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 <errno.h>
20 #include <limits.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25 
26 static void		 die(void) __attribute__((__noreturn__));
27 static void		 serve_bookmarks(uint32_t);
28 static void		 handle_get(struct imsg*, size_t);
29 static void		 handle_quit(struct imsg*, size_t);
30 static void		 dispatch_imsg(int, short, void*);
31 
32 static struct event		 imsgev;
33 static struct imsgbuf		*ibuf;
34 
35 static imsg_handlerfn *handlers[] = {
36 	[IMSG_GET] = handle_get,
37 	[IMSG_QUIT] = handle_quit,
38 };
39 
40 static void __attribute__((__noreturn__))
41 die(void)
42 {
43 	abort(); 		/* TODO */
44 }
45 
46 static void
47 serve_bookmarks(uint32_t peerid)
48 {
49 	const char	*t;
50 	char		 path[PATH_MAX], buf[BUFSIZ];
51 	size_t		 r;
52 	FILE		*f;
53 
54 	strlcpy(path, getenv("HOME"), sizeof(path));
55 	strlcat(path, "/.telescope/bookmarks.gmi", sizeof(path));
56 
57 	if ((f = fopen(path, "r")) == NULL) {
58 		t = "# error\n\nCan't open ~/.telescope/bookmarks.gmi";
59 		imsg_compose(ibuf, IMSG_BUF, peerid, 0, -1, t, strlen(t));
60 		imsg_compose(ibuf, IMSG_EOF, peerid, 0, -1, NULL, 0);
61 		imsg_flush(ibuf);
62 		return;
63 	}
64 
65 	for (;;) {
66 		r = fread(buf, 1, sizeof(buf), f);
67 		imsg_compose(ibuf, IMSG_BUF, peerid, 0, -1, buf, r);
68 		imsg_flush(ibuf);
69 		if (r != sizeof(buf))
70 			break;
71 	}
72 
73 	imsg_compose(ibuf, IMSG_EOF, peerid, 0, -1, NULL, 0);
74 	imsg_flush(ibuf);
75 
76 	fclose(f);
77 }
78 
79 static void
80 handle_get(struct imsg *imsg, size_t datalen)
81 {
82 	char		*data;
83 	const char	*p;
84 
85 	data = imsg->data;
86 
87 	if (data[datalen-1] != '\0')
88 		die();
89 
90 	if (!strcmp(data, "about:new")) {
91 		imsg_compose(ibuf, IMSG_BUF, imsg->hdr.peerid, 0, -1,
92 		    about_new, strlen(about_new));
93 		imsg_compose(ibuf, IMSG_EOF, imsg->hdr.peerid, 0, -1, NULL, 0);
94 		imsg_flush(ibuf);
95 	} else if (!strcmp(data, "about:bookmarks")) {
96 		serve_bookmarks(imsg->hdr.peerid);
97 	} else {
98 		p = "# not found!\n";
99 		imsg_compose(ibuf, IMSG_BUF, imsg->hdr.peerid, 0, -1, p, strlen(p));
100 		imsg_compose(ibuf, IMSG_EOF, imsg->hdr.peerid, 0, -1, NULL, 0);
101 		imsg_flush(ibuf);
102 	}
103 }
104 
105 static void
106 handle_quit(struct imsg *imsg, size_t datalen)
107 {
108 	event_loopbreak();
109 }
110 
111 static void
112 dispatch_imsg(int fd, short ev, void *d)
113 {
114 	struct imsgbuf	*ibuf = d;
115 	struct imsg	 imsg;
116 	ssize_t		 n;
117 	size_t		 datalen;
118 
119 	if ((n = imsg_read(ibuf)) == -1) {
120 		if (errno == EAGAIN || errno == EWOULDBLOCK)
121 			return;
122 		_exit(1);
123 	}
124 
125 	if (n == 0)
126 		_exit(1);
127 
128 	for (;;) {
129 		if ((n = imsg_get(ibuf, &imsg)) == -1)
130 			_exit(1);
131 		if (n == 0)
132 			return;
133 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
134 		handlers[imsg.hdr.type](&imsg, datalen);
135 		imsg_free(&imsg);
136 	}
137 }
138 
139 int
140 fs_main(struct imsgbuf *b)
141 {
142 	ibuf = b;
143 
144 	event_init();
145 
146 	event_set(&imsgev, ibuf->fd, EV_READ | EV_PERSIST, dispatch_imsg, ibuf);
147 	event_add(&imsgev, NULL);
148 
149 	sandbox_fs_process();
150 
151 	event_dispatch();
152 	return 0;
153 }