anotherim-desktop/xmpp-vala/src/core/stanza_reader.vala
2020-06-28 11:53:43 +02:00

299 lines
9.9 KiB
Vala

using Gee;
namespace Xmpp {
public const string XMLNS_URI = "http://www.w3.org/2000/xmlns/";
public const string XML_URI = "http://www.w3.org/XML/1998/namespace";
public const string JABBER_URI = "jabber:client";
public errordomain XmlError {
NS_DICT_ERROR,
UNSUPPORTED,
EOF,
BAD_XML,
IO,
TLS
}
public class StanzaReader {
private static int BUFFER_MAX = 4096;
private InputStream? input;
private uint8[] buffer;
private int buffer_fill = 0;
private int buffer_pos = 0;
private Cancellable cancellable = new Cancellable();
private NamespaceState ns_state = new NamespaceState();
public StanzaReader.for_buffer(uint8[] buffer) {
this.buffer = buffer;
this.buffer_fill = buffer.length;
}
public StanzaReader.for_string(string s) {
this.for_buffer(s.data);
}
public StanzaReader.for_stream(InputStream input) {
this.input = input;
buffer = new uint8[BUFFER_MAX];
}
public void cancel() {
cancellable.cancel();
}
private async void update_buffer() throws XmlError {
try {
InputStream? input = this.input;
if (input == null) throw new XmlError.EOF("No input stream specified and end of buffer reached.");
if (cancellable.is_cancelled()) throw new XmlError.EOF("Input stream is canceled.");
buffer_fill = (int) yield ((!)input).read_async(buffer, GLib.Priority.DEFAULT, cancellable);
if (buffer_fill == 0) throw new XmlError.EOF("End of input stream reached.");
buffer_pos = 0;
} catch (GLib.IOError e) {
throw new XmlError.IO("GLib.IOError: %s".printf(e.message));
}
}
private async char read_single() throws XmlError {
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
return (char) buffer[buffer_pos++];
}
private async char peek_single() throws XmlError {
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
return (char) buffer[buffer_pos];
}
private bool is_ws(uint8 what) {
return what == ' ' || what == '\t' || what == '\r' || what == '\n';
}
private void skip_single() {
buffer_pos++;
}
private async void skip_until_non_ws() throws XmlError {
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
while (is_ws(buffer[buffer_pos])) {
buffer_pos++;
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
}
}
private async string read_until_ws() throws XmlError {
var res = new StringBuilder();
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
while (!is_ws(buffer[buffer_pos])) {
res.append_c((char) buffer[buffer_pos++]);
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
}
return res.str;
}
private async string read_until_char_or_ws(char x, char y = 0) throws XmlError {
var res = new StringBuilder();
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
while (buffer[buffer_pos] != x && buffer[buffer_pos] != y && !is_ws(buffer[buffer_pos])) {
res.append_c((char) buffer[buffer_pos++]);
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
}
return res.str;
}
private async string read_until_char(char x) throws XmlError {
var res = new StringBuilder();
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
while (buffer[buffer_pos] != x) {
res.append_c((char) buffer[buffer_pos++]);
if (buffer_pos >= buffer_fill) {
yield update_buffer();
}
}
return res.str;
}
private async StanzaAttribute read_attribute() throws XmlError {
var res = new StanzaAttribute();
res.name = yield read_until_char_or_ws('=');
if ((yield read_single()) == '=') {
var quot = yield peek_single();
if (quot == '\'' || quot == '"') {
skip_single();
res.encoded_val = yield read_until_char(quot);
skip_single();
} else {
res.encoded_val = yield read_until_ws();
}
}
return res;
}
private void handle_entry_ns(StanzaEntry entry, string default_uri = ns_state.current_ns_uri) throws XmlError {
if (entry.ns_uri != null) return;
if (entry.name.contains(":")) {
var split = entry.name.split(":");
entry.ns_uri = ns_state.find_uri(split[0]);
entry.name = split[1];
} else {
entry.ns_uri = default_uri;
}
}
private void handle_stanza_ns(StanzaNode res) throws XmlError {
foreach (StanzaAttribute attr in res.attributes) {
if (attr.name == "xmlns" && attr.val != null) {
attr.ns_uri = XMLNS_URI;
ns_state.set_current((!)attr.val);
} else if (attr.name.contains(":") && attr.val != null) {
var split = attr.name.split(":");
if (split[0] == "xmlns") {
attr.ns_uri = XMLNS_URI;
attr.name = split[1];
ns_state.add_assoc((!)attr.val, attr.name);
}
}
}
handle_entry_ns(res);
foreach (StanzaAttribute attr in res.attributes) {
handle_entry_ns(attr, res.ns_uri ?? ns_state.current_ns_uri);
}
}
public async StanzaNode read_node_start() throws XmlError {
var res = new StanzaNode();
res.attributes = new ArrayList<StanzaAttribute>();
var eof = false;
if ((yield peek_single()) == '<') skip_single();
if ((yield peek_single()) == '?') res.pseudo = true;
if ((yield peek_single()) == '/') {
eof = true;
skip_single();
res.name = yield read_until_char_or_ws('>');
while ((yield peek_single()) != '>') {
skip_single();
}
skip_single();
res.has_nodes = false;
res.pseudo = false;
handle_stanza_ns(res);
return res;
}
res.name = yield read_until_char_or_ws('>', '/');
yield skip_until_non_ws();
char next_char = yield peek_single();
while (next_char != '/' && next_char != '>' && next_char != '?') {
res.attributes.add(yield read_attribute());
yield skip_until_non_ws();
next_char = yield peek_single();
}
if ((yield read_single()) == '/' || res.pseudo) {
res.has_nodes = false;
skip_single();
} else {
res.has_nodes = true;
}
handle_stanza_ns(res);
return res;
}
public async StanzaNode read_text_node() throws XmlError {
var res = new StanzaNode();
res.name = "#text";
res.ns_uri = ns_state.current_ns_uri;
res.encoded_val = (yield read_until_char('<'));
return res;
}
public async StanzaNode read_root_node() throws XmlError {
yield skip_until_non_ws();
if ((yield peek_single()) == '<') {
var res = yield read_node_start();
if (res.pseudo) {
return yield read_root_node();
}
return res;
} else {
throw new XmlError.BAD_XML("Content before root node");
}
}
public async StanzaNode read_stanza_node() throws XmlError {
try {
ns_state = ns_state.push();
var res = yield read_node_start();
if (res.has_nodes) {
bool finish_node_seen = false;
StanzaNode? text_node = null;
do {
text_node = yield read_text_node();
if ((yield peek_single()) == '<') {
skip_single();
if ((yield peek_single()) == '/') {
skip_single();
string desc = yield read_until_char('>');
skip_single();
if (desc.contains(":")) {
var split = desc.split(":");
if (split[0] != ns_state.find_name((!)res.ns_uri)) throw new XmlError.BAD_XML("");
if (split[1] != res.name) throw new XmlError.BAD_XML("");
} else {
if (ns_state.current_ns_uri != res.ns_uri) throw new XmlError.BAD_XML("");
if (desc != res.name) throw new XmlError.BAD_XML("");
}
finish_node_seen = true;
} else {
res.sub_nodes.add(yield read_stanza_node());
}
}
} while (!finish_node_seen);
if (res.sub_nodes.size == 0) {
if (text_node == null || text_node.val.length == 0) {
res.has_nodes = false;
} else {
res.sub_nodes.add(text_node);
}
}
}
ns_state = ns_state.pop();
return res;
} catch (XmlError e) {
uint8[] buffer_cpy = new uint8[buffer.length + 1];
Memory.copy(buffer_cpy, buffer, buffer.length);
warning("XmlError at: %s".printf((string)buffer_cpy) + "\n");
throw e;
}
}
public async StanzaNode read_node() throws XmlError {
yield skip_until_non_ws();
if ((yield peek_single()) == '<') {
return yield read_stanza_node();
} else {
return yield read_text_node();
}
}
}
}