Readline like input with persistent history

.gitignore

@@ -1,3 +1,4 @@
 bbz
 dist/
 firmware.o
+.bzzhistory

README.md

@@ -23,14 +23,16 @@ References:
 - [The MOS Reassembly for the BBC Micro](https://tobylobster.github.io/mos/mos/index.html)
 
 ## Features
-- Some of the MOS entrypoints and VDU control codes are defined.
 - Can run BBC BASIC and most of the language ROMs.
 - Can load up to 16 sideways ROMs.
+- Readline like input with persistent history (`-r` parameter)
+- Some of the MOS entrypoints and VDU control codes are defined.
 - Saves and loads files from the host filesystem.
 - Does some of the mode 7 text coloring using ANSI escape codes on the terminal. Try `VDU 65,129,66,130,67,132,68,135,69,13,10` on BBC BASIC.
 - OSCLI comands suported:
   - *QUIT: exit
   - *HELP
+  - *BASIC
   - *FX
   - *HOST cmd: execute a command on the host OS. Example: `*HOST ls -la`
 
@@ -50,6 +52,7 @@ AvaIlable flags (to put before the ROM filename if present):
   -c	dump to the console the CPU execution operations
   -m	dump to the console the MOS calls excluding console I/O calls
   -p	panic on not implemented MOS calls
+  -r	use readline like input with history
   -s	dump to the console the accesses to Fred, Jim or Sheila
   -rom0 string
     	filename for rom 0 (slot 0xf)

bbz.go

@@ -110,7 +110,7 @@ func RunMOS(env *environment) {
 					After an OSRDCH call: C=0 indicates that a valid character has
 					been read; C=1 flags an error condition, A contains an error number.
 				*/
-				ch, stop := env.in.readChar()
+				ch, stop := env.con.readChar()
 				if stop {
 					env.stop = true
 					return

console.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+type console interface {
+	readline() (string, bool)
+	readChar() (uint8, bool)
+	write(s string)
+	close()
+}
+
+type consoleSimple struct {
+	in *bufio.Scanner
+}
+
+func newConsoleSimple() *consoleSimple {
+	var c consoleSimple
+	c.in = bufio.NewScanner(os.Stdin)
+	return &c
+}
+
+func (c *consoleSimple) readline() (string, bool) {
+	if !c.in.Scan() {
+		return "", true
+	}
+	line := c.in.Text()
+	return line, false
+}
+
+func (c *consoleSimple) readChar() (uint8, bool) {
+	// TODO: capture keystrokes. We will just get the first char of the line
+	// and ignore the rest.
+	s, stop := c.readline()
+	if s == "" {
+		return ' ', stop
+	} else {
+		return s[0], stop
+	}
+}
+
+func (c *consoleSimple) write(s string) {
+	fmt.Print(s)
+}
+
+func (c *consoleSimple) close() {}

consoleLiner.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/peterh/liner"
+)
+
+const historyFilename = ".bzzhistory"
+
+type consoleLiner struct {
+	liner  *liner.State
+	prompt string
+}
+
+func newConsoleLiner() *consoleLiner {
+	var c consoleLiner
+
+	c.liner = liner.NewLiner()
+	c.liner.SetCtrlCAborts(true)
+	if f, err := os.Open(historyFilename); err == nil {
+		c.liner.ReadHistory(f)
+		f.Close()
+	}
+
+	return &c
+}
+
+func (c *consoleLiner) close() {
+
+	if f, err := os.Create(historyFilename); err == nil {
+		c.liner.WriteHistory(f)
+		f.Close()
+	}
+
+	c.liner.Close()
+}
+
+func (c *consoleLiner) readline() (string, bool) {
+	fmt.Printf("\r")
+	line, err := c.liner.Prompt(c.prompt)
+	c.prompt = ""
+	if err == liner.ErrPromptAborted || err == io.EOF {
+		return "", true
+	}
+	if err != nil {
+		panic(err)
+	}
+	c.liner.AppendHistory(line)
+	return line, false
+}
+
+func (c *consoleLiner) readChar() (uint8, bool) {
+	// TODO: capture keystrokes. We will just get the first char of the line
+	// and ignore the rest.
+	s, stop := c.readline()
+	if s == "" {
+		return ' ', stop
+	} else {
+		return s[0], stop
+	}
+}
+
+func (c *consoleLiner) write(s string) {
+	if strings.HasSuffix(s, "\n") || strings.HasSuffix(s, "\r") {
+		c.prompt = ""
+	} else {
+		c.prompt += s
+	}
+	fmt.Print(s)
+}

environment.go

@@ -12,7 +12,7 @@ type environment struct {
 	cpu *core6502.State
 	mem *acornMemory
 	vdu *vdu
-	in  input
+	con console
 
 	// clock, used by OSWORD01 and 02
 	referenceTime time.Time
@@ -33,22 +33,30 @@ type environment struct {
 	panicOnErr bool
 }
 
-func newEnvironment(cpuLog bool, apiLog bool, apiLogIO bool, memLog bool, panicOnErr bool) *environment {
+func newEnvironment(cpuLog bool, apiLog bool, apiLogIO bool, memLog bool, panicOnErr bool, readline bool) *environment {
 	var env environment
-	env.in = newInputSimple()
+	if readline {
+		env.con = newConsoleLiner()
+	} else {
+		env.con = newConsoleSimple()
+	}
 	env.referenceTime = time.Now()
 	env.timer = 0
 	env.lastTimerUpdate = time.Now()
 	env.mem = newAcornMemory(memLog)
 	env.cpu = core6502.NewNMOS6502(env.mem)
 	env.cpu.SetTrace(cpuLog)
-	env.vdu = newVdu()
+	env.vdu = newVdu(env.con)
 	env.apiLog = apiLog
 	env.apiLogIO = apiLogIO
 	env.panicOnErr = panicOnErr
 	return &env
 }
 
+func (env *environment) close() {
+	env.con.close()
+}
+
 func (env *environment) getFile(handle uint8) *os.File {
 	i := handle - 1
 	if i < maxFiles && env.file[i] != nil {

go.mod

@@ -2,5 +2,8 @@ module github.com/ivanizag/bbz
 
 go 1.16
 
-// Update with go get github.com/ivanizag/izapple2/core6502@master
-require github.com/ivanizag/izapple2 v0.0.0-20210725095035-e47730e13158
+require (
+	// Update with go get github.com/ivanizag/izapple2/core6502@master
+	github.com/ivanizag/izapple2 v0.0.0-20210725095035-e47730e13158
+	github.com/peterh/liner v1.2.1
+)

go.sum

@@ -19,8 +19,12 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/lucor/goinfo v0.0.0-20200401173949-526b5363a13a/go.mod h1:ORP3/rB5IsulLEBwQZCJyyV6niqmI7P4EWSmkug+1Ng=
+github.com/mattn/go-runewidth v0.0.3 h1:a+kO+98RDGEfo6asOGMmpodZq4FNtnGP54yps8BzLR4=
+github.com/mattn/go-runewidth v0.0.3/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
 github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
+github.com/peterh/liner v1.2.1 h1:O4BlKaq/LWu6VRWmol4ByWfzx6MfXc5Op5HETyIy5yg=
+github.com/peterh/liner v1.2.1/go.mod h1:CRroGNssyjTd/qIG2FyxByd2S8JEAZXBl4qUrZf8GS0=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/profile v1.5.0/go.mod h1:qBsxPvzyUincmltOk6iyRVxHYg4adc0OFOv72ZdLa18=

main.go

@@ -29,7 +29,10 @@ func main() {
 		"p",
 		false,
 		"panic on not implemented MOS calls")
-
+	readline := flag.Bool(
+		"r",
+		false,
+		"use readline like input with history")
 	roms := make([]*string, 16)
 	for i := 0; i < 16; i++ {
 		roms[i] = flag.String(
@@ -55,7 +58,9 @@ func main() {
 		(*traceMOS) || (*traceMOSFull),
 		*traceMOSFull,
 		*traceMemory,
-		*panicOnErr)
+		*panicOnErr,
+		*readline)
+	defer env.close()
 
 	env.mem.loadFirmware()
 

osWord.go

@@ -21,7 +21,7 @@ func execOSWORD(env *environment) {
 			line. C not equal to zero indicates that an escape condition terminated
 			entry. Y is set to the length of the line, excluding the CR if C=0.
 		*/
-		line, stop := env.in.readline()
+		line, stop := env.con.readline()
 		if stop {
 			env.stop = true
 			return

vdu.go

@@ -3,9 +3,9 @@ package main
 import "fmt"
 
 type vdu struct {
+	con   console
 	queue []uint8
-
-	mode uint8
+	mode  uint8
 
 	// Mode 0-6
 	textColour  uint8
@@ -25,7 +25,7 @@ type vdu struct {
 
 var argsNeeded [256]int
 
-func newVdu() *vdu {
+func newVdu(con console) *vdu {
 	// Init args needed array, 0 for all except:
 	argsNeeded[1] = 1
 	argsNeeded[17] = 1
@@ -41,6 +41,7 @@ func newVdu() *vdu {
 	argsNeeded[31] = 2
 
 	var v vdu
+	v.con = con
 	// Mode 7 on startup
 	v.mode = 7
 	v.m7fgColour = 7 // white
@@ -478,7 +479,7 @@ func (v *vdu) writeInternal(cmd uint8, q []uint8) {
 	}
 
 	if out != "" && !v.ignore {
-		fmt.Print(out)
+		v.con.write(out)
 	}
 }