added internet access detection before version checking is performed

EmotiBitOscilloscope/src/ofApp.cpp

@@ -13,7 +13,6 @@ void ofApp::setup() {
 	ofBackground(255, 255, 255);
 	checkLatestSwVersion();
 	ofSetLogLevel(OF_LOG_NOTICE);
-	writeOfxEmotiBitVersionFile();
 	setTypeTagPlotAttributes();
 	//saveEmotiBitCommSettings();
 	loadEmotiBitCommSettings();
@@ -77,148 +76,219 @@ void ofApp::update() {
 
 void ofApp::checkLatestSwVersion()
 {
-	bool newVersionAvailable = false;
-	// system call to curl
-	std::string latestReleaseUrl = "https://github.com/EmotiBit/ofxEmotiBit/releases/latest";
-	std::string latestReleaseApiRequest = "https://api.github.com/repos/EmotiBit/ofxEmotiBit/releases/latest";
-	std::string command = "curl " + latestReleaseApiRequest;
-	std::string response = "";
+
+	bool isNetworkAvailable = false;
+	// -n specifies number of tries. we are going to try to detect internet connection by sending 1 packet
+	// -w specifies timeout period in mS. We are going to wait for a maximum of 3 seconds for a ping response.
+	// the IP 8.8.8.8 is google's public DNS. We are using ping with a specific IP as that removes undefined wait periods associated with DNS resolution. More details: https://developers.google.com/speed/public-dns
+	std::string command = "ping -n 1 -w 3000 8.8.8.8";
+	std::string pingResponse = "";
 	char buffer[200];
-	bool exceptionOccured = false;
+	ofLogNotice() << "Trying to detect internet access";
 	try
 	{
 #if defined (TARGET_OSX) || defined (TARGET_LINUX)
 		FILE* pipe = popen(command.c_str(), "r"); // returns NULL on fail. refer: https://man7.org/linux/man-pages/man3/popen.3.html#RETURN_VALUE
 #else
 		FILE* pipe = _popen(command.c_str(), "r"); // returns NULL on fail. refer: https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/popen-wpopen?view=msvc-170#return-value
-#endif
+#endif		
 		if (pipe != NULL)
 		{
-			try
+			while (fgets(buffer, sizeof buffer, pipe) != NULL)
 			{
-				while (fgets(buffer, sizeof buffer, pipe) != NULL)
+				pingResponse += buffer;
+			}
+
+#if defined (TARGET_OSX) || defined (TARGET_LINUX)
+			pclose(pipe);
+#else
+			_pclose(pipe);
+#endif
+		}
+		else
+		{
+			ofLogNotice() << "Failed to open pipe. ping failed";
+		}
+	}
+	catch (...)
+	{
+		ofLogError() << "Ping failed";
+	}
+	ofLogNotice() << pingResponse.c_str();
+
+	// A successful ping response contains a sumary of round trip times. We are using that do determine if ping was successful
+	/* A successful ping response
+	------------------------------
+	Pinging 8.8.8.8 with 32 bytes of data:
+	Reply from 8.8.8.8: bytes = 32 time = 18ms TTL = 119
+
+		Ping statistics for 8.8.8.8 :
+		Packets : Sent = 1, Received = 1, Lost = 0 (0 % loss),
+		Approximate round trip times in milli - seconds :
+		Minimum = 18ms, Maximum = 18ms, Average = 18ms
+	*/
+	if (pingResponse.find("Approximate round trip times") != std::string::npos)
+	{
+		// substring found!
+		ofLogNotice() << "internet access detected";
+		isNetworkAvailable = true;
+	}
+	else
+	{
+		// failed
+		ofLogNotice() << "Failed to ping IP";
+	}
+
+	if (isNetworkAvailable)
+	{
+		bool newVersionAvailable = false;
+		// system call to curl
+		std::string latestReleaseUrl = "https://github.com/EmotiBit/ofxEmotiBit/releases/latest";
+		std::string latestReleaseApiRequest = "https://api.github.com/repos/EmotiBit/ofxEmotiBit/releases/latest";
+		// Calling curl with a 3 second timeout. Timeout tested working with curl version v8.0.1. Older versions of curl have shown a "disregard" for the timeout.
+		std::string command = "curl --connect-timeout 3 " + latestReleaseApiRequest;
+		std::string response = "";
+		char buffer[200];
+		bool exceptionOccured = false;
+		try
+		{
+#if defined (TARGET_OSX) || defined (TARGET_LINUX)
+			FILE* pipe = popen(command.c_str(), "r"); // returns NULL on fail. refer: https://man7.org/linux/man-pages/man3/popen.3.html#RETURN_VALUE
+#else
+			FILE* pipe = _popen(command.c_str(), "r"); // returns NULL on fail. refer: https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/popen-wpopen?view=msvc-170#return-value
+#endif
+			if (pipe != NULL)
+			{
+				try
 				{
-					response += buffer;
+					while (fgets(buffer, sizeof buffer, pipe) != NULL)
+					{
+						response += buffer;
+					}
+				}
+				catch (...) {
+					try
+					{
+#if defined (TARGET_OSX) || defined (TARGET_LINUX)
+						pclose(pipe);
+#else
+						_pclose(pipe);
+#endif
+					}
+					catch (...)
+					{
+						ofLogError("Failed to close pipe");
+					}
+					ofLog(OF_LOG_ERROR, "An exception occured while executing curl");
+					exceptionOccured = true;
 				}
-			}
-			catch (...) {
 				try
 				{
-	#if defined (TARGET_OSX) || defined (TARGET_LINUX)
+#if defined (TARGET_OSX) || defined (TARGET_LINUX)
 					pclose(pipe);
-	#else
+#else
 					_pclose(pipe);
-	#endif
+#endif
 				}
 				catch (...)
 				{
 					ofLogError("Failed to close pipe");
 				}
-				ofLog(OF_LOG_ERROR, "An exception occured while executing curl");
-				exceptionOccured = true;
-			}
-			try
-			{
-	#if defined (TARGET_OSX) || defined (TARGET_LINUX)
-				pclose(pipe);
-	#else
-				_pclose(pipe);
-	#endif
 			}
-			catch (...)
+			else
 			{
-				ofLogError("Failed to close pipe");
+				ofLog(OF_LOG_ERROR, "Failed to check for latest version. Failed to open pipe");
+				exceptionOccured = true;
 			}
 		}
-		else
+		catch (...)
 		{
-			ofLog(OF_LOG_ERROR, "Failed to check for latest version. Failed to open pipe");
+			ofLogError("Failed to open pipe");
 			exceptionOccured = true;
 		}
-	}
-	catch (...)
-	{
-		ofLogError("Failed to open pipe");
-		exceptionOccured = true;
-	}
-	try 
-	{
-		if (!exceptionOccured & response != "")
+		try
 		{
-			ofxJSONElement jsonResponse;
-			if (jsonResponse.parse(response))
+			if (!exceptionOccured & response != "")
 			{
-				//ofLog(OF_LOG_NOTICE, jsonResponse.getRawString(true));  // uncomment to print curl output
-				std::string latestAvailableVersion = jsonResponse["tag_name"].asString();
-				ofLogNotice("Latest version") << latestAvailableVersion;
-				int swVerPrefixLoc = latestAvailableVersion.find(SOFTWARE_VERSION_PREFIX);
-				if (swVerPrefixLoc != std::string::npos)
+				ofxJSONElement jsonResponse;
+				if (jsonResponse.parse(response))
 				{
-					latestAvailableVersion.erase(swVerPrefixLoc, 1);  // remove leading version char "v"
-				}
-				// compare with ofxEmotiBitVersion
-				std::vector<std::string> latestVersionSplit = ofSplitString(latestAvailableVersion, ".");
-				std::vector<std::string> currentVersionSplit = ofSplitString(ofxEmotiBitVersion, ".");
-				int versionLength = latestVersionSplit.size() < currentVersionSplit.size() ? latestVersionSplit.size() : currentVersionSplit.size();
-				if (versionLength)
-				{
-					for (int i = 0; i < versionLength; i++)
+					//ofLog(OF_LOG_NOTICE, jsonResponse.getRawString(true));  // uncomment to print curl output
+					std::string latestAvailableVersion = jsonResponse["tag_name"].asString();
+					ofLogNotice("Latest version") << latestAvailableVersion;
+					int swVerPrefixLoc = latestAvailableVersion.find(SOFTWARE_VERSION_PREFIX);
+					if (swVerPrefixLoc != std::string::npos)
 					{
-						int latest = ofToInt(latestVersionSplit.at(i));
-						int current = ofToInt(currentVersionSplit.at(i));
-						if (latest == current)
-						{
-							// need to check minor version
-							continue;
-						}
-						else if (latest < current)
-						{
-							// current version higher than latest available
-							break;
-						}
-						else // latest > current
+						latestAvailableVersion.erase(swVerPrefixLoc, 1);  // remove leading version char "v"
+					}
+					// compare with ofxEmotiBitVersion
+					std::vector<std::string> latestVersionSplit = ofSplitString(latestAvailableVersion, ".");
+					std::vector<std::string> currentVersionSplit = ofSplitString(ofxEmotiBitVersion, ".");
+					int versionLength = latestVersionSplit.size() < currentVersionSplit.size() ? latestVersionSplit.size() : currentVersionSplit.size();
+					if (versionLength)
+					{
+						for (int i = 0; i < versionLength; i++)
 						{
-							// new version available
-							newVersionAvailable = true;
-							break;
+							int latest = ofToInt(latestVersionSplit.at(i));
+							int current = ofToInt(currentVersionSplit.at(i));
+							if (latest == current)
+							{
+								// need to check minor version
+								continue;
+							}
+							else if (latest < current)
+							{
+								// current version higher than latest available
+								break;
+							}
+							else // latest > current
+							{
+								// new version available
+								newVersionAvailable = true;
+								break;
+							}
 						}
 					}
+					else
+					{
+						ofLogError("Failed to parse version string");
+					}
 				}
 				else
 				{
-					ofLogError("Failed to parse version string");
+					ofLog(OF_LOG_ERROR, "unexpected curl response");
 				}
-			}
-			else
-			{
-				ofLog(OF_LOG_ERROR, "unexpected curl response");
-			}
-			// If newer version available, display alert message
-			if (newVersionAvailable)
-			{
-				// create alert dialog box
-				ofSystemAlertDialog("A new version of EmotiBit Software is available!");
-				// open browser to latest version
-				try
+				// If newer version available, display alert message
+				if (newVersionAvailable)
 				{
+					// create alert dialog box
+					ofSystemAlertDialog("A new version of EmotiBit Software is available!");
+					// open browser to latest version
+					try
+					{
 #ifdef TARGET_WIN32
-					std::string command = "start " + latestReleaseUrl;
-					system(command.c_str());
+						std::string command = "start " + latestReleaseUrl;
+						system(command.c_str());
 #else
-					std::string command = "open " + latestReleaseUrl;
-					system(command.c_str());
+						std::string command = "open " + latestReleaseUrl;
+						system(command.c_str());
 #endif
-				}
-				catch (...)
-				{
-					ofLogError("Failed to open browser");
+					}
+					catch (...)
+					{
+						ofLogError("Failed to open browser");
+					}
 				}
 			}
 		}
+		catch (...)
+		{
+			ofLogError("An exception occured while checking latest version of EmotiBit software");
+		}
 	}
-	catch (...)
+	else
 	{
-		ofLogError("An exception occured while checking latest version of EmotiBit software");
+		ofLogNotice() << "Internet access not detected. Skipping version check.";
 	}
 }
 

src/ofxEmotiBitVersion.h

@@ -3,7 +3,7 @@
 #include "ofMain.h"
 
 
-const std::string ofxEmotiBitVersion = "1.8.1";
+const std::string ofxEmotiBitVersion = "1.8.1.fix-swVersionChecker.1";
 
 static const char SOFTWARE_VERSION_PREFIX = 'v';