Do not crash if no userdata is passed to the printXXXCb callbacks

Previously, the userdata parameter was used as-is, interpreted as a
Print*. If no userdata was supplied when registering the callback, NULL
is passed, resulting an invalid method lookup and a call to a random
piece of memory (often resulting in a lockup).

By checking for this, forgetting to pass userdata will not lockup, but
also not show any error message (since there is no obvious place to
print it to...). If an invalid pointer is passed, things will still
break, of course.

Author: matthijskooijman

Printers.cpp

@@ -24,12 +24,14 @@ void printHex(Print& p, const uint8_t* buf, size_t len, const __FlashStringHelpe
 
 void printErrorCb(uint8_t code, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->print(F("Error reading API packet. Error code: "));
 	p->println(code);
 }
 
 void printErrorCb(ZBTxStatusResponse& r, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	if (!r.isSuccess()) {
 		p->print(F("Error sending Zigbee packet. Delivery status: "));
 		p->println(r.getDeliveryStatus());
@@ -38,6 +40,7 @@ void printErrorCb(ZBTxStatusResponse& r, uintptr_t data) {
 
 void printErrorCb(TxStatusResponse& r, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	if (!r.isSuccess()) {
 		p->print(F("Error sending packet. Delivery status: "));
 		p->println(r.getStatus());
@@ -46,6 +49,7 @@ void printErrorCb(TxStatusResponse& r, uintptr_t data) {
 
 void printErrorCb(AtCommandResponse& r, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	if (!r.isOk()) {
 		p->print(F("Error sending "));
 		p->write(r.getCommand(), 2);
@@ -56,6 +60,7 @@ void printErrorCb(AtCommandResponse& r, uintptr_t data) {
 
 void printErrorCb(RemoteAtCommandResponse& r, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	if (!r.isOk()) {
 		p->print(F("Error sending remote "));
 		p->write(r.getCommand(), 2);
@@ -90,6 +95,7 @@ void printErrorCb(XBeeResponse& r, uintptr_t data) {
 
 void printRawResponseCb(XBeeResponse& response, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->print("Response: ");
 	// Reconstruct the original packet
 	uint8_t header[] = {START_BYTE, response.getMsbLength(), response.getLsbLength(), response.getApiId()};
@@ -114,6 +120,7 @@ static void printField(Print* p, const __FlashStringHelper *prefix, T data) {
 
 void printResponseCb(ZBTxStatusResponse& status, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println(F("ZBTxStatusResponse:"));
 	printField(p, F("  FrameId: 0x"), status.getFrameId());
 	printField(p, F("  To: 0x"), status.getRemoteAddress());
@@ -123,6 +130,7 @@ void printResponseCb(ZBTxStatusResponse& status, uintptr_t data) {
 
 void printResponseCb(ZBRxResponse& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println(F("ZBRxResponse:"));
 	printField(p, F("  From: 0x"), rx.getRemoteAddress64());
 	printField(p, F("  From: 0x"), rx.getRemoteAddress16());
@@ -137,6 +145,7 @@ void printResponseCb(ZBRxResponse& rx, uintptr_t data) {
 
 void printResponseCb(ZBExplicitRxResponse& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println(F("ZBExplicitRxResponse:"));
 	printField(p, F("  From: 0x"), rx.getRemoteAddress64());
 	printField(p, F("  From: 0x"), rx.getRemoteAddress16());
@@ -155,6 +164,7 @@ void printResponseCb(ZBExplicitRxResponse& rx, uintptr_t data) {
 
 void printResponseCb(ZBRxIoSampleResponse& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println(F("ZBRxIoSampleResponse:"));
 	printField(p, F("  From: 0x"), rx.getRemoteAddress64());
 	printField(p, F("  From: 0x"), rx.getRemoteAddress16());
@@ -181,13 +191,15 @@ void printResponseCb(ZBRxIoSampleResponse& rx, uintptr_t data) {
 
 void printResponseCb(TxStatusResponse& status, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println(F("TxStatusResponse:"));
 	printField(p, F("  FrameId: 0x"), status.getFrameId());
 	printField(p, F("  Status: 0x"), status.getStatus());
 }
 
 void printResponseCb(Rx16Response& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("Rx16Response:");
 	printField(p, F("  From: 0x"), rx.getRemoteAddress16());
 	printField(p, F("  Rssi: 0x"), rx.getRssi());
@@ -202,6 +214,7 @@ void printResponseCb(Rx16Response& rx, uintptr_t data) {
 
 void printResponseCb(Rx64Response& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("Rx64Response:");
 	printField(p, F("  From: 0x"), rx.getRemoteAddress64());
 	printField(p, F("  Rssi: 0x"), rx.getRssi());
@@ -247,6 +260,7 @@ static void printSamples(Print* p, RxIoSampleBaseResponse& rx) {
 
 void printResponseCb(Rx16IoSampleResponse& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("Rx16IoSampleResponse:");
 	printField(p, F("  From: 0x"), rx.getRemoteAddress16());
 	printField(p, F("  Rssi: 0x"), rx.getRssi());
@@ -257,6 +271,7 @@ void printResponseCb(Rx16IoSampleResponse& rx, uintptr_t data) {
 
 void printResponseCb(Rx64IoSampleResponse& rx, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("Rx64IoSampleResponse:");
 	printField(p, F("  From: 0x"), rx.getRemoteAddress64());
 	printField(p, F("  Rssi: 0x"), rx.getRssi());
@@ -267,12 +282,14 @@ void printResponseCb(Rx64IoSampleResponse& rx, uintptr_t data) {
 
 void printResponseCb(ModemStatusResponse& status, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("ModemStatusResponse:");
 	printField(p, F("  Status: 0x"), status.getStatus());
 }
 
 void printResponseCb(AtCommandResponse& at, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("AtCommandResponse:");
 	p->print(F("  Command: "));
 	p->write(at.getCommand(), 2);
@@ -287,6 +304,7 @@ void printResponseCb(AtCommandResponse& at, uintptr_t data) {
 
 void printResponseCb(RemoteAtCommandResponse& at, uintptr_t data) {
 	Print *p = (Print*)data;
+	if (!p) return;
 	p->println("AtRemoteCommandResponse:");
 	printField(p, F("  To: 0x"), at.getRemoteAddress64());
 	printField(p, F("  To: 0x"), at.getRemoteAddress16());