1 /*
2  * Copyright (c) 2021 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 "telescope.h"
18 
19 #include <stdlib.h>
20 #include <string.h>
21 
22 int
23 parser_append(struct parser *p, const char *buf, size_t len)
24 {
25 	size_t newlen;
26 	char *t;
27 
28 	newlen = len + p->len;
29 	if ((t = calloc(1, newlen)) == NULL)
30 		return 0;
31 	memcpy(t, p->buf, p->len);
32 	memcpy(t + p->len, buf, len);
33 	free(p->buf);
34 	p->buf = t;
35 	p->len = newlen;
36 	return 1;
37 }
38 
39 int
40 parser_set_buf(struct parser *p, const char *buf, size_t len)
41 {
42 	char *tmp;
43 
44 	if (len == 0) {
45 		p->len = 0;
46 		free(p->buf);
47 		p->buf = NULL;
48 		return 1;
49 	}
50 
51 	/* p->buf and buf can (and probably almost always will)
52 	 * overlap! */
53 
54 	if ((tmp = calloc(1, len)) == NULL)
55 		return 0;
56 	memcpy(tmp, buf, len);
57 	free(p->buf);
58 	p->buf = tmp;
59 	p->len = len;
60 	return 1;
61 }
62 
63 int
64 parser_foreach_line(struct parser *p, const char *buf, size_t size,
65     parsechunkfn fn)
66 {
67 	char		*b, *e;
68 	unsigned int	 ch;
69 	size_t		 i, l, len;
70 
71 	if (!parser_append(p, buf, size))
72 		return 0;
73 	b = p->buf;
74 	len = p->len;
75 
76 	/* drop every "funny" ASCII character */
77 	for (i = 0; i < len; ) {
78 		ch = b[i];
79 		if ((ch >= ' ' || ch == '\n' || ch == '\t')
80 		    && ch != 127) { /* del */
81 			++i;
82 			continue;
83 		}
84 		memmove(&b[i], &b[i+1], len - i);
85 		len--;
86 	}
87 
88 	while (len > 0) {
89 		if ((e = memmem((char*)b, len, "\n", 1)) == NULL)
90 			break;
91 		l = e - b;
92 
93 		if (!fn(p, b, l))
94 			return 0;
95 
96 		len -= l;
97 		b += l;
98 
99 		if (len > 0) {
100 			/* skip \n */
101 			len--;
102 			b++;
103 		}
104 	}
105 
106 	return parser_set_buf(p, b, len);
107 }