Version 13 of Linux Console Text Editor In Pure TCL
Updated 2005-05-04 22:32:21 by JH2004-06-16 SRIV This is a minimal console text editor for Linux written in pure TCL.
Usage: con-editor.tcl filename After the file loads, the screen is blank till you hit the down arrow key, I forget why I did that. To save the file, press Ctrl-Q, it will prompt you to Save Y/n . Ctrl-Y will delete the current line.
I notice that the backspace key isn't working properly on my current computer, so I'll need to look into that. Update: backspace works at a true console, but misbehaves in an xterm. It also is fixed at 24x80, so the editor wont use more that that, like on a 50x132 framebuffer system.
Edited by JH 2005-05-04 to support any size terminal and clean up the code for improved readability. Anyone wanting to interpret more escape codes should find it easier to work with.
Screenshot:
#!/bin/sh
# The next line is executed by /bin/sh, but not tcl \
exec tclsh "$0" ${1+"$@"}
# con-editor.tcl a linux console based editor in pure tcl
# 2004-06-16 Steve Redler IV
# 2005-05-04 mods by Hobbs to work in any terminal size and clean up code
set filename [lindex $argv 0]
proc edittext {file2read visible} {
global CLEAR buffer HOME CURSOROFF CURSORON IDX
set COLUMN 1
set ROW 1
set lastrow ""
set lastcol ""
set firstcol2display ""
set firstrow2display ""
set line ""
set bufferrow 0
set buffercol 0
set char ""
puts -nonewline $CURSOROFF$HOME
while {$char != "\u0011"} {
set char [read $file2read 1]
if {[eof $file2read]} {return done}
switch -exact -- $char {
\u0011 { # ^q - quit
return done
}
\u0019 { # ^y - yank line
if {$bufferrow < [llength $buffer]} {
set buffer [lreplace $buffer $bufferrow $bufferrow]
set lastcol ""
}
}
\u000a { # ^j - insert last yank
set currline [string range $line 0 [expr {$buffercol - 1}]]
set buffer [lreplace $buffer $bufferrow $bufferrow $currline]
if {!$visible} {set IDX(ROW) $bufferrow}
incr bufferrow
incr ROW
set buffer [linsert $buffer $bufferrow \
[string range $line $buffercol end]]
set lastcol ""
set line [lindex $buffer $bufferrow]
set buffercol 0
}
\u001b { # ESC - handle escape sequences
set next [read stdin 1]
if {$next == "\["} { ; # \[
set next [read stdin 1]
switch -exact -- $next {
A { # Cursor Up (cuu1,up)
if {$bufferrow > 0} {incr bufferrow -1}
set line [lindex $buffer $bufferrow]
incr ROW -1
}
B { # Cursor Down
if {$bufferrow < [expr {[llength $buffer] -1}]} {
incr bufferrow 1
}
set line [lindex $buffer $bufferrow]
if {$bufferrow > [expr {$ROW -1}]} { incr ROW }
}
C { # Cursor Right (cuf1,nd)
if {$buffercol < [string length $line]} {
incr buffercol 1
}
}
D { # Cursor Left
if {$buffercol > 0} {incr buffercol -1 }
}
3 { # delete
set next [read stdin 1]
if {$buffercol > [string length $line]} {
set buffercol [string length $line]
}
set prevchr $buffercol
set line [string replace $line $prevchr $prevchr ""]
set buffer [lreplace $buffer $bufferrow $bufferrow $line]
set lastcol ""
}
}
}
}
\u007f { # backspace ?
if {$buffercol != 0} {
if {$buffercol > [string length $line]} {
set buffercol [string length $line]
}
set prevchr [expr {$buffercol - 1}]
set line [string replace $line $prevchr $prevchr ""]
incr buffercol -1
}
set buffer [lreplace $buffer $bufferrow $bufferrow $line]
set lastcol ""
}
default {
if {$char == "\u0009"} { # ^i - insert tab space (4 spaces)
set char " "
}
append newline [string range $line 0 [expr {$buffercol - 1}]] \
$char [string range $line $buffercol end]
set line $newline
set newline ""
set buffer [lreplace $buffer $bufferrow $bufferrow $line]
incr buffercol [string length $char]
if {$buffercol > [string length $line]} {
set buffercol [string length $line]
}
set lastcol ""
}
}
if {$visible} {
if {$ROW <= 1} {set ROW 1}
if {$ROW >= ($IDX(ROWMAX) - 1)} {set ROW [expr {$IDX(ROWMAX) - 1}]}
set COLUMN [expr {$buffercol + 1}]
if {$COLUMN <= 1} {set COLUMN 1}
if {$COLUMN >= $IDX(COLMAX)} {set COLUMN $IDX(COLMAX)}
puts -nonewline $CURSOROFF$HOME
set firstrow2display [expr {$bufferrow - $ROW +1}]
set lastrow2display [expr {$firstrow2display + $IDX(ROWMAX) - 1}]
set firstcol2display [expr {$buffercol - $COLUMN +1}]
set lastcol2display [expr {$firstcol2display + $IDX(COLMAX) - 1}]
if {($lastrow != $firstrow2display)
|| ($lastcol != $firstcol2display)} {
for {set i $firstrow2display} {$i < $lastrow2display} {incr i} {
puts -nonewline "\u001b\[K"
puts [string range [lindex $buffer $i] $firstcol2display $lastcol2display ]
}
}
set lastrow $firstrow2display
set lastcol $firstcol2display
set IDX(ROW) [expr {$bufferrow +1}]
set IDX(COL) [expr {$buffercol +1}]
idx $IDX(ROW) $IDX(COL)
puts -nonewline "\u001b\[${ROW};${COLUMN}H"
puts -nonewline $CURSORON
flush stdout
}
}
}
proc status {msg} {
global IDX
set len [expr {$IDX(ROWCOL) - 1}]
set str [format "%-${len}.${len}s" $msg]
puts -nonewline "\u001b\[$IDX(ROWMAX);00H$str"
}
proc idx {row col} {
global IDX
set len $IDX(ROWCOLLEN)
set str [format "%-${len}.${len}s" "LINE:$row COL:$col"]
puts -nonewline "\u001b\[$IDX(ROWMAX);$IDX(ROWCOL)H$str"
}
#start of console editor program
#puts -nonewline $CLEAR
proc console_edit {fileName} {
global CLEAR buffer HOME CURSOROFF CURSORON IDX
#Script-Edit by Steve Redler IV [email protected] 5-30-2001
set IDX(ROWMAX) 24
set IDX(COLMAX) 80
if {![catch {exec stty -a} err]
&& [regexp {rows (\d+); columns (\d+)} $err -> rows cols]} {
set IDX(ROWMAX) $rows
set IDX(COLMAX) $cols
}
set IDX(ROWCOLLEN) 15
set IDX(ROWCOL) [expr {$IDX(COLMAX) - $IDX(ROWCOLLEN)}]
set CLEAR "\u001b\[2J" ; # \u001b == ESC
set buffer [list {}]
set HOME "\u001b\[1;1H"
set CURSORON "\u001b\[?[expr {$IDX(ROWMAX)+1}]h"
set CURSOROFF "\u001b\[?[expr {$IDX(ROWMAX)+1}]l"
set infile [open $fileName RDWR]
edittext $infile 0
close $infile
puts -nonewline $CLEAR$HOME$CURSORON
status "\u0007$fileName loaded"
idx $IDX(ROW) 1
fconfigure stdin -buffering none -blocking 1
fconfigure stdout -translation crlf
flush stdout
exec stty raw -echo
edittext stdin 1
status "Save '$fileName'? Y/n"
flush stdout
#fconfigure stdin -buffering full -blocking 1
set line [read stdin 1]
exec stty -raw echo
if {$line != "n"} {
set outfile [open $fileName w ]
puts "len of buffer [llength $buffer]"
for {set i 0} {$i<[llength $buffer]} {incr i} {
puts $outfile [lindex $buffer $i]
#puts [lindex $buffer $i]
}
close $outfile
status " Saved"
} else {
status " Aborted"
}
puts -nonewline $CLEAR$HOME
exit 0
}
console_edit $filename