1 /*
2  * Copyright (c) 2022 Omar Polo <op@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <ctype.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 
21 #include "tmpl.h"
22 
23 int
24 tp_urlescape(struct template *tp, const char *str)
25 {
26 	int	 r;
27 	char	 tmp[4];
28 
29 	if (str == NULL)
30 		return (0);
31 
32 	for (; *str; ++str) {
33 		if (iscntrl((unsigned char)*str) ||
34 		    isspace((unsigned char)*str) ||
35 		    *str == '\'' || *str == '"' || *str == '\\') {
36 			r = snprintf(tmp, sizeof(tmp), "%%%2X", *str);
37 			if (r < 0  || (size_t)r >= sizeof(tmp))
38 				return (0);
39 			if (tp->tp_puts(tp, tmp) == -1)
40 				return (-1);
41 		} else {
42 			if (tp->tp_putc(tp, *str) == -1)
43 				return (-1);
44 		}
45 	}
46 
47 	return (0);
48 }
49 
50 int
51 tp_htmlescape(struct template *tp, const char *str)
52 {
53 	int r;
54 
55 	if (str == NULL)
56 		return (0);
57 
58 	for (; *str; ++str) {
59 		switch (*str) {
60 		case '<':
61 			r = tp->tp_puts(tp, "&lt;");
62 			break;
63 		case '>':
64 			r = tp->tp_puts(tp, "&gt;");
65 			break;
66 		case '&':
67 			r = tp->tp_puts(tp, "&amp;");
68 			break;
69 		case '"':
70 			r = tp->tp_puts(tp, "&quot;");
71 			break;
72 		case '\'':
73 			r = tp->tp_puts(tp, "&apos;");
74 			break;
75 		default:
76 			r = tp->tp_putc(tp, *str);
77 			break;
78 		}
79 
80 		if (r == -1)
81 			return (-1);
82 	}
83 
84 	return (0);
85 }
86 
87 struct template *
88 template(void *arg, tmpl_puts putsfn, tmpl_putc putcfn)
89 {
90 	struct template *tp;
91 
92 	if ((tp = calloc(1, sizeof(*tp))) == NULL)
93 		return (NULL);
94 
95 	tp->tp_arg = arg;
96 	tp->tp_escape = tp_htmlescape;
97 	tp->tp_puts = putsfn;
98 	tp->tp_putc = putcfn;
99 
100 	return (tp);
101 }
102 
103 void
104 template_free(struct template *tp)
105 {
106 	free(tp->tp_tmp);
107 	free(tp);
108 }