boot id: %s", syscall.Errno(-r).Error()) + } + + sd_id128_to_string, err := getFunction("sd_id128_to_string") + if err != nil { + return "", err + } + + id128StringMax := C.size_t(C.SD_ID128_STRING_MAX) + c := (*C.char)(C.malloc(id128StringMax)) + defer C.free(unsafe.Pointer(c)) + C.my_sd_id128_to_string(sd_id128_to_string, boot_id, c) + + bootID := C.GoString(c) + if len(bootID) <= 0 { + return "", fmt.Errorf("get boot id %s is not valid", bootID) + } + + return bootID, 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 +} diff --git a/vendor/modules.txt b/vendor/modules.txt index 6fb3d325c..3ebe9e60c 100644 --- a/vendor/modules.txt +++ b/vendor/modules.txt @@ -156,7 +156,10 @@ github.com/containers/storage/pkg/truncindex github.com/containers/storage/pkg/unshare github.com/containers/storage/types # github.com/coreos/go-systemd/v22 v22.3.2 +## explicit github.com/coreos/go-systemd/v22/dbus +github.com/coreos/go-systemd/v22/internal/dlopen +github.com/coreos/go-systemd/v22/sdjournal # github.com/cyphar/filepath-securejoin v0.2.2 github.com/cyphar/filepath-securejoin # github.com/davecgh/go-spew v1.1.1