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 	const char	*parser_name;
46 	int		 trust;
47 	struct evbuffer	*evb;
48 	char		 url[];
49 };
50 
51 static void	*hash_alloc(size_t, void *);
52 static void	*hash_calloc(size_t, size_t, void *);
53 static void	 hash_free(void *, void *);
54 
55 static void *
56 hash_alloc(size_t len, void *d)
57 {
58 	if ((d = malloc(len)) == NULL)
59 		abort();
60 	return d;
61 }
62 
63 static void *
64 hash_calloc(size_t nmemb, size_t size, void *d)
65 {
66 	if ((d = calloc(nmemb, size)) == NULL)
67 		abort();
68 	return d;
69 }
70 
71 static void
72 hash_free(void *ptr, void *d)
73 {
74 	free(ptr);
75 }
76 
77 void
78 mcache_init(void)
79 {
80 	struct ohash_info info = {
81 		.key_offset = offsetof(struct mcache_entry, url),
82 		.calloc = hash_calloc,
83 		.free = hash_free,
84 		.alloc = hash_alloc,
85 	};
86 
87 	ohash_init(&mcache.h, 5, &info);
88 }
89 
90 int
91 mcache_tab(struct tab *tab)
92 {
93 	struct mcache_entry	*e;
94 	struct line		*line;
95 	unsigned int		 slot;
96 	size_t			 l, len;
97 	const char		*url;
98 
99 	url = tab->hist_cur->h;
100 	l = strlen(url);
101 	len = sizeof(*e) + l + 1;
102 
103 	if ((e = calloc(1, len)) == NULL)
104 		return -1;
105 	e->parser_name = tab->buffer.page.name;
106 	e->trust = tab->trust;
107 	memcpy(e->url, url, l);
108 
109 	if ((e->evb = evbuffer_new()) == NULL)
110 		goto err;
111 
112 	TAILQ_FOREACH(line, &tab->buffer.page.head, lines) {
113 		const char	*text, *alt;
114 		int		 r;
115 
116 		if ((text = line->line) == NULL)
117 			text = "";
118 
119 		if ((alt = line->alt) == NULL)
120 			alt = "";
121 
122 		switch (line->type) {
123 		case LINE_TEXT:
124 		case LINE_TITLE_1:
125 		case LINE_TITLE_2:
126 		case LINE_TITLE_3:
127 		case LINE_ITEM:
128 		case LINE_QUOTE:
129 		case LINE_PRE_START:
130 		case LINE_PRE_CONTENT:
131 		case LINE_PRE_END:
132 			r = evbuffer_add_printf(e->evb, "%s%s\n",
133 			    gemtext_prefixes[line->type], text);
134 			break;
135 
136 		case LINE_LINK:
137 			r = evbuffer_add_printf(e->evb, "=> %s %s\n",
138 			    alt, text);
139 			break;
140 
141 		case LINE_PATCH:
142 		case LINE_PATCH_HDR:
143 		case LINE_PATCH_HUNK_HDR:
144 		case LINE_PATCH_ADD:
145 		case LINE_PATCH_DEL:
146 			/* TODO */
147 			r = -1;
148 			break;
149 
150 		case LINE_COMPL:
151 		case LINE_COMPL_CURRENT:
152 		case LINE_HELP:
153 		case LINE_DOWNLOAD:
154 		case LINE_DOWNLOAD_DONE:
155 		case LINE_DOWNLOAD_INFO:
156 		case LINE_FRINGE:
157 			/* not reached */
158 			abort();
159 		}
160 
161 		if (r == -1)
162 			goto err;
163 	}
164 
165 	slot = ohash_qlookup(&mcache.h, url);
166 	ohash_insert(&mcache.h, slot, e);
167 	return 0;
168 
169 err:
170 	if (e->evb != NULL)
171 		evbuffer_free(e->evb);
172 	free(e);
173 	return -1;
174 }
175 
176 int
177 mcache_lookup(const char *url, struct tab *tab)
178 {
179 	struct mcache_entry	*e;
180 	unsigned int		 slot;
181 
182 	slot = ohash_qlookup(&mcache.h, url);
183 	if ((e = ohash_find(&mcache.h, slot)) == NULL)
184 		return 0;
185 
186 	parser_init(tab, gemtext_initparser);
187 	if (!parser_parse(tab, EVBUFFER_DATA(e->evb), EVBUFFER_LENGTH(e->evb)))
188 		goto err;
189 	if (!parser_free(tab))
190 		goto err;
191 
192 	tab->buffer.page.name = e->parser_name;
193 	tab->trust = e->trust;
194 	return 1;
195 
196 err:
197 	parser_free(tab);
198 	erase_buffer(&tab->buffer);
199 	return 0;
200 }