xref: /openbsd-src/usr.bin/mandoc/eqn_html.c (revision 6a13ef69787db04ae501a22e92fa10865b44fd7c)
1 /*	$OpenBSD: eqn_html.c,v 1.7 2017/01/17 01:47:46 schwarze Exp $ */
2 /*
3  * Copyright (c) 2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 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 <sys/types.h>
19 
20 #include <assert.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 
25 #include "mandoc.h"
26 #include "out.h"
27 #include "html.h"
28 
29 static void
30 eqn_box(struct html *p, const struct eqn_box *bp)
31 {
32 	struct tag	*post, *row, *cell, *t;
33 	const struct eqn_box *child, *parent;
34 	size_t		 i, j, rows;
35 
36 	if (NULL == bp)
37 		return;
38 
39 	post = NULL;
40 
41 	/*
42 	 * Special handling for a matrix, which is presented to us in
43 	 * column order, but must be printed in row-order.
44 	 */
45 	if (EQN_MATRIX == bp->type) {
46 		if (NULL == bp->first)
47 			goto out;
48 		if (EQN_LIST != bp->first->type) {
49 			eqn_box(p, bp->first);
50 			goto out;
51 		}
52 		if (NULL == (parent = bp->first->first))
53 			goto out;
54 		/* Estimate the number of rows, first. */
55 		if (NULL == (child = parent->first))
56 			goto out;
57 		for (rows = 0; NULL != child; rows++)
58 			child = child->next;
59 		/* Print row-by-row. */
60 		post = print_otag(p, TAG_MTABLE, "");
61 		for (i = 0; i < rows; i++) {
62 			parent = bp->first->first;
63 			row = print_otag(p, TAG_MTR, "");
64 			while (NULL != parent) {
65 				child = parent->first;
66 				for (j = 0; j < i; j++) {
67 					if (NULL == child)
68 						break;
69 					child = child->next;
70 				}
71 				cell = print_otag(p, TAG_MTD, "");
72 				/*
73 				 * If we have no data for this
74 				 * particular cell, then print a
75 				 * placeholder and continue--don't puke.
76 				 */
77 				if (NULL != child)
78 					eqn_box(p, child->first);
79 				print_tagq(p, cell);
80 				parent = parent->next;
81 			}
82 			print_tagq(p, row);
83 		}
84 		goto out;
85 	}
86 
87 	switch (bp->pos) {
88 	case (EQNPOS_TO):
89 		post = print_otag(p, TAG_MOVER, "");
90 		break;
91 	case (EQNPOS_SUP):
92 		post = print_otag(p, TAG_MSUP, "");
93 		break;
94 	case (EQNPOS_FROM):
95 		post = print_otag(p, TAG_MUNDER, "");
96 		break;
97 	case (EQNPOS_SUB):
98 		post = print_otag(p, TAG_MSUB, "");
99 		break;
100 	case (EQNPOS_OVER):
101 		post = print_otag(p, TAG_MFRAC, "");
102 		break;
103 	case (EQNPOS_FROMTO):
104 		post = print_otag(p, TAG_MUNDEROVER, "");
105 		break;
106 	case (EQNPOS_SUBSUP):
107 		post = print_otag(p, TAG_MSUBSUP, "");
108 		break;
109 	case (EQNPOS_SQRT):
110 		post = print_otag(p, TAG_MSQRT, "");
111 		break;
112 	default:
113 		break;
114 	}
115 
116 	if (bp->top || bp->bottom) {
117 		assert(NULL == post);
118 		if (bp->top && NULL == bp->bottom)
119 			post = print_otag(p, TAG_MOVER, "");
120 		else if (bp->top && bp->bottom)
121 			post = print_otag(p, TAG_MUNDEROVER, "");
122 		else if (bp->bottom)
123 			post = print_otag(p, TAG_MUNDER, "");
124 	}
125 
126 	if (EQN_PILE == bp->type) {
127 		assert(NULL == post);
128 		if (bp->first != NULL && bp->first->type == EQN_LIST)
129 			post = print_otag(p, TAG_MTABLE, "");
130 	} else if (bp->type == EQN_LIST &&
131 	    bp->parent && bp->parent->type == EQN_PILE) {
132 		assert(NULL == post);
133 		post = print_otag(p, TAG_MTR, "");
134 		print_otag(p, TAG_MTD, "");
135 	}
136 
137 	if (NULL != bp->text) {
138 		assert(NULL == post);
139 		post = print_otag(p, TAG_MI, "");
140 		print_text(p, bp->text);
141 	} else if (NULL == post) {
142 		if (NULL != bp->left || NULL != bp->right)
143 			post = print_otag(p, TAG_MFENCED, "??",
144 			    "open", bp->left == NULL ? "" : bp->left,
145 			    "close", bp->right == NULL ? "" : bp->right);
146 		if (NULL == post)
147 			post = print_otag(p, TAG_MROW, "");
148 		else
149 			print_otag(p, TAG_MROW, "");
150 	}
151 
152 	eqn_box(p, bp->first);
153 
154 out:
155 	if (NULL != bp->bottom) {
156 		t = print_otag(p, TAG_MO, "");
157 		print_text(p, bp->bottom);
158 		print_tagq(p, t);
159 	}
160 	if (NULL != bp->top) {
161 		t = print_otag(p, TAG_MO, "");
162 		print_text(p, bp->top);
163 		print_tagq(p, t);
164 	}
165 
166 	if (NULL != post)
167 		print_tagq(p, post);
168 
169 	eqn_box(p, bp->next);
170 }
171 
172 void
173 print_eqn(struct html *p, const struct eqn *ep)
174 {
175 	struct tag	*t;
176 
177 	t = print_otag(p, TAG_MATH, "c", "eqn");
178 
179 	p->flags |= HTML_NONOSPACE;
180 	eqn_box(p, ep->root);
181 	p->flags &= ~HTML_NONOSPACE;
182 
183 	print_tagq(p, t);
184 }
185