1 /*
2  * Copyright (c) 2022 Omar Polo <op@omarpolo.com>
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 	for (; *str; ++str) {
30 		if (iscntrl((unsigned char)*str) ||
31 		    isspace((unsigned char)*str) ||
32 		    *str == '\'' || *str == '"' || *str == '\\') {
33 			r = snprintf(tmp, sizeof(tmp), "%%%2X", *str);
34 			if (r < 0  || (size_t)r >= sizeof(tmp))
35 				return (0);
36 			if (tp->tp_puts(tp, tmp) == -1)
37 				return (-1);
38 		} else {
39 			if (tp->tp_putc(tp, *str) == -1)
40 				return (-1);
41 		}
42 	}
43 
44 	return (0);
45 }
46 
47 int
48 tp_htmlescape(struct template *tp, const char *str)
49 {
50 	int r;
51 
52 	for (; *str; ++str) {
53 		switch (*str) {
54 		case '<':
55 			r = tp->tp_puts(tp, "&lt;");
56 			break;
57 		case '>':
58 			r = tp->tp_puts(tp, "&gt;");
59 			break;
60 		case '&':
61 			r = tp->tp_puts(tp, "&amp;");
62 			break;
63 		case '"':
64 			r = tp->tp_puts(tp, "&quot;");
65 			break;
66 		case '\'':
67 			r = tp->tp_puts(tp, "&apos;");
68 			break;
69 		default:
70 			r = tp->tp_putc(tp, *str);
71 			break;
72 		}
73 
74 		if (r == -1)
75 			return (-1);
76 	}
77 
78 	return (0);
79 }
80 
81 struct template *
82 template(void *arg, tmpl_puts putsfn, tmpl_putc putcfn)
83 {
84 	struct template *tp;
85 
86 	if ((tp = calloc(1, sizeof(*tp))) == NULL)
87 		return (NULL);
88 
89 	tp->tp_arg = arg;
90 	tp->tp_escape = tp_htmlescape;
91 	tp->tp_puts = putsfn;
92 	tp->tp_putc = putcfn;
93 
94 	return (tp);
95 }
96 
97 void
98 template_free(struct template *tp)
99 {
100 	free(tp->tp_tmp);
101 	free(tp);
102 }