From: Sergey Matveev <stargrave@stargrave.org>
Date: Sun, 20 Dec 2015 15:50:41 +0000 (+0300)
Subject: Pretty output printer
X-Git-Tag: v0.1.0~9
X-Git-Url: http://www.git.stargrave.org/?p=syncer.git;a=commitdiff_plain;h=116f382ec640820a94cbb37c0ad3b933d4bfd48a

Pretty output printer
---

diff --git a/printer.go b/printer.go
new file mode 100644
index 0000000..0313d61
--- /dev/null
+++ b/printer.go
@@ -0,0 +1,69 @@
+/*
+syncer -- stateful file/device data syncer.
+Copyright (C) 2015-2016 Sergey Matveev <stargrave@stargrave.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import (
+	"fmt"
+	"strconv"
+)
+
+const (
+	BufLine       = 80
+	CharChanged   = byte('%')
+	CharUnchanged = byte('.')
+)
+
+type Printer struct {
+	i       int64
+	total   int64
+	changed int64
+	frmt    string
+	bufSize int
+	outBuf  []byte
+}
+
+func NewPrinter(total int64) *Printer {
+	p := Printer{total: total}
+	maxLen := len(fmt.Sprintf("%d", total))
+	p.frmt = "%" + strconv.Itoa(maxLen) + "d/%d %02d%% %s\n"
+	p.bufSize = BufLine - (2*maxLen + 6)
+	p.outBuf = make([]byte, 0, p.bufSize)
+	return &p
+}
+
+func (p *Printer) Changed() {
+	p.i++
+	p.changed++
+	p.outBuf = append(p.outBuf, CharChanged)
+	p.Output()
+}
+
+func (p *Printer) Unchanged() {
+	p.i++
+	p.outBuf = append(p.outBuf, CharUnchanged)
+	p.Output()
+}
+
+func (p *Printer) Output() {
+	if !(len(p.outBuf) == p.bufSize || p.i == p.total) {
+		return
+	}
+	fmt.Printf(p.frmt, p.i, p.total, 100*p.changed/p.i, string(p.outBuf))
+	p.outBuf = p.outBuf[:0]
+}
diff --git a/syncer.go b/syncer.go
index 3a9e68a..dc48314 100644
--- a/syncer.go
+++ b/syncer.go
@@ -1,6 +1,6 @@
 /*
 syncer -- stateful file/device data syncer.
-Copyright (C) 2015 Sergey Matveev <stargrave@stargrave.org>
+Copyright (C) 2015-2016 Sergey Matveev <stargrave@stargrave.org>
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -45,11 +45,6 @@ type SyncEvent struct {
 	data []byte
 }
 
-func prn(s string) {
-	os.Stdout.Write([]byte(s))
-	os.Stdout.Sync()
-}
-
 func main() {
 	flag.Parse()
 	bs := *blkSize * int64(1<<10)
@@ -155,7 +150,7 @@ func main() {
 	syncs := make(chan chan SyncEvent, workers)
 
 	// Writer
-	prn("[")
+	prn := NewPrinter(blocks)
 	finished := make(chan struct{})
 	go func() {
 		var event SyncEvent
@@ -188,10 +183,10 @@ func main() {
 			sumState := state[i*blake2b.Size : i*blake2b.Size+blake2b.Size]
 			if bytes.Compare(sumState, sum[:]) != 0 {
 				sync <- SyncEvent{i, buf, buf[:n]}
-				prn("%")
+				prn.Changed()
 			} else {
 				sync <- SyncEvent{i, buf, nil}
-				prn(".")
+				prn.Unchanged()
 			}
 			copy(sumState, sum[:])
 			close(sync)
@@ -199,7 +194,7 @@ func main() {
 	}
 	close(syncs)
 	<-finished
-	prn("]\n")
+	prn.Output()
 
 	log.Println("Saving state")
 	stateFile.Write(state)