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 <errno.h>
18 #include <stdlib.h>
19 #include <string.h>
20 
21 #include "gmid.h"
22 
23 struct etm {			/* extension to mime */
24 	const char	*mime;
25 	const char	*ext;
26 };
27 
28 struct mimes {
29 	char		*def;
30 	struct etm	*t;
31 	size_t		len;
32 	size_t		cap;
33 };
34 
35 struct mimes mimes;
36 
37 void
38 init_mime(void)
39 {
40 	mimes.len = 0;
41 	mimes.cap = 2;
42 
43 	if ((mimes.t = calloc(mimes.cap, sizeof(struct etm))) == NULL)
44 		fatal("calloc: %s", strerror(errno));
45 
46 	mimes.def = strdup("application/octet-stream");
47 	if (mimes.def == NULL)
48 		fatal("strdup: %s", strerror(errno));
49 
50 }
51 
52 void
53 set_default_mime(const char *m)
54 {
55 	free(mimes.def);
56 	if ((mimes.def = strdup(m)) == NULL)
57 		fatal("strdup: %s", strerror(errno));
58 }
59 
60 /* register mime for the given extension */
61 void
62 add_mime(const char *mime, const char *ext)
63 {
64 	if (mimes.len == mimes.cap) {
65 		mimes.cap *= 1.5;
66 		mimes.t = realloc(mimes.t, mimes.cap * sizeof(struct etm));
67 		if (mimes.t == NULL)
68 			fatal("realloc: %s", strerror(errno));
69 	}
70 
71 	mimes.t[mimes.len].mime = mime;
72 	mimes.t[mimes.len].ext  = ext;
73 	mimes.len++;
74 }
75 
76 /* load a default set of common mime-extension associations */
77 void
78 load_default_mime()
79 {
80 	struct etm *i, m[] = {
81 		{"application/pdf",	"pdf"},
82 		{"image/gif",		"gif"},
83 		{"image/jpeg",		"jpg"},
84 		{"image/jpeg",		"jpeg"},
85 		{"image/png",		"png"},
86 		{"image/svg+xml",	"svg"},
87 		{"text/gemini",		"gemini"},
88 		{"text/gemini",		"gmi"},
89 		{"text/markdown",	"markdown"},
90 		{"text/markdown",	"md"},
91 		{"text/plain",		"txt"},
92 		{"text/xml",		"xml"},
93 		{NULL, NULL}
94 	};
95 
96 	for (i = m; i->mime != NULL; ++i)
97 		add_mime(i->mime, i->ext);
98 }
99 
100 static const char *
101 path_ext(const char *path)
102 {
103 	const char *end;
104 
105 	end = path + strlen(path)-1;
106 	for (; end != path; --end) {
107 		if (*end == '.')
108 			return end+1;
109 		if (*end == '/')
110 			break;
111 	}
112 
113 	return NULL;
114 }
115 
116 const char *
117 mime(const char *path)
118 {
119 	const char *ext;
120 	struct etm *t;
121 
122 	if ((ext = path_ext(path)) == NULL)
123 		return mimes.def;
124 
125 	for (t = mimes.t; t->mime != NULL; ++t)
126 		if (!strcmp(ext, t->ext))
127 			return t->mime;
128 
129 	return mimes.def;
130 }