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-rw-r--r--log/CONTRIBUTORS11
-rw-r--r--log/LICENSE13
-rw-r--r--log/README.md77
-rw-r--r--log/README_ETHEREUM.md4
-rw-r--r--log/doc.go333
-rw-r--r--log/format.go279
-rw-r--r--log/handler.go356
-rw-r--r--log/handler_go13.go26
-rw-r--r--log/handler_go14.go23
-rw-r--r--log/logger.go208
-rw-r--r--log/root.go67
-rw-r--r--log/syslog.go55
-rw-r--r--log/term/LICENSE21
-rw-r--r--log/term/terminal_appengine.go13
-rw-r--r--log/term/terminal_darwin.go13
-rw-r--r--log/term/terminal_freebsd.go18
-rw-r--r--log/term/terminal_linux.go14
-rw-r--r--log/term/terminal_netbsd.go7
-rw-r--r--log/term/terminal_notwindows.go20
-rw-r--r--log/term/terminal_openbsd.go7
-rw-r--r--log/term/terminal_solaris.go9
-rw-r--r--log/term/terminal_windows.go26
22 files changed, 1600 insertions, 0 deletions
diff --git a/log/CONTRIBUTORS b/log/CONTRIBUTORS
new file mode 100644
index 000000000..a0866713b
--- /dev/null
+++ b/log/CONTRIBUTORS
@@ -0,0 +1,11 @@
+Contributors to log15:
+
+- Aaron L
+- Alan Shreve
+- Chris Hines
+- Ciaran Downey
+- Dmitry Chestnykh
+- Evan Shaw
+- Péter Szilágyi
+- Trevor Gattis
+- Vincent Vanackere
diff --git a/log/LICENSE b/log/LICENSE
new file mode 100644
index 000000000..5f0d1fb6a
--- /dev/null
+++ b/log/LICENSE
@@ -0,0 +1,13 @@
+Copyright 2014 Alan Shreve
+
+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.
diff --git a/log/README.md b/log/README.md
new file mode 100644
index 000000000..0951b21cb
--- /dev/null
+++ b/log/README.md
@@ -0,0 +1,77 @@
+![obligatory xkcd](http://imgs.xkcd.com/comics/standards.png)
+
+# log15 [![godoc reference](https://godoc.org/github.com/inconshreveable/log15?status.png)](https://godoc.org/github.com/inconshreveable/log15) [![Build Status](https://travis-ci.org/inconshreveable/log15.svg?branch=master)](https://travis-ci.org/inconshreveable/log15)
+
+Package log15 provides an opinionated, simple toolkit for best-practice logging in Go (golang) that is both human and machine readable. It is modeled after the Go standard library's [`io`](http://golang.org/pkg/io/) and [`net/http`](http://golang.org/pkg/net/http/) packages and is an alternative to the standard library's [`log`](http://golang.org/pkg/log/) package.
+
+## Features
+- A simple, easy-to-understand API
+- Promotes structured logging by encouraging use of key/value pairs
+- Child loggers which inherit and add their own private context
+- Lazy evaluation of expensive operations
+- Simple Handler interface allowing for construction of flexible, custom logging configurations with a tiny API.
+- Color terminal support
+- Built-in support for logging to files, streams, syslog, and the network
+- Support for forking records to multiple handlers, buffering records for output, failing over from failed handler writes, + more
+
+## Versioning
+The API of the master branch of log15 should always be considered unstable. If you want to rely on a stable API,
+you must vendor the library.
+
+## Importing
+
+```go
+import log "github.com/inconshreveable/log15"
+```
+
+## Examples
+
+```go
+// all loggers can have key/value context
+srvlog := log.New("module", "app/server")
+
+// all log messages can have key/value context
+srvlog.Warn("abnormal conn rate", "rate", curRate, "low", lowRate, "high", highRate)
+
+// child loggers with inherited context
+connlog := srvlog.New("raddr", c.RemoteAddr())
+connlog.Info("connection open")
+
+// lazy evaluation
+connlog.Debug("ping remote", "latency", log.Lazy{pingRemote})
+
+// flexible configuration
+srvlog.SetHandler(log.MultiHandler(
+ log.StreamHandler(os.Stderr, log.LogfmtFormat()),
+ log.LvlFilterHandler(
+ log.LvlError,
+ log.Must.FileHandler("errors.json", log.JsonFormat()))))
+```
+
+Will result in output that looks like this:
+
+```
+WARN[06-17|21:58:10] abnormal conn rate module=app/server rate=0.500 low=0.100 high=0.800
+INFO[06-17|21:58:10] connection open module=app/server raddr=10.0.0.1
+```
+
+## Breaking API Changes
+The following commits broke API stability. This reference is intended to help you understand the consequences of updating to a newer version
+of log15.
+
+- 57a084d014d4150152b19e4e531399a7145d1540 - Added a `Get()` method to the `Logger` interface to retrieve the current handler
+- 93404652ee366648fa622b64d1e2b67d75a3094a - `Record` field `Call` changed to `stack.Call` with switch to `github.com/go-stack/stack`
+- a5e7613673c73281f58e15a87d2cf0cf111e8152 - Restored `syslog.Priority` argument to the `SyslogXxx` handler constructors
+
+## FAQ
+
+### The varargs style is brittle and error prone! Can I have type safety please?
+Yes. Use `log.Ctx`:
+
+```go
+srvlog := log.New(log.Ctx{"module": "app/server"})
+srvlog.Warn("abnormal conn rate", log.Ctx{"rate": curRate, "low": lowRate, "high": highRate})
+```
+
+## License
+Apache
diff --git a/log/README_ETHEREUM.md b/log/README_ETHEREUM.md
new file mode 100644
index 000000000..6a0b0141b
--- /dev/null
+++ b/log/README_ETHEREUM.md
@@ -0,0 +1,4 @@
+This package is a fork of https://github.com/inconshreveable/log15, with some
+minor modifications required by the go-ethereum codebase:
+
+ * Support for log level `trace`
diff --git a/log/doc.go b/log/doc.go
new file mode 100644
index 000000000..83ad8c54f
--- /dev/null
+++ b/log/doc.go
@@ -0,0 +1,333 @@
+/*
+Package log15 provides an opinionated, simple toolkit for best-practice logging that is
+both human and machine readable. It is modeled after the standard library's io and net/http
+packages.
+
+This package enforces you to only log key/value pairs. Keys must be strings. Values may be
+any type that you like. The default output format is logfmt, but you may also choose to use
+JSON instead if that suits you. Here's how you log:
+
+ log.Info("page accessed", "path", r.URL.Path, "user_id", user.id)
+
+This will output a line that looks like:
+
+ lvl=info t=2014-05-02T16:07:23-0700 msg="page accessed" path=/org/71/profile user_id=9
+
+Getting Started
+
+To get started, you'll want to import the library:
+
+ import log "github.com/inconshreveable/log15"
+
+
+Now you're ready to start logging:
+
+ func main() {
+ log.Info("Program starting", "args", os.Args())
+ }
+
+
+Convention
+
+Because recording a human-meaningful message is common and good practice, the first argument to every
+logging method is the value to the *implicit* key 'msg'.
+
+Additionally, the level you choose for a message will be automatically added with the key 'lvl', and so
+will the current timestamp with key 't'.
+
+You may supply any additional context as a set of key/value pairs to the logging function. log15 allows
+you to favor terseness, ordering, and speed over safety. This is a reasonable tradeoff for
+logging functions. You don't need to explicitly state keys/values, log15 understands that they alternate
+in the variadic argument list:
+
+ log.Warn("size out of bounds", "low", lowBound, "high", highBound, "val", val)
+
+If you really do favor your type-safety, you may choose to pass a log.Ctx instead:
+
+ log.Warn("size out of bounds", log.Ctx{"low": lowBound, "high": highBound, "val": val})
+
+
+Context loggers
+
+Frequently, you want to add context to a logger so that you can track actions associated with it. An http
+request is a good example. You can easily create new loggers that have context that is automatically included
+with each log line:
+
+ requestlogger := log.New("path", r.URL.Path)
+
+ // later
+ requestlogger.Debug("db txn commit", "duration", txnTimer.Finish())
+
+This will output a log line that includes the path context that is attached to the logger:
+
+ lvl=dbug t=2014-05-02T16:07:23-0700 path=/repo/12/add_hook msg="db txn commit" duration=0.12
+
+
+Handlers
+
+The Handler interface defines where log lines are printed to and how they are formated. Handler is a
+single interface that is inspired by net/http's handler interface:
+
+ type Handler interface {
+ Log(r *Record) error
+ }
+
+
+Handlers can filter records, format them, or dispatch to multiple other Handlers.
+This package implements a number of Handlers for common logging patterns that are
+easily composed to create flexible, custom logging structures.
+
+Here's an example handler that prints logfmt output to Stdout:
+
+ handler := log.StreamHandler(os.Stdout, log.LogfmtFormat())
+
+Here's an example handler that defers to two other handlers. One handler only prints records
+from the rpc package in logfmt to standard out. The other prints records at Error level
+or above in JSON formatted output to the file /var/log/service.json
+
+ handler := log.MultiHandler(
+ log.LvlFilterHandler(log.LvlError, log.Must.FileHandler("/var/log/service.json", log.JsonFormat())),
+ log.MatchFilterHandler("pkg", "app/rpc" log.StdoutHandler())
+ )
+
+Logging File Names and Line Numbers
+
+This package implements three Handlers that add debugging information to the
+context, CallerFileHandler, CallerFuncHandler and CallerStackHandler. Here's
+an example that adds the source file and line number of each logging call to
+the context.
+
+ h := log.CallerFileHandler(log.StdoutHandler)
+ log.Root().SetHandler(h)
+ ...
+ log.Error("open file", "err", err)
+
+This will output a line that looks like:
+
+ lvl=eror t=2014-05-02T16:07:23-0700 msg="open file" err="file not found" caller=data.go:42
+
+Here's an example that logs the call stack rather than just the call site.
+
+ h := log.CallerStackHandler("%+v", log.StdoutHandler)
+ log.Root().SetHandler(h)
+ ...
+ log.Error("open file", "err", err)
+
+This will output a line that looks like:
+
+ lvl=eror t=2014-05-02T16:07:23-0700 msg="open file" err="file not found" stack="[pkg/data.go:42 pkg/cmd/main.go]"
+
+The "%+v" format instructs the handler to include the path of the source file
+relative to the compile time GOPATH. The github.com/go-stack/stack package
+documents the full list of formatting verbs and modifiers available.
+
+Custom Handlers
+
+The Handler interface is so simple that it's also trivial to write your own. Let's create an
+example handler which tries to write to one handler, but if that fails it falls back to
+writing to another handler and includes the error that it encountered when trying to write
+to the primary. This might be useful when trying to log over a network socket, but if that
+fails you want to log those records to a file on disk.
+
+ type BackupHandler struct {
+ Primary Handler
+ Secondary Handler
+ }
+
+ func (h *BackupHandler) Log (r *Record) error {
+ err := h.Primary.Log(r)
+ if err != nil {
+ r.Ctx = append(ctx, "primary_err", err)
+ return h.Secondary.Log(r)
+ }
+ return nil
+ }
+
+This pattern is so useful that a generic version that handles an arbitrary number of Handlers
+is included as part of this library called FailoverHandler.
+
+Logging Expensive Operations
+
+Sometimes, you want to log values that are extremely expensive to compute, but you don't want to pay
+the price of computing them if you haven't turned up your logging level to a high level of detail.
+
+This package provides a simple type to annotate a logging operation that you want to be evaluated
+lazily, just when it is about to be logged, so that it would not be evaluated if an upstream Handler
+filters it out. Just wrap any function which takes no arguments with the log.Lazy type. For example:
+
+ func factorRSAKey() (factors []int) {
+ // return the factors of a very large number
+ }
+
+ log.Debug("factors", log.Lazy{factorRSAKey})
+
+If this message is not logged for any reason (like logging at the Error level), then
+factorRSAKey is never evaluated.
+
+Dynamic context values
+
+The same log.Lazy mechanism can be used to attach context to a logger which you want to be
+evaluated when the message is logged, but not when the logger is created. For example, let's imagine
+a game where you have Player objects:
+
+ type Player struct {
+ name string
+ alive bool
+ log.Logger
+ }
+
+You always want to log a player's name and whether they're alive or dead, so when you create the player
+object, you might do:
+
+ p := &Player{name: name, alive: true}
+ p.Logger = log.New("name", p.name, "alive", p.alive)
+
+Only now, even after a player has died, the logger will still report they are alive because the logging
+context is evaluated when the logger was created. By using the Lazy wrapper, we can defer the evaluation
+of whether the player is alive or not to each log message, so that the log records will reflect the player's
+current state no matter when the log message is written:
+
+ p := &Player{name: name, alive: true}
+ isAlive := func() bool { return p.alive }
+ player.Logger = log.New("name", p.name, "alive", log.Lazy{isAlive})
+
+Terminal Format
+
+If log15 detects that stdout is a terminal, it will configure the default
+handler for it (which is log.StdoutHandler) to use TerminalFormat. This format
+logs records nicely for your terminal, including color-coded output based
+on log level.
+
+Error Handling
+
+Becasuse log15 allows you to step around the type system, there are a few ways you can specify
+invalid arguments to the logging functions. You could, for example, wrap something that is not
+a zero-argument function with log.Lazy or pass a context key that is not a string. Since logging libraries
+are typically the mechanism by which errors are reported, it would be onerous for the logging functions
+to return errors. Instead, log15 handles errors by making these guarantees to you:
+
+- Any log record containing an error will still be printed with the error explained to you as part of the log record.
+
+- Any log record containing an error will include the context key LOG15_ERROR, enabling you to easily
+(and if you like, automatically) detect if any of your logging calls are passing bad values.
+
+Understanding this, you might wonder why the Handler interface can return an error value in its Log method. Handlers
+are encouraged to return errors only if they fail to write their log records out to an external source like if the
+syslog daemon is not responding. This allows the construction of useful handlers which cope with those failures
+like the FailoverHandler.
+
+Library Use
+
+log15 is intended to be useful for library authors as a way to provide configurable logging to
+users of their library. Best practice for use in a library is to always disable all output for your logger
+by default and to provide a public Logger instance that consumers of your library can configure. Like so:
+
+ package yourlib
+
+ import "github.com/inconshreveable/log15"
+
+ var Log = log.New()
+
+ func init() {
+ Log.SetHandler(log.DiscardHandler())
+ }
+
+Users of your library may then enable it if they like:
+
+ import "github.com/inconshreveable/log15"
+ import "example.com/yourlib"
+
+ func main() {
+ handler := // custom handler setup
+ yourlib.Log.SetHandler(handler)
+ }
+
+Best practices attaching logger context
+
+The ability to attach context to a logger is a powerful one. Where should you do it and why?
+I favor embedding a Logger directly into any persistent object in my application and adding
+unique, tracing context keys to it. For instance, imagine I am writing a web browser:
+
+ type Tab struct {
+ url string
+ render *RenderingContext
+ // ...
+
+ Logger
+ }
+
+ func NewTab(url string) *Tab {
+ return &Tab {
+ // ...
+ url: url,
+
+ Logger: log.New("url", url),
+ }
+ }
+
+When a new tab is created, I assign a logger to it with the url of
+the tab as context so it can easily be traced through the logs.
+Now, whenever we perform any operation with the tab, we'll log with its
+embedded logger and it will include the tab title automatically:
+
+ tab.Debug("moved position", "idx", tab.idx)
+
+There's only one problem. What if the tab url changes? We could
+use log.Lazy to make sure the current url is always written, but that
+would mean that we couldn't trace a tab's full lifetime through our
+logs after the user navigate to a new URL.
+
+Instead, think about what values to attach to your loggers the
+same way you think about what to use as a key in a SQL database schema.
+If it's possible to use a natural key that is unique for the lifetime of the
+object, do so. But otherwise, log15's ext package has a handy RandId
+function to let you generate what you might call "surrogate keys"
+They're just random hex identifiers to use for tracing. Back to our
+Tab example, we would prefer to set up our Logger like so:
+
+ import logext "github.com/inconshreveable/log15/ext"
+
+ t := &Tab {
+ // ...
+ url: url,
+ }
+
+ t.Logger = log.New("id", logext.RandId(8), "url", log.Lazy{t.getUrl})
+ return t
+
+Now we'll have a unique traceable identifier even across loading new urls, but
+we'll still be able to see the tab's current url in the log messages.
+
+Must
+
+For all Handler functions which can return an error, there is a version of that
+function which will return no error but panics on failure. They are all available
+on the Must object. For example:
+
+ log.Must.FileHandler("/path", log.JsonFormat)
+ log.Must.NetHandler("tcp", ":1234", log.JsonFormat)
+
+Inspiration and Credit
+
+All of the following excellent projects inspired the design of this library:
+
+code.google.com/p/log4go
+
+github.com/op/go-logging
+
+github.com/technoweenie/grohl
+
+github.com/Sirupsen/logrus
+
+github.com/kr/logfmt
+
+github.com/spacemonkeygo/spacelog
+
+golang's stdlib, notably io and net/http
+
+The Name
+
+https://xkcd.com/927/
+
+*/
+package log
diff --git a/log/format.go b/log/format.go
new file mode 100644
index 000000000..376376183
--- /dev/null
+++ b/log/format.go
@@ -0,0 +1,279 @@
+package log
+
+import (
+ "bytes"
+ "encoding/json"
+ "fmt"
+ "reflect"
+ "strconv"
+ "strings"
+ "sync"
+ "time"
+)
+
+const (
+ timeFormat = "2006-01-02T15:04:05-0700"
+ termTimeFormat = "01-02|15:04:05"
+ floatFormat = 'f'
+ termMsgJust = 40
+)
+
+type Format interface {
+ Format(r *Record) []byte
+}
+
+// FormatFunc returns a new Format object which uses
+// the given function to perform record formatting.
+func FormatFunc(f func(*Record) []byte) Format {
+ return formatFunc(f)
+}
+
+type formatFunc func(*Record) []byte
+
+func (f formatFunc) Format(r *Record) []byte {
+ return f(r)
+}
+
+// TerminalFormat formats log records optimized for human readability on
+// a terminal with color-coded level output and terser human friendly timestamp.
+// This format should only be used for interactive programs or while developing.
+//
+// [TIME] [LEVEL] MESAGE key=value key=value ...
+//
+// Example:
+//
+// [May 16 20:58:45] [DBUG] remove route ns=haproxy addr=127.0.0.1:50002
+//
+func TerminalFormat() Format {
+ return FormatFunc(func(r *Record) []byte {
+ var color = 0
+ switch r.Lvl {
+ case LvlCrit:
+ color = 35
+ case LvlError:
+ color = 31
+ case LvlWarn:
+ color = 33
+ case LvlInfo:
+ color = 32
+ case LvlDebug:
+ color = 36
+ }
+
+ b := &bytes.Buffer{}
+ lvl := strings.ToUpper(r.Lvl.String())
+ if color > 0 {
+ fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %s ", color, lvl, r.Time.Format(termTimeFormat), r.Msg)
+ } else {
+ fmt.Fprintf(b, "[%s] [%s] %s ", lvl, r.Time.Format(termTimeFormat), r.Msg)
+ }
+
+ // try to justify the log output for short messages
+ if len(r.Ctx) > 0 && len(r.Msg) < termMsgJust {
+ b.Write(bytes.Repeat([]byte{' '}, termMsgJust-len(r.Msg)))
+ }
+
+ // print the keys logfmt style
+ logfmt(b, r.Ctx, color)
+ return b.Bytes()
+ })
+}
+
+// LogfmtFormat prints records in logfmt format, an easy machine-parseable but human-readable
+// format for key/value pairs.
+//
+// For more details see: http://godoc.org/github.com/kr/logfmt
+//
+func LogfmtFormat() Format {
+ return FormatFunc(func(r *Record) []byte {
+ common := []interface{}{r.KeyNames.Time, r.Time, r.KeyNames.Lvl, r.Lvl, r.KeyNames.Msg, r.Msg}
+ buf := &bytes.Buffer{}
+ logfmt(buf, append(common, r.Ctx...), 0)
+ return buf.Bytes()
+ })
+}
+
+func logfmt(buf *bytes.Buffer, ctx []interface{}, color int) {
+ for i := 0; i < len(ctx); i += 2 {
+ if i != 0 {
+ buf.WriteByte(' ')
+ }
+
+ k, ok := ctx[i].(string)
+ v := formatLogfmtValue(ctx[i+1])
+ if !ok {
+ k, v = errorKey, formatLogfmtValue(k)
+ }
+
+ // XXX: we should probably check that all of your key bytes aren't invalid
+ if color > 0 {
+ fmt.Fprintf(buf, "\x1b[%dm%s\x1b[0m=%s", color, k, v)
+ } else {
+ buf.WriteString(k)
+ buf.WriteByte('=')
+ buf.WriteString(v)
+ }
+ }
+
+ buf.WriteByte('\n')
+}
+
+// JsonFormat formats log records as JSON objects separated by newlines.
+// It is the equivalent of JsonFormatEx(false, true).
+func JsonFormat() Format {
+ return JsonFormatEx(false, true)
+}
+
+// JsonFormatEx formats log records as JSON objects. If pretty is true,
+// records will be pretty-printed. If lineSeparated is true, records
+// will be logged with a new line between each record.
+func JsonFormatEx(pretty, lineSeparated bool) Format {
+ jsonMarshal := json.Marshal
+ if pretty {
+ jsonMarshal = func(v interface{}) ([]byte, error) {
+ return json.MarshalIndent(v, "", " ")
+ }
+ }
+
+ return FormatFunc(func(r *Record) []byte {
+ props := make(map[string]interface{})
+
+ props[r.KeyNames.Time] = r.Time
+ props[r.KeyNames.Lvl] = r.Lvl.String()
+ props[r.KeyNames.Msg] = r.Msg
+
+ for i := 0; i < len(r.Ctx); i += 2 {
+ k, ok := r.Ctx[i].(string)
+ if !ok {
+ props[errorKey] = fmt.Sprintf("%+v is not a string key", r.Ctx[i])
+ }
+ props[k] = formatJsonValue(r.Ctx[i+1])
+ }
+
+ b, err := jsonMarshal(props)
+ if err != nil {
+ b, _ = jsonMarshal(map[string]string{
+ errorKey: err.Error(),
+ })
+ return b
+ }
+
+ if lineSeparated {
+ b = append(b, '\n')
+ }
+
+ return b
+ })
+}
+
+func formatShared(value interface{}) (result interface{}) {
+ defer func() {
+ if err := recover(); err != nil {
+ if v := reflect.ValueOf(value); v.Kind() == reflect.Ptr && v.IsNil() {
+ result = "nil"
+ } else {
+ panic(err)
+ }
+ }
+ }()
+
+ switch v := value.(type) {
+ case time.Time:
+ return v.Format(timeFormat)
+
+ case error:
+ return v.Error()
+
+ case fmt.Stringer:
+ return v.String()
+
+ default:
+ return v
+ }
+}
+
+func formatJsonValue(value interface{}) interface{} {
+ value = formatShared(value)
+ switch value.(type) {
+ case int, int8, int16, int32, int64, float32, float64, uint, uint8, uint16, uint32, uint64, string:
+ return value
+ default:
+ return fmt.Sprintf("%+v", value)
+ }
+}
+
+// formatValue formats a value for serialization
+func formatLogfmtValue(value interface{}) string {
+ if value == nil {
+ return "nil"
+ }
+
+ if t, ok := value.(time.Time); ok {
+ // Performance optimization: No need for escaping since the provided
+ // timeFormat doesn't have any escape characters, and escaping is
+ // expensive.
+ return t.Format(timeFormat)
+ }
+ value = formatShared(value)
+ switch v := value.(type) {
+ case bool:
+ return strconv.FormatBool(v)
+ case float32:
+ return strconv.FormatFloat(float64(v), floatFormat, 3, 64)
+ case float64:
+ return strconv.FormatFloat(v, floatFormat, 3, 64)
+ case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
+ return fmt.Sprintf("%d", value)
+ case string:
+ return escapeString(v)
+ default:
+ return escapeString(fmt.Sprintf("%+v", value))
+ }
+}
+
+var stringBufPool = sync.Pool{
+ New: func() interface{} { return new(bytes.Buffer) },
+}
+
+func escapeString(s string) string {
+ needsQuotes := false
+ needsEscape := false
+ for _, r := range s {
+ if r <= ' ' || r == '=' || r == '"' {
+ needsQuotes = true
+ }
+ if r == '\\' || r == '"' || r == '\n' || r == '\r' || r == '\t' {
+ needsEscape = true
+ }
+ }
+ if needsEscape == false && needsQuotes == false {
+ return s
+ }
+ e := stringBufPool.Get().(*bytes.Buffer)
+ e.WriteByte('"')
+ for _, r := range s {
+ switch r {
+ case '\\', '"':
+ e.WriteByte('\\')
+ e.WriteByte(byte(r))
+ case '\n':
+ e.WriteString("\\n")
+ case '\r':
+ e.WriteString("\\r")
+ case '\t':
+ e.WriteString("\\t")
+ default:
+ e.WriteRune(r)
+ }
+ }
+ e.WriteByte('"')
+ var ret string
+ if needsQuotes {
+ ret = e.String()
+ } else {
+ ret = string(e.Bytes()[1 : e.Len()-1])
+ }
+ e.Reset()
+ stringBufPool.Put(e)
+ return ret
+}
diff --git a/log/handler.go b/log/handler.go
new file mode 100644
index 000000000..abb17b4c4
--- /dev/null
+++ b/log/handler.go
@@ -0,0 +1,356 @@
+package log
+
+import (
+ "fmt"
+ "io"
+ "net"
+ "os"
+ "reflect"
+ "sync"
+
+ "github.com/go-stack/stack"
+)
+
+// A Logger prints its log records by writing to a Handler.
+// The Handler interface defines where and how log records are written.
+// Handlers are composable, providing you great flexibility in combining
+// them to achieve the logging structure that suits your applications.
+type Handler interface {
+ Log(r *Record) error
+}
+
+// FuncHandler returns a Handler that logs records with the given
+// function.
+func FuncHandler(fn func(r *Record) error) Handler {
+ return funcHandler(fn)
+}
+
+type funcHandler func(r *Record) error
+
+func (h funcHandler) Log(r *Record) error {
+ return h(r)
+}
+
+// StreamHandler writes log records to an io.Writer
+// with the given format. StreamHandler can be used
+// to easily begin writing log records to other
+// outputs.
+//
+// StreamHandler wraps itself with LazyHandler and SyncHandler
+// to evaluate Lazy objects and perform safe concurrent writes.
+func StreamHandler(wr io.Writer, fmtr Format) Handler {
+ h := FuncHandler(func(r *Record) error {
+ _, err := wr.Write(fmtr.Format(r))
+ return err
+ })
+ return LazyHandler(SyncHandler(h))
+}
+
+// SyncHandler can be wrapped around a handler to guarantee that
+// only a single Log operation can proceed at a time. It's necessary
+// for thread-safe concurrent writes.
+func SyncHandler(h Handler) Handler {
+ var mu sync.Mutex
+ return FuncHandler(func(r *Record) error {
+ defer mu.Unlock()
+ mu.Lock()
+ return h.Log(r)
+ })
+}
+
+// FileHandler returns a handler which writes log records to the give file
+// using the given format. If the path
+// already exists, FileHandler will append to the given file. If it does not,
+// FileHandler will create the file with mode 0644.
+func FileHandler(path string, fmtr Format) (Handler, error) {
+ f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
+ if err != nil {
+ return nil, err
+ }
+ return closingHandler{f, StreamHandler(f, fmtr)}, nil
+}
+
+// NetHandler opens a socket to the given address and writes records
+// over the connection.
+func NetHandler(network, addr string, fmtr Format) (Handler, error) {
+ conn, err := net.Dial(network, addr)
+ if err != nil {
+ return nil, err
+ }
+
+ return closingHandler{conn, StreamHandler(conn, fmtr)}, nil
+}
+
+// XXX: closingHandler is essentially unused at the moment
+// it's meant for a future time when the Handler interface supports
+// a possible Close() operation
+type closingHandler struct {
+ io.WriteCloser
+ Handler
+}
+
+func (h *closingHandler) Close() error {
+ return h.WriteCloser.Close()
+}
+
+// CallerFileHandler returns a Handler that adds the line number and file of
+// the calling function to the context with key "caller".
+func CallerFileHandler(h Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ r.Ctx = append(r.Ctx, "caller", fmt.Sprint(r.Call))
+ return h.Log(r)
+ })
+}
+
+// CallerFuncHandler returns a Handler that adds the calling function name to
+// the context with key "fn".
+func CallerFuncHandler(h Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ r.Ctx = append(r.Ctx, "fn", fmt.Sprintf("%+n", r.Call))
+ return h.Log(r)
+ })
+}
+
+// CallerStackHandler returns a Handler that adds a stack trace to the context
+// with key "stack". The stack trace is formated as a space separated list of
+// call sites inside matching []'s. The most recent call site is listed first.
+// Each call site is formatted according to format. See the documentation of
+// package github.com/go-stack/stack for the list of supported formats.
+func CallerStackHandler(format string, h Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ s := stack.Trace().TrimBelow(r.Call).TrimRuntime()
+ if len(s) > 0 {
+ r.Ctx = append(r.Ctx, "stack", fmt.Sprintf(format, s))
+ }
+ return h.Log(r)
+ })
+}
+
+// FilterHandler returns a Handler that only writes records to the
+// wrapped Handler if the given function evaluates true. For example,
+// to only log records where the 'err' key is not nil:
+//
+// logger.SetHandler(FilterHandler(func(r *Record) bool {
+// for i := 0; i < len(r.Ctx); i += 2 {
+// if r.Ctx[i] == "err" {
+// return r.Ctx[i+1] != nil
+// }
+// }
+// return false
+// }, h))
+//
+func FilterHandler(fn func(r *Record) bool, h Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ if fn(r) {
+ return h.Log(r)
+ }
+ return nil
+ })
+}
+
+// MatchFilterHandler returns a Handler that only writes records
+// to the wrapped Handler if the given key in the logged
+// context matches the value. For example, to only log records
+// from your ui package:
+//
+// log.MatchFilterHandler("pkg", "app/ui", log.StdoutHandler)
+//
+func MatchFilterHandler(key string, value interface{}, h Handler) Handler {
+ return FilterHandler(func(r *Record) (pass bool) {
+ switch key {
+ case r.KeyNames.Lvl:
+ return r.Lvl == value
+ case r.KeyNames.Time:
+ return r.Time == value
+ case r.KeyNames.Msg:
+ return r.Msg == value
+ }
+
+ for i := 0; i < len(r.Ctx); i += 2 {
+ if r.Ctx[i] == key {
+ return r.Ctx[i+1] == value
+ }
+ }
+ return false
+ }, h)
+}
+
+// LvlFilterHandler returns a Handler that only writes
+// records which are less than the given verbosity
+// level to the wrapped Handler. For example, to only
+// log Error/Crit records:
+//
+// log.LvlFilterHandler(log.LvlError, log.StdoutHandler)
+//
+func LvlFilterHandler(maxLvl Lvl, h Handler) Handler {
+ return FilterHandler(func(r *Record) (pass bool) {
+ return r.Lvl <= maxLvl
+ }, h)
+}
+
+// A MultiHandler dispatches any write to each of its handlers.
+// This is useful for writing different types of log information
+// to different locations. For example, to log to a file and
+// standard error:
+//
+// log.MultiHandler(
+// log.Must.FileHandler("/var/log/app.log", log.LogfmtFormat()),
+// log.StderrHandler)
+//
+func MultiHandler(hs ...Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ for _, h := range hs {
+ // what to do about failures?
+ h.Log(r)
+ }
+ return nil
+ })
+}
+
+// A FailoverHandler writes all log records to the first handler
+// specified, but will failover and write to the second handler if
+// the first handler has failed, and so on for all handlers specified.
+// For example you might want to log to a network socket, but failover
+// to writing to a file if the network fails, and then to
+// standard out if the file write fails:
+//
+// log.FailoverHandler(
+// log.Must.NetHandler("tcp", ":9090", log.JsonFormat()),
+// log.Must.FileHandler("/var/log/app.log", log.LogfmtFormat()),
+// log.StdoutHandler)
+//
+// All writes that do not go to the first handler will add context with keys of
+// the form "failover_err_{idx}" which explain the error encountered while
+// trying to write to the handlers before them in the list.
+func FailoverHandler(hs ...Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ var err error
+ for i, h := range hs {
+ err = h.Log(r)
+ if err == nil {
+ return nil
+ } else {
+ r.Ctx = append(r.Ctx, fmt.Sprintf("failover_err_%d", i), err)
+ }
+ }
+
+ return err
+ })
+}
+
+// ChannelHandler writes all records to the given channel.
+// It blocks if the channel is full. Useful for async processing
+// of log messages, it's used by BufferedHandler.
+func ChannelHandler(recs chan<- *Record) Handler {
+ return FuncHandler(func(r *Record) error {
+ recs <- r
+ return nil
+ })
+}
+
+// BufferedHandler writes all records to a buffered
+// channel of the given size which flushes into the wrapped
+// handler whenever it is available for writing. Since these
+// writes happen asynchronously, all writes to a BufferedHandler
+// never return an error and any errors from the wrapped handler are ignored.
+func BufferedHandler(bufSize int, h Handler) Handler {
+ recs := make(chan *Record, bufSize)
+ go func() {
+ for m := range recs {
+ _ = h.Log(m)
+ }
+ }()
+ return ChannelHandler(recs)
+}
+
+// LazyHandler writes all values to the wrapped handler after evaluating
+// any lazy functions in the record's context. It is already wrapped
+// around StreamHandler and SyslogHandler in this library, you'll only need
+// it if you write your own Handler.
+func LazyHandler(h Handler) Handler {
+ return FuncHandler(func(r *Record) error {
+ // go through the values (odd indices) and reassign
+ // the values of any lazy fn to the result of its execution
+ hadErr := false
+ for i := 1; i < len(r.Ctx); i += 2 {
+ lz, ok := r.Ctx[i].(Lazy)
+ if ok {
+ v, err := evaluateLazy(lz)
+ if err != nil {
+ hadErr = true
+ r.Ctx[i] = err
+ } else {
+ if cs, ok := v.(stack.CallStack); ok {
+ v = cs.TrimBelow(r.Call).TrimRuntime()
+ }
+ r.Ctx[i] = v
+ }
+ }
+ }
+
+ if hadErr {
+ r.Ctx = append(r.Ctx, errorKey, "bad lazy")
+ }
+
+ return h.Log(r)
+ })
+}
+
+func evaluateLazy(lz Lazy) (interface{}, error) {
+ t := reflect.TypeOf(lz.Fn)
+
+ if t.Kind() != reflect.Func {
+ return nil, fmt.Errorf("INVALID_LAZY, not func: %+v", lz.Fn)
+ }
+
+ if t.NumIn() > 0 {
+ return nil, fmt.Errorf("INVALID_LAZY, func takes args: %+v", lz.Fn)
+ }
+
+ if t.NumOut() == 0 {
+ return nil, fmt.Errorf("INVALID_LAZY, no func return val: %+v", lz.Fn)
+ }
+
+ value := reflect.ValueOf(lz.Fn)
+ results := value.Call([]reflect.Value{})
+ if len(results) == 1 {
+ return results[0].Interface(), nil
+ } else {
+ values := make([]interface{}, len(results))
+ for i, v := range results {
+ values[i] = v.Interface()
+ }
+ return values, nil
+ }
+}
+
+// DiscardHandler reports success for all writes but does nothing.
+// It is useful for dynamically disabling logging at runtime via
+// a Logger's SetHandler method.
+func DiscardHandler() Handler {
+ return FuncHandler(func(r *Record) error {
+ return nil
+ })
+}
+
+// The Must object provides the following Handler creation functions
+// which instead of returning an error parameter only return a Handler
+// and panic on failure: FileHandler, NetHandler, SyslogHandler, SyslogNetHandler
+var Must muster
+
+func must(h Handler, err error) Handler {
+ if err != nil {
+ panic(err)
+ }
+ return h
+}
+
+type muster struct{}
+
+func (m muster) FileHandler(path string, fmtr Format) Handler {
+ return must(FileHandler(path, fmtr))
+}
+
+func (m muster) NetHandler(network, addr string, fmtr Format) Handler {
+ return must(NetHandler(network, addr, fmtr))
+}
diff --git a/log/handler_go13.go b/log/handler_go13.go
new file mode 100644
index 000000000..0843ed0e5
--- /dev/null
+++ b/log/handler_go13.go
@@ -0,0 +1,26 @@
+// +build !go1.4
+
+package log
+
+import (
+ "sync/atomic"
+ "unsafe"
+)
+
+// swapHandler wraps another handler that may be swapped out
+// dynamically at runtime in a thread-safe fashion.
+type swapHandler struct {
+ handler unsafe.Pointer
+}
+
+func (h *swapHandler) Log(r *Record) error {
+ return h.Get().Log(r)
+}
+
+func (h *swapHandler) Get() Handler {
+ return *(*Handler)(atomic.LoadPointer(&h.handler))
+}
+
+func (h *swapHandler) Swap(newHandler Handler) {
+ atomic.StorePointer(&h.handler, unsafe.Pointer(&newHandler))
+}
diff --git a/log/handler_go14.go b/log/handler_go14.go
new file mode 100644
index 000000000..05dedbf2a
--- /dev/null
+++ b/log/handler_go14.go
@@ -0,0 +1,23 @@
+// +build go1.4
+
+package log
+
+import "sync/atomic"
+
+// swapHandler wraps another handler that may be swapped out
+// dynamically at runtime in a thread-safe fashion.
+type swapHandler struct {
+ handler atomic.Value
+}
+
+func (h *swapHandler) Log(r *Record) error {
+ return (*h.handler.Load().(*Handler)).Log(r)
+}
+
+func (h *swapHandler) Swap(newHandler Handler) {
+ h.handler.Store(&newHandler)
+}
+
+func (h *swapHandler) Get() Handler {
+ return *h.handler.Load().(*Handler)
+}
diff --git a/log/logger.go b/log/logger.go
new file mode 100644
index 000000000..a9d42b8da
--- /dev/null
+++ b/log/logger.go
@@ -0,0 +1,208 @@
+package log
+
+import (
+ "fmt"
+ "time"
+
+ "github.com/go-stack/stack"
+)
+
+const timeKey = "t"
+const lvlKey = "lvl"
+const msgKey = "msg"
+const errorKey = "LOG15_ERROR"
+
+type Lvl int
+
+const (
+ LvlCrit Lvl = iota
+ LvlError
+ LvlWarn
+ LvlInfo
+ LvlDebug
+)
+
+// Returns the name of a Lvl
+func (l Lvl) String() string {
+ switch l {
+ case LvlDebug:
+ return "dbug"
+ case LvlInfo:
+ return "info"
+ case LvlWarn:
+ return "warn"
+ case LvlError:
+ return "eror"
+ case LvlCrit:
+ return "crit"
+ default:
+ panic("bad level")
+ }
+}
+
+// Returns the appropriate Lvl from a string name.
+// Useful for parsing command line args and configuration files.
+func LvlFromString(lvlString string) (Lvl, error) {
+ switch lvlString {
+ case "debug", "dbug":
+ return LvlDebug, nil
+ case "info":
+ return LvlInfo, nil
+ case "warn":
+ return LvlWarn, nil
+ case "error", "eror":
+ return LvlError, nil
+ case "crit":
+ return LvlCrit, nil
+ default:
+ return LvlDebug, fmt.Errorf("Unknown level: %v", lvlString)
+ }
+}
+
+// A Record is what a Logger asks its handler to write
+type Record struct {
+ Time time.Time
+ Lvl Lvl
+ Msg string
+ Ctx []interface{}
+ Call stack.Call
+ KeyNames RecordKeyNames
+}
+
+type RecordKeyNames struct {
+ Time string
+ Msg string
+ Lvl string
+}
+
+// A Logger writes key/value pairs to a Handler
+type Logger interface {
+ // New returns a new Logger that has this logger's context plus the given context
+ New(ctx ...interface{}) Logger
+
+ // GetHandler gets the handler associated with the logger.
+ GetHandler() Handler
+
+ // SetHandler updates the logger to write records to the specified handler.
+ SetHandler(h Handler)
+
+ // Log a message at the given level with context key/value pairs
+ Debug(msg string, ctx ...interface{})
+ Info(msg string, ctx ...interface{})
+ Warn(msg string, ctx ...interface{})
+ Error(msg string, ctx ...interface{})
+ Crit(msg string, ctx ...interface{})
+}
+
+type logger struct {
+ ctx []interface{}
+ h *swapHandler
+}
+
+func (l *logger) write(msg string, lvl Lvl, ctx []interface{}) {
+ l.h.Log(&Record{
+ Time: time.Now(),
+ Lvl: lvl,
+ Msg: msg,
+ Ctx: newContext(l.ctx, ctx),
+ Call: stack.Caller(2),
+ KeyNames: RecordKeyNames{
+ Time: timeKey,
+ Msg: msgKey,
+ Lvl: lvlKey,
+ },
+ })
+}
+
+func (l *logger) New(ctx ...interface{}) Logger {
+ child := &logger{newContext(l.ctx, ctx), new(swapHandler)}
+ child.SetHandler(l.h)
+ return child
+}
+
+func newContext(prefix []interface{}, suffix []interface{}) []interface{} {
+ normalizedSuffix := normalize(suffix)
+ newCtx := make([]interface{}, len(prefix)+len(normalizedSuffix))
+ n := copy(newCtx, prefix)
+ copy(newCtx[n:], normalizedSuffix)
+ return newCtx
+}
+
+func (l *logger) Debug(msg string, ctx ...interface{}) {
+ l.write(msg, LvlDebug, ctx)
+}
+
+func (l *logger) Info(msg string, ctx ...interface{}) {
+ l.write(msg, LvlInfo, ctx)
+}
+
+func (l *logger) Warn(msg string, ctx ...interface{}) {
+ l.write(msg, LvlWarn, ctx)
+}
+
+func (l *logger) Error(msg string, ctx ...interface{}) {
+ l.write(msg, LvlError, ctx)
+}
+
+func (l *logger) Crit(msg string, ctx ...interface{}) {
+ l.write(msg, LvlCrit, ctx)
+}
+
+func (l *logger) GetHandler() Handler {
+ return l.h.Get()
+}
+
+func (l *logger) SetHandler(h Handler) {
+ l.h.Swap(h)
+}
+
+func normalize(ctx []interface{}) []interface{} {
+ // if the caller passed a Ctx object, then expand it
+ if len(ctx) == 1 {
+ if ctxMap, ok := ctx[0].(Ctx); ok {
+ ctx = ctxMap.toArray()
+ }
+ }
+
+ // ctx needs to be even because it's a series of key/value pairs
+ // no one wants to check for errors on logging functions,
+ // so instead of erroring on bad input, we'll just make sure
+ // that things are the right length and users can fix bugs
+ // when they see the output looks wrong
+ if len(ctx)%2 != 0 {
+ ctx = append(ctx, nil, errorKey, "Normalized odd number of arguments by adding nil")
+ }
+
+ return ctx
+}
+
+// Lazy allows you to defer calculation of a logged value that is expensive
+// to compute until it is certain that it must be evaluated with the given filters.
+//
+// Lazy may also be used in conjunction with a Logger's New() function
+// to generate a child logger which always reports the current value of changing
+// state.
+//
+// You may wrap any function which takes no arguments to Lazy. It may return any
+// number of values of any type.
+type Lazy struct {
+ Fn interface{}
+}
+
+// Ctx is a map of key/value pairs to pass as context to a log function
+// Use this only if you really need greater safety around the arguments you pass
+// to the logging functions.
+type Ctx map[string]interface{}
+
+func (c Ctx) toArray() []interface{} {
+ arr := make([]interface{}, len(c)*2)
+
+ i := 0
+ for k, v := range c {
+ arr[i] = k
+ arr[i+1] = v
+ i += 2
+ }
+
+ return arr
+}
diff --git a/log/root.go b/log/root.go
new file mode 100644
index 000000000..39b4c9429
--- /dev/null
+++ b/log/root.go
@@ -0,0 +1,67 @@
+package log
+
+import (
+ "os"
+
+ "github.com/ethereum/go-ethereum/log/term"
+ "github.com/mattn/go-colorable"
+)
+
+var (
+ root *logger
+ StdoutHandler = StreamHandler(os.Stdout, LogfmtFormat())
+ StderrHandler = StreamHandler(os.Stderr, LogfmtFormat())
+)
+
+func init() {
+ if term.IsTty(os.Stdout.Fd()) {
+ StdoutHandler = StreamHandler(colorable.NewColorableStdout(), TerminalFormat())
+ }
+
+ if term.IsTty(os.Stderr.Fd()) {
+ StderrHandler = StreamHandler(colorable.NewColorableStderr(), TerminalFormat())
+ }
+
+ root = &logger{[]interface{}{}, new(swapHandler)}
+ root.SetHandler(StdoutHandler)
+}
+
+// New returns a new logger with the given context.
+// New is a convenient alias for Root().New
+func New(ctx ...interface{}) Logger {
+ return root.New(ctx...)
+}
+
+// Root returns the root logger
+func Root() Logger {
+ return root
+}
+
+// The following functions bypass the exported logger methods (logger.Debug,
+// etc.) to keep the call depth the same for all paths to logger.write so
+// runtime.Caller(2) always refers to the call site in client code.
+
+// Debug is a convenient alias for Root().Debug
+func Debug(msg string, ctx ...interface{}) {
+ root.write(msg, LvlDebug, ctx)
+}
+
+// Info is a convenient alias for Root().Info
+func Info(msg string, ctx ...interface{}) {
+ root.write(msg, LvlInfo, ctx)
+}
+
+// Warn is a convenient alias for Root().Warn
+func Warn(msg string, ctx ...interface{}) {
+ root.write(msg, LvlWarn, ctx)
+}
+
+// Error is a convenient alias for Root().Error
+func Error(msg string, ctx ...interface{}) {
+ root.write(msg, LvlError, ctx)
+}
+
+// Crit is a convenient alias for Root().Crit
+func Crit(msg string, ctx ...interface{}) {
+ root.write(msg, LvlCrit, ctx)
+}
diff --git a/log/syslog.go b/log/syslog.go
new file mode 100644
index 000000000..4f1097ff9
--- /dev/null
+++ b/log/syslog.go
@@ -0,0 +1,55 @@
+// +build !windows,!plan9
+
+package log
+
+import (
+ "log/syslog"
+ "strings"
+)
+
+// SyslogHandler opens a connection to the system syslog daemon by calling
+// syslog.New and writes all records to it.
+func SyslogHandler(priority syslog.Priority, tag string, fmtr Format) (Handler, error) {
+ wr, err := syslog.New(priority, tag)
+ return sharedSyslog(fmtr, wr, err)
+}
+
+// SyslogNetHandler opens a connection to a log daemon over the network and writes
+// all log records to it.
+func SyslogNetHandler(net, addr string, priority syslog.Priority, tag string, fmtr Format) (Handler, error) {
+ wr, err := syslog.Dial(net, addr, priority, tag)
+ return sharedSyslog(fmtr, wr, err)
+}
+
+func sharedSyslog(fmtr Format, sysWr *syslog.Writer, err error) (Handler, error) {
+ if err != nil {
+ return nil, err
+ }
+ h := FuncHandler(func(r *Record) error {
+ var syslogFn = sysWr.Info
+ switch r.Lvl {
+ case LvlCrit:
+ syslogFn = sysWr.Crit
+ case LvlError:
+ syslogFn = sysWr.Err
+ case LvlWarn:
+ syslogFn = sysWr.Warning
+ case LvlInfo:
+ syslogFn = sysWr.Info
+ case LvlDebug:
+ syslogFn = sysWr.Debug
+ }
+
+ s := strings.TrimSpace(string(fmtr.Format(r)))
+ return syslogFn(s)
+ })
+ return LazyHandler(&closingHandler{sysWr, h}), nil
+}
+
+func (m muster) SyslogHandler(priority syslog.Priority, tag string, fmtr Format) Handler {
+ return must(SyslogHandler(priority, tag, fmtr))
+}
+
+func (m muster) SyslogNetHandler(net, addr string, priority syslog.Priority, tag string, fmtr Format) Handler {
+ return must(SyslogNetHandler(net, addr, priority, tag, fmtr))
+}
diff --git a/log/term/LICENSE b/log/term/LICENSE
new file mode 100644
index 000000000..f090cb42f
--- /dev/null
+++ b/log/term/LICENSE
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Simon Eskildsen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/log/term/terminal_appengine.go b/log/term/terminal_appengine.go
new file mode 100644
index 000000000..c1b5d2a3b
--- /dev/null
+++ b/log/term/terminal_appengine.go
@@ -0,0 +1,13 @@
+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build appengine
+
+package term
+
+// IsTty always returns false on AppEngine.
+func IsTty(fd uintptr) bool {
+ return false
+}
diff --git a/log/term/terminal_darwin.go b/log/term/terminal_darwin.go
new file mode 100644
index 000000000..d8f351b1b
--- /dev/null
+++ b/log/term/terminal_darwin.go
@@ -0,0 +1,13 @@
+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+// +build !appengine
+
+package term
+
+import "syscall"
+
+const ioctlReadTermios = syscall.TIOCGETA
+
+type Termios syscall.Termios
diff --git a/log/term/terminal_freebsd.go b/log/term/terminal_freebsd.go
new file mode 100644
index 000000000..cfaceab33
--- /dev/null
+++ b/log/term/terminal_freebsd.go
@@ -0,0 +1,18 @@
+package term
+
+import (
+ "syscall"
+)
+
+const ioctlReadTermios = syscall.TIOCGETA
+
+// Go 1.2 doesn't include Termios for FreeBSD. This should be added in 1.3 and this could be merged with terminal_darwin.
+type Termios struct {
+ Iflag uint32
+ Oflag uint32
+ Cflag uint32
+ Lflag uint32
+ Cc [20]uint8
+ Ispeed uint32
+ Ospeed uint32
+}
diff --git a/log/term/terminal_linux.go b/log/term/terminal_linux.go
new file mode 100644
index 000000000..5290468d6
--- /dev/null
+++ b/log/term/terminal_linux.go
@@ -0,0 +1,14 @@
+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !appengine
+
+package term
+
+import "syscall"
+
+const ioctlReadTermios = syscall.TCGETS
+
+type Termios syscall.Termios
diff --git a/log/term/terminal_netbsd.go b/log/term/terminal_netbsd.go
new file mode 100644
index 000000000..f9bb9e1c2
--- /dev/null
+++ b/log/term/terminal_netbsd.go
@@ -0,0 +1,7 @@
+package term
+
+import "syscall"
+
+const ioctlReadTermios = syscall.TIOCGETA
+
+type Termios syscall.Termios
diff --git a/log/term/terminal_notwindows.go b/log/term/terminal_notwindows.go
new file mode 100644
index 000000000..c9af534f6
--- /dev/null
+++ b/log/term/terminal_notwindows.go
@@ -0,0 +1,20 @@
+// Based on ssh/terminal:
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux,!appengine darwin freebsd openbsd netbsd
+
+package term
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+// IsTty returns true if the given file descriptor is a terminal.
+func IsTty(fd uintptr) bool {
+ var termios Termios
+ _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, fd, ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
+ return err == 0
+}
diff --git a/log/term/terminal_openbsd.go b/log/term/terminal_openbsd.go
new file mode 100644
index 000000000..f9bb9e1c2
--- /dev/null
+++ b/log/term/terminal_openbsd.go
@@ -0,0 +1,7 @@
+package term
+
+import "syscall"
+
+const ioctlReadTermios = syscall.TIOCGETA
+
+type Termios syscall.Termios
diff --git a/log/term/terminal_solaris.go b/log/term/terminal_solaris.go
new file mode 100644
index 000000000..033c16324
--- /dev/null
+++ b/log/term/terminal_solaris.go
@@ -0,0 +1,9 @@
+package term
+
+import "golang.org/x/sys/unix"
+
+// IsTty returns true if the given file descriptor is a terminal.
+func IsTty(fd uintptr) bool {
+ _, err := unix.IoctlGetTermios(int(fd), unix.TCGETA)
+ return err == nil
+}
diff --git a/log/term/terminal_windows.go b/log/term/terminal_windows.go
new file mode 100644
index 000000000..df3c30c15
--- /dev/null
+++ b/log/term/terminal_windows.go
@@ -0,0 +1,26 @@
+// Based on ssh/terminal:
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package term
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+var kernel32 = syscall.NewLazyDLL("kernel32.dll")
+
+var (
+ procGetConsoleMode = kernel32.NewProc("GetConsoleMode")
+)
+
+// IsTty returns true if the given file descriptor is a terminal.
+func IsTty(fd uintptr) bool {
+ var st uint32
+ r, _, e := syscall.Syscall(procGetConsoleMode.Addr(), 2, fd, uintptr(unsafe.Pointer(&st)), 0)
+ return r != 0 && e == 0
+}