log: new interface

New logging interface simplifies and generalizes.

1) Loggers now have only one output.
2) log.Stdout, Stderr, Crash and friends are gone.
	Logging is now always to standard error by default.
3) log.Panic* replaces log.Crash*.
4) Exiting and panicking are not part of the logger's state; instead
	the functions Exit* and Panic* simply call Exit or panic after
	printing.
5) There is now one 'standard logger'.  Instead of calling Stderr,
	use Print etc.  There are now triples, by analogy with fmt:
		Print, Println, Printf
	What was log.Stderr is now best represented by log.Println,
	since there are now separate Print and Println functions
	(and methods).
6) New functions SetOutput, SetFlags, and SetPrefix allow global
	editing of the standard logger's properties.   This is new
	functionality. For instance, one can call
		log.SetFlags(log.Lshortfile|log.Ltime|log.Lmicroseconds)
	to get all logging output to show file name, line number, and
	time stamp.

In short, for most purposes
	log.Stderr -> log.Println or log.Print
	log.Stderrf -> log.Printf
	log.Crash -> log.Panicln or log.Panic
	log.Crashf -> log.Panicf
	log.Exit -> log.Exitln or log.Exit
	log.Exitf -> log.Exitf (no change)

This has a slight breakage: since loggers now write only to one
output, existing calls to log.New() need to delete the second argument.
Also, custom loggers with exit or panic properties will need to be
reworked.

All package code updated to new interface.

The test has been reworked somewhat.

The old interface will be removed after the new release.
For now, its elements are marked 'deprecated' in their comments.

Fixes #1184.

R=rsc
CC=golang-dev
https://golang.org/cl/2419042

1 files changed, 4 insertions, 4 deletions

diff --git a/src/pkg/http/server.go b/src/pkg/http/server.go
index 03653ef87d..44ad8f1df9 100644
--- a/src/pkg/http/server.go
+++ b/src/pkg/http/server.go
@@ -212,11 +212,11 @@ func (w *response) SetHeader(hdr, val string) { w.header[CanonicalHeaderKey(hdr)
 // WriteHeader implements the ResponseWriter.WriteHeader method
 func (w *response) WriteHeader(code int) {
 	if w.conn.hijacked {
-		log.Stderr("http: response.WriteHeader on hijacked connection")
+		log.Print("http: response.WriteHeader on hijacked connection")
 		return
 	}
 	if w.wroteHeader {
-		log.Stderr("http: multiple response.WriteHeader calls")
+		log.Print("http: multiple response.WriteHeader calls")
 		return
 	}
 	w.wroteHeader = true
@@ -248,7 +248,7 @@ func (w *response) WriteHeader(code int) {
 // Write implements the ResponseWriter.Write method
 func (w *response) Write(data []byte) (n int, err os.Error) {
 	if w.conn.hijacked {
-		log.Stderr("http: response.Write on hijacked connection")
+		log.Print("http: response.Write on hijacked connection")
 		return 0, ErrHijacked
 	}
 	if !w.wroteHeader {
@@ -721,7 +721,7 @@ func ListenAndServe(addr string, handler Handler) os.Error {
 //
 //	func main() {
 //		http.HandleFunc("/", handler)
-//		log.Stdoutf("About to listen on 10443. Go to https://127.0.0.1:10443/")
+//		log.Printf("About to listen on 10443. Go to https://127.0.0.1:10443/")
 //		err := http.ListenAndServeTLS(":10443", "cert.pem", "key.pem", nil)
 //		if err != nil {
 //			log.Exit(err)