+ p->headf = head;
+ p->footf = foot;
+ p->argf = arg;
+ (*p->begin)(p);
+}
+
+
+void
+term_end(struct termp *p)
+{
+
+ (*p->end)(p);
+}
+
+/*
+ * Flush a line of text. A "line" is loosely defined as being something
+ * that should be followed by a newline, regardless of whether it's
+ * broken apart by newlines getting there. A line can also be a
+ * fragment of a columnar list (`Bl -tag' or `Bl -column'), which does
+ * not have a trailing newline.
+ *
+ * The following flags may be specified:
+ *
+ * - TERMP_NOBREAK: this is the most important and is used when making
+ * columns. In short: don't print a newline and instead expect the
+ * next call to do the padding up to the start of the next column.
+ *
+ * - TERMP_TWOSPACE: make sure there is room for at least two space
+ * characters of padding. Otherwise, rather break the line.
+ *
+ * - TERMP_DANGLE: don't newline when TERMP_NOBREAK is specified and
+ * the line is overrun, and don't pad-right if it's underrun.
+ *
+ * - TERMP_HANG: like TERMP_DANGLE, but doesn't newline when
+ * overrunning, instead save the position and continue at that point
+ * when the next invocation.
+ *
+ * In-line line breaking:
+ *
+ * If TERMP_NOBREAK is specified and the line overruns the right
+ * margin, it will break and pad-right to the right margin after
+ * writing. If maxrmargin is violated, it will break and continue
+ * writing from the right-margin, which will lead to the above scenario
+ * upon exit. Otherwise, the line will break at the right margin.
+ */
+void
+term_flushln(struct termp *p)
+{
+ int i; /* current input position in p->buf */
+ 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 */
+ int j; /* temporary loop index for p->buf */
+ int jhy; /* last hyph before overflow w/r/t j */
+ size_t maxvis; /* output position of visible boundary */
+ size_t mmax; /* used in calculating bp */
+
+ /*
+ * 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.
+ */
+ assert (p->rmargin >= p->offset);
+ dv = p->rmargin - p->offset;
+ maxvis = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
+ dv = p->maxrmargin - p->offset;
+ mmax = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
+
+ bp = TERMP_NOBREAK & p->flags ? mmax : 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.
+ */
+ while (i < p->col && '\t' == p->buf[i]) {
+ vend = (vis / p->tabwidth + 1) * p->tabwidth;
+ vbl += vend - vis;
+ vis = vend;
+ 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 ((j && ' ' == 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])
+ jhy = 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_NOBREAK & p->flags) {
+ vbl = p->rmargin;
+ vend += p->rmargin - p->offset;
+ } else
+ vbl = p->offset;
+
+ /* Remove the p->overstep width. */
+
+ 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 (' ' == p->buf[i])
+ i++;
+ dv = (size_t)(i - j) * (*p->width)(p, ' ');
+ vbl += dv;
+ vend += dv;
+ break;
+ }
+ if (ASCII_NBRSP == p->buf[i]) {
+ vbl += (*p->width)(p, ' ');
+ 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;
+ }
+
+ if (ASCII_HYPH == p->buf[i]) {
+ (*p->letter)(p, '-');
+ p->viscol += (*p->width)(p, '-');
+ continue;
+ }
+
+ (*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;
git.ckatri.com / mandoc.git / blobdiff