Orchestrates a bounded sequence of mock HTTP exchanges: installs socket callbacks on an easy handle, assigns a response script to each new socket, and feeds queued chunks as libcurl reads them. More...

#include <mock_server.h>

Inheritance diagram for proto_fuzzer::MockServer:

Public Member Functions
	MockServer (MultiDrivePolicy drive_policy=MultiDrivePolicy::kPerform)
	Construct an idle MockServer with no scripted responses or open peers.
	~MockServer () override
	Default destructor; current and previous MockConnections clean up their server-side descriptors only after curl has been removed from the multi.
void	SetScripts (const curl::fuzzer::proto::Scenario &scenario)
	Build the complete borrowed script table before entering curl.
void	SetKeepConnectionsOpen (bool keep_open)
	Keep completed response sockets writable instead of half-closing them.
CURLcode	DriveEasyScenario (CURL *easy, const curl::fuzzer::proto::Scenario &scenario, bool use_events=false) override
	Preload all bounded response bytes from inside OPENSOCKETFUNCTION, where the mock still owns both socketpair ends, and half-close the peer when the preload finishes.
ConnectOnlyRunStats	DriveConnectOnlyScenario (CURL *easy, const curl::fuzzer::proto::Scenario &scenario) override
	Establish only the HTTP transport, then pass bounded application bytes through curl's public direct-I/O wrappers.
bool	DeliverNextChunk ()
	Push the next queued chunk.
bool	has_more_chunks () const
bool	ServiceConnections ()
	Service one deterministic application event-loop turn by draining all available request bytes and releasing at most one response chunk.
std::size_t	opened_connection_count () const
	Report how many peer sockets curl opened during the current script run.
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	ObserveState ()
	Default no-op for peers without protocol-specific observations.
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.
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
virtual std::unique_ptr< MockConnection >	CreateConnection ()
	Construct the transport used for one HTTP exchange.
void	ResetConnections ()
	Release all current and retired socketpairs before resetting transport- specific state.
virtual void	ObserveActiveTransfer (CURL *easy)
	Observe curl while its connection filters are still attached.
virtual bool	SupportsRepeatedPollsetProbe () const
	Ordinary HTTP and compatibility peers retain the historical perform-only loop even if an append-only scenario field is present.
curl_socket_t	HandleOpenSocket (curlsocktype purpose=CURLSOCKTYPE_IPCXN, struct curl_sockaddr *address=nullptr) override
	Called by the OPENSOCKETFUNCTION trampoline in the base class.
void	RunLoop (CURLM multi, CURL easy, const curl::fuzzer::proto::Scenario &scenario) override
	Seed the mock from the scenario, then drive the perform loop until curl is done or a deterministic operation/idle budget is hit.
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 void	HandleDetachedMulti (CurlMultiPtr multi)
	Dispose of or retain the multi after its easy handle has been removed.
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::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

Orchestrates a bounded sequence of mock HTTP exchanges: installs socket callbacks on an easy handle, assigns a response script to each new socket, and feeds queued chunks as libcurl reads them.

HTTP in-process mock peer.

Assigns one bounded response script to each socket curl opens, allowing redirects and authentication retries to progress without permitting an unbounded connection graph. WebSocketMockServer keeps its separate single-socket model.

Definition at line 72 of file mock_server.h.

Constructor & Destructor Documentation

◆ MockServer()

proto_fuzzer::MockServer::MockServer ( MultiDrivePolicy drive_policy = MultiDrivePolicy::kPerform )

explicit

Construct an idle MockServer with no scripted responses or open peers.

DriveScenario() configures it from a Scenario before curl can open a socket; the fixed policy decides whether that scenario's ApiPlan controls the loop.

Parameters

drive_policy Multi interface loop selected for this server.

Definition at line 319 of file mock_server.cc.

Member Function Documentation

◆ CreateConnection()

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

protectedvirtual

Construct the transport used for one HTTP exchange.

HTTPS overrides this factory with a TLS record layer while retaining the same bounded response scripts and redirect lifetimes, without copying the HTTP state machine.

Returns: a new connection, whose ok() result is checked before use.

Reimplemented in proto_fuzzer::GopherMockServer, proto_fuzzer::H2CleartextMockServer, proto_fuzzer::H2OriginMockServer, proto_fuzzer::H2ProxyMockServer, proto_fuzzer::HttpTransportMockServer, proto_fuzzer::ProxyOptionMockServer, proto_fuzzer::ProxyTransportMockServer, and proto_fuzzer::TlsMockServer.

Definition at line 377 of file mock_server.cc.

◆ DeliverNextChunk()

bool proto_fuzzer::MockServer::DeliverNextChunk ( )

Push the next queued chunk.

Called by the drive loop when curl is ready for more data.

Returns: true when a chunk was consumed from the script.

Definition at line 541 of file mock_server.cc.

◆ DriveConnectOnlyScenario()

ConnectOnlyRunStats proto_fuzzer::MockServer::DriveConnectOnlyScenario	(	CURL *	easy,
		const curl::fuzzer::proto::Scenario &	scenario )

overridevirtual

Establish only the HTTP transport, then pass bounded application bytes through curl's public direct-I/O wrappers.

Preloading makes receive readiness deterministic without a helper thread; the socketpair peer stays readable after ShutdownWrite and continues accepting the outgoing probe.

Parameters

easy	Configured easy handle whose transport this mock supplies.
scenario	Source of the bounded response and direct-I/O probe bytes.

Returns: Results and byte counts from connect, send, and receive operations.

Reimplemented from proto_fuzzer::MockServerBase.

Definition at line 496 of file mock_server.cc.

◆ DriveEasyScenario()

CURLcode proto_fuzzer::MockServer::DriveEasyScenario	(	CURL *	easy,
		const curl::fuzzer::proto::Scenario &	scenario,
		bool	use_events = false )

overridevirtual

Preload all bounded response bytes from inside OPENSOCKETFUNCTION, where the mock still owns both socketpair ends, and half-close the peer when the preload finishes.

This avoids a helper thread and prevents curl from waiting for the outer chunk-delivery loop. The total serialized fuzz input is capped by libFuzzer's max_len. If a non-blocking preload fills the local socket, curl observes only the successfully queued prefix and the timeouts below bound the incomplete response. This drive has no iteration budget of its own, so it reasserts those timeouts after scenario setopts and clears the option that can disable them.

Parameters

easy	Configured easy handle whose open-socket callback targets this mock.
scenario	Bounded response script to preload before performing.
use_events	Select curl's debug event-based easy entrypoint.

Returns: Transfer result reported by curl's selected easy entrypoint.

Reimplemented from proto_fuzzer::MockServerBase.

Definition at line 471 of file mock_server.cc.

◆ HandleOpenSocket()

curl_socket_t proto_fuzzer::MockServer::HandleOpenSocket	(	curlsocktype	purpose = CURLSOCKTYPE_IPCXN,
		struct curl_sockaddr *	address = nullptr )

overrideprotectedvirtual

Called by the OPENSOCKETFUNCTION trampoline in the base class.

Creates the MockConnection, writes initial_response into it, and returns the client-side fd to hand to libcurl.

Parameters

purpose	Socket role requested by curl; ordinary stream mocks do not need to distinguish outbound HTTP roles.
address	Intended destination retained by curl; the socketpair is already connected and therefore leaves it untouched.

Returns: the client-side fd to hand to libcurl, or CURL_SOCKET_BAD on failure.

Implements proto_fuzzer::MockServerBase.

Definition at line 404 of file mock_server.cc.

◆ has_more_chunks()

bool proto_fuzzer::MockServer::has_more_chunks ( ) const

Returns: true if at least one on_readable chunk has not yet been sent.

Definition at line 369 of file mock_server.cc.

◆ ObserveActiveTransfer()

void proto_fuzzer::MockServer::ObserveActiveTransfer ( CURL * easy )

protectedvirtual

Observe curl while its connection filters are still attached.

Plain HTTP has no transport-specific state to inspect; layered transports override this instead of querying stale state after the multi has been dismantled.

Parameters

easy	Active easy handle, unused by the plaintext transport.

Reimplemented in proto_fuzzer::DohHttpsRrMockServer, and proto_fuzzer::TlsMockServer.

Definition at line 393 of file mock_server.cc.

◆ opened_connection_count()

std::size_t proto_fuzzer::MockServer::opened_connection_count ( ) const

Report how many peer sockets curl opened during the current script run.

Returns: Number of response scripts assigned to live or retired sockets.

Definition at line 604 of file mock_server.cc.

◆ ResetConnections()

void proto_fuzzer::MockServer::ResetConnections ( )

protected

Release all current and retired socketpairs before resetting transport- specific state.

Derived destructors call this while their borrowed state is still alive. This is separate from SetScripts because a derived class may need a stricter order than C++'s derived-member-before-base teardown.

Definition at line 383 of file mock_server.cc.

◆ RunLoop()

void proto_fuzzer::MockServer::RunLoop	(	CURLM *	multi,
		CURL *	easy,
		const curl::fuzzer::proto::Scenario &	scenario )

overrideprotectedvirtual

Seed the mock from the scenario, then drive the perform loop until curl is done or a deterministic operation/idle budget is hit.

Ordinary scenarios never wait; explicit backpressure scenarios may use short select() waits.

Parameters

multi	caller-owned multi; 'easy' is already added.
easy	the curl easy handle attached to this mock.
scenario	source of the initial_response and on_readable chunks.

Implements proto_fuzzer::MockServerBase.

Reimplemented in proto_fuzzer::ProxyOptionMockServer.

Definition at line 654 of file mock_server.cc.

◆ ServiceConnections()

bool proto_fuzzer::MockServer::ServiceConnections ( )

Service one deterministic application event-loop turn by draining all available request bytes and releasing at most one response chunk.

The shared-multi driver owns the outer loop and calls this directly; ordinary perform and socket-action drives use the same peer servicing. Draining first creates request-side space before a response can provoke another write, and releasing only one chunk preserves the scenario's mutation- controlled parser boundaries.

Returns: true when any request or response byte advanced.

Definition at line 594 of file mock_server.cc.

◆ SetKeepConnectionsOpen()

void proto_fuzzer::MockServer::SetKeepConnectionsOpen ( bool keep_open )

Keep completed response sockets writable instead of half-closing them.

The multi-transfer lane uses this to let a queued easy handle reuse an HTTP/1.1 connection; ordinary protocol drives retain close-on-completion.

Parameters

keep_open Whether the peer should suppress its response-side FIN.

Definition at line 366 of file mock_server.cc.

◆ SetScripts()

void proto_fuzzer::MockServer::SetScripts ( const curl::fuzzer::proto::Scenario & scenario )

Build the complete borrowed script table before entering curl.

The primary Connection always occupies slot zero for backwards compatibility; only three subsequent pointers are retained so protobuf mutations cannot allocate socketpairs or prolong redirects in proportion to repeated-field size. The caller must keep the Scenario alive and unmodified until the synchronous drive finishes. RunScenario provides that lifetime, making borrowing safe while avoiding copies of response bytes before curl requests the corresponding socket or chunk.

Parameters

scenario Source of the primary and bounded follow-on scripts.

Definition at line 340 of file mock_server.cc.

◆ SupportsRepeatedPollsetProbe()

bool proto_fuzzer::MockServer::SupportsRepeatedPollsetProbe ( ) const

protectedvirtual

Ordinary HTTP and compatibility peers retain the historical perform-only loop even if an append-only scenario field is present.

Protocol subclasses opt in only when their peer can service every repeated poll turn.

Returns: False for the generic mock server.

Reimplemented in proto_fuzzer::HttpTransportMockServer, and proto_fuzzer::ProxyTransportMockServer.

Definition at line 646 of file mock_server.cc.

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

proto_fuzzer/mock_server.h
proto_fuzzer/mock_server.cc

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MockServer()

Member Function Documentation

◆ CreateConnection()

◆ DeliverNextChunk()

◆ DriveConnectOnlyScenario()

◆ DriveEasyScenario()

◆ HandleOpenSocket()

◆ has_more_chunks()

◆ ObserveActiveTransfer()

◆ opened_connection_count()

◆ ResetConnections()

◆ RunLoop()

◆ ServiceConnections()

◆ SetKeepConnectionsOpen()

◆ SetScripts()

◆ SupportsRepeatedPollsetProbe()