Retry POSIX calls if EINTR value is returned and try a last-ditch brute force enumeration of any ports that aren't properly listed in sysfs on Linux.

src/main/c/Linux/LinuxHelperFunctions.c

@@ -53,6 +53,15 @@ void push_back(struct charPairVector* vector, const char* firstString, const cha
 	strcpy(vector->second[vector->length-1], secondString);
 }
 
+char keyExists(struct charPairVector* vector, const char* key)
+{
+	size_t i;
+	for (i = 0; i < vector->length; ++i)
+		if (strcmp(key, vector->first[i]) == 0)
+			return 1;
+	return 0;
+}
+
 void getFriendlyName(const char* productFile, char* friendlyName)
 {
 	int friendlyNameLength = 0;
@@ -201,6 +210,47 @@ void recursiveSearchForComPorts(charPairVector* comPorts, const char* fullPathTo
 	closedir(directoryIterator);
 }
 
+void lastDitchSearchForComPorts(charPairVector* comPorts)
+{
+	// Open the linux dev directory
+	DIR *directoryIterator = opendir("/dev/");
+	if (!directoryIterator)
+		return;
+
+	// Read all files in the current directory
+	struct dirent *directoryEntry = readdir(directoryIterator);
+	while (directoryEntry)
+	{
+		// See if the file names a potential serial port
+		if ((strlen(directoryEntry->d_name) >= 6) && (directoryEntry->d_name[0] == 't') && (directoryEntry->d_name[1] == 't') && (directoryEntry->d_name[2] == 'y') &&
+				(((directoryEntry->d_name[3] == 'A') && (directoryEntry->d_name[4] == 'M') && (directoryEntry->d_name[5] == 'A')) ||
+						((directoryEntry->d_name[3] == 'A') && (directoryEntry->d_name[4] == 'C') && (directoryEntry->d_name[5] == 'M')) ||
+						((directoryEntry->d_name[3] == 'U') && (directoryEntry->d_name[4] == 'S') && (directoryEntry->d_name[5] == 'B'))))
+		{
+			// Determine system name of port
+			char* systemName = (char*)malloc(256);
+			strcpy(systemName, "/dev/");
+			strcat(systemName, directoryEntry->d_name);
+
+			// Set static friendly name
+			char* friendlyName = (char*)malloc(256);
+			strcpy(friendlyName, "USB-Based Serial Port");
+
+			// Determine if port is already in the list, and add it if not
+			if (!keyExists(comPorts, systemName))
+				push_back(comPorts, systemName, friendlyName);
+
+			// Clean up memory
+			free(systemName);
+			free(friendlyName);
+		}
+		directoryEntry = readdir(directoryIterator);
+	}
+
+	// Close the directory
+	closedir(directoryIterator);
+}
+
 unsigned int getBaudRateCode(int baudRate)
 {
 	switch (baudRate)

src/main/c/Linux/LinuxHelperFunctions.h

@@ -32,9 +32,11 @@ typedef struct charPairVector
 	size_t length;
 } charPairVector;
 void push_back(struct charPairVector* vector, const char* firstString, const char* secondString);
+char keyExists(struct charPairVector* vector, const char* key);
 
 void getDriverName(const char* directoryToSearch, char* friendlyName);
 void recursiveSearchForComPorts(charPairVector* comPorts, const char* fullPathToSearch);
+void lastDitchSearchForComPorts(charPairVector* comPorts);
 void getFriendlyName(const char* productFile, char* friendlyName);
 unsigned int getBaudRateCode(int baudRate);
 void setBaudRate(int portFD, int baudRate);

src/main/c/Linux/SerialPort_Linux.c

@@ -61,6 +61,7 @@ JNIEXPORT jobjectArray JNICALL Java_com_fazecast_jSerialComm_SerialPort_getCommP
 	// Enumerate serial ports on machine
 	charPairVector serialPorts = { (char**)malloc(1), (char**)malloc(1), 0 };
 	recursiveSearchForComPorts(&serialPorts, "/sys/devices/");
+	lastDitchSearchForComPorts(&serialPorts);
 	jobjectArray arrayObject = (*env)->NewObjectArray(env, serialPorts.length, serialCommClass, 0);
 	int i;
 	for (i = 0; i < serialPorts.length; ++i)
@@ -317,7 +318,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_waitForEvent(JNI
 	FD_SET(serialPortFD, &waitingSet);
 
 	// Wait for a serial port event
-	int retVal = select(serialPortFD + 1, &waitingSet, NULL, NULL, &timeout);
+	int retVal;
+	do { retVal = select(serialPortFD + 1, &waitingSet, NULL, NULL, &timeout); } while ((retVal < 0) && (errno == EINTR));
 	if (retVal <= 0)
 		return 0;
 	return (FD_ISSET(serialPortFD, &waitingSet)) ? com_fazecast_jSerialComm_SerialPort_LISTENING_EVENT_DATA_AVAILABLE : 0;
@@ -361,7 +363,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 		// While there are more bytes we are supposed to read
 		while (bytesRemaining > 0)
 		{
-			if ((numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining)) == -1)
+			do { numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining); } while ((numBytesRead < 0) && (errno == EINTR));
+			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
 				close(serialPortFD);
@@ -391,7 +394,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 		// While there are more bytes we are supposed to read and the timeout has not elapsed
 		do
 		{
-			if ((numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining)) == -1)
+			do { numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining); } while ((numBytesRead < 0) && (errno == EINTR));
+			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
 				close(serialPortFD);
@@ -413,7 +417,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 	else		// Semi- or non-blocking specified
 	{
 		// Read from port
-		if ((numBytesRead = read(serialPortFD, readBuffer, bytesToRead)) == -1)
+		do { numBytesRead = read(serialPortFD, readBuffer, bytesToRead); } while ((numBytesRead < 0) && (errno == EINTR));
+		if (numBytesRead == -1)
 		{
 			// Problem reading, close port
 			close(serialPortFD);
@@ -436,10 +441,11 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 	if (serialPortFD <= 0)
 		return -1;
 	jbyte *writeBuffer = (*env)->GetByteArrayElements(env, buffer, 0);
-	int numBytesWritten;
+	int numBytesWritten, result = 0;
 
 	// Write to port
-	if ((numBytesWritten = write(serialPortFD, writeBuffer, bytesToWrite)) == -1)
+	do { numBytesWritten = write(serialPortFD, writeBuffer, bytesToWrite); } while ((numBytesWritten < 0) && (errno == EINTR));
+	if (numBytesWritten == -1)
 	{
 		// Problem writing, close port
 		close(serialPortFD);

src/main/c/OSX/SerialPort_OSX.c

@@ -356,7 +356,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_waitForEvent(JNI
 	FD_SET(serialPortFD, &waitingSet);
 
 	// Wait for a serial port event
-	int retVal = select(serialPortFD + 1, &waitingSet, NULL, NULL, &timeout);
+	int retVal;
+	do { retVal = select(serialPortFD + 1, &waitingSet, NULL, NULL, &timeout); } while ((retVal < 0) && (errno == EINTR));
 	if (retVal <= 0)
 		return 0;
 	return (FD_ISSET(serialPortFD, &waitingSet)) ? com_fazecast_jSerialComm_SerialPort_LISTENING_EVENT_DATA_AVAILABLE : 0;
@@ -401,7 +402,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 		// While there are more bytes we are supposed to read
 		while (bytesRemaining > 0)
 		{
-			if ((numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining)) == -1)
+			do { numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining); } while ((numBytesRead < 0) && (errno == EINTR));
+			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
 				close(serialPortFD);
@@ -431,7 +433,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 		// While there are more bytes we are supposed to read and the timeout has not elapsed
 		do
 		{
-			if ((numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining)) == -1)
+			do { numBytesRead = read(serialPortFD, readBuffer+numBytesReadTotal, bytesRemaining); } while ((numBytesRead < 0) && (errno == EINTR));
+			if (numBytesRead == -1)
 			{
 				// Problem reading, close port
 				close(serialPortFD);
@@ -453,7 +456,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_readBytes(JNIEnv
 	else		// Semi- or non-blocking specified
 	{
 		// Read from port
-		if ((numBytesRead = read(serialPortFD, readBuffer, bytesToRead)) == -1)
+		do { numBytesRead = read(serialPortFD, readBuffer, bytesToRead); } while ((numBytesRead < 0) && (errno == EINTR));
+		if (numBytesRead == -1)
 		{
 			// Problem reading, close port
 			close(serialPortFD);
@@ -479,7 +483,8 @@ JNIEXPORT jint JNICALL Java_com_fazecast_jSerialComm_SerialPort_writeBytes(JNIEn
 	int numBytesWritten;
 
 	// Write to port
-	if ((numBytesWritten = write(serialPortFD, writeBuffer, bytesToWrite)) == -1)
+	do { numBytesWritten = write(serialPortFD, writeBuffer, bytesToWrite); } while ((numBytesWritten < 0) && (errno == EINTR));
+	if (numBytesWritten == -1)
 	{
 		// Problem writing, close port
 		close(serialPortFD);