Remove logging.

Now tracking: issue seems to be reaching TEST4.ASM:D11 with an interrupt that it believes to be software-originating.

Components/6845/CRTC6845.hpp

@@ -96,7 +96,7 @@ public:
 			target = (target & 0xff00) | value;
 		};
 		const auto load_high = [value](uint16_t &target) {
-			constexpr uint8_t mask = RefreshMask >> 8;
+			static constexpr uint8_t mask = RefreshMask >> 8;
 			target = uint16_t((target & 0x00ff) | ((value & mask) << 8));
 		};
 

Components/9918/Implementation/YamahaCommands.hpp

@@ -18,7 +18,7 @@ struct Vector {
 	int v[2]{};
 
 	template <int offset, bool high> void set(const uint8_t value) {
-		constexpr uint8_t mask = high ? (offset ? 0x3 : 0x1) : 0xff;
+		static constexpr uint8_t mask = high ? (offset ? 0x3 : 0x1) : 0xff;
 		static constexpr int shift = high ? 8 : 0;
 		v[offset] = (v[offset] & ~(mask << shift)) | ((value & mask) << shift);
 	}

Machines/PCCompatible/FloppyController.hpp

@@ -217,14 +217,21 @@ public:
 					if(!sector) {
 						status_.set(Intel::i8272::Status1::EndOfCylinder);
 						status_.set(Intel::i8272::Status0::AbnormalTermination);
-					}
 
-					results_.serialise(
-						status_,
-						sector->address.track,
-						sector->address.side,
-						sector->address.sector,
-						sector->size);
+						results_.serialise(
+							status_,
+							0,
+							0,
+							0,
+							0);
+					} else {
+						results_.serialise(
+							status_,
+							sector->address.track,
+							sector->address.side,
+							sector->address.sector,
+							sector->size);
+					}
 
 					drive.status = decoder_.drive_head();
 					drive.raised_interrupt = true;

Machines/PCCompatible/IDE.hpp

@@ -120,7 +120,7 @@ private:
 	uint8_t controller_data_;
 	uint8_t controller_status_;
 
-	[[no_unique_address]] Log::Logger<Log::Source::IDE> log_;
+	mutable Log::Logger<Log::Source::IDE> log_;
 };
 
 }

Machines/PCCompatible/KeyboardController.hpp

@@ -93,8 +93,8 @@ public:
 		return key;
 	}
 
-	auto &keyboard() {
-		return *this;
+	void post_keyboard(const uint8_t value) {
+		post(value);
 	}
 
 	void post(const uint8_t value) {
@@ -126,18 +126,66 @@ private:
 */
 template <Analyser::Static::PCCompatible::Model model>
 class KeyboardController<model, typename std::enable_if_t<is_at(model)>> {
+private:
+	template <int delay>
+	struct ByteQueue {
+	public:
+		void append(const std::initializer_list<uint8_t> values) {
+			if(delay && queue_.empty()) {
+				restart_delay();
+			}
+			// Insert in reverse order, at the start of the vector. All outgoing values
+			// are popped from the back. So inserts are expensive, reads are cheap.
+			queue_.insert(queue_.begin(), std::rbegin(values), std::rend(values));
+		}
+
+		bool empty() const {
+			if(delay && delay_count_) {
+				return true;
+			}
+			return queue_.empty();
+		}
+
+		void restart_delay() {
+			delay_count_ = delay;
+		}
+
+		uint8_t next() {
+			const auto next = queue_.back();
+			queue_.pop_back();
+			restart_delay();
+			return next;
+		}
+
+		bool run_for(const int ticks) {
+			if(!delay_count_) return false;
+			delay_count_ = std::max(delay_count_ - ticks, 0);
+			return !delay_count_ && !queue_.empty();
+		}
+
+	private:
+		std::vector<uint8_t> queue_;
+		int delay_count_ = 0;
+	};
 public:
 	KeyboardController(
 		PICs<model> &pics,
 		Speaker &speaker,
 		const Analyser::Static::PCCompatible::Target::VideoAdaptor adaptor
-	) : pics_(pics), speaker_(speaker), keyboard_(*this) {
+	) : pics_(pics), speaker_(speaker) {
 		if(adaptor == Analyser::Static::PCCompatible::Target::VideoAdaptor::MDA) {
 			switches_ |= 0x40;
 		}
 	}
 
 	void run_for(const Cycles cycles) {
+		const bool output_advanced = output_.run_for(cycles.as<int>());
+		const bool keyboard_advanced = keyboard_.run_for(cycles.as<int>());
+		if(output_advanced || keyboard_advanced) {
+			log_.info().append("Advancing output");
+			check_irqs();
+		}
+
 		instruction_count_ += cycles.as<int>();
 
 		if(!perform_delay_) {
@@ -151,8 +199,9 @@ public:
 		}
 	}
 
-	auto &keyboard() {
-		return keyboard_;
+	void post_keyboard(const uint8_t value) {
+		keyboard_.post(value);
+		check_irqs();
 	}
 
 	void write(const uint16_t port, const uint8_t value) {
@@ -162,7 +211,7 @@ public:
 			break;
 
 			case 0x0060:
-				log_.error().append("Keyboard parameter set to %02x", value);
+				log_.info().append("Keyboard parameter set to %02x", value);
 				phase_ = Phase::Data;
 				input_ = value;
 				has_input_ = true;
@@ -170,6 +219,7 @@ public:
 			break;
 
 			case 0x0061:
+//				log_.info().append("Port 61: %02x", value);
 				// TODO:
 				//	b7: 1 = reset IRQ 0
 				//	b3: enable channel check
@@ -178,12 +228,11 @@ public:
 			break;
 
 			case 0x0064:
-				phase_ = Phase::Command;
+				log_.info().append("Command byte: %02x", value);
 				command_ = Command(value);
 				has_command_ = true;
 				has_input_ = false;
 				perform_delay_ = performance_delay(command_);
-
 				perform_command();
 			break;
 		}
@@ -197,14 +246,12 @@ public:
 
 			case 0x0060: {
 				if(has_output()) {
-					advance_output_queue_pointer(output_read_);
-
-					if(!has_output()) {
-						pics_.pic[0].template apply_edge<1>(false);
-					}
+					last_output_ = next_output();
+					keyboard_.output().restart_delay();
+					check_irqs();
 				}
-				log_.error().append("Read from keyboard controller of %02x", output_queue_[output_read_]);
-				return output_queue_[output_read_];
+				log_.info().append("Read from keyboard controller of %02x", last_output_);
+				return last_output_;
 			}
 
 			case 0x0061:
@@ -220,18 +267,18 @@ public:
 				//	b7 = 1 => parity error on transmission;
 				//	b6 = 1 => receive timeout;
 				// 	b5 = 1 => transmit timeout;
-				//	b4 = 1 => keyboard active;
+				//	b4 = 1 => keyboard enabled via physical key;
 				//	b3 = 1 = data at 0060 is command, 0 = data;
 				//	b2 = 1 = selftest OK; 0 = just powered up or reset;
 				//	b1 = 1 => 'input' buffer full (i.e. don't write 0x60 or 0x64 now — this is input to the controller);
 				//	b0 = 1 => 'output' data is full (i.e. reading from 0x60 now makes sense — output is to PC).
 				const uint8_t status =
-					(enabled_ 					? 0x10 : 0x00) |
+					0x10 |
 					(phase_ == Phase::Command	? 0x08 : 0x00) |
 					(is_tested_					? 0x04 : 0x00) |
 					(has_input_					? 0x02 : 0x00) |
 					(has_output()				? 0x01 : 0x00);
-//				log_.error().append("Reading status: %02x", status);
+				log_.info().append("Reading status: %02x", status);
 				return status;
 			}
 		}
@@ -262,6 +309,11 @@ private:
 		ResetBlockBegin = 0xf0,
 	};
 
+	enum Control: uint8_t {
+		AllowKeyboardInterrupts = 0x01,
+		InhibitKeyboard = 0x10,
+	};
+
 	static constexpr bool requires_parameter(const Command command) {
 		return
 			(command >= 0x60 && command < 0x80) ||
@@ -282,12 +334,13 @@ private:
 
 	void transmit(const uint8_t value) {
 		log_.info().append("Enquing %02x", value);
-		advance_output_queue_pointer(output_write_);
-		output_queue_[output_write_] = value;
-		pics_.pic[0].template apply_edge<1>(true);	// TODO: verify.
+		output_.append({value});
+		check_irqs();
 	}
 
 	void perform_command() {
+		phase_ = Phase::Data;
+
 		// Don't do anything until perform_delay_ is 0 and a command and/or other input is ready.
 		if(perform_delay_ || (!has_input_ && !has_command_)) {
 			return;
@@ -295,43 +348,42 @@ private:
 
 		// No command => input only, which is a direct-to-device communication.
 		if(!has_command_) {
-			if(!enabled_) {
-				log_.info().append("Storing device command for later: %02x", input_);
-				keyboard_command_ = input_;
-				has_input_ = false;
-				return;
-			}
 			log_.info().append("Device command: %02x", input_);
+			control_ &= ~Control::InhibitKeyboard;
 			keyboard_.perform(input_);
 			// TODO: mouse?
 			has_input_ = false;
+
+			check_irqs();
 			return;
 		}
 
 		// There is a command, but stop anyway if it requires a parameter and doesn't yet have one.
 		if(requires_parameter(command_) && !has_input_) {
+			phase_ = Phase::Command;
 			return;
 		}
 
-		log_.info().append("Controller command: %02x", command_).append_if(has_input_, " / %02x", input_);
+		log_.info().append("Performing: %02x", command_).append_if(has_input_, " / %02x", input_);
 
 		// Consume command and parameter, and execute.
 		has_command_ = false;
 		if(requires_parameter(command_)) has_input_ = false;
 
 		if(command_ >= Command::ResetBlockBegin) {
-			log_.error().append("Should reset: %x", command_ & 0x0f);
+			log_.info().append("Should reset: %x", command_ & 0x0f);
 
 			if(!(command_ & 1)) {
 				cpu_control_->reset();
 			}
 		} else switch(command_) {
 			default:
-				log_.info().append("Keyboard command unimplemented", command_);
+				log_.info().append("Unimplemented keyboard controller command: %02x", command_);
 			break;
 
 			case Command::WriteCommandByte:
-				is_tested_ = input_ & 0x4;
+				control_ = input_;
+				check_irqs();
 				// TODO:
 				//	b0: 1 = enable first PS/2 port interrupt;
 				//	b1: 1 = enable second port interrupt;
@@ -349,22 +401,20 @@ private:
 			break;
 			case Command::InterfaceTest:
 				transmit(0);	// i.e. no issues uncovered.
+//				should_log = false;
 			break;
 			case Command::ReadTestInputs:
-				transmit(enabled_ ? 0x01 : 0x00);
+				// b0 is the keyboard clock; ensure it's inhibited when asked but otherwise don't attempt realism.
+				transmit((control_ & Control::InhibitKeyboard) ? 0x00 : 0x01);
 			break;
 
-			case Command::DisableKeyboard:	enabled_ = false;	break;
+			case Command::DisableKeyboard:
+				control_ |= Control::InhibitKeyboard;
+				check_irqs();
+			break;
 			case Command::EnableKeyboard:
-				enabled_ = true;
-
-				// If a keybaord command was enqueued, post it now.
-				if(keyboard_command_.has_value()) {
-					input_ = *keyboard_command_;
-					keyboard_command_ = std::nullopt;
-					has_input_ = true;
-					perform_command();
-				}
+				control_ &= ~Control::InhibitKeyboard;
+				check_irqs();
 			break;
 
 			case Command::SetOutputByte:
@@ -383,6 +433,7 @@ private:
 	PICs<model> &pics_;
 	Speaker &speaker_;
 	CPUControl<model> *cpu_control_ = nullptr;
+	uint8_t control_ = 0;
 
 	// Strongly coupled to specific code in the 5170 BIOS, this provides a grossly-inaccurate
 	// linkage between execution speed (-ish) and DRAM refresh. An unambguous nonsense.
@@ -390,21 +441,13 @@ private:
 
 	uint8_t input_;
 	Command command_;
-	std::optional<uint8_t> keyboard_command_;
+
+	ByteQueue<0> output_;
+	uint8_t last_output_ = 0xff;
 
 	bool has_input_ = false;
 	bool has_command_ = false;
 
-	std::array<uint8_t, 8> output_queue_;
-	void advance_output_queue_pointer(size_t &pointer) {
-		pointer = (pointer + 1) % output_queue_.size();
-	}
-
-	size_t output_read_ = 0, output_write_ = 0;
-	bool has_output() const {
-		return output_read_ != output_write_;
-	}
-
 	//	bit 7	  = 0  keyboard inhibited
 	//	bit 6	  = 0  CGA, else MDA
 	//	bit 5	  = 0  manufacturing jumper installed
@@ -415,42 +458,83 @@ private:
 	int perform_delay_ = 0;
 
 	bool is_tested_ = false;
-	bool enabled_ = false;
 
 	enum class Phase {
 		Command,
 		Data,
-	} phase_ = Phase::Command;
+	} phase_ = Phase::Data;
 
 	struct Keyboard {
-		Keyboard(KeyboardController<model> &controller) : controller_(controller) {}
-
-		void post(const uint8_t value) {
-			controller_.post_keyboard({value});
+		// TODO: this is the aped interface for receiving key events from the underlying PC,
+		// hastily added to align with that for the XT controller. A better interface is needed.
+		// Not least because of the nonsense fiction here: delivering XT-converted keypresses
+		// directly from an AT keyboard.
+		void post(const uint8_t key_change) {
+			output_.append({key_change});
 		}
 
 		void perform(const uint8_t command) {
+			// TODO: delay needed here.
+
 			switch(command) {
+				default:
+					log_.error().append("Unimplemented keyboard command: %02x", command);
+				return;
+
+//				case 0xed:
+//					// TODO: use next incoming byte to set LEDs.
+//					output_.append({0xfa});
+//				break;
+
 				case 0xf2:
-					controller_.post_keyboard({0xfa});
+					output_.append({0xfa, 0x83, 0xab});
 				break;
 
 				case 0xff:
-					controller_.post_keyboard({0xfa, 0xaa});
+					output_.append({0xfa, 0xaa});
+//					should_log = true;
 				break;
 			}
 		}
 
+		auto &output() {
+			return output_;
+		}
+
+		const auto &output() const {
+			return output_;
+		}
+
+		bool run_for(const int instructions) {
+			return output_.run_for(instructions);
+		}
+
 	private:
-		KeyboardController<model> &controller_;
+		Log::Logger<Log::Source::Keyboard> log_;
+		ByteQueue<50> output_;
 	} keyboard_;
 
-	friend Keyboard;
-	void post_keyboard(const std::initializer_list<uint8_t> values) {
-		if(!enabled_) return;
-		for(const auto value : values) {
-			transmit(value);
+	bool has_output() const {
+		return !output_.empty();
+	}
+
+	uint8_t next_output() {
+		if(!output_.empty()) {
+			return output_.next();
 		}
+
+		// Should be unreachable.
+		return 0xff;
+	}
+
+	void check_irqs() {
+		bool new_irq1 = false;
+		if(output_.empty() && !(control_ & Control::InhibitKeyboard) && !keyboard_.output().empty()) {
+			output_.append({keyboard_.output().next()});
+			new_irq1 = control_ & Control::AllowKeyboardInterrupts;
+		}
+		pics_.pic[0].template apply_edge<1>(new_irq1);
+		log_.info().append("IRQ1: %d", new_irq1);
 	}
 };
 

Machines/PCCompatible/PCCompatible.cpp

@@ -908,7 +908,12 @@ public:
 
 				// Signal interrupt.
 				context_.flow_controller.unhalt();
-				InstructionSet::x86::fault(Exception::interrupt(pics_.pic[0].acknowledge()), context_);
+				const auto interrupt_id = pics_.pic[0].acknowledge();
+				InstructionSet::x86::fault(Exception::interrupt(interrupt_id), context_);
+
+				if(should_log) {
+					log.info().append("Taking interrupt vector %d", interrupt_id);
+				}
 			}
 
 			// Do nothing if currently halted.
@@ -951,24 +956,25 @@ public:
 //		should_log = (decoded_ip_ >= 0x21d0 && decoded_ip_ < 0x221c);
 
 		if(should_log) {
-			const auto next = to_string(decoded_, InstructionSet::x86::Model::i8086);
-			static std::string previous;
-			if(next != previous) {
-				std::cout << std::hex << decoded_ip_ << " " << next;
-
-				if(decoded_.second.operation() == InstructionSet::x86::Operation::INT) {
-					std::cout << " dl:" << std::hex << +context_.registers.dl() << "; ";
-					std::cout << "ah:" << std::hex << +context_.registers.ah() << "; ";
-					std::cout << "ch:" << std::hex << +context_.registers.ch() << "; ";
-					std::cout << "cl:" << std::hex << +context_.registers.cl() << "; ";
-					std::cout << "dh:" << std::hex << +context_.registers.dh() << "; ";
-					std::cout << "es:" << std::hex << +context_.registers.es() << "; ";
-					std::cout << "bx:" << std::hex << +context_.registers.bx();
-				}
-
-				std::cout << std::endl;
-				previous = next;
-			}
+			log.info().append(
+				"%04x %s \t\t[ds:6Bh]:%02x",
+					decoded_ip_,
+					to_string(decoded_, InstructionSet::x86::Model::i80286).c_str(),
+//					context_.registers.bl()
+					context_.memory.template access<uint8_t, InstructionSet::x86::AccessType::PreauthorisedRead>(
+						InstructionSet::x86::Source::DS,
+						uint16_t(0x6b)
+					)
+			).append_if(decoded_.second.operation() == InstructionSet::x86::Operation::INT,
+				" dl:%02x ah:%02x ch:%02x cl:%02x dh:%02x es:%04x bx:%04x",
+					context_.registers.dl(),
+					context_.registers.ah(),
+					context_.registers.ch(),
+					context_.registers.cl(),
+					context_.registers.dh(),
+					context_.registers.es(),
+					context_.registers.bx()
+			);
 		}
 
 		if(decoded_.second.operation() == InstructionSet::x86::Operation::Invalid) {
@@ -1020,7 +1026,7 @@ public:
 	}
 
 	void set_key_state(const uint16_t key, const bool is_pressed) final {
-		keyboard_.keyboard().post(uint8_t(key | (is_pressed ? 0x00 : 0x80)));
+		keyboard_.post_keyboard(uint8_t(key | (is_pressed ? 0x00 : 0x80)));
 	}
 
 	// MARK: - Activity::Source.

Machines/PCCompatible/PIC.hpp

@@ -9,11 +9,13 @@
 #pragma once
 
 #include "Analyser/Static/PCCompatible/Target.hpp"
+#include "Outputs/Log.hpp"
 
 namespace PCCompatible {
 
 // Cf. https://helppc.netcore2k.net/hardware/pic
 class PIC {
+	using Log = Log::Logger<Log::Source::PIC>;
 public:
 	template <int address>
 	void write(const uint8_t value) {
@@ -42,6 +44,7 @@ public:
 				}
 			} else {
 				mask_ = value;
+				Log::info().append("Mask set to %02x; requests now %02x", mask_, requests_);
 			}
 		} else {
 			if(value & 0x10) {
@@ -59,6 +62,8 @@ public:
 				single_pic_ = value & 2;
 				four_byte_vectors_ = value & 4;
 				level_triggered_ = value & 8;
+
+				Log::info().append("Level triggered: %d", level_triggered_);
 			} else if(value & 0x08) {
 				//
 				// Operation Control Word 3.
@@ -78,7 +83,7 @@ public:
 				// b2, b1, b0:	interrupt level to acknowledge.
 				switch(value >> 5) {
 					default:
-						printf("PIC: TODO EOI type %d\n", value >> 5);
+						Log::error().append("PIC: TODO EOI type %d\n", value >> 5);
 						[[fallthrough]];
 					case 0b010:	// No-op.
 					break;
@@ -109,21 +114,26 @@ public:
 		if(address) {
 			return mask_;
 		}
-		return 0;
+
+		Log::error().append("Reading address 0");
+		return requests_;
 	}
 
 	template <int input>
 	void apply_edge(const bool final_level) {
-		constexpr uint8_t input_mask = 1 << input;
+		static constexpr uint8_t input_mask = 1 << input;
+
+		const auto old_levels = levels_;
+		const uint8_t new_bit = final_level ? input_mask : 0;
+		levels_ = (levels_ & ~input_mask) | new_bit;
 
-		// Guess: level triggered means the request can be forwarded only so long as the
-		// relevant input is actually high. Whereas edge triggered implies capturing state.
 		if(level_triggered_) {
-			requests_ &= ~input_mask;
-		}
-		if(final_level) {
-			requests_ |= input_mask;
+			requests_ = levels_;
+		} else {
+			requests_ |= (levels_ ^ old_levels) & new_bit;
 		}
+
+		Log::info().append("%d to %d => requests now %02x", input, final_level, requests_);
 	}
 
 	bool pending() const {
@@ -143,6 +153,7 @@ public:
 			eoi_target_ = id;
 			awaiting_eoi_ = !auto_eoi_;
 			requests_ &= ~in_service_;
+			Log::info().append("Implicitly acknowledging: %d; requests now: %02x", id, requests_);
 			return uint8_t(vector_base_ + id);
 		}
 
@@ -163,6 +174,7 @@ private:
 
 	uint8_t requests_ = 0;
 	uint8_t in_service_ = 0;
+	uint8_t levels_ = 0;
 
 	struct ConfgurationState {
 		int word;

OSBindings/Mac/Clock Signal.xcodeproj/xcshareddata/xcschemes/Clock Signal.xcscheme

@@ -62,7 +62,7 @@
       </Testables>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Release"
+      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       enableASanStackUseAfterReturn = "YES"

Outputs/Log.hpp

@@ -56,6 +56,8 @@ enum class Source {
 	OpenGL,
 	PCCompatible,
 	PCPOST,
+	PIC,
+	PIT,
 	Plus4,
 	PCMTrack,
 	SCC,
@@ -96,19 +98,20 @@ constexpr EnabledLevel enabled_level(const Source source) {
 		case Source::SCC:
 		case Source::SCSI:
 		case Source::I2C:
+//		case Source::PCPOST:
 			return EnabledLevel::None;
 
 		case Source::Floppy:
+//		case Source::Keyboard:
 			return EnabledLevel::Errors;
 	}
 }
 
 constexpr const char *prefix(const Source source) {
 	switch(source) {
-		default: return nullptr;
-
 		case Source::ADBDevice:					return "ADB device";
 		case Source::ADBGLU:					return "ADB GLU";
+		case Source::Amiga:						return "Amiga";
 		case Source::AmigaBlitter:				return "Blitter";
 		case Source::AmigaChipset:				return "Chipset";
 		case Source::AmigaCopper:				return "Copper";
@@ -143,31 +146,80 @@ constexpr const char *prefix(const Source source) {
 		case Source::Plus4:						return "Plus4";
 		case Source::PCCompatible:				return "PC";
 		case Source::PCPOST:					return "POST";
+		case Source::PIC:						return "PIC";
+		case Source::PIT:						return "PIT";
 		case Source::PCMTrack:					return "PCM Track";
 		case Source::SCSI:						return "SCSI";
 		case Source::SCC:						return "SCC";
 		case Source::SZX:						return "SZX";
 		case Source::TapeUEF:					return "UEF";
+		case Source::TMS9918:					return "TMS9918";
 		case Source::TZX:						return "TZX";
 		case Source::Vic20:						return "Vic20";
 		case Source::WDFDC:						return "WD FDC";
 	}
+
+	return nullptr;
 }
 
 template <Source source, bool enabled>
 struct LogLine;
 
+struct RepeatAccumulator {
+	std::string last;
+	Source source;
+
+	size_t count = 0;
+	FILE *stream;
+};
+
+struct AccumulatingLog {
+	inline static thread_local RepeatAccumulator accumulator_;
+};
+
 template <Source source>
-struct LogLine<source, true> {
+struct LogLine<source, true>: private AccumulatingLog {
 public:
-	explicit LogLine(FILE *const stream) noexcept : stream_(stream) {
-		static constexpr auto source_prefix = prefix(source);
-		if(!source_prefix) return;
-		append("[%s] ", source_prefix);
-	}
+	explicit LogLine(FILE *const stream) noexcept :
+		stream_(stream) {}
 
 	~LogLine() {
-		fprintf(stream_, "%s\n", output_.c_str());
+		if(output_ == accumulator_.last && source == accumulator_.source && stream_ == accumulator_.stream) {
+			++accumulator_.count;
+			return;
+		}
+
+		if(!accumulator_.last.empty()) {
+			const char *const unadorned_prefix = prefix(accumulator_.source);
+			std::string prefix;
+			if(unadorned_prefix) {
+				prefix = "[";
+				prefix += unadorned_prefix;
+				prefix += "] ";
+			}
+
+			if(accumulator_.count > 1) {
+				fprintf(
+					accumulator_.stream,
+					"%s%s [* %zu]\n",
+						prefix.c_str(),
+						accumulator_.last.c_str(),
+						accumulator_.count
+				);
+			} else {
+				fprintf(
+					accumulator_.stream,
+					"%s%s\n",
+						prefix.c_str(),
+						accumulator_.last.c_str()
+				);
+			}
+		}
+
+		accumulator_.count = 1;
+		accumulator_.last = output_;
+		accumulator_.source = source;
+		accumulator_.stream = stream_;
 	}
 
 	template <size_t size, typename... Args>
@@ -190,8 +242,8 @@ public:
 	}
 
 private:
-	std::string output_;
 	FILE *stream_;
+	std::string output_;
 };
 
 template <Source source>