proto_fuzzer::SmtpMockServer Class Reference

Services curl's single-connection, line-based SMTP exchange. More...

#include <smtp_mock_server.h>

Inheritance diagram for proto_fuzzer::SmtpMockServer:

Public Member Functions
	SmtpMockServer (curl::fuzzer::proto::SmtpProbeMode mode=curl::fuzzer::proto::SMTP_PROBE_DEFAULT)
	Begin without a borrowed protobuf or open socketpair.
	~SmtpMockServer () override
	Release the server-owned socketpair half after curl has returned its client descriptor.
void	ObserveState () override
	Retain protocol outcomes in coverage and introspector builds.
void	ConfigureClient (CURL *easy) const
	Apply only closed, harness-owned client controls.
Public Member Functions inherited from proto_fuzzer::PingpongMockServer
	~PingpongMockServer () override
	Release the server-owned socketpair half after curl has returned its client descriptor.
const std::string &	control_transcript () const
	Expose the bounded command capture from the most recent drive so tests can verify protocol states without coupling assertions to curl debug output.
const std::string &	uploaded_data () const
	Expose a bounded prefix of bytes drained during the most recent body phase while continuing to drain every client byte, so test observability cannot create backpressure.
std::size_t	active_pollset_probe_count () const
	Report how many requested zero-timeout multi-poll probes ran during the most recent drive.
std::size_t	writable_pollset_probe_count () const
	Report how often curl retained writable interest while the peer held an incomplete control command.
Public Member Functions inherited from proto_fuzzer::MockServerBase
virtual	~MockServerBase ()
	Out-of-line destructor so MockConnection can stay forward-declared in the base header (its complete type is only needed where unique_ptr is instantiated for destruction).
virtual void	Install (CURL *easy)
	Install the common OPENSOCKETFUNCTION / OPENSOCKETDATA / SOCKOPTFUNCTION callbacks on 'easy'.
virtual void	ConfigureRequestData (ScenarioRequestData *request_data)
	Bind protocol-specific work to the request-data callbacks after their per-scenario state has been constructed.
CURLcode	DriveScenario (CURL *easy, const curl::fuzzer::proto::Scenario &scenario)
	Run 'scenario' to completion on 'easy': allocate a multi, attach 'easy', delegate protocol-specific work to RunLoop, consume its completion message, and clean up.
virtual CURLcode	DriveEasyScenario (CURL *easy, const curl::fuzzer::proto::Scenario &scenario, bool use_events=false)
	Run through the public easy entrypoint when a protocol mock can preload all peer work before curl takes control.
virtual ConnectOnlyRunStats	DriveConnectOnlyScenario (CURL *easy, const curl::fuzzer::proto::Scenario &scenario)
	Establish a CONNECT_ONLY transport, then perform bounded direct I/O.
void	SetMultiObserver (MultiObserver observer)
	Register an observer invoked with the live multi handle after 'easy' is attached and before the drive loop starts.
MockConnection *	connection ()

Protected Member Functions
std::unique_ptr< MockConnection >	CreateConnection () override
	Create the default plaintext transport for the SMTP exchange.
void	HandleLine (std::string_view line) override
	Advance one reply for every complete command.
void	ResetProtocolState () override
	Reset SMTP's recipient bookkeeping for a new drive.
void	QueueShutdownReply () override
	Queue a 221 before the shared transport half-closes.
Protected Member Functions inherited from proto_fuzzer::PingpongMockServer
	PingpongMockServer (MultiDrivePolicy drive_policy=MultiDrivePolicy::kPerform)
	Construct the shared transport state without a borrowed protobuf or open socketpair.
void	BeginMarkerBody (std::string_view terminator)
	Enter marker-terminated body mode.
void	BeginLiteralBody (std::size_t length)
	Enter length-announced literal body mode.
void	BeginExactBody (std::size_t length)
	Enter exact-length body mode.
void	BeginOpaqueDrain ()
	Enter an opaque drain after a transport upgrade.
virtual void	HandleBodyComplete ()
	Called after a body phase reached its terminator and the parser returned to command mode.
curl_socket_t	HandleOpenSocket (curlsocktype purpose=CURLSOCKTYPE_IPCXN, struct curl_sockaddr *address=nullptr) override
	Create the single control socketpair and queue the server greeting.
void	RunLoop (CURLM *multi, CURL *easy, const curl::fuzzer::proto::Scenario &scenario) override
	Alternate curl transitions with immediate peer service until the transfer completes or deterministic idle/operation caps win.
void	HandleDetachedMulti (CurlMultiPtr multi) override
	Give curl's graceful shutdown one last chance to emit its teardown command while the peer still owns its read half, then release the multi as the base class would.
void	ObserveIncomingData (const unsigned char *data, std::size_t size) override
	Append decoded application bytes to the pending parser buffer.
const curl::fuzzer::proto::Scenario *	scenario () const
	Borrowed scenario for the synchronous drive, or nullptr outside RunLoop().
const std::string *	NextControlReply ()
	Return the next command-aligned response within the shared response-count budget.
bool	WriteControlBytes (std::string_view bytes)
	Keep failed peer writes local to the mock.
bool	WriteNextReply ()
	Consume the next scripted reply.
void	ShutdownControlWrite ()
	Half-close the server-to-client direction while retaining the read half.
Protected Member Functions inherited from proto_fuzzer::MockServerBase
	MockServerBase (MultiDrivePolicy drive_policy=MultiDrivePolicy::kPerform)
	Construct an empty base instance with a fixed multi-drive policy.
virtual SocketSetupDisposition	GetSocketSetupDisposition (curl_socket_t curlfd, curlsocktype purpose) const
	Describe the socket returned by HandleOpenSocket without issuing native descriptor queries.
MultiSocketDriver *	multi_socket_driver ()
	Expose the callback state installed for the current socket-action drive.
std::size_t	additional_handle_cleanup_count () const
void	ResumeResponseIfRequested (CURL *easy)
	Resume receive-side callback output at one bounded drive boundary when the dedicated API plan requested it.
void	ApplyPendingBackpressure ()
	Apply the BackpressureConfig cached by DriveScenario to the new connection_.

Additional Inherited Members
Public Types inherited from proto_fuzzer::MockServerBase
using	MultiObserver = std::function<void(CURLM*)>
	Callback type used to publish the driving multi handle to observers.
Static Protected Member Functions inherited from proto_fuzzer::PingpongMockServer
static std::string_view	FirstToken (std::string_view line)
	Remove optional leading horizontal whitespace and return the first token without allocating.
static std::string_view	SecondToken (std::string_view line)
	Skip the first token and return the second whitespace-delimited token without allocating.
static bool	TokenEquals (std::string_view token, std::string_view expected_uppercase)
	Fold only ASCII lowercase command letters.
Static Protected Member Functions inherited from proto_fuzzer::MockServerBase
static int	WaitOnMultiFdset (CURLM *multi, CURLMcode *rc)
	Wait on curl's fdset with a short timeout.
static void	ProbeMultiPollset (CURLM *multi)
	Ask curl to construct and inspect its connection-filter pollset without waiting.
static bool	MultiPollsetWantsWrite (CURLM *multi, curl_socket_t socket)
	Inspect one socket's current writable interest through curl's public multi fdset API.
static bool	UsesTimedDrive (const curl::fuzzer::proto::Scenario &scenario)
	Treat a non-default BackpressureConfig as an explicit request for the slower, timed drive policy.
Protected Attributes inherited from proto_fuzzer::MockServerBase
std::unique_ptr< MockConnection >	connection_
	The per-scenario MockConnection, lazily created by HandleOpenSocket().
int	pending_recv_buf_bytes_
	Cached SO_RCVBUF/SO_SNDBUF setting in bytes.
std::size_t	pending_drain_limit_
	Cached per-call DrainIncoming byte budget.
MultiSocketDriver *	multi_socket_driver_
	Non-owning pointer into DriveScenario's stack.
std::size_t	additional_handle_cleanup_count_
	Number of application-created handles, excluding the caller's parent, successfully removed from the current multi and cleaned up.
bool	resume_response_
	True only for an API-plan multi drive with its one-shot write callback.
MultiObserver	multi_observer_
	Observer receiving the live multi handle at the start of a drive.
Static Protected Attributes inherited from proto_fuzzer::MockServerBase
static constexpr int	kMaxDriveIterations = 512
	Hard operation budget for one scenario.
static constexpr int	kMaxIdleIterations = 8
	Consecutive no-progress budget for ordinary scenarios.
static constexpr int	kMaxTimedIdleIterations = 256
	Explicit backpressure scenarios get a larger idle budget and may use the short timed wait above.

Detailed Description

Services curl's single-connection, line-based SMTP exchange.

SMTP needs neither a data channel nor a second script per socket: curl sends one command at a time and waits for the matching response. This peer therefore treats Scenario.connection as a client-line-aligned reply script. initial_response is the 220 greeting; each on_readable entry is the reply to the next command or SASL continuation (EHLO/HELO, AUTH, MAIL FROM, RCPT TO, DATA, and finally the reply after the message body).

The one exception to the command/reply rhythm is the message body. After a 354 reply to DATA, curl writes the bounded upload script followed by the SMTP end-of-body marker. Those bytes arrive on the same control socket and are not commands, so the shared pingpong transport drains them until it observes "\r\n.\r\n". The post-body 250 is queued at DATA-acceptance time because curl's blocking smtp_done() wait cannot be serviced by the outer loop.

Subclasses replace the transport through CreateConnection(). The implicit- TLS SMTPS peer uses that hook to wrap the identical command exchange in a verified OpenSSL connection; incoming bytes are observed after transport decoding so the state machine does not depend on the carrier.

Definition at line 43 of file smtp_mock_server.h.

Constructor & Destructor Documentation

SmtpMockServer()

proto_fuzzer::SmtpMockServer::SmtpMockServer ( curl::fuzzer::proto::SmtpProbeMode mode = curl::fuzzer::proto::SMTP_PROBE_DEFAULT )

explicit

Begin without a borrowed protobuf or open socketpair.

RunLoop borrows a Scenario only for the synchronous DriveScenario call in which socket callbacks can run.

Parameters

mode	Closed SMTP transport probe selected by target policy.

Definition at line 28 of file smtp_mock_server.cc.

~SmtpMockServer()

proto_fuzzer::SmtpMockServer::~SmtpMockServer ( )

overridedefault

Release the server-owned socketpair half after curl has returned its client descriptor.

The out-of-line destructor keeps MockConnection's complete type local to this translation unit.

Member Function Documentation

ConfigureClient()

void proto_fuzzer::SmtpMockServer::ConfigureClient

(

CURL *

easy

)

const

Apply only closed, harness-owned client controls.

The ordinary scenario option list has already run when the production runner calls this hook.

Parameters

easy	Easy handle configured for the SMTP transfer.

Definition at line 55 of file smtp_mock_server.cc.

CreateConnection()

std::unique_ptr< MockConnection > proto_fuzzer::SmtpMockServer::CreateConnection ( )

overrideprotectedvirtual

Create the default plaintext transport for the SMTP exchange.

The SMTPS subclass overrides this factory while retaining the command/reply parser.

Returns

A new socketpair-backed connection.

Reimplemented from proto_fuzzer::PingpongMockServer.

Reimplemented in proto_fuzzer::SmtpsMockServer.

Definition at line 80 of file smtp_mock_server.cc.

HandleLine()

void proto_fuzzer::SmtpMockServer::HandleLine ( std::string_view command )

overrideprotectedvirtual

Advance one reply for every complete command.

A successful DATA reply switches the parser into body-draining mode. The reply that follows DATA is queued immediately: curl's smtp_done() runs a blocking POSTDATA wait inside curl_multi_perform, so the outer peer service loop cannot run after the body has been written. Pre-queuing it, as the FTP peer does for its final transfer reply, keeps that wait deterministic without changing the order curl observes (354 first, then the post-body response).

Parameters

command

One newline-terminated command from curl.

Implements proto_fuzzer::PingpongMockServer.

Definition at line 163 of file smtp_mock_server.cc.

QueueShutdownReply()

void proto_fuzzer::SmtpMockServer::QueueShutdownReply ( )

overrideprotectedvirtual

Queue a 221 before the shared transport half-closes.

SMTP's blocking QUIT read has a one-second timeout when no reply is available, so even an unfinished transfer gets a liveness reply; any real scripted response already consumed by curl still determines the transfer result.

Reimplemented from proto_fuzzer::PingpongMockServer.

Definition at line 234 of file smtp_mock_server.cc.

ResetProtocolState()

void proto_fuzzer::SmtpMockServer::ResetProtocolState ( )

overrideprotectedvirtual

Reset SMTP's recipient bookkeeping for a new drive.

The shared base has already cleared the transport, reply cursor, transcript, upload capture, and any in-flight body phase.

Reimplemented from proto_fuzzer::PingpongMockServer.

Definition at line 85 of file smtp_mock_server.cc.

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The documentation for this class was generated from the following files:

• proto_fuzzer/smtp_mock_server.h
• proto_fuzzer/smtp_mock_server.cc