url.con commit Merge branch 'jc/maint-name-rev-all' into maint (c9de921)
   1#include "cache.h"
   2#include "url.h"
   3
   4int is_urlschemechar(int first_flag, int ch)
   5{
   6        /*
   7         * The set of valid URL schemes, as per STD66 (RFC3986) is
   8         * '[A-Za-z][A-Za-z0-9+.-]*'. But use sightly looser check
   9         * of '[A-Za-z0-9][A-Za-z0-9+.-]*' because earlier version
  10         * of check used '[A-Za-z0-9]+' so not to break any remote
  11         * helpers.
  12         */
  13        int alphanumeric, special;
  14        alphanumeric = ch > 0 && isalnum(ch);
  15        special = ch == '+' || ch == '-' || ch == '.';
  16        return alphanumeric || (!first_flag && special);
  17}
  18
  19int is_url(const char *url)
  20{
  21        const char *url2, *first_slash;
  22
  23        if (!url)
  24                return 0;
  25        url2 = url;
  26        first_slash = strchr(url, '/');
  27
  28        /* Input with no slash at all or slash first can't be URL. */
  29        if (!first_slash || first_slash == url)
  30                return 0;
  31        /* Character before must be : and next must be /. */
  32        if (first_slash[-1] != ':' || first_slash[1] != '/')
  33                return 0;
  34        /* There must be something before the :// */
  35        if (first_slash == url + 1)
  36                return 0;
  37        /*
  38         * Check all characters up to first slash - 1. Only alphanum
  39         * is allowed.
  40         */
  41        url2 = url;
  42        while (url2 < first_slash - 1) {
  43                if (!is_urlschemechar(url2 == url, (unsigned char)*url2))
  44                        return 0;
  45                url2++;
  46        }
  47
  48        /* Valid enough. */
  49        return 1;
  50}
  51
  52static int url_decode_char(const char *q)
  53{
  54        int i;
  55        unsigned char val = 0;
  56        for (i = 0; i < 2; i++) {
  57                unsigned char c = *q++;
  58                val <<= 4;
  59                if (c >= '0' && c <= '9')
  60                        val += c - '0';
  61                else if (c >= 'a' && c <= 'f')
  62                        val += c - 'a' + 10;
  63                else if (c >= 'A' && c <= 'F')
  64                        val += c - 'A' + 10;
  65                else
  66                        return -1;
  67        }
  68        return val;
  69}
  70
  71static char *url_decode_internal(const char **query, const char *stop_at,
  72                                 struct strbuf *out, int decode_plus)
  73{
  74        const char *q = *query;
  75
  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 (decode_plus && 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        struct strbuf out = STRBUF_INIT;
 108        const char *colon = strchr(url, ':');
 109
 110        /* Skip protocol part if present */
 111        if (colon && url < colon) {
 112                strbuf_add(&out, url, colon - url);
 113                url = colon;
 114        }
 115        return url_decode_internal(&url, NULL, &out, 0);
 116}
 117
 118char *url_decode_parameter_name(const char **query)
 119{
 120        struct strbuf out = STRBUF_INIT;
 121        return url_decode_internal(query, "&=", &out, 1);
 122}
 123
 124char *url_decode_parameter_value(const char **query)
 125{
 126        struct strbuf out = STRBUF_INIT;
 127        return url_decode_internal(query, "&", &out, 1);
 128}
 129
 130void end_url_with_slash(struct strbuf *buf, const char *url)
 131{
 132        strbuf_addstr(buf, url);
 133        if (buf->len && buf->buf[buf->len - 1] != '/')
 134                strbuf_addstr(buf, "/");
 135}
 136
 137void str_end_url_with_slash(const char *url, char **dest) {
 138        struct strbuf buf = STRBUF_INIT;
 139        end_url_with_slash(&buf, url);
 140        free(*dest);
 141        *dest = strbuf_detach(&buf, NULL);
 142}