ref: 0065e9a53fb42e3116a469d44610c3c39d48c834
parent: c55cd099d93cd4a34a48f61bfffdba6866ea263a
author: Ali Gholami Rudi <[email protected]>
date: Tue Apr 29 13:08:45 EDT 2014
fmt: filling whole paragraphs without hyphenating
--- a/fmt.c
+++ b/fmt.c
@@ -24,9 +24,9 @@
struct word {
char *s;
- int wid;
- int elsn, elsp;
- int gap;
+ int wid; /* word's width */
+ int elsn, elsp; /* els_neg and els_pos */
+ int gap; /* the space before this word */
};
struct line {
@@ -42,6 +42,9 @@
/* queued lines */
struct line lines[NLINES];
int l_head, l_tail;
+ /* for paragraph adjustment */
+ long best[NWORDS];
+ int best_pos[NWORDS];
/* current line */
int gap; /* space before the next word */
int nls; /* newlines before the next word */
@@ -58,6 +61,11 @@
n_ti = -1;
}
+static int fmt_confchanged(struct fmt *f)
+{
+ return f->ll != n_l || f->li != (n_ti >= 0 ? n_ti : n_i);
+}
+
/* move words inside an fmt struct */
static void fmt_movewords(struct fmt *a, int dst, int src, int len)
{
@@ -64,55 +72,16 @@
memmove(a->words + dst, a->words + src, len * sizeof(a->words[0]));
}
-static char *fmt_strdup(char *s)
+/* move words from the buffer to s */
+static int fmt_wordscopy(struct fmt *f, int beg, int end,
+ struct sbuf *s, int *els_neg, int *els_pos)
{
- int l = strlen(s);
- char *r = malloc(l + 1);
- memcpy(r, s, l + 1);
- return r;
-}
-
-/* copy word buffer wb in fmt->words[i] */
-static void fmt_insertword(struct fmt *f, int i, struct wb *wb, int gap)
-{
- struct word *w = &f->words[i];
- w->s = fmt_strdup(wb_buf(wb));
- w->wid = wb_wid(wb);
- w->elsn = wb->els_neg;
- w->elsp = wb->els_pos;
- w->gap = gap;
-}
-
-/* the total width of the first n words in f->words[] */
-static int fmt_wordslen(struct fmt *f, int n)
-{
- int i, w = 0;
- for (i = 0; i < n; i++)
- w += f->words[i].wid + f->words[i].gap;
- return w;
-}
-
-/* select as many words as can be fit in llen */
-static int fmt_linefit(struct fmt *f, int llen)
-{
- int i, w = 0;
- for (i = 0; i < f->nwords; i++) {
- w += f->words[i].wid + f->words[i].gap;
- if (w > llen)
- return i;
- }
- return i;
-}
-
-/* move n words from the buffer to s */
-static int fmt_move(struct fmt *f, int n, struct sbuf *s, int *els_neg, int *els_pos)
-{
struct word *wcur;
int w = 0;
int i;
*els_neg = 0;
*els_pos = 0;
- for (i = 0; i < n; i++) {
+ for (i = beg; i < end; i++) {
wcur = &f->words[i];
sbuf_printf(s, "%ch'%du'", c_ec, wcur->gap);
sbuf_append(s, wcur->s);
@@ -123,15 +92,37 @@
*els_pos = wcur->elsp;
free(wcur->s);
}
- if (!n)
- return 0;
- f->nwords -= n;
- fmt_movewords(f, 0, n, f->nwords);
- if (f->nwords) /* apply the new .l and .i */
- fmt_confupdate(f);
return w;
}
+/* the total width of the specified words in f->words[] */
+static int fmt_wordslen(struct fmt *f, int beg, int end)
+{
+ int i, w = 0;
+ for (i = beg; i < end; i++)
+ w += f->words[i].wid + f->words[i].gap;
+ return w;
+}
+
+static char *fmt_strdup(char *s)
+{
+ int l = strlen(s);
+ char *r = malloc(l + 1);
+ memcpy(r, s, l + 1);
+ return r;
+}
+
+/* copy word buffer wb in fmt->words[i] */
+static void fmt_insertword(struct fmt *f, int i, struct wb *wb, int gap)
+{
+ struct word *w = &f->words[i];
+ w->s = fmt_strdup(wb_buf(wb));
+ w->wid = wb_wid(wb);
+ w->elsn = wb->els_neg;
+ w->elsp = wb->els_pos;
+ w->gap = gap;
+}
+
/* try to hyphenate the n-th word */
static void fmt_hyph(struct fmt *f, int n, int w, int hyph)
{
@@ -163,49 +154,6 @@
return NLINES - f->l_tail + f->l_head;
}
-int fmt_fill(struct fmt *f, int all)
-{
- int llen, fmt_div, fmt_rem;
- int w = 0;
- int i, n;
- struct line *l;
- int hyph = n_hy;
- if (!FMT_FILL(f))
- return 0;
- while (f->nwords) {
- l = &f->lines[f->l_head];
- llen = FMT_LLEN(f);
- if ((f->l_head + 1) % NLINES == f->l_tail)
- return 1;
- l->li = f->li;
- l->ll = f->ll;
- n = fmt_linefit(f, llen);
- if (n == f->nwords && !all)
- break;
- if ((n_hy & HY_LAST) && ren_safelines() < 2 + fmt_nlines(f))
- hyph = 0; /* disable hyphenation for final lines */
- if (n < f->nwords)
- fmt_hyph(f, n, llen - fmt_wordslen(f, n) -
- f->words[n].gap, hyph);
- n = fmt_linefit(f, llen);
- if (!n && f->nwords)
- n = 1;
- w = fmt_wordslen(f, n);
- if (FMT_ADJ(f) && n > 1) {
- fmt_div = (llen - w) / (n - 1);
- fmt_rem = (llen - w) % (n - 1);
- for (i = 0; i < n - 1; i++)
- f->words[i + 1].gap += fmt_div + (i < fmt_rem);
- }
- sbuf_init(&l->sbuf);
- l->wid = fmt_move(f, n, &l->sbuf, &l->elsn, &l->elsp);
- f->words[0].gap = 0;
- f->filled = n && !f->nwords;
- f->l_head = (f->l_head + 1) % NLINES;
- }
- return 0;
-}
-
/* return the next line in the buffer */
int fmt_nextline(struct fmt *f, struct sbuf *sbuf, int *w,
int *li, int *ll, int *els_neg, int *els_pos)
@@ -225,20 +173,29 @@
return 0;
}
+static struct line *fmt_mkline(struct fmt *f)
+{
+ struct line *l = &f->lines[f->l_head];
+ if ((f->l_head + 1) % NLINES == f->l_tail)
+ return NULL;
+ f->l_head = (f->l_head + 1) % NLINES;
+ l->li = f->li;
+ l->ll = f->ll;
+ sbuf_init(&l->sbuf);
+ return l;
+}
+
static int fmt_sp(struct fmt *f)
{
struct line *l;
fmt_fill(f, 0);
- if ((f->l_head + 1) % NLINES == f->l_tail)
+ l = fmt_mkline(f);
+ if (!l)
return 1;
- l = &f->lines[f->l_head];
f->filled = 0;
f->nls--;
- l->li = f->li;
- l->ll = f->ll;
- sbuf_init(&l->sbuf);
- l->wid = fmt_move(f, f->nwords, &l->sbuf, &l->elsn, &l->elsp);
- f->l_head = (f->l_head + 1) % NLINES;
+ l->wid = fmt_wordscopy(f, 0, f->nwords, &l->sbuf, &l->elsn, &l->elsp);
+ f->nwords = 0;
return 0;
}
@@ -275,7 +232,7 @@
/* insert wb into fmt */
void fmt_word(struct fmt *f, struct wb *wb)
{
- if (f->nwords == NWORDS)
+ if (f->nwords == NWORDS || fmt_confchanged(f))
fmt_fill(f, 0);
if (wb_empty(wb) || f->nwords == NWORDS)
return;
@@ -292,6 +249,123 @@
f->eos = wb_eos(wb);
}
+/* the cost of putting a line break before word pos */
+static long fmt_findcost(struct fmt *f, int pos)
+{
+ int i, w;
+ long cur;
+ int llen = FMT_LLEN(f);
+ if (pos <= 0)
+ return 0;
+ if (f->best_pos[pos] >= 0)
+ return f->best[pos];
+ i = pos - 1;
+ w = 0;
+ while (i >= 0) {
+ w += f->words[i].wid;
+ if (i + 1 < pos)
+ w += f->words[i + 1].gap;
+ if (w > llen && pos - i > 1)
+ break;
+ cur = fmt_findcost(f, i) + (llen - w) * (llen - w);
+ if (f->best_pos[pos] < 0 || cur < f->best[pos]) {
+ f->best_pos[pos] = i;
+ f->best[pos] = cur;
+ }
+ i--;
+ }
+ return f->best[pos];
+}
+
+/* the best position for breaking the line ending at pos */
+static int fmt_bestpos(struct fmt *f, int pos)
+{
+ fmt_findcost(f, pos);
+ return MAX(0, f->best_pos[pos]);
+}
+
+/* return the last filled word */
+static int fmt_breakparagraph(struct fmt *f, int pos, int all)
+{
+ int i, w;
+ long cur, best = 0;
+ int best_i = -1;
+ int llen = FMT_LLEN(f);
+ if (all || (pos > 0 && f->words[pos - 1].wid >= llen)) {
+ fmt_findcost(f, pos);
+ return pos;
+ }
+ i = pos - 1;
+ w = 0;
+ while (i >= 0) {
+ w += f->words[i].wid;
+ if (i + 1 < pos)
+ w += f->words[i + 1].gap;
+ if (w > llen && pos - i > 1)
+ break;
+ cur = fmt_findcost(f, i);
+ if (best_i < 0 || cur < best) {
+ best_i = i;
+ best = cur;
+ }
+ i--;
+ }
+ return best_i;
+}
+
+/* break f->words[0..end] into lines according to fmt_bestpos() */
+static int fmt_break(struct fmt *f, int end)
+{
+ int llen, fmt_div, fmt_rem, beg;
+ int n, w, i;
+ struct line *l;
+ int ret = 0;
+ beg = fmt_bestpos(f, end);
+ if (beg > 0)
+ ret += fmt_break(f, beg);
+ l = fmt_mkline(f);
+ if (!l)
+ return ret;
+ llen = FMT_LLEN(f);
+ f->words[beg].gap = 0;
+ w = fmt_wordslen(f, beg, end);
+ n = end - beg;
+ if (FMT_ADJ(f) && n > 1) {
+ fmt_div = (llen - w) / (n - 1);
+ fmt_rem = (llen - w) % (n - 1);
+ for (i = beg + 1; i < end; i++)
+ f->words[i].gap += fmt_div + (i < fmt_rem);
+ }
+ l->wid = fmt_wordscopy(f, beg, end, &l->sbuf, &l->elsn, &l->elsp);
+ if (beg > 0)
+ fmt_confupdate(f);
+ return ret + n;
+}
+
+int fmt_fill(struct fmt *f, int all)
+{
+ int end, n, i;
+ if (!FMT_FILL(f))
+ return 0;
+ /* not enough words to fill */
+ if (!all && fmt_wordslen(f, 0, f->nwords) <= FMT_LLEN(f))
+ return 0;
+ /* resetting positions */
+ for (i = 0; i < f->nwords + 1; i++)
+ f->best_pos[i] = -1;
+ end = fmt_breakparagraph(f, f->nwords, all);
+ /* recursively add lines */
+ n = fmt_break(f, end);
+ f->nwords -= n;
+ fmt_movewords(f, 0, n, f->nwords);
+ f->filled = n && !f->nwords;
+ if (f->nwords)
+ f->words[0].gap = 0;
+ if (f->nwords) /* apply the new .l and .i */
+ fmt_confupdate(f);
+ return n != end;
+}
+
struct fmt *fmt_alloc(void)
{
struct fmt *fmt = malloc(sizeof(*fmt));
@@ -306,7 +380,7 @@
int fmt_wid(struct fmt *fmt)
{
- return fmt_wordslen(fmt, fmt->nwords) +
+ return fmt_wordslen(fmt, 0, fmt->nwords) +
(fmt->nls ? FMT_SWID(fmt) : fmt->gap);
}