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 				tp->tp_ret = -1;
36 				return (-1);
37 			}
38 			if (tp->tp_puts(tp, tmp) == -1)
39 				return (-1);
40 		} else {
41 			if (tp->tp_putc(tp, *str) == -1)
42 				return (-1);
43 		}
44 	}
45 
46 	return (0);
47 }
48 
49 int
50 tp_htmlescape(struct template *tp, const char *str)
51 {
52 	int r;
53 
54 	for (; *str; ++str) {
55 		switch (*str) {
56 		case '<':
57 			r = tp->tp_puts(tp, "&lt;");
58 			break;
59 		case '>':
60 			r = tp->tp_puts(tp, "&gt;");
61 			break;
62 		case '&':
63 			r = tp->tp_puts(tp, "&amp;");
64 			break;
65 		case '"':
66 			r = tp->tp_puts(tp, "&quot;");
67 			break;
68 		case '\'':
69 			r = tp->tp_puts(tp, "&apos;");
70 			break;
71 		default:
72 			r = tp->tp_putc(tp, *str);
73 			break;
74 		}
75 
76 		if (r == -1) {
77 			tp->tp_ret = -1;
78 			return (-1);
79 		}
80 	}
81 
82 	return (0);
83 }
84 
85 struct template *
86 template(void *arg, tmpl_puts putsfn, tmpl_putc putcfn)
87 {
88 	struct template *tp;
89 
90 	if ((tp = calloc(1, sizeof(*tp))) == NULL)
91 		return (NULL);
92 
93 	tp->tp_arg = arg;
94 	tp->tp_escape = tp_htmlescape;
95 	tp->tp_puts = putsfn;
96 	tp->tp_putc = putcfn;
97 
98 	return (tp);
99 }
100 
101 void
102 template_reset(struct template *tp)
103 {
104 	tp->tp_ret = 0;
105 }