diff --git a/log/go.mod b/log/go.mod
new file mode 100644
index 0000000..eb0a315
--- /dev/null
+++ b/log/go.mod
@@ -0,0 +1,8 @@
+module git.blauwelle.com/go/crate/log
+
+go 1.20
+
+require (
+	git.blauwelle.com/go/crate/runtimehelper v0.1.0
+	git.blauwelle.com/go/crate/synchelper v0.1.0
+)
diff --git a/log/go.sum b/log/go.sum
new file mode 100644
index 0000000..bb0b349
--- /dev/null
+++ b/log/go.sum
@@ -0,0 +1,4 @@
+git.blauwelle.com/go/crate/runtimehelper v0.1.0 h1:qNhtnt9YmHXNHKsGRbwD3AZ3pezpOwrbmX1o9Bz532I=
+git.blauwelle.com/go/crate/runtimehelper v0.1.0/go.mod h1:yVMA0GkO9AS7iuPmalHKeWyv9en0JWj25rY1vpTuHhk=
+git.blauwelle.com/go/crate/synchelper v0.1.0 h1:4yEXpshkklaws/57P94xN5bA3NmyyKGcZqYmzd6QIK4=
+git.blauwelle.com/go/crate/synchelper v0.1.0/go.mod h1:2JkfH+7sF0Q0wiIaDOqG42ZLO5JxpcMfSoyy7db4Y2g=
diff --git a/log/log.go b/log/log.go
new file mode 100644
index 0000000..4504345
--- /dev/null
+++ b/log/log.go
@@ -0,0 +1,150 @@
+// log 实现了全局的日志处理
+//
+// 这个包里定义的函数都是对全局的 [logsdk.Logger] 对象的封装.
+// 全局的 Logger 不能重新赋值,
+// Logger 的配置方法和日志方法可以并发调用.
+
+package log
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"git.blauwelle.com/go/crate/log/logsdk"
+)
+
+type (
+	Level = logsdk.Level
+	Field = logsdk.Field
+)
+
+const (
+	LevelPanic = logsdk.LevelPanic
+	LevelFatal = logsdk.LevelFatal
+	LevelError = logsdk.LevelError
+	LevelWarn  = logsdk.LevelWarn
+	LevelInfo  = logsdk.LevelInfo
+	LevelDebug = logsdk.LevelDebug
+	LevelTrace = logsdk.LevelTrace
+)
+
+// AddCallerSkip 增加调用 [runtime.Callers] 时的 skip 参数,
+// 当通过装饰器等方式封装 Entry 导致增加调用 Entry 方法的深度时使用 AddCallerSkip 调整 skip,
+// 直接在需要日志的地方调用 Entry 的方法时不需要 AddCallerSkip.
+func AddCallerSkip(n int) logsdk.Entry {
+	return globalLogger.AddCallerSkip(n)
+}
+
+// WithField 增加1组键值对
+func WithField(key string, value any) logsdk.Entry {
+	return globalLogger.WithField(key, value)
+}
+
+// WithFields 增加键值对
+func WithFields(fields ...logsdk.Field) logsdk.Entry {
+	return globalLogger.WithFields(fields...)
+}
+
+// WithTime 设置日志的时间,
+// Entry 默认使用调用 Log 等最终方法的时间作为日志的时间.
+func WithTime(t time.Time) logsdk.Entry {
+	return globalLogger.WithTime(t)
+}
+
+// WithReportCaller 设置 [logsdk.Entry] 是否收集调用记录
+func WithReportCaller(reportCaller bool) logsdk.Entry {
+	return globalLogger.WithReportCaller(reportCaller)
+}
+
+// WithReportStack 设置 [logsdk.Entry] 是否收集调用栈
+func WithReportStack(reportStack bool) logsdk.Entry {
+	return globalLogger.WithReportStack(reportStack)
+}
+
+// Log 输出日志
+func Log(ctx context.Context, level Level, args ...any) {
+	globalLogger.AddCallerSkip(1).Log(ctx, level, fmt.Sprint(args...))
+}
+
+// Trace 输出 LevelTrace 等级的日志
+func Trace(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Trace(ctx, args...)
+}
+
+// Debug 输出 LevelDebug 等级的日志
+func Debug(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Debug(ctx, args...)
+}
+
+// Info 输出 LevelInfo 等级的日志
+func Info(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Info(ctx, args...)
+}
+
+// Warn 输出 LevelWarn 等级的日志
+func Warn(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Warn(ctx, args...)
+}
+
+// Error 输出 LevelError 等级的日志
+func Error(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Error(ctx, args...)
+}
+
+// Fatal 输出 LevelFatal 等级的日志并调用 Logger.Exit
+func Fatal(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Fatal(ctx, args...)
+}
+
+// Panic 输出 LevelPanic 等级的日志后执行 panic,
+// 即使 Logger 日志等级高于 LevelPanic 也会 panic.
+func Panic(ctx context.Context, args ...any) {
+	globalLogger.AddCallerSkip(1).Panic(ctx, args...)
+}
+
+// Logf 格式化输出日志
+func Logf(ctx context.Context, level Level, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Logf(ctx, level, format, args...)
+}
+
+// Tracef 格式化输出 LevelTrace 等级的日志
+func Tracef(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Tracef(ctx, format, args...)
+}
+
+// Debugf 格式化输出 LevelDebug 等级的日志
+func Debugf(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Debugf(ctx, format, args...)
+}
+
+// Infof 格式化输出 LevelInfo 等级的日志
+func Infof(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Infof(ctx, format, args...)
+}
+
+// Warnf 格式化输出 LevelWarn 等级的日志
+func Warnf(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Warnf(ctx, format, args...)
+}
+
+// Errorf 格式化输出 LevelError 等级的日志
+func Errorf(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Errorf(ctx, format, args...)
+}
+
+// Fatalf 格式化输出 LevelFatal 等级的日志并调用 Logger.Exit
+func Fatalf(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Fatalf(ctx, format, args...)
+}
+
+// Panicf 格式化输出 LevelPanic 等级的日志
+func Panicf(ctx context.Context, format string, args ...any) {
+	globalLogger.AddCallerSkip(1).Panicf(ctx, format, args...)
+}
+
+// Logger 返回全局 logger, 通常用来在程序启动时对全局 logger 进行配置,
+// 业务代码处理日志时直接使用这个包里定义的日志函数.
+func Logger() *logsdk.Logger {
+	return globalLogger
+}
diff --git a/log/logsdk/entry.go b/log/logsdk/entry.go
new file mode 100644
index 0000000..c4c3caf
--- /dev/null
+++ b/log/logsdk/entry.go
@@ -0,0 +1,220 @@
+package logsdk
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"git.blauwelle.com/go/crate/runtimehelper"
+)
+
+// Entry 包含日志所需的全部中间信息并负责输出日志
+type Entry struct {
+	logger            *Logger
+	time              time.Time
+	fields            []Field
+	callerSkip        int
+	reportCaller      bool
+	isReportCallerSet bool
+	reportStack       bool
+	isReportStackSet  bool
+	initialized       bool
+}
+
+func (entry Entry) copy() Entry {
+	if entry.initialized {
+		return entry
+	}
+	return entry.logger.newEntry()
+}
+
+// AddCallerSkip 增加调用 [runtime.Callers] 时的 skip 参数,
+// 当通过装饰器等方式封装 Entry 导致增加调用 Entry 方法的深度时使用 AddCallerSkip 调整 skip,
+// 直接在需要日志的地方调用 Entry 的方法时不需要 AddCallerSkip.
+func (entry Entry) AddCallerSkip(n int) Entry {
+	newEntry := entry.copy()
+	newEntry.callerSkip += n
+	return newEntry
+}
+
+// WithField 增加1组键值对
+func (entry Entry) WithField(key string, value any) Entry {
+	return entry.WithFields(Field{Key: key, Value: value})
+}
+
+// WithFields 增加键值对
+func (entry Entry) WithFields(fields ...Field) Entry {
+	newEntry := entry.copy()
+	newEntry.fields = make([]Field, len(entry.fields)+len(fields))
+	copy(newEntry.fields, entry.fields)
+	copy(newEntry.fields, fields)
+	return newEntry
+}
+
+// WithTime 设置日志的时间,
+// Entry 默认使用调用 Log 等最终方法的时间作为日志的时间.
+func (entry Entry) WithTime(t time.Time) Entry {
+	newEntry := entry.copy()
+	newEntry.time = t
+	return newEntry
+}
+
+// GetReportCaller 获取是否收集调用记录,
+// 默认使用 Logger 上的对应配置.
+func (entry Entry) GetReportCaller() bool {
+	if entry.isReportCallerSet {
+		return entry.reportCaller
+	}
+	return entry.logger.GetReportCaller()
+}
+
+// WithReportCaller 设置是否收集调用记录
+func (entry Entry) WithReportCaller(reportCaller bool) Entry {
+	newEntry := entry.copy()
+	newEntry.reportCaller = reportCaller
+	newEntry.isReportCallerSet = true
+	return newEntry
+}
+
+// GetReportStack 获取是否收集调用栈,
+// 默认使用 Logger 上的对应配置.
+func (entry Entry) GetReportStack() bool {
+	if entry.isReportStackSet {
+		return entry.reportStack
+	}
+	return entry.logger.GetReportStack()
+}
+
+// WithReportStack 设置是否收集调用栈
+func (entry Entry) WithReportStack(reportStack bool) Entry {
+	newEntry := entry.copy()
+	newEntry.reportStack = reportStack
+	newEntry.isReportStackSet = true
+	return newEntry
+}
+
+// Log 输出日志
+func (entry Entry) Log(ctx context.Context, level Level, args ...any) {
+	entry.log(ctx, level, fmt.Sprint(args...))
+}
+
+// Trace 输出 LevelTrace 等级的日志
+func (entry Entry) Trace(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelTrace, fmt.Sprint(args...))
+}
+
+// Debug 输出 LevelDebug 等级的日志
+func (entry Entry) Debug(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelDebug, fmt.Sprint(args...))
+}
+
+// Info 输出 LevelInfo 等级的日志
+func (entry Entry) Info(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelInfo, fmt.Sprint(args...))
+}
+
+// Warn 输出 LevelWarn 等级的日志
+func (entry Entry) Warn(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelWarn, fmt.Sprint(args...))
+}
+
+// Error 输出 LevelError 等级的日志
+func (entry Entry) Error(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelError, fmt.Sprint(args...))
+}
+
+// Fatal 输出 LevelFatal 等级的日志并调用 Logger.Exit
+func (entry Entry) Fatal(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelFatal, fmt.Sprint(args...))
+	entry.logger.Exit(1)
+}
+
+// Panic 输出 LevelPanic 等级的日志后执行 panic,
+// 即使 Logger 日志等级高于 LevelPanic 也会 panic.
+func (entry Entry) Panic(ctx context.Context, args ...any) {
+	entry.log(ctx, LevelPanic, fmt.Sprint(args...))
+}
+
+// Logf 格式化输出日志
+func (entry Entry) Logf(ctx context.Context, level Level, format string, args ...any) {
+	entry.log(ctx, level, fmt.Sprintf(format, args...))
+}
+
+// Tracef 格式化输出 LevelTrace 等级的日志
+func (entry Entry) Tracef(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelTrace, fmt.Sprintf(format, args...))
+}
+
+// Debugf 格式化输出 LevelDebug 等级的日志
+func (entry Entry) Debugf(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelDebug, fmt.Sprintf(format, args...))
+}
+
+// Infof 格式化输出 LevelInfo 等级的日志
+func (entry Entry) Infof(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelInfo, fmt.Sprintf(format, args...))
+}
+
+// Warnf 格式化输出 LevelWarn 等级的日志
+func (entry Entry) Warnf(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelWarn, fmt.Sprintf(format, args...))
+}
+
+// Errorf 格式化输出 LevelError 等级的日志
+func (entry Entry) Errorf(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelError, fmt.Sprintf(format, args...))
+}
+
+// Fatalf 格式化输出 LevelFatal 等级的日志并调用 Logger.Exit
+func (entry Entry) Fatalf(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelFatal, fmt.Sprintf(format, args...))
+	entry.logger.Exit(1)
+}
+
+// Panicf 格式化输出 LevelPanic 等级的日志
+// 即使 Logger 日志等级高于 LevelPanic 也会 panic.
+func (entry Entry) Panicf(ctx context.Context, format string, args ...any) {
+	entry.log(ctx, LevelPanic, fmt.Sprintf(format, args...))
+}
+
+func (entry Entry) log(ctx context.Context, level Level, message string) {
+	newEntry := entry.copy()
+	defer func() {
+		if level == LevelPanic {
+			panic(message)
+		}
+	}()
+	if newEntry.logger.GetLevel() < level {
+		return
+	}
+	readonlyEntry := ReadonlyEntry{
+		Context: ctx,
+		Fields:  newEntry.fields,
+		Message: message,
+		Time:    newEntry.time,
+		Level:   level,
+	}
+	if readonlyEntry.Time.IsZero() {
+		readonlyEntry.Time = time.Now()
+	}
+	if newEntry.GetReportCaller() {
+		readonlyEntry.Caller = runtimehelper.Caller(newEntry.callerSkip)
+	}
+	if newEntry.GetReportStack() {
+		readonlyEntry.Stack = runtimehelper.Stack(newEntry.callerSkip, 32)
+	}
+	for _, processor := range newEntry.logger.getLevelProcessors(level) {
+		processor.Process(readonlyEntry)
+	}
+}
+
+// ReadonlyEntry 是日志系统收集到1条日志记录
+type ReadonlyEntry struct {
+	Context context.Context `json:"-"`
+	Caller  runtimehelper.Frame
+	Stack   []runtimehelper.Frame
+	Time    time.Time
+	Message string
+	Fields  []Field
+	Level   Level
+}
diff --git a/log/logsdk/field.go b/log/logsdk/field.go
new file mode 100644
index 0000000..fe379ff
--- /dev/null
+++ b/log/logsdk/field.go
@@ -0,0 +1,7 @@
+package logsdk
+
+// Field 是日志记录中的键值对
+type Field struct {
+	Value any    `json:"v"`
+	Key   string `json:"k"`
+}
diff --git a/log/logsdk/jsonlog/processor.go b/log/logsdk/jsonlog/processor.go
new file mode 100644
index 0000000..3da6e57
--- /dev/null
+++ b/log/logsdk/jsonlog/processor.go
@@ -0,0 +1,166 @@
+package jsonlog
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"git.blauwelle.com/go/crate/log/logsdk"
+	"git.blauwelle.com/go/crate/runtimehelper"
+	"git.blauwelle.com/go/crate/synchelper"
+)
+
+var _ logsdk.EntryProcessor = &Processor{}
+
+// New 返回日志处理对象,
+// 返回的对象是 [logsdk.EntryProcessor].
+func New(opts ...Option) *Processor {
+	cfg := defaultConfig()
+	for _, opt := range opts {
+		opt.apply(cfg)
+	}
+	return &Processor{
+		bufferPool:        cfg.pool,
+		output:            cfg.output,
+		timeFormat:        cfg.timestampFormat,
+		disableTime:       cfg.disableTime,
+		disableHTMLEscape: cfg.disableHTMLEscape,
+		prettyPrint:       cfg.prettyPrint,
+	}
+}
+
+// Processor 日志处理对象, 把日志处理成 JSON.
+type Processor struct {
+	bufferPool        synchelper.BytesBufferPool
+	output            io.Writer
+	timeFormat        string
+	disableTime       bool
+	disableHTMLEscape bool
+	prettyPrint       bool
+}
+
+// Process 处理日志
+func (processor *Processor) Process(entry logsdk.ReadonlyEntry) {
+	m := Entry{
+		Stack:   entry.Stack,
+		Fields:  entry.Fields,
+		Level:   entry.Level,
+		Message: entry.Message,
+	}
+	if !processor.disableTime {
+		m.Time = entry.Time.Format(processor.timeFormat) // 1次分配
+	}
+	if entry.Caller.IsValid() {
+		// 1次分配
+		// 直接取 &entry.Caller 会增加堆内存分配
+		m.Caller = &runtimehelper.Frame{
+			Function: entry.Caller.Function,
+			File:     entry.Caller.File,
+			Line:     entry.Caller.Line,
+		}
+	}
+
+	buf := processor.bufferPool.Get()
+	buf.Reset()
+	defer processor.bufferPool.Put(buf)
+
+	encoder := json.NewEncoder(buf)
+	if processor.prettyPrint {
+		encoder.SetIndent("", "  ")
+	}
+	encoder.SetEscapeHTML(!processor.disableHTMLEscape)
+
+	// Encode 2次分配
+	if err := encoder.Encode(m); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "JSON processor cannot encode log %#v: %s\n", m, err.Error())
+	}
+
+	if _, err := buf.WriteTo(processor.output); err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "JSON processor cannot write log: %s\n", err.Error())
+	}
+}
+
+// Option 配置日志处理对象
+type Option interface {
+	apply(cfg *config)
+}
+
+// WithBufferPool 配置缓冲池
+func WithBufferPool(pool synchelper.BytesBufferPool) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.pool = pool
+	})
+}
+
+// WithOutput 配置输出
+func WithOutput(w io.Writer) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.output = w
+	})
+}
+
+// WithTimeFormat 配置时间格式
+func WithTimeFormat(format string) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.timestampFormat = format
+	})
+}
+
+// WithDisableTime 配置仅用时间输出
+func WithDisableTime(disable bool) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.disableTime = disable
+	})
+}
+
+// WithDisableHTMLEscape 配置禁止 HTML 转义
+func WithDisableHTMLEscape(disable bool) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.disableHTMLEscape = disable
+	})
+}
+
+// WithPrettyPrint 配置 JSON 多行缩进输出
+func WithPrettyPrint(pretty bool) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.prettyPrint = pretty
+	})
+}
+
+// Entry 被用来 JSON 序列化
+type Entry struct {
+	Message string                `json:"msg"`
+	Time    string                `json:"time,omitempty"`
+	Caller  *runtimehelper.Frame  `json:"caller,omitempty"`
+	Stack   []runtimehelper.Frame `json:"stack,omitempty"`
+	Fields  []logsdk.Field        `json:"fields,omitempty"`
+	Level   logsdk.Level          `json:"level"`
+}
+
+func defaultConfig() *config {
+	return &config{
+		pool:              synchelper.NewBytesBufferPool(512, 2048),
+		output:            synchelper.NewSyncWriter(os.Stderr),
+		timestampFormat:   time.RFC3339Nano,
+		disableTime:       false,
+		disableHTMLEscape: false,
+		prettyPrint:       false,
+	}
+}
+
+type config struct {
+	pool              synchelper.BytesBufferPool
+	output            io.Writer
+	timestampFormat   string
+	disableTime       bool
+	disableHTMLEscape bool
+	prettyPrint       bool
+}
+
+type optionFunc func(cfg *config)
+
+func (fn optionFunc) apply(cfg *config) {
+	fn(cfg)
+}
diff --git a/log/logsdk/level.go b/log/logsdk/level.go
new file mode 100644
index 0000000..514fb67
--- /dev/null
+++ b/log/logsdk/level.go
@@ -0,0 +1,74 @@
+package logsdk
+
+import "fmt"
+
+// Level 日志等级
+type Level int
+
+func (level Level) String() string {
+	if b, err := level.MarshalText(); err == nil {
+		return string(b)
+	}
+	return "unknown"
+}
+
+func (level Level) MarshalText() ([]byte, error) {
+	switch level {
+	case LevelPanic:
+		return []byte(LevelPanicValue), nil
+	case LevelFatal:
+		return []byte(LevelFatalValue), nil
+	case LevelError:
+		return []byte(LevelErrorValue), nil
+	case LevelWarn:
+		return []byte(LevelWarnValue), nil
+	case LevelInfo:
+		return []byte(LevelInfoValue), nil
+	case LevelDebug:
+		return []byte(LevelDebugValue), nil
+	case LevelTrace:
+		return []byte(LevelTraceValue), nil
+	}
+	return nil, fmt.Errorf("not a valid log level %d", level)
+}
+
+const (
+	// LevelCount 日志等级的个数
+	LevelCount = 7
+
+	// LevelOffset 是把 LevelInfo 等级的日志值偏移到零值的偏移量
+	LevelOffset = 4
+)
+
+const (
+	// LevelDisabled 表示不处理任何等级的日志,
+	// 其他日志等级的值越小表示日志严重程度越高.
+	LevelDisabled Level = iota - LevelOffset - 1
+	LevelPanic
+	LevelFatal
+	LevelError
+	LevelWarn
+	LevelInfo
+	LevelDebug
+	LevelTrace
+)
+
+const (
+	LevelPanicValue = "panic"
+	LevelFatalValue = "fatal"
+	LevelErrorValue = "error"
+	LevelWarnValue  = "warn"
+	LevelInfoValue  = "info"
+	LevelDebugValue = "debug"
+	LevelTraceValue = "trace"
+)
+
+var AllLevels = []Level{
+	LevelPanic,
+	LevelFatal,
+	LevelError,
+	LevelWarn,
+	LevelInfo,
+	LevelDebug,
+	LevelTrace,
+}
diff --git a/log/logsdk/logger.go b/log/logsdk/logger.go
new file mode 100644
index 0000000..9ed981a
--- /dev/null
+++ b/log/logsdk/logger.go
@@ -0,0 +1,129 @@
+package logsdk
+
+import (
+	"os"
+	"sync"
+	"sync/atomic"
+)
+
+// New 返回初始未经过参数调整的 Logger
+func New() *Logger {
+	logger := &Logger{}
+	logger.entry.logger = logger
+	return logger
+}
+
+// entry 仅被用来嵌入 Logger
+type entry = Entry
+
+// Logger 中保存了日志所需的全局配置,
+// 使用 Logger 处理日志.
+type Logger struct {
+	exit            func(code int)  // protected by lock
+	levelProcessors levelProcessors // protected by lock
+	entry
+	lock         sync.RWMutex
+	level        atomic.Int32
+	callerSkip   atomic.Int32
+	reportCaller atomic.Bool
+	reportStack  atomic.Bool
+}
+
+// AddProcessor 把日志处理器增加到 Logger
+func (logger *Logger) AddProcessor(levels []Level, processor EntryProcessor) {
+	logger.lock.Lock()
+	for _, level := range levels {
+		logger.levelProcessors[level+LevelOffset] = append(logger.levelProcessors[level+LevelOffset], processor)
+	}
+	logger.lock.Unlock()
+}
+
+// GetLevel 返回日志系统的等级, 严重程度低于返回等级的日志不会被处理.
+func (logger *Logger) GetLevel() Level {
+	return Level(logger.level.Load())
+}
+
+// SetLevel 设置日志系统的等级
+func (logger *Logger) SetLevel(level Level) {
+	logger.level.Store(int32(level))
+}
+
+// GetCallerSkip 获取调用 [runtime.Callers] 时的 skip 参数,
+// skip 已经被偏移到从调用 Logger 相关方法处获取调用信息.
+// 0 表示从调用 Logger 相关方法处获取调用信息.
+func (logger *Logger) GetCallerSkip() int {
+	return int(logger.callerSkip.Load())
+}
+
+// SetCallerSkip 设置调用 [runtime.Callers] 时的 skip 参数,
+// skip 已经被偏移到从调用 Logger 相关方法处获取调用信息.
+// 0 表示从调用 Logger 相关方法处获取调用信息.
+func (logger *Logger) SetCallerSkip(callerSkip int) {
+	logger.callerSkip.Store(int32(callerSkip))
+}
+
+// GetReportCaller 返回是否收集调用信息
+func (logger *Logger) GetReportCaller() bool {
+	return logger.reportCaller.Load()
+}
+
+// SetReportCaller 设置是否收集调用信息
+func (logger *Logger) SetReportCaller(reportCaller bool) {
+	logger.reportCaller.Store(reportCaller)
+}
+
+// GetReportStack 返回是否收集调用栈信息
+func (logger *Logger) GetReportStack() bool {
+	return logger.reportStack.Load()
+}
+
+// SetReportStack 设置是否收集调用栈信息
+func (logger *Logger) SetReportStack(reportStack bool) {
+	logger.reportStack.Store(reportStack)
+}
+
+// Reset 把 Logger 重置到初始状态
+func (logger *Logger) Reset() {
+	logger.lock.Lock()
+	logger.exit = nil
+	logger.levelProcessors = levelProcessors{}
+	logger.lock.Unlock()
+
+	logger.SetLevel(LevelInfo)
+	logger.SetCallerSkip(0)
+	logger.SetReportCaller(false)
+	logger.SetReportStack(false)
+}
+
+// Exit 退出程序, 执行的具体过程可以通过 SetExit 指定
+func (logger *Logger) Exit(code int) {
+	logger.lock.RLock()
+	defer logger.lock.RUnlock()
+	if logger.exit == nil {
+		os.Exit(code)
+	}
+	logger.exit(code)
+}
+
+// SetExit 指定退出程序时执行的函数
+func (logger *Logger) SetExit(fn func(code int)) {
+	logger.lock.Lock()
+	logger.exit = fn
+	logger.lock.Unlock()
+}
+
+func (logger *Logger) getLevelProcessors(level Level) []EntryProcessor {
+	logger.lock.RLock()
+	defer logger.lock.RUnlock()
+	return logger.levelProcessors[level+LevelOffset]
+}
+
+func (logger *Logger) newEntry() Entry {
+	return Entry{
+		logger:       logger,
+		callerSkip:   logger.GetCallerSkip() + 2,
+		reportCaller: logger.GetReportCaller(),
+		reportStack:  logger.GetReportStack(),
+		initialized:  true,
+	}
+}
diff --git a/log/logsdk/processor.go b/log/logsdk/processor.go
new file mode 100644
index 0000000..4b85d85
--- /dev/null
+++ b/log/logsdk/processor.go
@@ -0,0 +1,8 @@
+package logsdk
+
+// EntryProcessor 处理日志记录
+type EntryProcessor interface {
+	Process(entry ReadonlyEntry)
+}
+
+type levelProcessors [LevelCount][]EntryProcessor
diff --git a/log/state.go b/log/state.go
new file mode 100644
index 0000000..0f4cd0e
--- /dev/null
+++ b/log/state.go
@@ -0,0 +1,8 @@
+package log
+
+import (
+	"git.blauwelle.com/go/crate/log/logsdk"
+)
+
+// globalLogger 不能重新赋值
+var globalLogger = logsdk.New()