12 // ----------------------------------------------------------------------------
13 // URL encode / decode
14 // code from: http://www.geekhideout.com/urlcode.shtml
16 /* Converts a hex character to its integer value */
17 char from_hex(char ch) {
18 return (char)(isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10);
21 /* Converts an integer value to its hex character*/
22 char to_hex(char code) {
23 static char hex[] = "0123456789abcdef";
24 return hex[code & 15];
27 /* Returns a url-encoded version of str */
28 /* IMPORTANT: be sure to free() the returned string after use */
29 char *url_encode(char *str) {
32 pbuf = buf = malloc(strlen(str) * 3 + 1);
35 fatal("Cannot allocate memory.");
38 if (isalnum(*str) || *str == '-' || *str == '_' || *str == '.' || *str == '~')
45 *pbuf++ = '%', *pbuf++ = to_hex(*str >> 4), *pbuf++ = to_hex(*str & 15);
51 // FIX: I think this is prudent. URLs can be as long as 2 KiB or more.
52 // We allocated 3 times more space to accomodate %NN encoding of
53 // non ASCII chars. If URL has none of these kind of chars we will
54 // end up with a big unused buffer.
56 // Try to shrink the buffer...
57 if (!!(pbuf = (char *)realloc(buf, strlen(buf)+1)))
63 /* Returns a url-decoded version of str */
64 /* IMPORTANT: be sure to free() the returned string after use */
65 char *url_decode(char *str) {
67 *buf = malloc(strlen(str) + 1),
71 fatal("Cannot allocate memory.");
75 if (pstr[1] && pstr[2]) {
76 *pbuf++ = from_hex(pstr[1]) << 4 | from_hex(pstr[2]);
80 else if (*pstr == '+')