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https://github.com/SerenityOS/serenity
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LookupServer: Port to LibCore
This commit is contained in:
Sergey Bugaev
Andreas Kling
parent
9eaac26eda
commit
821ed8367b
313
Servers/LookupServer/LookupServer.cpp
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313
Servers/LookupServer/LookupServer.cpp
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@ -0,0 +1,313 @@
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#include "LookupServer.h"
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#include "DNSPacket.h"
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#include "DNSRecord.h"
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#include <AK/BufferStream.h>
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#include <AK/ByteBuffer.h>
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#include <AK/HashMap.h>
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#include <AK/String.h>
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#include <AK/StringBuilder.h>
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#include <Kernel/Net/IPv4.h>
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#include <LibCore/CConfigFile.h>
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#include <LibCore/CEventLoop.h>
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#include <LibCore/CFile.h>
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#include <LibCore/CLocalServer.h>
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#include <LibCore/CLocalSocket.h>
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#include <LibCore/CSyscallUtils.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/select.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <time.h>
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#include <unistd.h>
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#define T_A 1
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#define T_NS 2
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#define T_CNAME 5
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#define T_SOA 6
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#define T_PTR 12
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#define T_MX 15
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#define C_IN 1
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LookupServer::LookupServer()
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{
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auto config = CConfigFile::get_for_system("LookupServer");
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dbg() << "Using network config file at " << config->file_name();
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m_dns_ip = config->read_entry("DNS", "IPAddress", "127.0.0.53");
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load_etc_hosts();
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m_local_server = CLocalServer::construct(this);
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m_local_server->on_ready_to_accept = [this]() {
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auto socket = m_local_server->accept();
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socket->on_ready_to_read = [this, socket]() {
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service_client(socket);
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RefPtr<CLocalSocket> keeper = socket;
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const_cast<CLocalSocket&>(*socket).on_ready_to_read = []{};
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};
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};
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bool ok = m_local_server->listen("/tmp/.LookupServer-socket");
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ASSERT(ok);
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}
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void LookupServer::load_etc_hosts()
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{
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dbg() << "Loading hosts from /etc/hosts";
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auto file = CFile::construct("/etc/hosts");
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if (!file->open(CIODevice::ReadOnly))
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return;
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while (!file->eof()) {
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auto line = file->read_line(1024);
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if (line.is_empty())
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break;
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auto str_line = String((const char*)line.data(), line.size() - 1, Chomp);
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auto fields = str_line.split('\t');
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auto sections = fields[0].split('.');
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IPv4Address addr {
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(u8)atoi(sections[0].characters()),
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(u8)atoi(sections[1].characters()),
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(u8)atoi(sections[2].characters()),
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(u8)atoi(sections[3].characters()),
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};
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auto name = fields[1];
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m_dns_custom_hostnames.set(name, addr.to_string());
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IPv4Address reverse_addr {
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(u8)atoi(sections[3].characters()),
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(u8)atoi(sections[2].characters()),
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(u8)atoi(sections[1].characters()),
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(u8)atoi(sections[0].characters()),
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};
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StringBuilder builder;
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builder.append(reverse_addr.to_string());
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builder.append(".in-addr.arpa");
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m_dns_custom_hostnames.set(builder.to_string(), name);
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}
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}
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void LookupServer::service_client(RefPtr<CLocalSocket> socket)
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{
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u8 client_buffer[1024];
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int nrecv = socket->read(client_buffer, sizeof(client_buffer) - 1);
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if (nrecv < 0) {
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perror("read");
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return;
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}
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client_buffer[nrecv] = '\0';
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char lookup_type = client_buffer[0];
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if (lookup_type != 'L' && lookup_type != 'R') {
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dbg() << "Invalid lookup_type " << lookup_type;
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return;
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}
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auto hostname = String((const char*)client_buffer + 1, nrecv - 1, Chomp);
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dbg() << "Got request for '" << hostname << "' (using IP " << m_dns_ip << ")";
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Vector<String> responses;
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if (auto known_host = m_dns_custom_hostnames.get(hostname)) {
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responses.append(known_host.value());
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} else if (!hostname.is_empty()) {
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bool did_timeout;
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int retries = 3;
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do {
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did_timeout = false;
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if (lookup_type == 'L')
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responses = lookup(hostname, did_timeout, T_A);
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else if (lookup_type == 'R')
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responses = lookup(hostname, did_timeout, T_PTR);
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if (!did_timeout)
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break;
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} while (--retries);
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if (did_timeout) {
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fprintf(stderr, "LookupServer: Out of retries :(\n");
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return;
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}
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}
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if (responses.is_empty()) {
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int nsent = socket->write("Not found.\n");
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if (nsent < 0)
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perror("write");
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return;
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}
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for (auto& response : responses) {
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auto line = String::format("%s\n", response.characters());
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int nsent = socket->write(line);
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if (nsent < 0) {
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perror("write");
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break;
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}
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}
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}
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String LookupServer::parse_dns_name(const u8* data, int& offset, int max_offset)
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{
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Vector<char, 128> buf;
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while (offset < max_offset) {
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u8 ch = data[offset];
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if (ch == '\0') {
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++offset;
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break;
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}
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if ((ch & 0xc0) == 0xc0) {
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ASSERT_NOT_REACHED();
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// FIXME: Parse referential names.
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offset += 2;
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}
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for (int i = 0; i < ch; ++i) {
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buf.append(data[offset + i + 1]);
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}
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buf.append('.');
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offset += ch + 1;
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}
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return String::copy(buf);
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}
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Vector<String> LookupServer::lookup(const String& hostname, bool& did_timeout, unsigned short record_type)
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{
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if (auto it = m_lookup_cache.find(hostname); it != m_lookup_cache.end()) {
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auto& cached_lookup = it->value;
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if (cached_lookup.record_type == record_type && cached_lookup.timestamp < (time(nullptr) + 60)) {
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return it->value.responses;
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}
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m_lookup_cache.remove(it);
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}
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DNSPacket request_header;
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request_header.set_id(get_next_id());
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request_header.set_is_query();
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request_header.set_opcode(0);
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request_header.set_truncated(false);
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request_header.set_recursion_desired(true);
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request_header.set_question_count(1);
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auto buffer = ByteBuffer::create_uninitialized(1024);
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{
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BufferStream stream(buffer);
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stream << ByteBuffer::wrap(&request_header, sizeof(request_header));
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auto parts = hostname.split('.');
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for (auto& part : parts) {
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stream << (u8)part.length();
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stream << part;
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}
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stream << '\0';
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stream << htons(record_type);
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stream << htons(C_IN);
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stream.snip();
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}
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int fd = socket(AF_INET, SOCK_DGRAM, 0);
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if (fd < 0) {
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perror("socket");
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return {};
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}
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struct timeval timeout {
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1, 0
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};
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int rc = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
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if (rc < 0) {
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perror("setsockopt");
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close(fd);
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return {};
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}
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struct sockaddr_in dst_addr;
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memset(&dst_addr, 0, sizeof(dst_addr));
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dst_addr.sin_family = AF_INET;
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dst_addr.sin_port = htons(53);
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rc = inet_pton(AF_INET, m_dns_ip.characters(), &dst_addr.sin_addr);
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int nsent = sendto(fd, buffer.data(), buffer.size(), 0, (const struct sockaddr*)&dst_addr, sizeof(dst_addr));
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if (nsent < 0) {
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perror("sendto");
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return {};
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}
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ASSERT(nsent == buffer.size());
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struct sockaddr_in src_addr;
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socklen_t src_addr_len = sizeof(src_addr);
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u8 response_buffer[4096];
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ssize_t nrecv = recvfrom(fd, response_buffer, sizeof(response_buffer) - 1, 0, (struct sockaddr*)&src_addr, &src_addr_len);
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if (nrecv < 0) {
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if (errno == EAGAIN) {
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did_timeout = true;
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} else {
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perror("recvfrom");
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}
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close(fd);
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return {};
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}
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close(fd);
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response_buffer[nrecv] = '\0';
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if (nrecv < (int)sizeof(DNSPacket)) {
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dbgprintf("LookupServer: Response not big enough (%d) to be a DNS packet :(\n", nrecv);
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return {};
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}
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auto& response_header = *(DNSPacket*)(response_buffer);
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dbgprintf("Got response (ID: %u)\n", response_header.id());
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dbgprintf(" Question count: %u\n", response_header.question_count());
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dbgprintf(" Answer count: %u\n", response_header.answer_count());
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dbgprintf(" Authority count: %u\n", response_header.authority_count());
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dbgprintf("Additional count: %u\n", response_header.additional_count());
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if (response_header.id() != request_header.id()) {
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dbgprintf("LookupServer: ID mismatch (%u vs %u) :(\n", response_header.id(), request_header.id());
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return {};
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}
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if (response_header.question_count() != 1) {
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dbgprintf("LookupServer: Question count (%u vs %u) :(\n", response_header.question_count(), request_header.question_count());
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return {};
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}
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if (response_header.answer_count() < 1) {
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dbgprintf("LookupServer: Not enough answers (%u) :(\n", response_header.answer_count());
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return {};
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}
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int offset = 0;
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auto question = parse_dns_name((const u8*)response_header.payload(), offset, nrecv);
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offset += 4;
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Vector<String> addresses;
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for (u16 i = 0; i < response_header.answer_count(); ++i) {
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auto& record = *(const DNSRecord*)(&((const u8*)response_header.payload())[offset]);
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dbgprintf("LookupServer: Answer #%u: (question: %s), type=%u, ttl=%u, length=%u, data=",
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i,
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question.characters(),
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record.type(),
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record.ttl(),
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record.data_length());
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offset += sizeof(DNSRecord) + record.data_length();
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if (record.type() == T_PTR) {
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int dummy = 0;
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auto name = parse_dns_name((const u8*)record.data(), dummy, record.data_length());
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dbgprintf("%s\n", name.characters());
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addresses.append(name);
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} else if (record.type() == T_A) {
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auto ipv4_address = IPv4Address((const u8*)record.data());
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dbgprintf("%s\n", ipv4_address.to_string().characters());
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addresses.append(ipv4_address.to_string());
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} else {
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dbgprintf("(unimplemented)\n");
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dbgprintf("LookupServer: FIXME: Handle record type %u\n", record.type());
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}
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// FIXME: Parse some other record types perhaps?
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}
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m_lookup_cache.set(hostname, { time(nullptr), record_type, addresses });
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return addresses;
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}
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36
Servers/LookupServer/LookupServer.h
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36
Servers/LookupServer/LookupServer.h
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@ -0,0 +1,36 @@
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#pragma once
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#include <AK/HashMap.h>
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#include <AK/RefPtr.h>
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#include <AK/String.h>
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#include <LibCore/CObject.h>
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class CLocalSocket;
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class CLocalServer;
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class LookupServer final : public CObject {
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C_OBJECT(LookupServer)
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public:
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LookupServer();
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private:
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void load_etc_hosts();
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void service_client(RefPtr<CLocalSocket>);
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static String parse_dns_name(const u8* data, int& offset, int max_offset);
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Vector<String> lookup(const String& hostname, bool& did_timeout, unsigned short record_type);
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u16 get_next_id() { return ++m_next_id; }
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struct CachedLookup {
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time_t timestamp { 0 };
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unsigned short record_type { 0 };
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Vector<String> responses;
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};
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RefPtr<CLocalServer> m_local_server;
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u16 m_next_id { 0 };
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String m_dns_ip;
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HashMap<String, String> m_dns_custom_hostnames;
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HashMap<String, CachedLookup> m_lookup_cache;
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};
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@ -1,6 +1,7 @@
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include ../../Makefile.common
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LOOKUPSERVER_OBJS = \
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LookupServer.o \
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main.o
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APP = LookupServer
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@ -1,375 +1,13 @@
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#include "DNSPacket.h"
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#include "DNSRecord.h"
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#include <AK/String.h>
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#include <AK/BufferStream.h>
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#include <AK/ByteBuffer.h>
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#include <AK/HashMap.h>
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#include <AK/StringBuilder.h>
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#include <Kernel/Net/IPv4.h>
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#include <LibCore/CConfigFile.h>
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#include <LibCore/CFile.h>
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#include <LibCore/CSyscallUtils.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/select.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <time.h>
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#include <unistd.h>
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#define T_A 1
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#define T_NS 2
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#define T_CNAME 5
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#define T_SOA 6
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#define T_PTR 12
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#define T_MX 15
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#define C_IN 1
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struct CachedLookup {
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time_t timestamp { 0 };
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unsigned short record_type { 0 };
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Vector<String> responses;
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};
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static HashMap<String, CachedLookup> lookup_cache;
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static HashMap<String, String> dns_custom_hostnames;
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static Vector<String> lookup(const String& hostname, bool& did_timeout, const String& DNS_IP, unsigned short record_type);
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static String parse_dns_name(const u8*, int& offset, int max_offset);
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static void load_etc_hosts()
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{
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dbgprintf("LookupServer: Loading hosts from /etc/hosts\n");
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auto file = CFile::construct("/etc/hosts");
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if (!file->open(CIODevice::ReadOnly))
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return;
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while (!file->eof()) {
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auto line = file->read_line(1024);
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if (line.is_empty())
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break;
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auto str_line = String((const char*)line.data(), line.size() - 1, Chomp);
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auto fields = str_line.split('\t');
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auto sections = fields[0].split('.');
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IPv4Address addr {
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(u8)atoi(sections[0].characters()),
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(u8)atoi(sections[1].characters()),
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(u8)atoi(sections[2].characters()),
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(u8)atoi(sections[3].characters()),
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};
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auto name = fields[1];
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dns_custom_hostnames.set(name, addr.to_string());
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IPv4Address reverse_addr {
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(u8)atoi(sections[3].characters()),
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(u8)atoi(sections[2].characters()),
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(u8)atoi(sections[1].characters()),
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(u8)atoi(sections[0].characters()),
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};
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StringBuilder builder;
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builder.append(reverse_addr.to_string());
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builder.append(".in-addr.arpa");
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dns_custom_hostnames.set(builder.to_string(), name);
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}
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}
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#include "LookupServer.h"
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#include <LibCore/CEventLoop.h>
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int main(int argc, char** argv)
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{
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(void)argc;
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(void)argv;
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unlink("/tmp/.LookupServer-socket");
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CEventLoop event_loop;
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LookupServer server;
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auto config = CConfigFile::get_for_system("LookupServer");
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dbgprintf("LookupServer: Using network config file at %s.\n",
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config->file_name().characters());
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auto DNS_IP = config->read_entry("DNS", "IPAddress", "127.0.0.53");
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load_etc_hosts();
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int server_fd = socket(AF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
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if (server_fd < 0) {
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perror("socket");
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return 1;
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}
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sockaddr_un address;
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address.sun_family = AF_LOCAL;
|
||||
strcpy(address.sun_path, "/tmp/.LookupServer-socket");
|
||||
|
||||
int rc = bind(server_fd, (const sockaddr*)&address, sizeof(address));
|
||||
if (rc < 0) {
|
||||
perror("bind");
|
||||
return 1;
|
||||
}
|
||||
rc = listen(server_fd, 5);
|
||||
if (rc < 0) {
|
||||
perror("listen");
|
||||
return 1;
|
||||
}
|
||||
|
||||
for (;;) {
|
||||
fd_set rfds;
|
||||
FD_ZERO(&rfds);
|
||||
FD_SET(server_fd, &rfds);
|
||||
rc = CSyscallUtils::safe_syscall(select, server_fd + 1, &rfds, nullptr, nullptr, nullptr);
|
||||
if (rc < 1) {
|
||||
perror("select");
|
||||
return 1;
|
||||
}
|
||||
|
||||
sockaddr_un client_address;
|
||||
socklen_t client_address_size = sizeof(client_address);
|
||||
int client_fd = accept(server_fd, (sockaddr*)&client_address, &client_address_size);
|
||||
if (client_fd < 0) {
|
||||
perror("accept");
|
||||
continue;
|
||||
}
|
||||
|
||||
FD_ZERO(&rfds);
|
||||
FD_SET(client_fd, &rfds);
|
||||
rc = select(client_fd + 1, &rfds, nullptr, nullptr, nullptr);
|
||||
if (rc < 1) {
|
||||
perror("select");
|
||||
return 1;
|
||||
}
|
||||
|
||||
char client_buffer[1024];
|
||||
int nrecv = read(client_fd, client_buffer, sizeof(client_buffer) - 1);
|
||||
if (nrecv < 0) {
|
||||
perror("recv");
|
||||
close(client_fd);
|
||||
continue;
|
||||
}
|
||||
|
||||
client_buffer[nrecv] = '\0';
|
||||
|
||||
char lookup_type = client_buffer[0];
|
||||
if (lookup_type != 'L' && lookup_type != 'R') {
|
||||
dbgprintf("LookupServer: Invalid lookup_type '%c'\n", lookup_type);
|
||||
close(client_fd);
|
||||
continue;
|
||||
}
|
||||
auto hostname = String(client_buffer + 1, nrecv - 1, Chomp);
|
||||
dbgprintf("LookupServer: Got request for '%s' (using IP %s)\n",
|
||||
hostname.characters(),
|
||||
DNS_IP.characters());
|
||||
|
||||
Vector<String> responses;
|
||||
|
||||
if (auto known_host = dns_custom_hostnames.get(hostname)) {
|
||||
responses.append(known_host.value());
|
||||
} else if (!hostname.is_empty()) {
|
||||
bool did_timeout;
|
||||
int retries = 3;
|
||||
do {
|
||||
did_timeout = false;
|
||||
if (lookup_type == 'L')
|
||||
responses = lookup(hostname, did_timeout, DNS_IP, T_A);
|
||||
else if (lookup_type == 'R')
|
||||
responses = lookup(hostname, did_timeout, DNS_IP, T_PTR);
|
||||
if (!did_timeout)
|
||||
break;
|
||||
} while (--retries);
|
||||
if (did_timeout) {
|
||||
fprintf(stderr, "LookupServer: Out of retries :(\n");
|
||||
close(client_fd);
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
if (responses.is_empty()) {
|
||||
int nsent = write(client_fd, "Not found.\n", sizeof("Not found.\n"));
|
||||
if (nsent < 0)
|
||||
perror("write");
|
||||
close(client_fd);
|
||||
continue;
|
||||
}
|
||||
for (auto& response : responses) {
|
||||
auto line = String::format("%s\n", response.characters());
|
||||
int nsent = write(client_fd, line.characters(), line.length());
|
||||
if (nsent < 0) {
|
||||
perror("write");
|
||||
break;
|
||||
}
|
||||
}
|
||||
close(client_fd);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static u16 get_next_id()
|
||||
{
|
||||
static u16 s_next_id = 0;
|
||||
return ++s_next_id;
|
||||
}
|
||||
|
||||
Vector<String> lookup(const String& hostname, bool& did_timeout, const String& DNS_IP, unsigned short record_type)
|
||||
{
|
||||
if (auto it = lookup_cache.find(hostname); it != lookup_cache.end()) {
|
||||
auto& cached_lookup = it->value;
|
||||
if (cached_lookup.record_type == record_type && cached_lookup.timestamp < (time(nullptr) + 60)) {
|
||||
return it->value.responses;
|
||||
}
|
||||
lookup_cache.remove(it);
|
||||
}
|
||||
|
||||
DNSPacket request_header;
|
||||
request_header.set_id(get_next_id());
|
||||
request_header.set_is_query();
|
||||
request_header.set_opcode(0);
|
||||
request_header.set_truncated(false);
|
||||
request_header.set_recursion_desired(true);
|
||||
request_header.set_question_count(1);
|
||||
|
||||
auto buffer = ByteBuffer::create_uninitialized(1024);
|
||||
{
|
||||
BufferStream stream(buffer);
|
||||
|
||||
stream << ByteBuffer::wrap(&request_header, sizeof(request_header));
|
||||
auto parts = hostname.split('.');
|
||||
for (auto& part : parts) {
|
||||
stream << (u8)part.length();
|
||||
stream << part;
|
||||
}
|
||||
stream << '\0';
|
||||
stream << htons(record_type);
|
||||
stream << htons(C_IN);
|
||||
stream.snip();
|
||||
}
|
||||
|
||||
int fd = socket(AF_INET, SOCK_DGRAM, 0);
|
||||
if (fd < 0) {
|
||||
perror("socket");
|
||||
return {};
|
||||
}
|
||||
|
||||
struct timeval timeout {
|
||||
1, 0
|
||||
};
|
||||
int rc = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
|
||||
if (rc < 0) {
|
||||
perror("setsockopt");
|
||||
close(fd);
|
||||
return {};
|
||||
}
|
||||
|
||||
struct sockaddr_in dst_addr;
|
||||
memset(&dst_addr, 0, sizeof(dst_addr));
|
||||
|
||||
dst_addr.sin_family = AF_INET;
|
||||
dst_addr.sin_port = htons(53);
|
||||
rc = inet_pton(AF_INET, DNS_IP.characters(), &dst_addr.sin_addr);
|
||||
|
||||
int nsent = sendto(fd, buffer.data(), buffer.size(), 0, (const struct sockaddr*)&dst_addr, sizeof(dst_addr));
|
||||
if (nsent < 0) {
|
||||
perror("sendto");
|
||||
return {};
|
||||
}
|
||||
ASSERT(nsent == buffer.size());
|
||||
|
||||
struct sockaddr_in src_addr;
|
||||
socklen_t src_addr_len = sizeof(src_addr);
|
||||
u8 response_buffer[4096];
|
||||
ssize_t nrecv = recvfrom(fd, response_buffer, sizeof(response_buffer) - 1, 0, (struct sockaddr*)&src_addr, &src_addr_len);
|
||||
if (nrecv < 0) {
|
||||
if (errno == EAGAIN) {
|
||||
did_timeout = true;
|
||||
} else {
|
||||
perror("recvfrom");
|
||||
}
|
||||
close(fd);
|
||||
return {};
|
||||
}
|
||||
close(fd);
|
||||
|
||||
response_buffer[nrecv] = '\0';
|
||||
|
||||
if (nrecv < (int)sizeof(DNSPacket)) {
|
||||
dbgprintf("LookupServer: Response not big enough (%d) to be a DNS packet :(\n", nrecv);
|
||||
return {};
|
||||
}
|
||||
|
||||
auto& response_header = *(DNSPacket*)(response_buffer);
|
||||
dbgprintf("Got response (ID: %u)\n", response_header.id());
|
||||
dbgprintf(" Question count: %u\n", response_header.question_count());
|
||||
dbgprintf(" Answer count: %u\n", response_header.answer_count());
|
||||
dbgprintf(" Authority count: %u\n", response_header.authority_count());
|
||||
dbgprintf("Additional count: %u\n", response_header.additional_count());
|
||||
|
||||
if (response_header.id() != request_header.id()) {
|
||||
dbgprintf("LookupServer: ID mismatch (%u vs %u) :(\n", response_header.id(), request_header.id());
|
||||
return {};
|
||||
}
|
||||
if (response_header.question_count() != 1) {
|
||||
dbgprintf("LookupServer: Question count (%u vs %u) :(\n", response_header.question_count(), request_header.question_count());
|
||||
return {};
|
||||
}
|
||||
if (response_header.answer_count() < 1) {
|
||||
dbgprintf("LookupServer: Not enough answers (%u) :(\n", response_header.answer_count());
|
||||
return {};
|
||||
}
|
||||
|
||||
int offset = 0;
|
||||
auto question = parse_dns_name((const u8*)response_header.payload(), offset, nrecv);
|
||||
offset += 4;
|
||||
|
||||
Vector<String> addresses;
|
||||
|
||||
for (u16 i = 0; i < response_header.answer_count(); ++i) {
|
||||
auto& record = *(const DNSRecord*)(&((const u8*)response_header.payload())[offset]);
|
||||
dbgprintf("LookupServer: Answer #%u: (question: %s), type=%u, ttl=%u, length=%u, data=",
|
||||
i,
|
||||
question.characters(),
|
||||
record.type(),
|
||||
record.ttl(),
|
||||
record.data_length());
|
||||
|
||||
offset += sizeof(DNSRecord) + record.data_length();
|
||||
if (record.type() == T_PTR) {
|
||||
int dummy = 0;
|
||||
auto name = parse_dns_name((const u8*)record.data(), dummy, record.data_length());
|
||||
dbgprintf("%s\n", name.characters());
|
||||
addresses.append(name);
|
||||
} else if (record.type() == T_A) {
|
||||
auto ipv4_address = IPv4Address((const u8*)record.data());
|
||||
dbgprintf("%s\n", ipv4_address.to_string().characters());
|
||||
addresses.append(ipv4_address.to_string());
|
||||
} else {
|
||||
dbgprintf("(unimplemented)\n");
|
||||
dbgprintf("LookupServer: FIXME: Handle record type %u\n", record.type());
|
||||
}
|
||||
// FIXME: Parse some other record types perhaps?
|
||||
}
|
||||
|
||||
lookup_cache.set(hostname, { time(nullptr), record_type, addresses });
|
||||
return addresses;
|
||||
}
|
||||
|
||||
static String parse_dns_name(const u8* data, int& offset, int max_offset)
|
||||
{
|
||||
Vector<char, 128> buf;
|
||||
while (offset < max_offset) {
|
||||
u8 ch = data[offset];
|
||||
if (ch == '\0') {
|
||||
++offset;
|
||||
break;
|
||||
}
|
||||
if ((ch & 0xc0) == 0xc0) {
|
||||
ASSERT_NOT_REACHED();
|
||||
// FIXME: Parse referential names.
|
||||
offset += 2;
|
||||
}
|
||||
for (int i = 0; i < ch; ++i) {
|
||||
buf.append(data[offset + i + 1]);
|
||||
}
|
||||
buf.append('.');
|
||||
offset += ch + 1;
|
||||
}
|
||||
return String::copy(buf);
|
||||
return event_loop.exec();
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue