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 	TAILQ_INIT(&p->head);
44 }
45 
46 static int
47 tpatch_parse(struct parser *p, const char *buf, size_t size)
48 {
49 	return parser_foreach_line(p, buf, size, tpatch_foreach_line);
50 }
51 
52 static int
53 tpatch_emit_line(struct parser *p, const char *line, size_t linelen)
54 {
55 	struct line *l;
56 
57 	if ((l = calloc(1, sizeof(*l))) == NULL)
58 		return 0;
59 
60 	if (p->flags & PARSER_IN_PATCH_HDR)
61 		l->type = LINE_PATCH_HDR;
62 	else
63 		l->type = LINE_PATCH;
64 
65 	if (linelen != 0) {
66 		if ((l->line = calloc(1, linelen+1)) == NULL) {
67 			free(l);
68 			return 0;
69 		}
70 
71 		memcpy(l->line, line, linelen);
72 
73 		if (!(p->flags & PARSER_IN_PATCH_HDR))
74 			switch (*l->line) {
75 			case '+':
76 				l->type = LINE_PATCH_ADD;
77 				break;
78 			case '-':
79 				l->type = LINE_PATCH_DEL;
80 				break;
81 			case '@':
82 				l->type = LINE_PATCH_HUNK_HDR;
83 				break;
84 			}
85 
86 		if (has_prefix(l->line, "+++"))
87 			p->flags &= ~PARSER_IN_PATCH_HDR;
88 	}
89 
90 	TAILQ_INSERT_TAIL(&p->head, l, lines);
91 
92 	return 1;
93 }
94 
95 static int
96 tpatch_foreach_line(struct parser *p, const char *line, size_t linelen)
97 {
98 	return tpatch_emit_line(p, line, linelen);
99 }
100 
101 static int
102 tpatch_free(struct parser *p)
103 {
104 	if (p->len != 0)
105 		return tpatch_emit_line(p, p->buf, p->len);
106 	return 1;
107 }