decode file:// and ssh:// URLs
[git/git.git] / url.c
CommitLineData
638794cd
JK
1#include "cache.h"
2
3int is_urlschemechar(int first_flag, int ch)
4{
5 /*
6 * The set of valid URL schemes, as per STD66 (RFC3986) is
7 * '[A-Za-z][A-Za-z0-9+.-]*'. But use sightly looser check
8 * of '[A-Za-z0-9][A-Za-z0-9+.-]*' because earlier version
9 * of check used '[A-Za-z0-9]+' so not to break any remote
10 * helpers.
11 */
12 int alphanumeric, special;
13 alphanumeric = ch > 0 && isalnum(ch);
14 special = ch == '+' || ch == '-' || ch == '.';
15 return alphanumeric || (!first_flag && special);
16}
17
18int is_url(const char *url)
19{
20 const char *url2, *first_slash;
21
22 if (!url)
23 return 0;
24 url2 = url;
25 first_slash = strchr(url, '/');
26
27 /* Input with no slash at all or slash first can't be URL. */
28 if (!first_slash || first_slash == url)
29 return 0;
30 /* Character before must be : and next must be /. */
31 if (first_slash[-1] != ':' || first_slash[1] != '/')
32 return 0;
33 /* There must be something before the :// */
34 if (first_slash == url + 1)
35 return 0;
36 /*
37 * Check all characters up to first slash - 1. Only alphanum
38 * is allowed.
39 */
40 url2 = url;
41 while (url2 < first_slash - 1) {
42 if (!is_urlschemechar(url2 == url, (unsigned char)*url2))
43 return 0;
44 url2++;
45 }
46
47 /* Valid enough. */
48 return 1;
49}
50
51static int url_decode_char(const char *q)
52{
53 int i;
54 unsigned char val = 0;
55 for (i = 0; i < 2; i++) {
56 unsigned char c = *q++;
57 val <<= 4;
58 if (c >= '0' && c <= '9')
59 val += c - '0';
60 else if (c >= 'a' && c <= 'f')
61 val += c - 'a' + 10;
62 else if (c >= 'A' && c <= 'F')
63 val += c - 'A' + 10;
64 else
65 return -1;
66 }
67 return val;
68}
69
70static char *url_decode_internal(const char **query, const char *stop_at)
71{
72 const char *q = *query;
73 struct strbuf out;
74
75 strbuf_init(&out, 16);
76 do {
77 unsigned char c = *q;
78
79 if (!c)
80 break;
81 if (stop_at && strchr(stop_at, c)) {
82 q++;
83 break;
84 }
85
86 if (c == '%') {
87 int val = url_decode_char(q + 1);
88 if (0 <= val) {
89 strbuf_addch(&out, val);
90 q += 3;
91 continue;
92 }
93 }
94
95 if (c == '+')
96 strbuf_addch(&out, ' ');
97 else
98 strbuf_addch(&out, c);
99 q++;
100 } while (1);
101 *query = q;
102 return strbuf_detach(&out, NULL);
103}
104
105char *url_decode(const char *url)
106{
107 return url_decode_internal(&url, NULL);
108}
109
110char *url_decode_parameter_name(const char **query)
111{
112 return url_decode_internal(query, "&=");
113}
114
115char *url_decode_parameter_value(const char **query)
116{
117 return url_decode_internal(query, "&");
118}