More work on object model

Added facility to acquire a read lock around access to an array
Partially implemented Heaters and Sensors in the model

13 files changed, 157 insertions, 34 deletions

diff --git a/src/GCodes/GCodes2.cpp b/src/GCodes/GCodes2.cpp
index 7b8623ba..df1ec9df 100644
--- a/src/GCodes/GCodes2.cpp
+++ b/src/GCodes/GCodes2.cpp
@@ -115,6 +115,7 @@ bool GCodes::HandleGcode(GCodeBuffer& gb, const StringRef& reply)
 	const int code = gb.GetCommandNumber();
 	if (simulationMode != 0 && code > 4 && code != 10 && code != 11 && code != 20 && code != 21 && (code < 53 || code > 59) && (code < 90 || code > 92))
 	{
+		HandleReply(gb, GCodeResult::ok, "");
 		return true;					// we only simulate some gcodes
 	}
 
@@ -404,6 +405,7 @@ bool GCodes::HandleMcode(GCodeBuffer& gb, const StringRef& reply)
 		&& code != 0 && code != 1 && code != 82 && code != 83 && code != 105 && code != 109 && code != 111 && code != 112 && code != 122
 		&& code != 200 && code != 204 && code != 207 && code != 408 && code != 999)
 	{
+		HandleReply(gb, GCodeResult::ok, "");
 		return true;			// we don't simulate most M codes
 	}
 
diff --git a/src/Heating/Heat.cpp b/src/Heating/Heat.cpp
index 8a25d832..cc214ae2 100644
--- a/src/Heating/Heat.cpp
+++ b/src/Heating/Heat.cpp
@@ -60,13 +60,19 @@ extern "C" [[noreturn]] void SensorsTaskStart(void * pvParameters) noexcept
 // Note: if using GCC version 7.3.1 20180622 and lambda functions are used in this table, you must compile this file with option -std=gnu++17.
 // Otherwise the table will be allocated in RAM instead of flash, which wastes too much RAM.
 
-#if 0	// need to extend object model functions to handle read-locked pointers before we can use this
-static const ObjectModelArrayDescriptor heatersArrayDescriptor =
+const ObjectModelArrayDescriptor Heat::heatersArrayDescriptor =
 {
-	[] (ObjectModel *self) -> size_t { return MaxHeaters; },
-	[] (ObjectModel *self, size_t n) -> void* { return (void *)(((Heat*)self)->FindHeater(n)); }
+	&heatersLock,
+	[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return ((const Heat*)self)->GetNumHeatersToReport(); },
+	[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(((const Heat*)self)->heaters[context.GetIndex(0)]); }
+};
+
+const ObjectModelArrayDescriptor Heat::sensorsArrayDescriptor =
+{
+	&sensorsLock,
+	[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return ((const Heat*)self)->GetNumSensorsToReport(); },
+	[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(((const Heat*)self)->FindSensor(context.GetIndex(0)).Ptr()); }
 };
-#endif
 
 // Macro to build a standard lambda function that includes the necessary type conversions
 #define OBJECT_MODEL_FUNC(...) OBJECT_MODEL_FUNC_BODY(Heat, __VA_ARGS__)
@@ -74,14 +80,14 @@ static const ObjectModelArrayDescriptor heatersArrayDescriptor =
 constexpr ObjectModelTableEntry Heat::objectModelTable[] =
 {
 	// These entries must be in alphabetical order
+	// 0. Heat class
 	{ "ColdExtrudeTemperature", OBJECT_MODEL_FUNC(self->extrusionMinTemp), ObjectModelEntryFlags::none},
 	{ "ColdRetractTemperature", OBJECT_MODEL_FUNC(self->retractionMinTemp), ObjectModelEntryFlags::none},
-#if 0
-	{ "Heaters", OBJECT_MODEL_FUNC_NOSELF(&heatersArrayDescriptor), ObjectModelEntryFlags::none }
-#endif
+	{ "Heaters", OBJECT_MODEL_FUNC_NOSELF(&heatersArrayDescriptor), ObjectModelEntryFlags::none },
+	{ "Sensors", OBJECT_MODEL_FUNC_NOSELF(&sensorsArrayDescriptor), ObjectModelEntryFlags::none },
 };
 
-constexpr uint8_t Heat::objectModelTableDescriptor[] = { 1, 2 };
+constexpr uint8_t Heat::objectModelTableDescriptor[] = { 3, 4, 0, 0 };
 
 DEFINE_GET_OBJECT_MODEL_TABLE(Heat)
 
@@ -254,6 +260,10 @@ ReadLockedPointer<TemperatureSensor> Heat::FindSensor(int sn) const noexcept
 		{
 			return ReadLockedPointer<TemperatureSensor>(locker, sensor);
 		}
+		if ((int)sensor->GetSensorNumber() > sn)
+		{
+			break;
+		}
 	}
 	return ReadLockedPointer<TemperatureSensor>(locker, nullptr);
 }
@@ -1210,15 +1220,34 @@ float Heat::GetSensorTemperature(int sensorNum, TemperatureError& err) const noe
 	return BadErrorTemperature;
 }
 
-// Return the highest used heater number. Used by RepRap.cpp to shorten responses by omitting unused trailing heater numbers. If no heaters are configured, return 0.
-size_t Heat::GetHighestUsedHeaterNumber() const noexcept
+// Return the highest used heater number plus one. Used by RepRap.cpp to shorten responses by omitting unused trailing heater numbers.
+size_t Heat::GetNumHeatersToReport() const noexcept
+{
+	size_t ret = ARRAY_SIZE(heaters);
+	while (ret != 0 && heaters[ret] == nullptr)
+	{
+		--ret;
+	}
+	return ret;
+}
+
+// Return the highest used sensor number plus one
+size_t Heat::GetNumSensorsToReport() const noexcept
 {
-	size_t highestHeater = ARRAY_SIZE(heaters);
-	do
+	ReadLocker lock(sensorsLock);
+
+	const TemperatureSensor *s = sensorsRoot;
+	if (s == nullptr)
 	{
-		--highestHeater;
-	} while (heaters[highestHeater] == nullptr && highestHeater != 0);
-	return highestHeater;
+		return 0;
+	}
+
+	// Find the last sensor in the list
+	while (s->GetNext() != nullptr)
+	{
+		s = s->GetNext();
+	}
+	return s->GetSensorNumber() + 1;
 }
 
 // Get the temperature of a heater
diff --git a/src/Heating/Heat.h b/src/Heating/Heat.h
index 22c011a1..a369d23c 100644
--- a/src/Heating/Heat.h
+++ b/src/Heating/Heat.h
@@ -92,7 +92,8 @@ public:
 	float GetSensorTemperature(int sensorNum, TemperatureError& err) const noexcept; // Result is in degrees Celsius
 
 	float GetHighestTemperatureLimit() const noexcept;					// Get the highest temperature limit of any heater
-	size_t GetHighestUsedHeaterNumber() const noexcept;
+	size_t GetNumHeatersToReport() const noexcept;
+	size_t GetNumSensorsToReport() const noexcept;
 
 	void Diagnostics(MessageType mtype) noexcept;						// Output useful information
 
@@ -145,6 +146,11 @@ public:
 protected:
 	DECLARE_OBJECT_MODEL
 
+#if SUPPORT_OBJECT_MODEL
+	static const ObjectModelArrayDescriptor heatersArrayDescriptor;
+	static const ObjectModelArrayDescriptor sensorsArrayDescriptor;
+#endif
+
 private:
 	Heat(const Heat&) = delete;									// Private copy constructor to prevent copying
 
diff --git a/src/Heating/Heater.cpp b/src/Heating/Heater.cpp
index 87b7b57c..7dc201bb 100644
--- a/src/Heating/Heater.cpp
+++ b/src/Heating/Heater.cpp
@@ -12,6 +12,30 @@
 #include "HeaterProtection.h"
 #include "Sensors/TemperatureSensor.h"
 
+#if SUPPORT_OBJECT_MODEL
+
+// Object model table and functions
+// Note: if using GCC version 7.3.1 20180622 and lambda functions are used in this table, you must compile this file with option -std=gnu++17.
+// Otherwise the table will be allocated in RAM instead of flash, which wastes too much RAM.
+
+// Macro to build a standard lambda function that includes the necessary type conversions
+#define OBJECT_MODEL_FUNC(...) OBJECT_MODEL_FUNC_BODY(Heater, __VA_ARGS__)
+
+constexpr ObjectModelTableEntry Heater::objectModelTable[] =
+{
+	// Within each group, these entries must be in alphabetical order
+	// 0. Heater members
+	{ "Current",	OBJECT_MODEL_FUNC(self->GetTemperature()), 							ObjectModelEntryFlags::none },
+	{ "Sensor",		OBJECT_MODEL_FUNC((int32_t)self->GetSensorNumber()), 				ObjectModelEntryFlags::none },
+	{ "State",		OBJECT_MODEL_FUNC(self->GetStateName()), 							ObjectModelEntryFlags::none },
+};
+
+constexpr uint8_t Heater::objectModelTableDescriptor[] = { 1, 3 };
+
+DEFINE_GET_OBJECT_MODEL_TABLE(Heater)
+
+#endif
+
 Heater::Heater(unsigned int num) noexcept
 	: heaterNumber(num), sensorNumber(-1), activeTemperature(0.0), standbyTemperature(0.0),
 	  maxTempExcursion(DefaultMaxTempExcursion), maxHeatingFaultTime(DefaultMaxHeatingFaultTime),
@@ -75,6 +99,12 @@ HeaterStatus Heater::GetStatus() const noexcept
 							: HeaterStatus::standby;
 }
 
+const char *Heater::GetStateName() const noexcept
+{
+	static const char * const StateNames[] = { "Off", "Standby", "Active", "Tuning", "Offline" };
+	return StateNames[(uint8_t)GetStatus()];
+}
+
 const char* Heater::GetSensorName() const noexcept
 {
 	const auto sensor = reprap.GetHeat().FindSensor(sensorNumber);
diff --git a/src/Heating/Heater.h b/src/Heating/Heater.h
index f8bbb33d..7a26e441 100644
--- a/src/Heating/Heater.h
+++ b/src/Heating/Heater.h
@@ -11,6 +11,7 @@
 #include "RepRapFirmware.h"
 #include "FOPDT.h"
 #include "GCodes/GCodeResult.h"
+#include <ObjectModel/ObjectModel.h>
 
 #if SUPPORT_CAN_EXPANSION
 # include "CanId.h"
@@ -22,7 +23,7 @@ struct CanHeaterReport;
 // Enumeration to describe the status of a heater. Note that the web interface returns the numerical values, so don't change them.
 enum class HeaterStatus { off = 0, standby = 1, active = 2, fault = 3, tuning = 4, offline = 5 };
 
-class Heater
+class Heater INHERIT_OBJECT_MODEL
 {
 public:
 	Heater(unsigned int num) noexcept;
@@ -79,6 +80,8 @@ public:
 	bool CheckGood() const noexcept;
 
 protected:
+	DECLARE_OBJECT_MODEL
+
 	enum class HeaterMode : uint8_t
 	{
 		// The order of these is important because we test "mode > HeatingMode::suspended" to determine whether the heater is active
@@ -114,7 +117,8 @@ protected:
 	FopDt model;
 
 private:
-	bool CheckProtection() const noexcept;					// Check heater protection elements and return true if everything is good
+	bool CheckProtection() const noexcept;			// Check heater protection elements and return true if everything is good
+	const char *GetStateName() const noexcept;
 
 	unsigned int heaterNumber;
 	int sensorNumber;								// the sensor number used by this heater
diff --git a/src/Heating/Sensors/TemperatureSensor.cpp b/src/Heating/Sensors/TemperatureSensor.cpp
index a8d7a2cc..9b82e6be 100644
--- a/src/Heating/Sensors/TemperatureSensor.cpp
+++ b/src/Heating/Sensors/TemperatureSensor.cpp
@@ -24,6 +24,30 @@
 # include "CAN/CanInterface.h"
 #endif
 
+#if SUPPORT_OBJECT_MODEL
+
+// Object model table and functions
+// Note: if using GCC version 7.3.1 20180622 and lambda functions are used in this table, you must compile this file with option -std=gnu++17.
+// Otherwise the table will be allocated in RAM instead of flash, which wastes too much RAM.
+
+// Macro to build a standard lambda function that includes the necessary type conversions
+#define OBJECT_MODEL_FUNC(...) OBJECT_MODEL_FUNC_BODY(TemperatureSensor, __VA_ARGS__)
+
+constexpr ObjectModelTableEntry TemperatureSensor::objectModelTable[] =
+{
+	// Within each group, these entries must be in alphabetical order
+	// 0. TemperatureSensor members
+	{ "LastReading",	OBJECT_MODEL_FUNC(self->lastTemperature), 		ObjectModelEntryFlags::none },
+	{ "Name",			OBJECT_MODEL_FUNC(self->sensorName), 			ObjectModelEntryFlags::none },
+	{ "Type",			OBJECT_MODEL_FUNC(self->sensorType), 			ObjectModelEntryFlags::none },
+};
+
+constexpr uint8_t TemperatureSensor::objectModelTableDescriptor[] = { 1, 3 };
+
+DEFINE_GET_OBJECT_MODEL_TABLE(TemperatureSensor)
+
+#endif
+
 // Constructor
 TemperatureSensor::TemperatureSensor(unsigned int sensorNum, const char *t) noexcept
 	: next(nullptr), sensorNumber(sensorNum), sensorType(t), sensorName(nullptr),
diff --git a/src/Heating/Sensors/TemperatureSensor.h b/src/Heating/Sensors/TemperatureSensor.h
index d4b50a6d..fc522974 100644
--- a/src/Heating/Sensors/TemperatureSensor.h
+++ b/src/Heating/Sensors/TemperatureSensor.h
@@ -5,11 +5,12 @@
 #include "Heating/TemperatureError.h"		// for result codes
 #include "Hardware/IoPorts.h"
 #include "GCodes/GCodeResult.h"
+#include <ObjectModel/ObjectModel.h>
 
 class GCodeBuffer;
 struct CanSensorReport;
 
-class TemperatureSensor
+class TemperatureSensor INHERIT_OBJECT_MODEL
 {
 public:
 	TemperatureSensor(unsigned int sensorNum, const char *type) noexcept;
@@ -80,6 +81,8 @@ public:
 	virtual bool PollInTask() noexcept { return false; };		// Classes implementing this method need to also call Heat::EnsureSensorsTask() after succesful configuration
 
 protected:
+	DECLARE_OBJECT_MODEL
+
 	void SetResult(float t, TemperatureError rslt) noexcept;
 	void SetResult(TemperatureError rslt) noexcept;
 
diff --git a/src/Movement/Move.cpp b/src/Movement/Move.cpp
index c656b29b..3614b08c 100644
--- a/src/Movement/Move.cpp
+++ b/src/Movement/Move.cpp
@@ -56,6 +56,7 @@
 
 static const ObjectModelArrayDescriptor axesArrayDescriptor =
 {
+	nullptr,
 	[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return reprap.GetGCodes().GetVisibleAxes(); },
 	[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(self, 3); }
 };
diff --git a/src/Networking/Network.cpp b/src/Networking/Network.cpp
index f5b1a6a4..dd70d29d 100644
--- a/src/Networking/Network.cpp
+++ b/src/Networking/Network.cpp
@@ -71,6 +71,7 @@ Network::Network(Platform& p) noexcept : platform(p), responders(nullptr), nextR
 
 static const ObjectModelArrayDescriptor interfaceArrayDescriptor =
 {
+	nullptr,
 	[] (const ObjectModel *self, const ObjectExplorationContext& context) noexcept -> size_t { return NumNetworkInterfaces; },
 	[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(((Network*)self)->GetInterface(context.GetIndex(0))); }
 };
diff --git a/src/ObjectModel/ObjectModel.cpp b/src/ObjectModel/ObjectModel.cpp
index 36375ec5..3221a532 100644
--- a/src/ObjectModel/ObjectModel.cpp
+++ b/src/ObjectModel/ObjectModel.cpp
@@ -112,7 +112,11 @@ bool ObjectModel::ReportItemAsJson(OutputBuffer *buf, ObjectExplorationContext&
 			}
 			buf->cat('[');
 			context.AddIndex(index);
-			const bool ret = ReportItemAsJson(buf, context, val.omadVal->GetElement(this, context), endptr + 1);
+			bool ret;
+			{
+				ReadLocker lock(val.omadVal->lockPointer);
+				ret = ReportItemAsJson(buf, context, val.omadVal->GetElement(this, context), endptr + 1);
+			}
 			context.RemoveIndex();
 			buf->cat(']');
 			return ret;
@@ -124,11 +128,15 @@ bool ObjectModel::ReportItemAsJson(OutputBuffer *buf, ObjectExplorationContext&
 		return false;
 
 	case TYPE_OF(const ObjectModel*):
-		if (*filter == '.')
+		if (val.omVal != nullptr)
 		{
-			++filter;
+			if (*filter == '.')
+			{
+				++filter;
+			}
+			return val.omVal->ReportAsJson(buf, context, val.param, filter);
 		}
-		return val.omVal->ReportAsJson(buf, context, val.param, filter);
+		buf->cat("null");
 		break;
 
 	case TYPE_OF(float):
@@ -212,6 +220,8 @@ bool ObjectModel::ReportItemAsJson(OutputBuffer *buf, ObjectExplorationContext&
 // Report an entire array as JSON
 bool ObjectModel::ReportArrayAsJson(OutputBuffer *buf, ObjectExplorationContext& context, const ObjectModelArrayDescriptor *omad, const char *filter) const
 {
+	ReadLocker lock(omad->lockPointer);
+
 	buf->cat('[');
 	bool ret = true;
 	const size_t count = omad->GetNumElements(this, context);
@@ -322,7 +332,7 @@ ExpressionValue ObjectModel::GetObjectValue(const StringParser& sp, const char *
 // Get the value of an object
 ExpressionValue ObjectModel::GetObjectValue(const StringParser& sp, ObjectExplorationContext& context, uint8_t tableNumber, const char *idString) const
 {
-	const ObjectModelTableEntry *e = FindObjectModelTableEntry(tableNumber, idString);
+	const ObjectModelTableEntry *const e = FindObjectModelTableEntry(tableNumber, idString);
 	if (e == nullptr)
 	{
 		throw sp.ConstructParseException("unknown value %s", idString);
@@ -330,7 +340,12 @@ ExpressionValue ObjectModel::GetObjectValue(const StringParser& sp, ObjectExplor
 
 	idString = GetNextElement(idString);
 	ExpressionValue val = e->func(this, context);
-	while (val.type == TYPE_OF(const ObjectModelArrayDescriptor*))
+	return GetObjectValue(sp, context, val, idString);
+}
+
+ExpressionValue ObjectModel::GetObjectValue(const StringParser& sp, ObjectExplorationContext& context, ExpressionValue val, const char *idString) const
+{
+	if (val.type == TYPE_OF(const ObjectModelArrayDescriptor*))
 	{
 		if (*idString != '[')
 		{
@@ -342,15 +357,19 @@ ExpressionValue ObjectModel::GetObjectValue(const StringParser& sp, ObjectExplor
 		{
 			throw sp.ConstructParseException("expected ']'");
 		}
+
+		ReadLocker lock(val.omadVal->lockPointer);
+
 		if (index < 0 || (size_t)index >= val.omadVal->GetNumElements(this, context))
 		{
 			throw sp.ConstructParseException("array index out of bounds");
 		}
 
-		idString = endptr + 1;							// skip past the ']'
+		idString = endptr + 1;								// skip past the ']'
 		context.AddIndex(index);
-		val = val.omadVal->GetElement(this, context);		// fetch the array element
+		val = GetObjectValue(sp, context, val.omadVal->GetElement(this, context), idString);
 		context.RemoveIndex();
+		return val;
 	}
 
 	if (val.type == TYPE_OF(const ObjectModel*))
diff --git a/src/ObjectModel/ObjectModel.h b/src/ObjectModel/ObjectModel.h
index bde3eabd..75d3a723 100644
--- a/src/ObjectModel/ObjectModel.h
+++ b/src/ObjectModel/ObjectModel.h
@@ -133,6 +133,7 @@ private:
 class ObjectModelArrayDescriptor
 {
 public:
+	ReadWriteLock *lockPointer;
 	size_t (*GetNumElements)(const ObjectModel*, const ObjectExplorationContext&) noexcept;
 	ExpressionValue (*GetElement)(const ObjectModel*, ObjectExplorationContext&) noexcept;
 };
@@ -159,9 +160,12 @@ protected:
 	// Report an entire array as JSON
 	bool ReportArrayAsJson(OutputBuffer *buf, ObjectExplorationContext& context, const ObjectModelArrayDescriptor *omad, const char *filter) const THROWS_GCODE_EXCEPTION;
 
-	// Get the value of an object
+	// Get the value of an object via the table
 	ExpressionValue GetObjectValue(const StringParser& sp, ObjectExplorationContext& context, uint8_t tableNumber, const char *idString) const THROWS_GCODE_EXCEPTION;
 
+	// Get the value of an object that we hold
+	ExpressionValue GetObjectValue(const StringParser& sp, ObjectExplorationContext& context, ExpressionValue val, const char *idString) const THROWS_GCODE_EXCEPTION;
+
 	// Get the object model table entry for the current level object in the query
 	const ObjectModelTableEntry *FindObjectModelTableEntry(uint8_t tableNumber, const char *idString) const noexcept;
 
diff --git a/src/RepRap.cpp b/src/RepRap.cpp
index 3539c594..63a74da8 100644
--- a/src/RepRap.cpp
+++ b/src/RepRap.cpp
@@ -1151,8 +1151,8 @@ OutputBuffer *RepRap::GetStatusResponse(uint8_t type, ResponseSource source) noe
 		response->cat("\"current\":");
 		ch = '[';
 		{
-			const size_t highestHeater = heat->GetHighestUsedHeaterNumber();
-			for (size_t heater = 0; heater <= highestHeater; heater++)
+			const size_t numHeaters = heat->GetNumHeatersToReport();
+			for (size_t heater = 0; heater < numHeaters; heater++)
 			{
 				response->catf("%c%.1f", ch, (double)heat->GetHeaterTemperature(heater));
 				ch = ',';
@@ -1162,7 +1162,7 @@ OutputBuffer *RepRap::GetStatusResponse(uint8_t type, ResponseSource source) noe
 			// Current states
 			response->cat(",\"state\":");
 			ch = '[';
-			for (size_t heater = 0; heater <= highestHeater; heater++)
+			for (size_t heater = 0; heater < numHeaters; heater++)
 			{
 				response->catf("%c%d", ch, (int)heat->GetStatus(heater));
 				ch = ',';
@@ -1174,7 +1174,7 @@ OutputBuffer *RepRap::GetStatusResponse(uint8_t type, ResponseSource source) noe
 			{
 				response->cat(",\"names\":");
 				ch = '[';
-				for (size_t heater = 0; heater <= highestHeater; heater++)
+				for (size_t heater = 0; heater < numHeaters; heater++)
 				{
 					response->cat(ch);
 					ch = ',';
diff --git a/src/Version.h b/src/Version.h
index a156cd0b..1bcc9d29 100644
--- a/src/Version.h
+++ b/src/Version.h
@@ -20,7 +20,7 @@
 #endif
 
 #ifndef DATE
-# define DATE "2020-01-07b3"
+# define DATE "2020-01-08b1"
 #endif
 
 #define AUTHORS "reprappro, dc42, chrishamm, t3p3, dnewman, printm3d"