############################################################################ # # File: itlibdos.icn # # Subject: Procedures for MS-DOS termlib-type tools # # Author: Richard L. Goerwitz # # Date: August 14, 1996 # ############################################################################ # # This file is in the public domain. # ############################################################################ # # Version: 1.15 # ############################################################################ # # The following library represents a series of rough functional # equivalents to the standard UNIX low-level termcap routines. They # are not meant as exact termlib clones. Nor are they enhanced to # take care of magic cookie terminals, terminals that use \D in their # termcap entries, or, in short, anything I felt would not affect my # normal, day-to-day work with ANSI and vt100 terminals. At this # point I'd recommend trying iolib.icn instead of itlibdos.icn. Iolib # is largely DOS-UNIX interchangeable, and it does pretty much every- # thing itlibdos.icn does. # ############################################################################ # # Requires: An MS-DOS platform & co-expressions. The MS-DOS version # is a port of the UNIX version. Software you write for this library # can be made to run under UNIX simply by substituting the UNIX ver- # sion of this library. See below for additional notes on how to use # this MS-DOS port. # # setname(term) # Use only if you wish to initialize itermlib for a terminal # other than what your current environment specifies. "Term" is the # name of the termcap entry to use. Normally this initialization is # done automatically, and need not concern the user. # # getval(id) # Works something like tgetnum, tgetflag, and tgetstr. In the # spirit of Icon, all three have been collapsed into one routine. # Integer valued caps are returned as integers, strings as strings, # and flags as records (if a flag is set, then type(flag) will return # "true"). Absence of a given capability is signalled by procedure # failure. # # igoto(cm,destcol,destline) - NB: default 1 offset (*not* zero)! # Analogous to tgoto. "Cm" is the cursor movement command for # the current terminal, as obtained via getval("cm"). Igoto() # returns a string which, when output via iputs, will cause the # cursor to move to column "destcol" and line "destline." Column and # line are always calculated using a *one* offset. This is far more # Iconish than the normal zero offset used by tgoto. If you want to # go to the first square on your screen, then include in your program # "iputs(igoto(getval("cm"),1,1))." # # iputs(cp,affcnt) # Equivalent to tputs. "Cp" is a string obtained via getval(), # or, in the case of "cm," via igoto(getval("cm"),x,y). Affcnt is a # count of affected lines. It is only relevant for terminals which # specify proportional (starred) delays in their termcap entries. # ############################################################################ # # Notes on the MS-DOS version: # There are two basic reasons for using the I/O routines # contained in this package. First, by using a set of generalized # routines, your code will become much more readable. Secondly, by # using a high level interface, you can avoid the cardinal # programming error of hard coding things like screen length and # escape codes into your programs. # To use this collection of programs, you must do two things. # First, you must add the line "device=ansi.sys" (or the name of some # other driver, like zansi.sys, nansi.sys, or nnansi.sys [=new # nansi.sys]) to your config.sys file. Secondly, you must add two # lines to your autoexec.bat file: 1) "set TERM=ansi-mono" and 2) # "set TERMCAP=\location\termcap." The purpose of setting the TERM # variable is to tell this program what driver you are using. If you # have a color system, use "ansi-color" instead of "ansi-mono," and # if you are using nansi or zansi instead of vanilla ansi, use one of # these names instead of the "ansi" (e.g. "zansi-mono"). The purpose # of setting TERMCAP is to make it possible to determine where the # termcap file is located. The termcap file (which should have been # packed with this library as termcap.dos) is a short database of all # the escape sequences used by the various terminal drivers. Set # TERMCAP so that it reflects the location of this file (which should # be renamed as termcap, for the sake of consistency with the UNIX # version). Naturally, you must change "\location\" above to reflect # the correct path on your system. With some distributions, a second # termcap file may be included (termcap2.dos). Certain games work a # lot better using this alternate file. To try it out, rename it to # termcap, and set TERMCAP to its location. # Although I make no pretense here of providing here a complete # introduction to the format of the termcap database file, it will be # useful, I think, to explain a few basic facts about how to use this # program in conjunction with it. If, say, you want to clear the # screen, add the line, # # iputs(getval("cl")) # # to your program. The function iputs() outputs screen control # sequences. Getval retrieves a specific sequence from the termcap # file. The string "cl" is the symbol used in the termcap file to # mark the code used to clear the screen. By executing the # expression "iputs(getval("cl"))," you are 1) looking up the "cl" # (clear) code in the termcap database entry for your terminal, and # the 2) outputting that sequence to the screen. # Some other useful termcap symbols are "ce" (clear to end of # line), "ho" (go to the top left square on the screen), "so" (begin # standout mode), and "se" (end standout mode). To output a # boldfaced string, str, to the screen, you would write - # # iputs(getval("so")) # writes(str) # iputs(getval("se")) # # You could write "writes(getval("so") || str || getval("se")), but # this would only work for DOS. Some UNIX terminals require padding, # and iputs() handles them specially. Normally you should not worry # about UNIX quirks under DOS. It is in general wise, though, to # separate out screen control sequences, and output them via iputs(). # It is also heartily to be recommended that MS-DOS programmers # try not to assume that everyone will be using a 25-line screen. # Some terminals are 24-line. Some 43. Some have variable window # sizes. If you want to put a status line on, say, the 2nd-to-last # line of the screen, then determine what that line is by executing # "getval("li")." The termcap database holds not only string-valued # sequences, but numeric ones as well. The value of "li" tells you # how many lines the terminal has (compare "co," which will tell you # how many columns). To go to the beginning of the second-to-last # line on the screen, type in: # # iputs(igoto(getval("cm"), 1, getval("li")-1)) # # The "cm" capability is a special capability, and needs to be output # via igoto(cm,x,y), where cm is the sequence telling your computer # to move the cursor to a specified spot, x is the column, and y is # the row. The expression "getval("li")-1" will return the number of # the second-to-last line on your screen. # ############################################################################ # # Requires: MS-DOS, coexpressions # ############################################################################ # # See also: iscreen.icn, iolib.icn, itlib.icn # ############################################################################ global tc_table record true() procedure check_features() local in_params, line initial { find("ms-dos",map(&features)) | er("check_features","MS-DOS system required",1) find("o-expres",&features) | er("check_features","co-expressions not implemented - &$#!",1) } return end procedure setname(name) # Sets current terminal type to "name" and builds a new termcap # capability database (residing in tc_table). Fails if unable to # find a termcap entry for terminal type "name." If you want it # to terminate with an error message under these circumstances, # comment out "| fail" below, and uncomment the er() line. #tc_table is global check_features() tc_table := maketc_table(getentry(name)) | fail # er("setname","no termcap entry found for "||name,3) return end procedure getname() # Getname() first checks to be sure we're running under DOS, and, # if so, tries to figure out what the current terminal type is, # checking the value of the environment variable TERM, and if this # is unsuccessful, defaulting to "mono." local term, tset_output check_features() term := getenv("TERM") | "mono" return \term | er("getname","can't seem to determine your terminal type",1) end procedure er(func,msg,errnum) # short error processing utility write(&errout,func,": ",msg) exit(errnum) end procedure getentry(name, termcap_string) # "Name" designates the current terminal type. Getentry() scans # the current environment for the variable TERMCAP. If the # TERMCAP string represents a termcap entry for a terminal of type # "name," then getentry() returns the TERMCAP string. Otherwise, # getentry() will check to see if TERMCAP is a file name. If so, # getentry() will scan that file for an entry corresponding to # "name." If the TERMCAP string does not designate a filename, # getentry() will look through ./termcap for the correct entry. # Whatever the input file, if an entry for terminal "name" is # found, getentry() returns that entry. Otherwise, getentry() # fails. local f, getline, line, nm, ent1, ent2, entry /termcap_string := getenv("TERMCAP") if \termcap_string ? (not match("\\"), pos(1) | tab(find("|")+1), =name) then return termcap_string else { # The logic here probably isn't clear. The idea is to try to use # the termcap environment variable successively as 1) a termcap en- # try and then 2) as a termcap file. If neither works, 3) go to # the ./termcap file. The else clause here does 2 and, if ne- # cessary, 3. The "\termcap_string ? (not match..." expression # handles 1. if find("\\",\termcap_string) then f := open(termcap_string) /f := open("termcap") | er("getentry","I can't access your termcap file",1) getline := create read_file(f) while line := @getline do { if line ? (pos(1) | tab(find("|")+1), =name, any(':|')) then { entry := "" while (\line | @getline) ? { if entry ||:= 1(tab(find(":")+1), pos(0)) then { close(f) # if entry ends in tc= then add in the named tc entry entry ?:= tab(find("tc=")) || # recursively fetch the new termcap entry (move(3), getentry(tab(find(":"))) ? # remove the name field from the new entry (tab(find(":")+1), tab(0))) return entry } else { \line := &null # must precede the next line entry ||:= trim(trim(tab(0),'\\'),':') } } } } } close(f) er("getentry","can't find and/or process your termcap entry",3) end procedure read_file(f) # Suspends all non #-initial lines in the file f. # Removes leading tabs and spaces from lines before suspending # them. local line \f | er("read_tcap_file","no valid termcap file found",3) while line := read(f) do { match("#",line) & next line ?:= (tab(many('\t ')) | &null, tab(0)) suspend line } fail end procedure maketc_table(entry) # Maketc_table(s) (where s is a valid termcap entry for some # terminal-type): Returns a table in which the keys are termcap # capability designators, and the values are the entries in # "entry" for those designators. local k, v /entry & er("maketc_table","no entry given",8) if entry[-1] ~== ":" then entry ||:= ":" tc_table := table() entry ? { tab(find(":")+1) # tab past initial (name) field while tab((find(":")+1) \ 1) ? { &subject == "" & next if k := 1(move(2), ="=") then tc_table[k] := Decode(tab(find(":"))) else if k := 1(move(2), ="#") then tc_table[k] := integer(tab(find(":"))) else if k := 1(tab(find(":")), pos(-1)) then tc_table[k] := true() else er("maketc_table", "your termcap file has a bad entry",3) } } return tc_table end procedure getval(id) /tc_table := maketc_table(getentry(getname())) | er("getval","can't make a table for your terminal",4) return \tc_table[id] | fail # er("getval","the current terminal doesn't support "||id,7) end procedure Decode(s) local new_s, chr, chr2 # Does things like turn ^ plus a letter into a genuine control # character. new_s := "" s ? { while new_s ||:= tab(upto('\\^')) do { chr := move(1) if chr == "\\" then { new_s ||:= { case chr2 := move(1) of { "\\" : "\\" "^" : "^" "E" : "\e" "b" : "\b" "f" : "\f" "n" : "\n" "r" : "\r" "t" : "\t" default : { if any(&digits,chr2) then { char(integer("8r"||chr2||move(2 to 0 by -1))) | er("Decode","bad termcap entry",3) } else chr2 } } } } else new_s ||:= char(ord(map(move(1),&lcase,&ucase)) - 64) } new_s ||:= tab(0) } return new_s end procedure igoto(cm,col,line) local colline, range, increment, padding, str, outstr, chr, x, y if col > (tc_table["co"]) | line > (tc_table["li"]) then { colline := string(\col) || "," || string(\line) | string(\col|line) range := "(" || tc_table["co"]-1 || "," || tc_table["li"]-1 || ")" er("igoto",colline || " out of range " || (\range|""),9) } # Use the Iconish 1;1 upper left corner & not the C-ish 0 offsets increment := -1 outstr := "" cm ? { while outstr ||:= tab(find("%")) do { tab(match("%")) if padding := integer(tab(any('23'))) then chr := (="d" | "d") else chr := move(1) if case \chr of { "." : outstr ||:= char(line + increment) "+" : outstr ||:= char(line + ord(move(1)) + increment) "d" : { str := string(line + increment) outstr ||:= right(str, \padding, "0") | str } } then line :=: col else { case chr of { "n" : line := ixor(line,96) & col := ixor(col,96) "i" : increment := 0 "r" : line :=: col "%" : outstr ||:= "%" "B" : line := ior(ishift(line / 10, 4), line % 10) ">" : { x := move(1); y := move(1) line > ord(x) & line +:= ord(y) &null } } | er("goto","bad termcap entry",5) } } return outstr || tab(0) } end procedure iputs(cp, affcnt) # Writes cp to the screen. Use this instead of writes() for # compatibility with the UNIX version (which will need to send # null padding in some cases). Iputs() also does a useful type # check. static num_chars initial num_chars := &digits ++ '.' type(cp) == "string" | er("iputs","you can't iputs() a non-string value!",10) cp ? { if tab(many(num_chars)) & ="*" then stop("iputs: MS-DOS termcap files shouldn't specify padding.") writes(tab(0)) } return end