private static string GetPath(string uriString)
{
Debug.Assert(uriString != null, "uriString must not be null");
Debug.Assert(uriString.Length > 0, "uriString must not be empty");
int pathStartIndex = 0;
// Perf. improvement: nearly all strings are relative Uris. So just look if the
// string starts with '/'. If so, we have a relative Uri and the path starts at position 0.
// (http.sys already trimmed leading whitespaces)
if (uriString[0] != '/')
{
// We can't check against cookedUriScheme, since http.sys allows for request http://myserver/ to
// use a request line 'GET https://myserver/' (note http vs. https). Therefore check if the
// Uri starts with either http:// or https://.
int authorityStartIndex = 0;
if (uriString.StartsWith("http://", StringComparison.OrdinalIgnoreCase))
{
authorityStartIndex = 7;
}
else if (uriString.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
{
authorityStartIndex = 8;
}
if (authorityStartIndex > 0)
{
// we have an absolute Uri. Find out where the authority ends and the path begins.
// Note that Uris like "http://server?query=value/1/2" are invalid according to RFC2616
// and http.sys behavior: If the Uri contains a query, there must be at least one '/'
// between the authority and the '?' character: It's safe to just look for the first
// '/' after the authority to determine the beginning of the path.
pathStartIndex = uriString.IndexOf('/', authorityStartIndex);
if (pathStartIndex == -1)
{
// e.g. for request lines like: 'GET http://myserver' (no final '/')
pathStartIndex = uriString.Length;
}
}
else
{
// RFC2616: Request-URI = "*" | absoluteURI | abs_path | authority
// 'authority' can only be used with CONNECT which is never received by HttpListener.
// I.e. if we don't have an absolute path (must start with '/') and we don't have
// an absolute Uri (must start with http:// or https://), then 'uriString' must be '*'.
Debug.Assert((uriString.Length == 1) && (uriString[0] == '*'), "Unknown request Uri string format",
"Request Uri string is not an absolute Uri, absolute path, or '*': {0}", uriString);
// Should we ever get here, be consistent with 2.0/3.5 behavior: just add an initial
// slash to the string and treat it as a path:
uriString = "/" + uriString;
}
}
// Find end of path: The path is terminated by
// - the first '?' character
// - the first '#' character: This is never the case here, since http.sys won't accept
// Uris containing fragments. Also, RFC2616 doesn't allow fragments in request Uris.
// - end of Uri string
int queryIndex = uriString.IndexOf('?');
if (queryIndex == -1)
{
queryIndex = uriString.Length;
}
// will always return a != null string.
return AddSlashToAsteriskOnlyPath(uriString.Substring(pathStartIndex, queryIndex - pathStartIndex));
}
