res_http_websocket: Create a websocket client

Added a websocket server client in Asterisk. Asterisk has a websocket server,
but not a client. The ability to have Asterisk be able to connect to a websocket
server can potentially be useful for future work (for instance this could allow
ARI to connect back to some external system, although more work would be needed
in order to incorporate that).

Also a couple of things to note - proxy connection support has not been
implemented and there is limited http response code handling (basically, it is
connect or not).

Also added an initial new URI handling mechanism to core.  Internet type URI's
are parsed into a data structure that contains pointers to the various parts of
the URI.

(closes issue ASTERISK-23742)
Reported by: Kevin Harwell
Review: https://reviewboard.asterisk.org/r/3541/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@415223 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/http.h

@@ -225,4 +225,63 @@ struct ast_json;
 struct ast_json *ast_http_get_json(
 	struct ast_tcptls_session_instance *ser, struct ast_variable *headers);
 
+/*!\brief Parse the http response status line.
+ *
+ * \param buf the http response line information
+ * \param version the expected http version (e.g. HTTP/1.1)
+ * \param code the expected status code
+ * \return -1 if version didn't match or status code conversion fails.
+ * \return status code (>0)
+ * \since 13
+ */
+int ast_http_response_status_line(const char *buf, const char *version, int code);
+
+/*!\brief Parse a header into the given name/value strings.
+ *
+ * \note This modifies the given buffer and the out parameters point (not
+ *       allocated) to the start of the header name and header value,
+ *       respectively.
+ *
+ * \param buf a string containing the name/value to point to
+ * \param name out parameter pointing to the header name
+ * \param value out parameter pointing to header value
+ * \return -1 if buf is empty
+ * \return 0 if buf could be separated into into name and value
+ * \return 1 if name or value portion don't exist
+ * \since 13
+ */
+int ast_http_header_parse(char *buf, char **name, char **value);
+
+/*!\brief Check if the header and value match (case insensitive) their
+ *        associated expected values.
+ *
+ * \param name header name to check
+ * \param expected_name the expected name of the header
+ * \param value header value to check
+ * \param expected_value the expected value of the header
+ * \return 0 if the name and expected name do not match
+ * \return -1 if the value and expected value do not match
+ * \return 1 if the both the name and value match their expected value
+ * \since 13
+ */
+int ast_http_header_match(const char *name, const char *expected_name,
+			  const char *value, const char *expected_value);
+
+/*!\brief Check if the header name matches the expected header name.  If so,
+ *        then check to see if the value can be located in the expected value.
+ *
+ * \note Both header and value checks are case insensitive.
+ *
+ * \param name header name to check
+ * \param expected_name the expected name of the header
+ * \param value header value to check if in expected value
+ * \param expected_value the expected value(s)
+ * \return 0 if the name and expected name do not match
+ * \return -1 if the value and is not in the expected value
+ * \return 1 if the name matches expected name and value is in expected value
+ * \since 13
+ */
+int ast_http_header_match_in(const char *name, const char *expected_name,
+			     const char *value, const char *expected_value);
+
 #endif /* _ASTERISK_SRV_H */