1 /* $Id: term.c,v 1.120 2009/10/31 06:10:58 kristaps Exp $ */
3 * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@kth.se>
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
30 /* FIXME: accomodate non-breaking, non-collapsing white-space. */
31 /* FIXME: accomodate non-breaking, collapsing white-space. */
33 static struct termp
*term_alloc(enum termenc
);
34 static void term_free(struct termp
*);
36 static void do_escaped(struct termp
*, const char **);
37 static void do_special(struct termp
*,
38 const char *, size_t);
39 static void do_reserved(struct termp
*,
40 const char *, size_t);
41 static void buffer(struct termp
*, char);
42 static void encode(struct termp
*, char);
49 return(term_alloc(TERMENC_ASCII
));
54 terminal_free(void *arg
)
57 term_free((struct termp
*)arg
);
62 term_free(struct termp
*p
)
68 chars_free(p
->symtab
);
75 term_alloc(enum termenc enc
)
79 p
= calloc(1, sizeof(struct termp
));
91 * Flush a line of text. A "line" is loosely defined as being something
92 * that should be followed by a newline, regardless of whether it's
93 * broken apart by newlines getting there. A line can also be a
94 * fragment of a columnar list.
96 * Specifically, a line is whatever's in p->buf of length p->col, which
97 * is zeroed after this function returns.
99 * The usage of termp:flags is as follows:
101 * - TERMP_NOLPAD: when beginning to write the line, don't left-pad the
102 * offset value. This is useful when doing columnar lists where the
103 * prior column has right-padded.
105 * - TERMP_NOBREAK: this is the most important and is used when making
106 * columns. In short: don't print a newline and instead pad to the
107 * right margin. Used in conjunction with TERMP_NOLPAD.
109 * - TERMP_TWOSPACE: when padding, make sure there are at least two
110 * space characters of padding. Otherwise, rather break the line.
112 * - TERMP_DANGLE: don't newline when TERMP_NOBREAK is specified and
113 * the line is overrun, and don't pad-right if it's underrun.
115 * - TERMP_HANG: like TERMP_DANGLE, but doesn't newline when
116 * overruning, instead save the position and continue at that point
117 * when the next invocation.
119 * In-line line breaking:
121 * If TERMP_NOBREAK is specified and the line overruns the right
122 * margin, it will break and pad-right to the right margin after
123 * writing. If maxrmargin is violated, it will break and continue
124 * writing from the right-margin, which will lead to the above scenario
125 * upon exit. Otherwise, the line will break at the right margin.
128 term_flushln(struct termp
*p
)
130 int i
; /* current input position in p->buf */
131 size_t vis
; /* current visual position on output */
132 size_t vbl
; /* number of blanks to prepend to output */
133 size_t vsz
; /* visual characters to write to output */
134 size_t bp
; /* visual right border position */
135 int j
; /* temporary loop index */
137 static int overstep
= 0;
140 * First, establish the maximum columns of "visible" content.
141 * This is usually the difference between the right-margin and
142 * an indentation, but can be, for tagged lists or columns, a
143 * small set of values.
146 assert(p
->offset
< p
->rmargin
);
148 maxvis
= (int)(p
->rmargin
- p
->offset
) - overstep
< 0 ?
150 0 : p
->rmargin
- p
->offset
- overstep
;
151 mmax
= (int)(p
->maxrmargin
- p
->offset
) - overstep
< 0 ?
153 0 : p
->maxrmargin
- p
->offset
- overstep
;
155 bp
= TERMP_NOBREAK
& p
->flags
? mmax
: maxvis
;
158 * FIXME: if bp is zero, we still output the first word before
165 * If in the standard case (left-justified), then begin with our
166 * indentation, otherwise (columns, etc.) just start spitting
170 if ( ! (p
->flags
& TERMP_NOLPAD
))
172 for (j
= 0; j
< (int)p
->offset
; j
++)
175 for (i
= 0; i
< (int)p
->col
; i
++) {
177 * Count up visible word characters. Control sequences
178 * (starting with the CSI) aren't counted. A space
179 * generates a non-printing word, which is valid (the
180 * space is printed according to regular spacing rules).
184 for (j
= i
, vsz
= 0; j
< (int)p
->col
; j
++) {
185 if (j
&& ' ' == p
->buf
[j
])
187 else if (8 == p
->buf
[j
])
194 * Choose the number of blanks to prepend: no blank at the
195 * beginning of a line, one between words -- but do not
196 * actually write them yet.
198 vbl
= (size_t)(0 == vis
? 0 : 1);
201 * Find out whether we would exceed the right margin.
202 * If so, break to the next line. (TODO: hyphenate)
203 * Otherwise, write the chosen number of blanks now.
205 if (vis
&& vis
+ vbl
+ vsz
> bp
) {
207 if (TERMP_NOBREAK
& p
->flags
) {
208 for (j
= 0; j
< (int)p
->rmargin
; j
++)
210 vis
= p
->rmargin
- p
->offset
;
212 for (j
= 0; j
< (int)p
->offset
; j
++)
216 /* Remove the overstep width. */
217 bp
+= (int)/* LINTED */
221 for (j
= 0; j
< (int)vbl
; j
++)
227 * Finally, write out the word.
229 for ( ; i
< (int)p
->col
; i
++) {
230 if (' ' == p
->buf
[i
])
240 if ( ! (TERMP_NOBREAK
& p
->flags
)) {
245 if (TERMP_HANG
& p
->flags
) {
246 /* We need one blank after the tag. */
247 overstep
= /* LINTED */
251 * Behave exactly the same way as groff:
252 * If we have overstepped the margin, temporarily move
253 * it to the right and flag the rest of the line to be
255 * If we landed right at the margin, be happy.
256 * If we are one step before the margin, temporarily
257 * move it one step LEFT and flag the rest of the line
260 if (overstep
>= -1) {
261 assert((int)maxvis
+ overstep
>= 0);
267 } else if (TERMP_DANGLE
& p
->flags
)
271 if (maxvis
> vis
+ /* LINTED */
272 ((TERMP_TWOSPACE
& p
->flags
) ? 1 : 0))
273 for ( ; vis
< maxvis
; vis
++)
275 else { /* ...or newline break. */
277 for (i
= 0; i
< (int)p
->rmargin
; i
++)
284 * A newline only breaks an existing line; it won't assert vertical
285 * space. All data in the output buffer is flushed prior to the newline
289 term_newln(struct termp
*p
)
292 p
->flags
|= TERMP_NOSPACE
;
294 p
->flags
&= ~TERMP_NOLPAD
;
298 p
->flags
&= ~TERMP_NOLPAD
;
303 * Asserts a vertical space (a full, empty line-break between lines).
304 * Note that if used twice, this will cause two blank spaces and so on.
305 * All data in the output buffer is flushed prior to the newline
309 term_vspace(struct termp
*p
)
318 do_special(struct termp
*p
, const char *word
, size_t len
)
324 rhs
= chars_a2ascii(p
->symtab
, word
, len
, &sz
);
328 fputs("Unknown special character: ", stderr
);
329 for (i
= 0; i
< (int)len
; i
++)
330 fputc(word
[i
], stderr
);
335 for (i
= 0; i
< (int)sz
; i
++)
341 do_reserved(struct termp
*p
, const char *word
, size_t len
)
347 rhs
= chars_a2res(p
->symtab
, word
, len
, &sz
);
351 fputs("Unknown reserved word: ", stderr
);
352 for (i
= 0; i
< (int)len
; i
++)
353 fputc(word
[i
], stderr
);
358 for (i
= 0; i
< (int)sz
; i
++)
364 * Handle an escape sequence: determine its length and pass it to the
365 * escape-symbol look table. Note that we assume mdoc(3) has validated
366 * the escape sequence (we assert upon badly-formed escape sequences).
369 do_escaped(struct termp
*p
, const char **word
)
384 if (0 == *wp
|| 0 == *(wp
+ 1)) {
385 *word
= 0 == *wp
? wp
: wp
+ 1;
389 do_special(p
, wp
, 2);
393 } else if ('*' == *wp
) {
402 if (0 == *wp
|| 0 == *(wp
+ 1)) {
403 *word
= 0 == *wp
? wp
: wp
+ 1;
407 do_reserved(p
, wp
, 2);
414 do_reserved(p
, wp
, 1);
419 } else if ('f' == *wp
) {
435 p
->bold
= p
->under
= 0;
444 } else if ('[' != *wp
) {
445 do_special(p
, wp
, 1);
451 for (j
= 0; *wp
&& ']' != *wp
; wp
++, j
++)
460 do_special(p
, wp
- j
, (size_t)j
);
462 do_reserved(p
, wp
- j
, (size_t)j
);
468 * Handle pwords, partial words, which may be either a single word or a
469 * phrase that cannot be broken down (such as a literal string). This
470 * handles word styling.
473 term_word(struct termp
*p
, const char *word
)
479 if (word
[0] && 0 == word
[1])
498 if ( ! (TERMP_IGNDELIM
& p
->flags
))
499 p
->flags
|= TERMP_NOSPACE
;
505 if ( ! (TERMP_NOSPACE
& p
->flags
))
508 if ( ! (p
->flags
& TERMP_NONOSPACE
))
509 p
->flags
&= ~TERMP_NOSPACE
;
511 for ( ; *word
; word
++)
515 do_escaped(p
, &word
);
517 if (sv
[0] && 0 == sv
[1])
524 p
->flags
|= TERMP_NOSPACE
;
533 * Insert a single character into the line-buffer. If the buffer's
534 * space is exceeded, then allocate more space by doubling the buffer
538 buffer(struct termp
*p
, char c
)
542 if (p
->col
+ 1 >= p
->maxcols
) {
546 p
->buf
= realloc(p
->buf
, s
);
547 if (NULL
== p
->buf
) {
553 p
->buf
[(int)(p
->col
)++] = c
;
558 encode(struct termp
*p
, char c
)
576 term_vspan(const struct roffsu
*su
)
594 r
= su
->scale
/ 1000;
606 return(/* LINTED */(size_t)
612 term_hspan(const struct roffsu
*su
)
616 /* XXX: CM, IN, and PT are approximations. */
623 /* XXX: this is an approximation. */
627 r
= (10 * su
->scale
) / 6;
630 r
= (10 * su
->scale
) / 72;
633 r
= su
->scale
/ 1000; /* FIXME: double-check. */
636 r
= su
->scale
* 2 - 1; /* FIXME: double-check. */
645 return((size_t)/* LINTED */