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Diffstat (limited to 'sys/tty/ttysubi.x')
| -rw-r--r-- | sys/tty/ttysubi.x | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/sys/tty/ttysubi.x b/sys/tty/ttysubi.x new file mode 100644 index 00000000..870dce59 --- /dev/null +++ b/sys/tty/ttysubi.x @@ -0,0 +1,194 @@ +# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc. + +include <chars.h> +include <ctype.h> +include "tty.h" + +.help ttysubi +.nf ___________________________________________________________________________ +TTYSUBI -- Argument substitution on a control string. + + Process a capability string containing arguments. Examples of such +capability strings are cursor motion to [x,y], and set scrolling region to +[line1,line2]. Note that arguments in the termcap database are zero-indexed +by default, while the TTYSUBI arguments are one-indexed. The control string +given as input has already been processed to reduce all escape sequences to +single characters. + +Various output formats are supported (some of these are completely off the +wall, very special case, but that's how termcap does it): + + %d print decimal integer, zero origin. + %2 like %2d. + %3 like %3d. + %. put binary value of x,y arg as a character + %+x like %., but add value of char X first + %% print a single %. + +The following format codes affect the arguments, but do not directly cause +any output: + + %>xy if next arg value > char x add char y. + %r reverses order of arguments. + %i increments arg values by one, for 1 origin. + %n exlusive-or args with 0140B. (DM2500) + %B BCD next arg, (16*(x/10))+(mod(x,10). + %D Reverse coding (x-2*(mod(x,16))). (Delta Data) + +We have generalized the termcap formats somewhat to permit a greater range +of %n formats (%1-%4), as well as %o and %x formats, in case a terminal +comes along which likes octal or hex numbers. + +The %. format causes special problems. If the terminal requires coordinates +in binary in the range zero or one to 40B, we can expect problems trying to +push such chars through the OS driver and any other software (networks, etc.), +since system software likes to map control characters on output. To get around +this we have defined a set of reserved codes which are not to be generated. +This set is defined in tty.h, and includes newline, tab, etc. When asked to +output one of these chars, we output a char with a somewhat larger value +and return the delta to our caller, which does whatever is appropriate to +complete the function. +.endhelp ______________________________________________________________________ + +int procedure ttysubi (ctrlstr, outstr, maxch, coords, ncoords) + +char ctrlstr[ARB] # control string containing % formats +char outstr[ARB] # receives processed string +int maxch +int coords[ncoords] # on input, coords; on output, deltas +int ncoords + +bool reverse # reverse deltas on output +int revstart # first arg/coord reversed +int args[MAX_COORDS] # processed values of arguments +int argnum # arg being processed +int nargs # number of args (min(MAX_COORDS,ncoords)) +char driver_chars[NDCHARS] +char ch, format_char +int i, ip, op, field_width, left, right, temp +int stridx(), strlen(), xor() +data driver_chars /DRIVER_CHARS/ +errchk sprintf, pargi + +begin + # Make a local copy of the arguments to make reversal etc. easy. + # Also switch to zero-indexing internally, since the termcap entry + # is zero-indexed. + + nargs = min (MAX_COORDS, ncoords) + do i = 1, nargs { + args[i] = coords[i] - 1 # make zero-indexed + coords[i] = 0 # init delta + } + argnum = 1 # output x first by default + reverse = false + + op = 1 + for (ip=1; ctrlstr[ip] != EOS && op <= maxch; ip=ip+1) { + ch = ctrlstr[ip] + + # If normal char, we do not get past this if statement. + if (ch != '%') { + outstr[op] = ch + op = op + 1 + next + } else { + ip = ip + 1 # fetch format-type char + ch = ctrlstr[ip] + } + + # Get here only if processing a %x format specification. + switch (ch) { + case '%': # %% --> % + outstr[op] = ch + op = op + 1 + + case 'd', 'o', 'x', '1', '2', '3', '4': + # Output next argument according to the format given. + if (IS_DIGIT(ch)) { + field_width = TO_INTEG(ch) + format_char = 'd' + } else { + field_width = 0 + format_char = ch + } + + call sprintf (outstr[op], maxch-op+1, "%0*.0*") + call pargi (field_width) + call pargc (format_char) + call pargi (args[argnum]) + + argnum = min (nargs, argnum + 1) + op = op + strlen (outstr[op]) + + case '.', '+': + # Binary output format. Coordinate output in binary is a + # problem because the OS driver may see a tab, newline, or + # whatever and map it into something else. If the value of + # args[argnum] corresponds to a special control character, + # we increment it until we have an acceptable value, leaving + # it up to our caller to do the rest. + + if (ch == '+') { + ip = ip + 1 + args[argnum] = args[argnum] + ctrlstr[ip] + } + + repeat { + ch = char (args[argnum]) + if (stridx (ch, driver_chars) > 0) { + args[argnum] = args[argnum] + 1 + coords[argnum] = coords[argnum] + 1 + } else + break + } + + outstr[op] = args[argnum] + op = op + 1 + argnum = min (nargs, argnum + 1) + + # The remaining cases are used to change the values of the + # remaining arguments, and do not cause any output. + + case '>': # %>xy + if (args[argnum] > ctrlstr[ip+1]) + args[argnum] = args[argnum] + ctrlstr[ip+2] + ip = ip + 2 + case 'r': # swap remaining args + do left = argnum, (nargs - argnum + 1) / 2 { + right = nargs - (left - argnum) + temp = args[left] + args[left] = args[right] + args[right] = temp + } + reverse = !reverse + revstart = argnum + case 'i': # increment by one + do i = argnum, nargs + args[i] = args[i] + 1 + case 'n': # exclusive or with 140B + do i = argnum, nargs + args[i] = xor (args[i], 140B) + case 'B': # BCD encode next arg + temp = args[argnum] + args[argnum] = 16 * (temp / 10) + mod (temp, 10) + case 'D': # Reverse code next arg + temp = args[argnum] + args[argnum] = temp - 2 * mod (temp, 16) + } + } + + # If the input coordinates were reversed, we must reverse the + # correction deltas, too. + + if (reverse) + do left = revstart, (nargs - revstart + 1) / 2 { + right = nargs - (left - revstart) + temp = coords[left] + coords[left] = coords[right] + coords[right] = temp + } + + outstr[op] = EOS + return (op - 1) +end |