xref: /freebsd/contrib/mandoc/eqn_term.c (revision 43d1e6ee299ad4e143d90d3ad374d1c24bd3306f)
1 /*	$Id: eqn_term.c,v 1.19 2018/12/13 05:23:38 schwarze Exp $ */
2 /*
3  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2014, 2015, 2017 Ingo Schwarze <schwarze@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 #include "config.h"
19 
20 #include <sys/types.h>
21 
22 #include <assert.h>
23 #include <ctype.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 
28 #include "eqn.h"
29 #include "out.h"
30 #include "term.h"
31 
32 static	const enum termfont fontmap[EQNFONT__MAX] = {
33 	TERMFONT_NONE, /* EQNFONT_NONE */
34 	TERMFONT_NONE, /* EQNFONT_ROMAN */
35 	TERMFONT_BOLD, /* EQNFONT_BOLD */
36 	TERMFONT_BOLD, /* EQNFONT_FAT */
37 	TERMFONT_UNDER /* EQNFONT_ITALIC */
38 };
39 
40 static void	eqn_box(struct termp *, const struct eqn_box *);
41 
42 
43 void
44 term_eqn(struct termp *p, const struct eqn_box *bp)
45 {
46 
47 	eqn_box(p, bp);
48 	p->flags &= ~TERMP_NOSPACE;
49 }
50 
51 static void
52 eqn_box(struct termp *p, const struct eqn_box *bp)
53 {
54 	const struct eqn_box *child;
55 	const char *cp;
56 	int delim;
57 
58 	/* Delimiters around this box? */
59 
60 	if ((bp->type == EQN_LIST && bp->expectargs > 1) ||
61 	    (bp->type == EQN_PILE && (bp->prev || bp->next)) ||
62 	    (bp->parent != NULL && (bp->parent->pos == EQNPOS_SQRT ||
63 	    /* Diacritic followed by ^ or _. */
64 	    ((bp->top != NULL || bp->bottom != NULL) &&
65 	     bp->parent->type == EQN_SUBEXPR &&
66 	     bp->parent->pos != EQNPOS_OVER && bp->next != NULL) ||
67 	    /* Nested over, sub, sup, from, to. */
68 	    (bp->type == EQN_SUBEXPR && bp->pos != EQNPOS_SQRT &&
69 	     ((bp->parent->type == EQN_LIST && bp->expectargs == 1) ||
70 	      (bp->parent->type == EQN_SUBEXPR &&
71 	       bp->pos != EQNPOS_SQRT)))))) {
72 		if ((bp->parent->type == EQN_SUBEXPR && bp->prev != NULL) ||
73 		    (bp->type == EQN_LIST &&
74 		     bp->first != NULL &&
75 		     bp->first->type != EQN_PILE &&
76 		     bp->first->type != EQN_MATRIX &&
77 		     bp->prev != NULL &&
78 		     (bp->prev->type == EQN_LIST ||
79 		      (bp->prev->type == EQN_TEXT &&
80 		       (*bp->prev->text == '\\' ||
81 		        isalpha((unsigned char)*bp->prev->text))))))
82 			p->flags |= TERMP_NOSPACE;
83 		term_word(p, bp->left != NULL ? bp->left : "(");
84 		p->flags |= TERMP_NOSPACE;
85 		delim = 1;
86 	} else
87 		delim = 0;
88 
89 	/* Handle Fonts and text. */
90 
91 	if (bp->font != EQNFONT_NONE)
92 		term_fontpush(p, fontmap[(int)bp->font]);
93 
94 	if (bp->text != NULL) {
95 		if (strchr("!\"'),.:;?]}", *bp->text) != NULL)
96 			p->flags |= TERMP_NOSPACE;
97 		term_word(p, bp->text);
98 		if ((cp = strchr(bp->text, '\0')) > bp->text &&
99 		    (strchr("\"'([{", cp[-1]) != NULL ||
100 		     (bp->prev == NULL && (cp[-1] == '-' ||
101 		      (cp >= bp->text + 5 &&
102 		       strcmp(cp - 5, "\\[mi]") == 0)))))
103 			p->flags |= TERMP_NOSPACE;
104 	}
105 
106 	/* Special box types. */
107 
108 	if (bp->pos == EQNPOS_SQRT) {
109 		term_word(p, "\\(sr");
110 		if (bp->first != NULL) {
111 			p->flags |= TERMP_NOSPACE;
112 			eqn_box(p, bp->first);
113 		}
114 	} else if (bp->type == EQN_SUBEXPR) {
115 		child = bp->first;
116 		eqn_box(p, child);
117 		p->flags |= TERMP_NOSPACE;
118 		term_word(p, bp->pos == EQNPOS_OVER ? "/" :
119 		    (bp->pos == EQNPOS_SUP ||
120 		     bp->pos == EQNPOS_TO) ? "^" : "_");
121 		child = child->next;
122 		if (child != NULL) {
123 			p->flags |= TERMP_NOSPACE;
124 			eqn_box(p, child);
125 			if (bp->pos == EQNPOS_FROMTO ||
126 			    bp->pos == EQNPOS_SUBSUP) {
127 				p->flags |= TERMP_NOSPACE;
128 				term_word(p, "^");
129 				p->flags |= TERMP_NOSPACE;
130 				child = child->next;
131 				if (child != NULL)
132 					eqn_box(p, child);
133 			}
134 		}
135 	} else {
136 		child = bp->first;
137 		if (bp->type == EQN_MATRIX &&
138 		    child != NULL &&
139 		    child->type == EQN_LIST &&
140 		    child->expectargs > 1)
141 			child = child->first;
142 		while (child != NULL) {
143 			eqn_box(p,
144 			    bp->type == EQN_PILE &&
145 			    child->type == EQN_LIST &&
146 			    child->expectargs > 1 &&
147 			    child->args == 1 ?
148 			    child->first : child);
149 			child = child->next;
150 		}
151 	}
152 
153 	/* Handle Fonts and diacritics. */
154 
155 	if (bp->font != EQNFONT_NONE)
156 		term_fontpop(p);
157 	if (bp->top != NULL) {
158 		p->flags |= TERMP_NOSPACE;
159 		term_word(p, bp->top);
160 	}
161 	if (bp->bottom != NULL) {
162 		p->flags |= TERMP_NOSPACE;
163 		term_word(p, "_");
164 	}
165 
166 	/* Right delimiter after this box? */
167 
168 	if (delim) {
169 		p->flags |= TERMP_NOSPACE;
170 		term_word(p, bp->right != NULL ? bp->right : ")");
171 		if (bp->parent->type == EQN_SUBEXPR && bp->next != NULL)
172 			p->flags |= TERMP_NOSPACE;
173 	}
174 }
175