/** @file
Parser: @b websocket parser class.
Copyright (c) 2001-2026 Art. Lebedev Studio (https://www.artlebedev.com)
Authors: Konstantin Morshnev <moko@design.ru>
*/
#include "pa_vmethod_frame.h"
#include "pa_request.h"
#include "pa_vhash.h"
#include "pa_vint.h"
#include "pa_vvoid.h"
#include "pa_vfile.h"
#include "pa_vresponse.h"
#include "pa_charsets.h"
#include "pa_websocket.h"
volatile const char * IDENT_WEBSOCKET_C="$Id: websocket.C,v 1.2 2026/10/16 15:16:21 moko Exp $" IDENT_PA_WEBSOCKET_H;
// class
class MWebsocket: public Methoded {
public:
MWebsocket();
};
// global variable
DECLARE_CLASS_VAR(websocket, new MWebsocket);
// defines
#define MAX_CONTROL_SIZE 125
#define MAX_REASON_SIZE (MAX_CONTROL_SIZE-2)
static const String::Body status_name_upper("STATUS");
static const String::Body upgrade_name_upper("UPGRADE");
static const String::Body connection_name_upper("CONNECTION");
static const String::Body accept_name_upper("SEC-WEBSOCKET-ACCEPT");
// methods
static WebSocket& get_websocket(Request& r) {
if(!r.websocket)
throw Exception("websocket", 0, "websocket is available in httpd mode only");
return *r.websocket;
}
static WebSocket& get_accepted_websocket(Request& r) {
WebSocket& result=get_websocket(r);
if(!result.accepted)
throw Exception("websocket", 0, "connection is not accepted, use ^websocket:accept[] first");
return result;
}
// text goes in UTF-8 and the string is in the source charset, tainted data is untainted as in the response
static String::C to_utf8(Request& r, const String& string) {
String::Body body=string.cstr_to_string_body_untaint(r.response.lang, r.connection(false), &r.charsets);
return Charset::transcode(String::C(body.cstr(), body.length()), r.charsets.source(), pa_UTF8_charset);
}
static void _accept(Request& r, MethodParams&) {
WebSocket& websocket=get_websocket(r);
if(websocket.accepted)
throw Exception("websocket", 0, "connection is accepted already");
if(r.response.started)
throw Exception("websocket", 0, "unable to accept: headers are already sent");
const char* accept_key=pa_websocket_accept_key(
r.request_info.method,
SAPI::Env::get(r.sapi_info, "HTTP_UPGRADE"),
SAPI::Env::get(r.sapi_info, "HTTP_CONNECTION"),
SAPI::Env::get(r.sapi_info, "HTTP_SEC_WEBSOCKET_KEY"),
SAPI::Env::get(r.sapi_info, "HTTP_SEC_WEBSOCKET_VERSION"));
// $response:fields, such as sec-websocket-protocol, are sent too
HashStringValue& fields=r.response.fields();
fields.put(status_name_upper, new VInt(101));
fields.put(upgrade_name_upper, new VString(*new String("websocket")));
fields.put(connection_name_upper, new VString(*new String("Upgrade")));
fields.put(accept_name_upper, new VString(*new String(accept_key)));
r.start(VResponse::WEBSOCKET);
websocket.start(pa_post_max_size);
}
static void _receive(Request& r, MethodParams& params) {
WebSocket& websocket=get_accepted_websocket(r);
double timeout=params.as_double(0, "timeout must be expression", r);
if(timeout<0)
throw Exception(PARSER_RUNTIME, 0, "timeout must not be negative");
WebSocket::Message message;
if(!websocket.receive(timeout*1000 < INT_MAX ? (int)(timeout*1000) : INT_MAX, message)) {
r.write(*VVoid::get());
return;
}
// the data is copied as the buffer is reused
const char* data=pa_strdup(message.data, message.size);
VHash& result=*new VHash;
HashStringValue& fields=result.hash();
if(message.opcode==WebSocket::BINARY) {
fields.put("type", new VString(*new String("binary")));
VFile& file=*new VFile;
file.set_binary(true/*tainted*/, data, message.size);
fields.put("data", &file);
} else {
String::C text=Charset::transcode(String::C(data, message.size), pa_UTF8_charset, r.charsets.source());
fields.put("type", new VString(*new String(message.opcode==WebSocket::TEXT ? "text" : "close")));
fields.put("data", new VString(*new String(text, String::L_TAINTED)));
if(message.opcode==WebSocket::CLOSE)
fields.put("code", new VInt(message.code));
}
r.write(result);
}
static void _send(Request& r, MethodParams& params) {
WebSocket& websocket=get_accepted_websocket(r);
if(VFile* file=dynamic_cast<VFile*>(¶ms[0])) {
websocket.send(WebSocket::BINARY, file->value_ptr(), file->value_size());
} else {
String::C text=to_utf8(r, params.as_string(0, "message must be string or file"));
websocket.send(WebSocket::TEXT, text.str, text.length);
}
}
static void _ping(Request& r, MethodParams& params) {
WebSocket& websocket=get_accepted_websocket(r);
String::C data;
if(params.count())
data=to_utf8(r, params.as_string(0, "data must be string"));
if(data.length>MAX_CONTROL_SIZE)
throw Exception(PARSER_RUNTIME, 0, "data is too long, it must be up to %d bytes", MAX_CONTROL_SIZE);
websocket.send(WebSocket::PING, data.str, data.length);
}
static void _close(Request& r, MethodParams& params) {
WebSocket& websocket=get_accepted_websocket(r);
int code=params.count()>0 ? params.as_int(0, "code must be int", r) : WebSocket::NORMAL;
if(!WebSocket::valid_status(code))
throw Exception(PARSER_RUNTIME, 0, "code(%d) is not valid", code);
String::C reason;
if(params.count()>1)
reason=to_utf8(r, params.as_string(1, "reason must be string"));
if(reason.length>MAX_REASON_SIZE)
throw Exception(PARSER_RUNTIME, 0, "reason is too long, it must be up to %d bytes", MAX_REASON_SIZE);
websocket.close(code, reason.str ? reason.str : "", reason.length);
}
// constructor
MWebsocket::MWebsocket(): Methoded("websocket") {
// ^accept[]
add_native_method("accept", Method::CT_STATIC, _accept, 0, 0);
// ^receive(timeout in seconds), returns message hash
add_native_method("receive", Method::CT_STATIC, _receive, 1, 1);
// ^send[string or file]
add_native_method("send", Method::CT_STATIC, _send, 1, 1);
// ^ping[] or ^ping[data]
add_native_method("ping", Method::CT_STATIC, _ping, 0, 1);
// ^close[] or ^close(code) or ^close(code;reason)
add_native_method("close", Method::CT_STATIC, _close, 0, 2);
}
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