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 /*
18  * A streaming text/x-patch parser
19  */
20 
21 #include <stdlib.h>
22 #include <string.h>
23 
24 #include "telescope.h"
25 #include "parser.h"
26 
27 static int	tpatch_parse(struct parser *, const char *, size_t);
28 static int	tpatch_emit_line(struct parser *, const char *, size_t);
29 static int	tpatch_foreach_line(struct parser *, const char *, size_t);
30 static int	tpatch_free(struct parser *);
31 
32 void
33 textpatch_initparser(struct parser *p)
34 {
35 	memset(p, 0, sizeof(*p));
36 
37 	p->name = "text/x-patch";
38 	p->parse = &tpatch_parse;
39 	p->free = &tpatch_free;
40 
41 	p->flags = PARSER_IN_PATCH_HDR;
42 }
43 
44 static int
45 tpatch_parse(struct parser *p, const char *buf, size_t size)
46 {
47 	return parser_foreach_line(p, buf, size, tpatch_foreach_line);
48 }
49 
50 static int
51 tpatch_emit_line(struct parser *p, const char *line, size_t linelen)
52 {
53 	struct line *l;
54 
55 	if ((l = calloc(1, sizeof(*l))) == NULL)
56 		return 0;
57 
58 	if (p->flags & PARSER_IN_PATCH_HDR)
59 		l->type = LINE_PATCH_HDR;
60 	else
61 		l->type = LINE_PATCH;
62 
63 	if (linelen != 0) {
64 		if ((l->line = calloc(1, linelen+1)) == NULL) {
65 			free(l);
66 			return 0;
67 		}
68 
69 		memcpy(l->line, line, linelen);
70 
71 		if (!(p->flags & PARSER_IN_PATCH_HDR))
72 			switch (*l->line) {
73 			case '+':
74 				l->type = LINE_PATCH_ADD;
75 				break;
76 			case '-':
77 				l->type = LINE_PATCH_DEL;
78 				break;
79 			case '@':
80 				l->type = LINE_PATCH_HUNK_HDR;
81 				break;
82 			}
83 
84 		if (has_prefix(l->line, "+++"))
85 			p->flags &= ~PARSER_IN_PATCH_HDR;
86 	}
87 
88 	if (TAILQ_EMPTY(&p->head))
89 		TAILQ_INSERT_HEAD(&p->head, l, lines);
90 	else
91 		TAILQ_INSERT_TAIL(&p->head, l, lines);
92 
93 	return 1;
94 }
95 
96 static int
97 tpatch_foreach_line(struct parser *p, const char *line, size_t linelen)
98 {
99 	return tpatch_emit_line(p, line, linelen);
100 }
101 
102 static int
103 tpatch_free(struct parser *p)
104 {
105 	if (p->len != 0)
106 		return tpatch_emit_line(p, p->buf, p->len);
107 	return 1;
108 }