+/* If str points to a valid hostspec, return allocated memory containing the
+ * [USER@]HOST part of the string, and set the path_start_ptr to the part of
+ * the string after the host part. Otherwise, return NULL. If port_ptr is
+ * non-NULL, we must be parsing an rsync:// URL hostname, and we will set
+ * *port_ptr if a port number is found. Note that IPv6 IPs will have their
+ * (required for parsing) [ and ] chars elided from the returned string. */
+static char *parse_hostspec(char *str, char **path_start_ptr, int *port_ptr)
+{
+ char *s, *host_start = str;
+ int hostlen = 0, userlen = 0;
+ char *ret;
+
+ for (s = str; ; s++) {
+ if (!*s) {
+ /* It is only OK if we run out of string with rsync:// */
+ if (!port_ptr)
+ return NULL;
+ if (!hostlen)
+ hostlen = s - host_start;
+ break;
+ }
+ if (*s == ':' || *s == '/') {
+ if (!hostlen)
+ hostlen = s - host_start;
+ if (*s++ == '/') {
+ if (!port_ptr)
+ return NULL;
+ } else if (port_ptr) {
+ *port_ptr = atoi(s);
+ while (isDigit(s)) s++;
+ if (*s && *s++ != '/')
+ return NULL;
+ }
+ break;
+ }
+ if (*s == '@') {
+ userlen = s - str + 1;
+ host_start = s + 1;
+ } else if (*s == '[') {
+ if (s != host_start++)
+ return NULL;
+ while (*s && *s != ']' && *s != '/') s++; /*SHARED ITERATOR*/
+ hostlen = s - host_start;
+ if (*s != ']' || (s[1] && s[1] != '/' && s[1] != ':') || !hostlen)
+ return NULL;
+ }
+ }
+
+ *path_start_ptr = s;
+ ret = new_array(char, userlen + hostlen + 1);
+ if (userlen)
+ strlcpy(ret, str, userlen + 1);
+ strlcpy(ret + userlen, host_start, hostlen + 1);
+ return ret;
+}
+