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 "compat.h"
18 
19 #include <stdlib.h>
20 #include <stdint.h>
21 #include <string.h>
22 
23 #include "telescope.h"
24 #include "mcache.h"
25 
26 const char *gemtext_prefixes[] = {
27 	[LINE_TEXT] = "",
28 	[LINE_TITLE_1] = "# ",
29 	[LINE_TITLE_2] = "## ",
30 	[LINE_TITLE_3] = "### ",
31 	[LINE_ITEM] = "* ",
32 	[LINE_QUOTE] = "> ",
33 	[LINE_PRE_START] = "``` ",
34 	[LINE_PRE_CONTENT] = "",
35 	[LINE_PRE_END] = "```",
36 };
37 
38 struct mcache {
39 	struct ohash	h;
40 	size_t		tot;
41 } mcache;
42 
43 struct mcache_entry {
44 	int		 trust;
45 	struct evbuffer	*evb;
46 	char		 url[];
47 };
48 
49 static void	*hash_alloc(size_t, void *);
50 static void	*hash_calloc(size_t, size_t, void *);
51 static void	 hash_free(void *, void *);
52 
53 static void *
54 hash_alloc(size_t len, void *d)
55 {
56 	if ((d = malloc(len)) == NULL)
57 		abort();
58 	return d;
59 }
60 
61 static void *
62 hash_calloc(size_t nmemb, size_t size, void *d)
63 {
64 	if ((d = calloc(nmemb, size)) == NULL)
65 		abort();
66 	return d;
67 }
68 
69 static void
70 hash_free(void *ptr, void *d)
71 {
72 	free(ptr);
73 }
74 
75 void
76 mcache_init(void)
77 {
78 	struct ohash_info info = {
79 		.key_offset = offsetof(struct mcache_entry, url),
80 		.calloc = hash_calloc,
81 		.free = hash_free,
82 		.alloc = hash_alloc,
83 	};
84 
85 	ohash_init(&mcache.h, 5, &info);
86 }
87 
88 int
89 mcache_buffer(const char *url, struct buffer *buf, int trust)
90 {
91 	struct mcache_entry	*e;
92 	struct line		*line;
93 	unsigned int		 slot;
94 	size_t			 l, len;
95 
96 	l = strlen(url);
97 	len = sizeof(*e) + l + 1;
98 
99 	if ((e = calloc(1, len)) == NULL)
100 		return -1;
101 	e->trust = trust;
102 	memcpy(e->url, url, l);
103 
104 	if ((e->evb = evbuffer_new()) == NULL)
105 		goto err;
106 
107 	TAILQ_FOREACH(line, &buf->page.head, lines) {
108 		const char	*text, *alt;
109 		int		 r;
110 
111 		if ((text = line->line) == NULL)
112 			text = "";
113 
114 		if ((alt = line->alt) == NULL)
115 			alt = "";
116 
117 		switch (line->type) {
118 		case LINE_TEXT:
119 		case LINE_TITLE_1:
120 		case LINE_TITLE_2:
121 		case LINE_TITLE_3:
122 		case LINE_ITEM:
123 		case LINE_QUOTE:
124 		case LINE_PRE_START:
125 		case LINE_PRE_CONTENT:
126 		case LINE_PRE_END:
127 			r = evbuffer_add_printf(e->evb, "%s%s\n",
128 			    gemtext_prefixes[line->type], text);
129 			break;
130 
131 		case LINE_LINK:
132 			r = evbuffer_add_printf(e->evb, "=> %s %s\n",
133 			    alt, text);
134 			break;
135 
136 		case LINE_PATCH:
137 		case LINE_PATCH_HDR:
138 		case LINE_PATCH_HUNK_HDR:
139 		case LINE_PATCH_ADD:
140 		case LINE_PATCH_DEL:
141 			/* TODO */
142 			r = -1;
143 			break;
144 
145 		case LINE_COMPL:
146 		case LINE_COMPL_CURRENT:
147 		case LINE_HELP:
148 		case LINE_DOWNLOAD:
149 		case LINE_DOWNLOAD_DONE:
150 		case LINE_DOWNLOAD_INFO:
151 		case LINE_FRINGE:
152 			/* not reached */
153 			abort();
154 		}
155 
156 		if (r == -1)
157 			goto err;
158 	}
159 
160 	slot = ohash_qlookup(&mcache.h, url);
161 	ohash_insert(&mcache.h, slot, e);
162 	return 0;
163 
164 err:
165 	if (e->evb != NULL)
166 		evbuffer_free(e->evb);
167 	free(e);
168 	return -1;
169 }
170 
171 int
172 mcache_lookup(const char *url, struct evbuffer **ret, int *trust)
173 {
174 	struct mcache_entry	*e;
175 	unsigned int		 slot;
176 
177 	slot = ohash_qlookup(&mcache.h, url);
178 	if ((e = ohash_find(&mcache.h, slot)) == NULL)
179 		return 0;
180 
181 	*ret = e->evb;
182 	*trust = e->trust;
183 	return 1;
184 }