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 #include "parser.h"
26 
27 const char *gemtext_prefixes[] = {
28 	[LINE_TEXT] = "",
29 	[LINE_TITLE_1] = "# ",
30 	[LINE_TITLE_2] = "## ",
31 	[LINE_TITLE_3] = "### ",
32 	[LINE_ITEM] = "* ",
33 	[LINE_QUOTE] = "> ",
34 	[LINE_PRE_START] = "``` ",
35 	[LINE_PRE_CONTENT] = "",
36 	[LINE_PRE_END] = "```",
37 };
38 
39 struct mcache {
40 	struct ohash	h;
41 	size_t		tot;
42 } mcache;
43 
44 struct mcache_entry {
45 	int		 trust;
46 	struct evbuffer	*evb;
47 	char		 url[];
48 };
49 
50 static void	*hash_alloc(size_t, void *);
51 static void	*hash_calloc(size_t, size_t, void *);
52 static void	 hash_free(void *, void *);
53 
54 static void *
55 hash_alloc(size_t len, void *d)
56 {
57 	if ((d = malloc(len)) == NULL)
58 		abort();
59 	return d;
60 }
61 
62 static void *
63 hash_calloc(size_t nmemb, size_t size, void *d)
64 {
65 	if ((d = calloc(nmemb, size)) == NULL)
66 		abort();
67 	return d;
68 }
69 
70 static void
71 hash_free(void *ptr, void *d)
72 {
73 	free(ptr);
74 }
75 
76 void
77 mcache_init(void)
78 {
79 	struct ohash_info info = {
80 		.key_offset = offsetof(struct mcache_entry, url),
81 		.calloc = hash_calloc,
82 		.free = hash_free,
83 		.alloc = hash_alloc,
84 	};
85 
86 	ohash_init(&mcache.h, 5, &info);
87 }
88 
89 int
90 mcache_tab(struct tab *tab)
91 {
92 	struct mcache_entry	*e;
93 	struct line		*line;
94 	unsigned int		 slot;
95 	size_t			 l, len;
96 	const char		*url;
97 
98 	url = tab->hist_cur->h;
99 	l = strlen(url);
100 	len = sizeof(*e) + l + 1;
101 
102 	if ((e = calloc(1, len)) == NULL)
103 		return -1;
104 	e->trust = tab->trust;
105 	memcpy(e->url, url, l);
106 
107 	if ((e->evb = evbuffer_new()) == NULL)
108 		goto err;
109 
110 	TAILQ_FOREACH(line, &tab->buffer.page.head, lines) {
111 		const char	*text, *alt;
112 		int		 r;
113 
114 		if ((text = line->line) == NULL)
115 			text = "";
116 
117 		if ((alt = line->alt) == NULL)
118 			alt = "";
119 
120 		switch (line->type) {
121 		case LINE_TEXT:
122 		case LINE_TITLE_1:
123 		case LINE_TITLE_2:
124 		case LINE_TITLE_3:
125 		case LINE_ITEM:
126 		case LINE_QUOTE:
127 		case LINE_PRE_START:
128 		case LINE_PRE_CONTENT:
129 		case LINE_PRE_END:
130 			r = evbuffer_add_printf(e->evb, "%s%s\n",
131 			    gemtext_prefixes[line->type], text);
132 			break;
133 
134 		case LINE_LINK:
135 			r = evbuffer_add_printf(e->evb, "=> %s %s\n",
136 			    alt, text);
137 			break;
138 
139 		case LINE_PATCH:
140 		case LINE_PATCH_HDR:
141 		case LINE_PATCH_HUNK_HDR:
142 		case LINE_PATCH_ADD:
143 		case LINE_PATCH_DEL:
144 			/* TODO */
145 			r = -1;
146 			break;
147 
148 		case LINE_COMPL:
149 		case LINE_COMPL_CURRENT:
150 		case LINE_HELP:
151 		case LINE_DOWNLOAD:
152 		case LINE_DOWNLOAD_DONE:
153 		case LINE_DOWNLOAD_INFO:
154 		case LINE_FRINGE:
155 			/* not reached */
156 			abort();
157 		}
158 
159 		if (r == -1)
160 			goto err;
161 	}
162 
163 	slot = ohash_qlookup(&mcache.h, url);
164 	ohash_insert(&mcache.h, slot, e);
165 	return 0;
166 
167 err:
168 	if (e->evb != NULL)
169 		evbuffer_free(e->evb);
170 	free(e);
171 	return -1;
172 }
173 
174 int
175 mcache_lookup(const char *url, struct tab *tab)
176 {
177 	struct mcache_entry	*e;
178 	unsigned int		 slot;
179 
180 	slot = ohash_qlookup(&mcache.h, url);
181 	if ((e = ohash_find(&mcache.h, slot)) == NULL)
182 		return 0;
183 
184 	parser_init(tab, gemtext_initparser);
185 	if (!parser_parse(tab, EVBUFFER_DATA(e->evb), EVBUFFER_LENGTH(e->evb)))
186 		goto err;
187 	if (!parser_free(tab))
188 		goto err;
189 
190 	tab->trust = e->trust;
191 	return 1;
192 
193 err:
194 	parser_free(tab);
195 	erase_buffer(&tab->buffer);
196 	return 0;
197 }