/* $Id: term.c,v 1.255 2015/10/23 14:50:58 schwarze Exp $ */

/*

* Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>

* Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>

*

* Permission to use, copy, modify, and distribute this software for any

* purpose with or without fee is hereby granted, provided that the above

* copyright notice and this permission notice appear in all copies.

*

* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES

* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR

* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

*/

#include "config.h"

#include <sys/types.h>

#include <assert.h>

#include <ctype.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "mandoc.h"

#include "mandoc_aux.h"

#include "out.h"

#include "term.h"

#include "main.h"

static size_t cond_width(const struct termp *, int, int *);

static void adjbuf(struct termp *p, size_t);

static void bufferc(struct termp *, char);

static void encode(struct termp *, const char *, size_t);

static void encode1(struct termp *, int);

void

term_free(struct termp *p)

{

free(p->buf);

free(p->fontq);

free(p);

}

void

term_begin(struct termp *p, term_margin head,

term_margin foot, const struct roff_meta *arg)

{

p->headf = head;

p->footf = foot;

p->argf = arg;

(*p->begin)(p);

}

void

term_end(struct termp *p)

{

(*p->end)(p);

}

/*

* Flush a chunk of text. By default, break the output line each time

* the right margin is reached, and continue output on the next line

* at the same offset as the chunk itself. By default, also break the

* output line at the end of the chunk.

* The following flags may be specified:

*

* - TERMP_NOBREAK: Do not break the output line at the right margin,

* but only at the max right margin. Also, do not break the output

* line at the end of the chunk, such that the next call can pad to

* the next column. However, if less than p->trailspace blanks,

* which can be 0, 1, or 2, remain to the right margin, the line

* will be broken.

* - TERMP_BRTRSP: Consider trailing whitespace significant

* when deciding whether the chunk fits or not.

* - TERMP_BRIND: If the chunk does not fit and the output line has

* to be broken, start the next line at the right margin instead

* of at the offset. Used together with TERMP_NOBREAK for the tags

* in various kinds of tagged lists.

* - TERMP_DANGLE: Do not break the output line at the right margin,

* append the next chunk after it even if this one is too long.

* To be used together with TERMP_NOBREAK.

* - TERMP_HANG: Like TERMP_DANGLE, and also suppress padding before

* the next chunk if this column is not full.

*/

void

term_flushln(struct termp *p)

{

size_t i; /* current input position in p->buf */

int ntab; /* number of tabs to prepend */

size_t vis; /* current visual position on output */

size_t vbl; /* number of blanks to prepend to output */

size_t vend; /* end of word visual position on output */

size_t bp; /* visual right border position */

size_t dv; /* temporary for visual pos calculations */

size_t j; /* temporary loop index for p->buf */

size_t jhy; /* last hyph before overflow w/r/t j */

size_t maxvis; /* output position of visible boundary */

/*

* First, establish the maximum columns of "visible" content.

* This is usually the difference between the right-margin and

* an indentation, but can be, for tagged lists or columns, a

* small set of values.

*

* The following unsigned-signed subtractions look strange,

* but they are actually correct. If the int p->overstep

* is negative, it gets sign extended. Subtracting that

* very large size_t effectively adds a small number to dv.

*/

dv = p->rmargin > p->offset ? p->rmargin - p->offset : 0;

maxvis = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;

if (p->flags & TERMP_NOBREAK) {

dv = p->maxrmargin > p->offset ?

p->maxrmargin - p->offset : 0;

bp = (int)dv > p->overstep ?

dv - (size_t)p->overstep : 0;

} else

bp = maxvis;

/*

* Calculate the required amount of padding.

*/

vbl = p->offset + p->overstep > p->viscol ?

p->offset + p->overstep - p->viscol : 0;

vis = vend = 0;

i = 0;

while (i < p->col) {

/*

* Handle literal tab characters: collapse all

* subsequent tabs into a single huge set of spaces.

*/

ntab = 0;

while (i < p->col && '\t' == p->buf[i]) {

vend = (vis / p->tabwidth + 1) * p->tabwidth;

vbl += vend - vis;

vis = vend;

ntab++;

i++;

}

/*

* Count up visible word characters. Control sequences

* (starting with the CSI) aren't counted. A space

* generates a non-printing word, which is valid (the

* space is printed according to regular spacing rules).

*/

for (j = i, jhy = 0; j < p->col; j++) {

if (' ' == p->buf[j] || '\t' == p->buf[j])

break;

/* Back over the the last printed character. */

if (8 == p->buf[j]) {

assert(j);

vend -= (*p->width)(p, p->buf[j - 1]);

continue;

}

/* Regular word. */

/* Break at the hyphen point if we overrun. */

if (vend > vis && vend < bp &&

(ASCII_HYPH == p->buf[j] ||

ASCII_BREAK == p->buf[j]))

jhy = j;

/*

* Hyphenation now decided, put back a real

* hyphen such that we get the correct width.

*/

if (ASCII_HYPH == p->buf[j])

p->buf[j] = '-';

vend += (*p->width)(p, p->buf[j]);

}

/*

* Find out whether we would exceed the right margin.

* If so, break to the next line.

*/

if (vend > bp && 0 == jhy && vis > 0) {

vend -= vis;

(*p->endline)(p);

p->viscol = 0;

if (TERMP_BRIND & p->flags) {

vbl = p->rmargin;

vend += p->rmargin;

vend -= p->offset;

} else

vbl = p->offset;

/* use pending tabs on the new line */

if (0 < ntab)

vbl += ntab * p->tabwidth;

/*

* Remove the p->overstep width.

* Again, if p->overstep is negative,

* sign extension does the right thing.

*/

bp += (size_t)p->overstep;

p->overstep = 0;

}

/* Write out the [remaining] word. */

for ( ; i < p->col; i++) {

if (vend > bp && jhy > 0 && i > jhy)

break;

if ('\t' == p->buf[i])

break;

if (' ' == p->buf[i]) {

j = i;

while (i < p->col && ' ' == p->buf[i])

i++;

dv = (i - j) * (*p->width)(p, ' ');

vbl += dv;

vend += dv;

break;

}

if (ASCII_NBRSP == p->buf[i]) {

vbl += (*p->width)(p, ' ');

continue;

}

if (ASCII_BREAK == p->buf[i])

continue;

/*

* Now we definitely know there will be

* printable characters to output,

* so write preceding white space now.

*/

if (vbl) {

(*p->advance)(p, vbl);

p->viscol += vbl;

vbl = 0;

}

(*p->letter)(p, p->buf[i]);

if (8 == p->buf[i])

p->viscol -= (*p->width)(p, p->buf[i-1]);

else

p->viscol += (*p->width)(p, p->buf[i]);

}

vis = vend;

}

/*

* If there was trailing white space, it was not printed;

* so reset the cursor position accordingly.

*/

if (vis > vbl)

vis -= vbl;

else

vis = 0;

p->col = 0;

p->overstep = 0;

p->flags &= ~(TERMP_BACKAFTER | TERMP_BACKBEFORE);

if ( ! (TERMP_NOBREAK & p->flags)) {

p->viscol = 0;

(*p->endline)(p);

return;

}

if (TERMP_HANG & p->flags) {

p->overstep += (int)(p->offset + vis - p->rmargin +

p->trailspace * (*p->width)(p, ' '));

/*

* If we have overstepped the margin, temporarily move

* it to the right and flag the rest of the line to be

* shorter.

* If there is a request to keep the columns together,

* allow negative overstep when the column is not full.

*/

if (p->trailspace && p->overstep < 0)

p->overstep = 0;

return;

} else if (TERMP_DANGLE & p->flags)

return;

/* Trailing whitespace is significant in some columns. */

if (vis && vbl && (TERMP_BRTRSP & p->flags))

vis += vbl;

/* If the column was overrun, break the line. */

if (maxvis < vis + p->trailspace * (*p->width)(p, ' ')) {

(*p->endline)(p);

p->viscol = 0;

}

}

/*

* A newline only breaks an existing line; it won't assert vertical

* space. All data in the output buffer is flushed prior to the newline

* assertion.

*/

void

term_newln(struct termp *p)

{

p->flags |= TERMP_NOSPACE;

if (p->col || p->viscol)

term_flushln(p);

}

/*

* Asserts a vertical space (a full, empty line-break between lines).

* Note that if used twice, this will cause two blank spaces and so on.

* All data in the output buffer is flushed prior to the newline

* assertion.

*/

void

term_vspace(struct termp *p)

{

term_newln(p);

p->viscol = 0;

if (0 < p->skipvsp)

p->skipvsp--;

else

(*p->endline)(p);

}

/* Swap current and previous font; for \fP and .ft P */

void

term_fontlast(struct termp *p)

{

enum termfont f;

f = p->fontl;

p->fontl = p->fontq[p->fonti];

p->fontq[p->fonti] = f;

}

/* Set font, save current, discard previous; for \f, .ft, .B etc. */

void

term_fontrepl(struct termp *p, enum termfont f)

{

p->fontl = p->fontq[p->fonti];

p->fontq[p->fonti] = f;

}

/* Set font, save previous. */

void

term_fontpush(struct termp *p, enum termfont f)

{

p->fontl = p->fontq[p->fonti];

if (++p->fonti == p->fontsz) {

p->fontsz += 8;

p->fontq = mandoc_reallocarray(p->fontq,

p->fontsz, sizeof(enum termfont *));

}

p->fontq[p->fonti] = f;

}

/* Flush to make the saved pointer current again. */

void

term_fontpopq(struct termp *p, int i)

{

assert(i >= 0);

if (p->fonti > i)

p->fonti = i;

}

/* Pop one font off the stack. */

void

term_fontpop(struct termp *p)

{

assert(p->fonti);

p->fonti--;

}

/*

* Handle pwords, partial words, which may be either a single word or a

* phrase that cannot be broken down (such as a literal string). This

* handles word styling.

*/

void

term_word(struct termp *p, const char *word)

{

const char nbrsp[2] = { ASCII_NBRSP, 0 };

const char *seq, *cp;

int sz, uc;

size_t ssz;

enum mandoc_esc esc;

if ( ! (TERMP_NOSPACE & p->flags)) {

if ( ! (TERMP_KEEP & p->flags)) {

bufferc(p, ' ');

if (TERMP_SENTENCE & p->flags)

bufferc(p, ' ');

} else

bufferc(p, ASCII_NBRSP);

}

if (TERMP_PREKEEP & p->flags)

p->flags |= TERMP_KEEP;

if ( ! (p->flags & TERMP_NONOSPACE))

p->flags &= ~TERMP_NOSPACE;

else

p->flags |= TERMP_NOSPACE;

p->flags &= ~(TERMP_SENTENCE | TERMP_NONEWLINE);

p->skipvsp = 0;

while ('\0' != *word) {

if ('\\' != *word) {

if (TERMP_NBRWORD & p->flags) {

if (' ' == *word) {

encode(p, nbrsp, 1);

word++;

continue;

}

ssz = strcspn(word, "\\ ");

} else

ssz = strcspn(word, "\\");

encode(p, word, ssz);

word += (int)ssz;

continue;

}

word++;

esc = mandoc_escape(&word, &seq, &sz);

if (ESCAPE_ERROR == esc)

continue;

switch (esc) {

case ESCAPE_UNICODE:

uc = mchars_num2uc(seq + 1, sz - 1);

break;

case ESCAPE_NUMBERED:

uc = mchars_num2char(seq, sz);

if (uc < 0)

continue;

break;

case ESCAPE_SPECIAL:

if (p->enc == TERMENC_ASCII) {

cp = mchars_spec2str(seq, sz, &ssz);

if (cp != NULL)

encode(p, cp, ssz);

} else {

uc = mchars_spec2cp(seq, sz);

if (uc > 0)

encode1(p, uc);

}

continue;

case ESCAPE_FONTBOLD:

term_fontrepl(p, TERMFONT_BOLD);

continue;

case ESCAPE_FONTITALIC:

term_fontrepl(p, TERMFONT_UNDER);

continue;

case ESCAPE_FONTBI:

term_fontrepl(p, TERMFONT_BI);

continue;

case ESCAPE_FONT:

case ESCAPE_FONTROMAN:

term_fontrepl(p, TERMFONT_NONE);

continue;

case ESCAPE_FONTPREV:

term_fontlast(p);

continue;

case ESCAPE_NOSPACE:

if (p->flags & TERMP_BACKAFTER)

p->flags &= ~TERMP_BACKAFTER;

else if (*word == '\0')

p->flags |= (TERMP_NOSPACE | TERMP_NONEWLINE);

continue;

case ESCAPE_SKIPCHAR:

p->flags |= TERMP_BACKAFTER;

continue;

case ESCAPE_OVERSTRIKE:

cp = seq + sz;

while (seq < cp) {

if (*seq == '\\') {

mandoc_escape(&seq, NULL, NULL);

continue;

}

encode1(p, *seq++);

if (seq < cp) {

if (p->flags & TERMP_BACKBEFORE)

p->flags |= TERMP_BACKAFTER;

else

p->flags |= TERMP_BACKBEFORE;

}

}

/* Trim trailing backspace/blank pair. */

if (p->col > 2 && p->buf[p->col - 1] == ' ')

p->col -= 2;

continue;

default:

continue;

}

/*

* Common handling for Unicode and numbered

* character escape sequences.

*/

if (p->enc == TERMENC_ASCII) {

cp = ascii_uc2str(uc);

encode(p, cp, strlen(cp));

} else {

if ((uc < 0x20 && uc != 0x09) ||

(uc > 0x7E && uc < 0xA0))

uc = 0xFFFD;

encode1(p, uc);

}

}

p->flags &= ~TERMP_NBRWORD;

}

static void

adjbuf(struct termp *p, size_t sz)

{

if (0 == p->maxcols)

p->maxcols = 1024;

while (sz >= p->maxcols)

p->maxcols <<= 2;

p->buf = mandoc_reallocarray(p->buf, p->maxcols, sizeof(int));

}

static void

bufferc(struct termp *p, char c)

{

if (p->col + 1 >= p->maxcols)

adjbuf(p, p->col + 1);

p->buf[p->col++] = c;

}

/*

* See encode().

* Do this for a single (probably unicode) value.

* Does not check for non-decorated glyphs.

*/

static void

encode1(struct termp *p, int c)

{

enum termfont f;

if (p->col + 7 >= p->maxcols)

adjbuf(p, p->col + 7);

f = (c == ASCII_HYPH || c > 127 || isgraph(c)) ?

p->fontq[p->fonti] : TERMFONT_NONE;

if (p->flags & TERMP_BACKBEFORE) {

if (p->buf[p->col - 1] == ' ')

p->col--;

else

p->buf[p->col++] = 8;

p->flags &= ~TERMP_BACKBEFORE;

}

if (TERMFONT_UNDER == f || TERMFONT_BI == f) {

p->buf[p->col++] = '_';

p->buf[p->col++] = 8;

}

if (TERMFONT_BOLD == f || TERMFONT_BI == f) {

if (ASCII_HYPH == c)

p->buf[p->col++] = '-';

else

p->buf[p->col++] = c;

p->buf[p->col++] = 8;

}

p->buf[p->col++] = c;

if (p->flags & TERMP_BACKAFTER) {

p->flags |= TERMP_BACKBEFORE;

p->flags &= ~TERMP_BACKAFTER;

}

}

static void

encode(struct termp *p, const char *word, size_t sz)

{

size_t i;

if (p->col + 2 + (sz * 5) >= p->maxcols)

adjbuf(p, p->col + 2 + (sz * 5));

for (i = 0; i < sz; i++) {

if (ASCII_HYPH == word[i] ||

isgraph((unsigned char)word[i]))

encode1(p, word[i]);

else

p->buf[p->col++] = word[i];

}

}

void

term_setwidth(struct termp *p, const char *wstr)

{

struct roffsu su;

int iop, width;

iop = 0;

width = 0;

if (NULL != wstr) {

switch (*wstr) {

case '+':

iop = 1;

wstr++;

break;

case '-':

iop = -1;

wstr++;

break;

default:

break;

}

if (a2roffsu(wstr, &su, SCALE_MAX))

width = term_hspan(p, &su);

else

iop = 0;

}

(*p->setwidth)(p, iop, width);

}

size_t

term_len(const struct termp *p, size_t sz)

{

return (*p->width)(p, ' ') * sz;

}

static size_t

cond_width(const struct termp *p, int c, int *skip)

{

if (*skip) {

(*skip) = 0;

return 0;

} else

return (*p->width)(p, c);

}

size_t

term_strlen(const struct termp *p, const char *cp)

{

size_t sz, rsz, i;

int ssz, skip, uc;

const char *seq, *rhs;

enum mandoc_esc esc;

static const char rej[] = { '\\', ASCII_NBRSP, ASCII_HYPH,

ASCII_BREAK, '\0' };

/*

* Account for escaped sequences within string length

* calculations. This follows the logic in term_word() as we

* must calculate the width of produced strings.

*/

sz = 0;

skip = 0;

while ('\0' != *cp) {

rsz = strcspn(cp, rej);

for (i = 0; i < rsz; i++)

sz += cond_width(p, *cp++, &skip);

switch (*cp) {

case '\\':

cp++;

esc = mandoc_escape(&cp, &seq, &ssz);

if (ESCAPE_ERROR == esc)

continue;

rhs = NULL;

switch (esc) {

case ESCAPE_UNICODE:

uc = mchars_num2uc(seq + 1, ssz - 1);

break;

case ESCAPE_NUMBERED:

uc = mchars_num2char(seq, ssz);

if (uc < 0)

continue;

break;

case ESCAPE_SPECIAL:

if (p->enc == TERMENC_ASCII) {

rhs = mchars_spec2str(seq, ssz, &rsz);

if (rhs != NULL)

break;

} else {

uc = mchars_spec2cp(seq, ssz);

if (uc > 0)

sz += cond_width(p, uc, &skip);

}

continue;

case ESCAPE_SKIPCHAR:

skip = 1;

continue;

case ESCAPE_OVERSTRIKE:

rsz = 0;

rhs = seq + ssz;

while (seq < rhs) {

if (*seq == '\\') {

mandoc_escape(&seq, NULL, NULL);

continue;

}

i = (*p->width)(p, *seq++);

if (rsz < i)

rsz = i;

}

sz += rsz;

continue;

default:

continue;

}

/*

* Common handling for Unicode and numbered

* character escape sequences.

*/

if (rhs == NULL) {

if (p->enc == TERMENC_ASCII) {

rhs = ascii_uc2str(uc);

rsz = strlen(rhs);

} else {

if ((uc < 0x20 && uc != 0x09) ||

(uc > 0x7E && uc < 0xA0))

uc = 0xFFFD;

sz += cond_width(p, uc, &skip);

continue;

}

}

if (skip) {

skip = 0;

break;

}

/*

* Common handling for all escape sequences

* printing more than one character.

*/

for (i = 0; i < rsz; i++)

sz += (*p->width)(p, *rhs++);

break;

case ASCII_NBRSP:

sz += cond_width(p, ' ', &skip);

cp++;

break;

case ASCII_HYPH:

sz += cond_width(p, '-', &skip);

cp++;

break;

default:

break;

}

}

return sz;

}

int

term_vspan(const struct termp *p, const struct roffsu *su)

{

double r;

int ri;

switch (su->unit) {

case SCALE_BU:

r = su->scale / 40.0;

break;

case SCALE_CM:

r = su->scale * 6.0 / 2.54;

break;

case SCALE_FS:

r = su->scale * 65536.0 / 40.0;

break;

case SCALE_IN:

r = su->scale * 6.0;

break;

case SCALE_MM:

r = su->scale * 0.006;

break;

case SCALE_PC:

r = su->scale;

break;

case SCALE_PT:

r = su->scale / 12.0;

break;

case SCALE_EN:

case SCALE_EM:

r = su->scale * 0.6;

break;

case SCALE_VS:

r = su->scale;

break;

default:

abort();

}

ri = r > 0.0 ? r + 0.4995 : r - 0.4995;

return ri < 66 ? ri : 1;

}

/*

* Convert a scaling width to basic units, rounding down.

*/

int

term_hspan(const struct termp *p, const struct roffsu *su)

{

return (*p->hspan)(p, su);

}