/* Id: term.c,v 1.283 2021/08/10 12:55:04 schwarze Exp */

/* Id: term.c,v 1.283 2021/08/10 12:55:04 schwarze Exp */
/*
* Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <[email protected]>
* Copyright (c) 2010-2020 Ingo Schwarze <[email protected]>
*
* 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 <stdint.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_col *, size_t);
static void bufferc(struct termp *, char);
static void encode(struct termp *, const char *, size_t);
static void encode1(struct termp *, int);
static void endline(struct termp *);
static void term_field(struct termp *, size_t, size_t);
static void term_fill(struct termp *, size_t *, size_t *,
size_t);

void
term_setcol(struct termp *p, size_t maxtcol)
{
if (maxtcol > p->maxtcol) {
p->tcols = mandoc_recallocarray(p->tcols,
p->maxtcol, maxtcol, sizeof(*p->tcols));
p->maxtcol = maxtcol;
}
p->lasttcol = maxtcol - 1;
p->tcol = p->tcols;
}

void
term_free(struct termp *p)
{
for (p->tcol = p->tcols; p->tcol < p->tcols + p->maxtcol; p->tcol++)
free(p->tcol->buf);
free(p->tcols);
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. There are many flags modifying
* this behaviour, see the comments in the body of the function.
*/
void
term_flushln(struct termp *p)
{
size_t vbl; /* Number of blanks to prepend to the output. */
size_t vbr; /* Actual visual position of the end of field. */
size_t vfield; /* Desired visual field width. */
size_t vtarget; /* Desired visual position of the right margin. */
size_t ic; /* Character position in the input buffer. */
size_t nbr; /* Number of characters to print in this field. */

/*
* Normally, start writing at the left margin, but with the
* NOPAD flag, start writing at the current position instead.
*/

vbl = (p->flags & TERMP_NOPAD) || p->tcol->offset < p->viscol ?
0 : p->tcol->offset - p->viscol;
if (p->minbl && vbl < p->minbl)
vbl = p->minbl;

if ((p->flags & TERMP_MULTICOL) == 0)
p->tcol->col = 0;

/* Loop over output lines. */

for (;;) {
vfield = p->tcol->rmargin > p->viscol + vbl ?
p->tcol->rmargin - p->viscol - vbl : 0;

/*
* Normally, break the line at the the right margin
* of the field, but with the NOBREAK flag, only
* break it at the max right margin of the screen,
* and with the BRNEVER flag, never break it at all.
*/

vtarget = (p->flags & TERMP_NOBREAK) == 0 ? vfield :
p->maxrmargin > p->viscol + vbl ?
p->maxrmargin - p->viscol - vbl : 0;

/*
* Figure out how much text will fit in the field.
* If there is whitespace only, print nothing.
*/

term_fill(p, &nbr, &vbr,
p->flags & TERMP_BRNEVER ? SIZE_MAX : vtarget);
if (nbr == 0)
break;

/*
* With the CENTER or RIGHT flag, increase the indentation
* to center the text between the left and right margins
* or to adjust it to the right margin, respectively.
*/

if (vbr < vtarget) {
if (p->flags & TERMP_CENTER)
vbl += (vtarget - vbr) / 2;
else if (p->flags & TERMP_RIGHT)
vbl += vtarget - vbr;
}

/* Finally, print the field content. */

term_field(p, vbl, nbr);

/*
* If there is no text left in the field, exit the loop.
* If the BRTRSP flag is set, consider trailing
* whitespace significant when deciding whether
* the field fits or not.
*/

for (ic = p->tcol->col; ic < p->tcol->lastcol; ic++) {
switch (p->tcol->buf[ic]) {
case '\t':
if (p->flags & TERMP_BRTRSP)
vbr = term_tab_next(vbr);
continue;
case ' ':
if (p->flags & TERMP_BRTRSP)
vbr += (*p->width)(p, ' ');
continue;
case '\n':
case ASCII_BREAK:
continue;
default:
break;
}
break;
}
if (ic == p->tcol->lastcol)
break;

/*
* At the location of an automtic line break, input
* space characters are consumed by the line break.
*/

while (p->tcol->col < p->tcol->lastcol &&
p->tcol->buf[p->tcol->col] == ' ')
p->tcol->col++;

/*
* In multi-column mode, leave the rest of the text
* in the buffer to be handled by a subsequent
* invocation, such that the other columns of the
* table can be handled first.
* In single-column mode, simply break the line.
*/

if (p->flags & TERMP_MULTICOL)
return;

endline(p);
p->viscol = 0;

/*
* Normally, start the next line at the same indentation
* as this one, but with the BRIND flag, start it at the
* right margin instead. This is used together with
* NOBREAK for the tags in various kinds of tagged lists.
*/

vbl = p->flags & TERMP_BRIND ?
p->tcol->rmargin : p->tcol->offset;
}

/* Reset output state in preparation for the next field. */

p->col = p->tcol->col = p->tcol->lastcol = 0;
p->minbl = p->trailspace;
p->flags &= ~(TERMP_BACKAFTER | TERMP_BACKBEFORE | TERMP_NOPAD);

if (p->flags & TERMP_MULTICOL)
return;

/*
* The HANG flag means that the next field
* always follows on the same line.
* The NOBREAK flag means that the next field
* follows on the same line unless the field was overrun.
* Normally, break the line at the end of each field.
*/

if ((p->flags & TERMP_HANG) == 0 &&
((p->flags & TERMP_NOBREAK) == 0 ||
vbr + term_len(p, p->trailspace) > vfield))
endline(p);
}

/*
* Store the number of input characters to print in this field in *nbr
* and their total visual width to print in *vbr.
* If there is only whitespace in the field, both remain zero.
* The desired visual width of the field is provided by vtarget.
* If the first word is longer, the field will be overrun.
*/
static void
term_fill(struct termp *p, size_t *nbr, size_t *vbr, size_t vtarget)
{
size_t ic; /* Character position in the input buffer. */
size_t vis; /* Visual position of the current character. */
size_t vn; /* Visual position of the next character. */
int breakline; /* Break at the end of this word. */
int graph; /* Last character was non-blank. */

*nbr = *vbr = vis = 0;
breakline = graph = 0;
for (ic = p->tcol->col; ic < p->tcol->lastcol; ic++) {
switch (p->tcol->buf[ic]) {
case '\b': /* Escape \o (overstrike) or backspace markup. */
assert(ic > 0);
vis -= (*p->width)(p, p->tcol->buf[ic - 1]);
continue;

case '\t': /* Normal ASCII whitespace. */
case ' ':
case ASCII_BREAK: /* Escape \: (breakpoint). */
switch (p->tcol->buf[ic]) {
case '\t':
vn = term_tab_next(vis);
break;
case ' ':
vn = vis + (*p->width)(p, ' ');
break;
case ASCII_BREAK:
vn = vis;
break;
default:
abort();
}
/* Can break at the end of a word. */
if (breakline || vn > vtarget)
break;
if (graph) {
*nbr = ic;
*vbr = vis;
graph = 0;
}
vis = vn;
continue;

case '\n': /* Escape \p (break at the end of the word). */
breakline = 1;
continue;

case ASCII_HYPH: /* Breakable hyphen. */
graph = 1;
/*
* We are about to decide whether to break the
* line or not, so we no longer need this hyphen
* to be marked as breakable. Put back a real
* hyphen such that we get the correct width.
*/
p->tcol->buf[ic] = '-';
vis += (*p->width)(p, '-');
if (vis > vtarget) {
ic++;
break;
}
*nbr = ic + 1;
*vbr = vis;
continue;

case ASCII_NBRSP: /* Non-breakable space. */
p->tcol->buf[ic] = ' ';
/* FALLTHROUGH */
default: /* Printable character. */
graph = 1;
vis += (*p->width)(p, p->tcol->buf[ic]);
if (vis > vtarget && *nbr > 0)
return;
continue;
}
break;
}

/*
* If the last word extends to the end of the field without any
* trailing whitespace, the loop could not check yet whether it
* can remain on this line. So do the check now.
*/

if (graph && (vis <= vtarget || *nbr == 0)) {
*nbr = ic;
*vbr = vis;
}
}

/*
* Print the contents of one field
* with an indentation of vbl visual columns,
* and an input string length of nbr characters.
*/
static void
term_field(struct termp *p, size_t vbl, size_t nbr)
{
size_t ic; /* Character position in the input buffer. */
size_t vis; /* Visual position of the current character. */
size_t dv; /* Visual width of the current character. */
size_t vn; /* Visual position of the next character. */

vis = 0;
for (ic = p->tcol->col; ic < nbr; ic++) {

/*
* To avoid the printing of trailing whitespace,
* do not print whitespace right away, only count it.
*/

switch (p->tcol->buf[ic]) {
case '\n':
case ASCII_BREAK:
continue;
case '\t':
vn = term_tab_next(vis);
vbl += vn - vis;
vis = vn;
continue;
case ' ':
case ASCII_NBRSP:
dv = (*p->width)(p, ' ');
vbl += dv;
vis += dv;
continue;
default:
break;
}

/*
* We found a non-blank character to print,
* so write preceding white space now.
*/

if (vbl > 0) {
(*p->advance)(p, vbl);
p->viscol += vbl;
vbl = 0;
}

/* Print the character and adjust the visual position. */

(*p->letter)(p, p->tcol->buf[ic]);
if (p->tcol->buf[ic] == '\b') {
dv = (*p->width)(p, p->tcol->buf[ic - 1]);
p->viscol -= dv;
vis -= dv;
} else {
dv = (*p->width)(p, p->tcol->buf[ic]);
p->viscol += dv;
vis += dv;
}
}
p->tcol->col = nbr;
}

static void
endline(struct termp *p)
{
if ((p->flags & (TERMP_NEWMC | TERMP_ENDMC)) == TERMP_ENDMC) {
p->mc = NULL;
p->flags &= ~TERMP_ENDMC;
}
if (p->mc != NULL) {
if (p->viscol && p->maxrmargin >= p->viscol)
(*p->advance)(p, p->maxrmargin - p->viscol + 1);
p->flags |= TERMP_NOBUF | TERMP_NOSPACE;
term_word(p, p->mc);
p->flags &= ~(TERMP_NOBUF | TERMP_NEWMC);
}
p->viscol = 0;
p->minbl = 0;
(*p->endline)(p);
}

/*
* 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->tcol->lastcol || 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;
p->minbl = 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(*p->fontq));
}
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)
{
struct roffsu su;
const char nbrsp[2] = { ASCII_NBRSP, 0 };
const char *seq, *cp;
int sz, uc;
size_t csz, lsz, ssz;
enum mandoc_esc esc;

if ((p->flags & TERMP_NOBUF) == 0) {
if ((p->flags & TERMP_NOSPACE) == 0) {
if ((p->flags & TERMP_KEEP) == 0) {
bufferc(p, ' ');
if (p->flags & TERMP_SENTENCE)
bufferc(p, ' ');
} else
bufferc(p, ASCII_NBRSP);
}
if (p->flags & TERMP_PREKEEP)
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);
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_UNDEF:
uc = *seq;
break;
case ESCAPE_FONTBOLD:
case ESCAPE_FONTCB:
term_fontrepl(p, TERMFONT_BOLD);
continue;
case ESCAPE_FONTITALIC:
case ESCAPE_FONTCI:
term_fontrepl(p, TERMFONT_UNDER);
continue;
case ESCAPE_FONTBI:
term_fontrepl(p, TERMFONT_BI);
continue;
case ESCAPE_FONT:
case ESCAPE_FONTCR:
case ESCAPE_FONTROMAN:
term_fontrepl(p, TERMFONT_NONE);
continue;
case ESCAPE_FONTPREV:
term_fontlast(p);
continue;
case ESCAPE_BREAK:
bufferc(p, '\n');
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_DEVICE:
if (p->type == TERMTYPE_PDF)
encode(p, "pdf", 3);
else if (p->type == TERMTYPE_PS)
encode(p, "ps", 2);
else if (p->enc == TERMENC_ASCII)
encode(p, "ascii", 5);
else
encode(p, "utf8", 4);
continue;
case ESCAPE_HORIZ:
if (*seq == '|') {
seq++;
uc = -p->col;
} else
uc = 0;
if (a2roffsu(seq, &su, SCALE_EM) == NULL)
continue;
uc += term_hen(p, &su);
if (uc > 0)
while (uc-- > 0)
bufferc(p, ASCII_NBRSP);
else if (p->col > (size_t)(-uc))
p->col += uc;
else {
uc += p->col;
p->col = 0;
if (p->tcol->offset > (size_t)(-uc)) {
p->ti += uc;
p->tcol->offset += uc;
} else {
p->ti -= p->tcol->offset;
p->tcol->offset = 0;
}
}
continue;
case ESCAPE_HLINE:
if ((cp = a2roffsu(seq, &su, SCALE_EM)) == NULL)
continue;
uc = term_hen(p, &su);
if (uc <= 0) {
if (p->tcol->rmargin <= p->tcol->offset)
continue;
lsz = p->tcol->rmargin - p->tcol->offset;
} else
lsz = uc;
if (*cp == seq[-1])
uc = -1;
else if (*cp == '\\') {
seq = cp + 1;
esc = mandoc_escape(&seq, &cp, &sz);
switch (esc) {
case ESCAPE_UNICODE:
uc = mchars_num2uc(cp + 1, sz - 1);
break;
case ESCAPE_NUMBERED:
uc = mchars_num2char(cp, sz);
break;
case ESCAPE_SPECIAL:
uc = mchars_spec2cp(cp, sz);
break;
case ESCAPE_UNDEF:
uc = *seq;
break;
default:
uc = -1;
break;
}
} else
uc = *cp;
if (uc < 0x20 || (uc > 0x7E && uc < 0xA0))
uc = '_';
if (p->enc == TERMENC_ASCII) {
cp = ascii_uc2str(uc);
csz = term_strlen(p, cp);
ssz = strlen(cp);
} else
csz = (*p->width)(p, uc);
while (lsz >= csz) {
if (p->enc == TERMENC_ASCII)
encode(p, cp, ssz);
else
encode1(p, uc);
lsz -= csz;
}
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->tcol->lastcol > 2 &&
(p->tcol->buf[p->tcol->lastcol - 1] == ' ' ||
p->tcol->buf[p->tcol->lastcol - 1] == '\t'))
p->tcol->lastcol -= 2;
if (p->col > p->tcol->lastcol)
p->col = p->tcol->lastcol;
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_col *c, size_t sz)
{
if (c->maxcols == 0)
c->maxcols = 1024;
while (c->maxcols <= sz)
c->maxcols <<= 2;
c->buf = mandoc_reallocarray(c->buf, c->maxcols, sizeof(*c->buf));
}

static void
bufferc(struct termp *p, char c)
{
if (p->flags & TERMP_NOBUF) {
(*p->letter)(p, c);
return;
}
if (p->col + 1 >= p->tcol->maxcols)
adjbuf(p->tcol, p->col + 1);
if (p->tcol->lastcol <= p->col || (c != ' ' && c != ASCII_NBRSP))
p->tcol->buf[p->col] = c;
if (p->tcol->lastcol < ++p->col)
p->tcol->lastcol = p->col;
}

/*
* 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->flags & TERMP_NOBUF) {
(*p->letter)(p, c);
return;
}

if (p->col + 7 >= p->tcol->maxcols)
adjbuf(p->tcol, p->col + 7);

f = (c == ASCII_HYPH || c > 127 || isgraph(c)) ?
p->fontq[p->fonti] : TERMFONT_NONE;

if (p->flags & TERMP_BACKBEFORE) {
if (p->tcol->buf[p->col - 1] == ' ' ||
p->tcol->buf[p->col - 1] == '\t')
p->col--;
else
p->tcol->buf[p->col++] = '\b';
p->flags &= ~TERMP_BACKBEFORE;
}
if (f == TERMFONT_UNDER || f == TERMFONT_BI) {
p->tcol->buf[p->col++] = '_';
p->tcol->buf[p->col++] = '\b';
}
if (f == TERMFONT_BOLD || f == TERMFONT_BI) {
if (c == ASCII_HYPH)
p->tcol->buf[p->col++] = '-';
else
p->tcol->buf[p->col++] = c;
p->tcol->buf[p->col++] = '\b';
}
if (p->tcol->lastcol <= p->col || (c != ' ' && c != ASCII_NBRSP))
p->tcol->buf[p->col] = c;
if (p->tcol->lastcol < ++p->col)
p->tcol->lastcol = p->col;
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->flags & TERMP_NOBUF) {
for (i = 0; i < sz; i++)
(*p->letter)(p, word[i]);
return;
}

if (p->col + 2 + (sz * 5) >= p->tcol->maxcols)
adjbuf(p->tcol, 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 {
if (p->tcol->lastcol <= p->col ||
(word[i] != ' ' && word[i] != ASCII_NBRSP))
p->tcol->buf[p->col] = word[i];
p->col++;

/*
* Postpone the effect of \z while handling
* an overstrike sequence from ascii_uc2str().
*/

if (word[i] == '\b' &&
(p->flags & TERMP_BACKBEFORE)) {
p->flags &= ~TERMP_BACKBEFORE;
p->flags |= TERMP_BACKAFTER;
}
}
}
if (p->tcol->lastcol < p->col)
p->tcol->lastcol = p->col;
}

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) != NULL)
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++;
rhs = NULL;
esc = mandoc_escape(&cp, &seq, &ssz);
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_UNDEF:
uc = *seq;
break;
case ESCAPE_DEVICE:
if (p->type == TERMTYPE_PDF) {
rhs = "pdf";
rsz = 3;
} else if (p->type == TERMTYPE_PS) {
rhs = "ps";
rsz = 2;
} else if (p->enc == TERMENC_ASCII) {
rhs = "ascii";
rsz = 5;
} else {
rhs = "utf8";
rsz = 4;
}
break;
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 towards 0.
*/
int
term_hspan(const struct termp *p, const struct roffsu *su)
{

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

/*
* Convert a scaling width to basic units, rounding to closest.
*/
int
term_hen(const struct termp *p, const struct roffsu *su)
{
int bu;

if ((bu = (*p->hspan)(p, su)) >= 0)
return (bu + 11) / 24;
else
return -((-bu + 11) / 24);
}