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/* lpovrtyp.c */
/* Copyright 1995 by Steve Kirkendall */
char id_lpovrtyp[] = "$Id: lpovrtyp.c,v 2.11 1996/07/11 15:33:20 steve Exp $";
/* This file contains a driver for printer types which use overtyping to
* simulate fonts. There are two styles: "cr" uses a single carriage return
* to start overtyping a whole line, and "bs" uses backspace to overtype a
* single character. Some line printers refuse to backspace more than /n/
* times per line; they like the "cr" style. On the other hand, "bs" is more
* like the output produced by /nroff/, and the /more/ program understands it.
*/
#include "elvis.h"
#if USE_PROTOTYPES
static void outcr(void);
static void outbs(void);
static void before(int minorno, void (*draw)(_CHAR_));
static void fontch(_char_ font, _CHAR_ ch);
static void page(int linesleft);
static void after(int linesleft);
#endif
/* This value is the minor number of the driver being used. It is set by the
* before() function, and remains valid until the after() function returns.
* It should be 0 for "cr", or 1 for "bs".
*/
static int ptype;
/* This is a pointer to the draw() function to use for outputing individual
* characters. It is set by the before() function, and remains valid until
* the after() function returns.
*/
static void (*prtchar) P_((_CHAR_ ch));
/* These are a line buffer. Each character in the line can have 2 parts,
* and we also remember the length of the line. part1 is always filled.
* part2 may be partially filled, if some characters are normal. In this
* case, the length2 indicates the portion of the part2 which has been used.
*/
static CHAR *part1, *part2;
static int column, length2;
/* This function outputs the buffered line using the "cr" technique. */
static void outcr()
{
int i;
/* output part1 */
for (i = 0; i < column; i++)
{
(*prtchar)(part1[i]);
}
/* if there is a part2, then output a CR and then part2 */
if (length2 > 0)
{
(*prtchar)('\r');
for (i = 0; i < length2; i++)
{
(*prtchar)(part2[i]);
}
}
}
/* This function outputs the buffered line using the "bs" technique */
static void outbs()
{
int i;
/* output each column's pair of characters */
for (i = 0; i < column; i++)
{
(*prtchar)(part1[i]);
if (part2[i] != ' ')
{
(*prtchar)('\b');
(*prtchar)(part2[i]);
}
}
}
/* This is the before() function. It sets the ptype index, and allocates a
* line buffer. Also, if the lpcolumns option is unset, then this sets it to
* 132 because the cr/bs driver can't handle lines of unknown length.
*/
static void before(minorno, draw)
int minorno; /* which style of control codes to use */
void (*draw) P_((_CHAR_)); /* function for sending single char to printer */
{
assert(minorno == 0 || minorno == 1);
/* set the ptype and out function */
ptype = minorno;
prtchar = draw;
/* if lpcolumns is unset, then set it to 132 */
if (o_lpcolumns == 0)
{
o_lpcolumns = 132;
}
/* allocate storage space for the line buffer */
part1 = (CHAR *)safealloc((int)o_lpcolumns, sizeof(CHAR));
part2 = (CHAR *)safealloc((int)o_lpcolumns, sizeof(CHAR));
column = length2 = 0;
}
/* This function adds a character to the line buffer, or if the character is
* a control character then it outputs the line and then the control character
*/
static void fontch(font, ch)
_char_ font; /* font of the next character from text image */
_CHAR_ ch; /* the next character */
{
switch (ch)
{
case '\n':
case '\f':
/* output the line */
switch (ptype)
{
case 0: outcr(); break;
case 1: outbs(); break;
}
/* output the character. formfeed implies CR */
(*prtchar)(ch);
if (ch == '\f')
{
(*prtchar)('\r');
}
/* get ready for next line */
column = length2 = 0;
break;
default:
assert(column < o_lpcolumns);
switch (font)
{
case 'i':
case 'u':
part1[column] = '_';
part2[column] = ch;
length2 = ++column;
break;
case 'b':
case 'e':
part1[column] = part2[column] = ch;
length2 = ++column;
break;
case 'g':
if (ch >= '1' && ch <= '9')
{
ch = '+';
}
part1[column] = ch;
part2[column] = ' ';
++column;
break;
default:
part1[column] = ch;
part2[column] = ' ';
++column;
}
}
}
/* This function is called after every page except the last one */
static void page(linesleft)
int linesleft; /* lines remaining on page */
{
/* output a formfeed character */
if (linesleft > 0)
{
(*prtchar)('\f');
}
}
/* This function is called at the end of the print job. It can output a
* final formfeed, restore fonts, or whatever. Here, it just frees the
* line buffer.
*/
static void after(linesleft)
int linesleft; /* lines remaining on final page */
{
safefree(part1);
safefree(part2);
if (o_lpformfeed)
{
(*prtchar)((_CHAR_)'\f');
}
}
/* These describe the printer types supported by these functions */
LPTYPE lpcr = {"cr", 0, True, before, fontch, page, after};
LPTYPE lpbs = {"bs", 1, True, before, fontch, page, after};
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.