From 95bc5a871b6a3e823cc6ed1c7564e3540456fda0 Mon Sep 17 00:00:00 2001
From: "Robin.Mueller" <robin.mueller.m@gmail.com>
Date: Sat, 6 Jun 2020 13:56:35 +0200
Subject: [PATCH] improved diagnostic messages for linux

---
 devicehandlers/DeviceHandlerBase.cpp |  2 +-
 osal/linux/MessageQueue.cpp          | 32 ++++++++++++++++++++++------
 osal/linux/MessageQueue.h            |  2 +-
 osal/linux/PosixThread.cpp           |  2 +-
 4 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/devicehandlers/DeviceHandlerBase.cpp b/devicehandlers/DeviceHandlerBase.cpp
index c73cf618..965959af 100644
--- a/devicehandlers/DeviceHandlerBase.cpp
+++ b/devicehandlers/DeviceHandlerBase.cpp
@@ -36,7 +36,7 @@ DeviceHandlerBase::DeviceHandlerBase(object_id_t setObjectId,
 		childTransitionDelay(5000),
 		transitionSourceMode(_MODE_POWER_DOWN), transitionSourceSubMode(
 		SUBMODE_NONE), deviceSwitch(setDeviceSwitch) {
-	commandQueue = QueueFactory::instance()->createMessageQueue(1,
+	commandQueue = QueueFactory::instance()->createMessageQueue(cmdQueueSize,
 			CommandMessage::MAX_MESSAGE_SIZE);
 	cookieInfo.state = COOKIE_UNUSED;
 	insertInCommandMap(RAW_COMMAND_ID);
diff --git a/osal/linux/MessageQueue.cpp b/osal/linux/MessageQueue.cpp
index 08a9ab20..493c2aca 100644
--- a/osal/linux/MessageQueue.cpp
+++ b/osal/linux/MessageQueue.cpp
@@ -1,12 +1,14 @@
 #include <framework/serviceinterface/ServiceInterfaceStream.h>
 #include <framework/osal/linux/MessageQueue.h>
+
+#include <fstream>
+
 #include <fcntl.h>           /* For O_* constants */
 #include <sys/stat.h>        /* For mode constants */
 #include <cstring>
 #include <errno.h>
 
 
-
 MessageQueue::MessageQueue(uint32_t messageDepth, size_t maxMessageSize): id(0),
 		lastPartner(0), defaultDestination(NO_QUEUE) {
 	//debug << "MessageQueue::MessageQueue: Creating a queue" << std::endl;
@@ -22,10 +24,11 @@ MessageQueue::MessageQueue(uint32_t messageDepth, size_t maxMessageSize): id(0),
 
 	// Create a nonblocking queue if the name is available (the queue is read
 	// and writable for the owner as well as the group)
-	mqd_t tempId = mq_open(name, O_NONBLOCK | O_RDWR | O_CREAT | O_EXCL,
-	S_IWUSR | S_IREAD | S_IWGRP | S_IRGRP | S_IROTH | S_IWOTH, &attributes);
+	int oflag = O_NONBLOCK | O_RDWR | O_CREAT | O_EXCL;
+	mode_t mode = S_IWUSR | S_IREAD | S_IWGRP | S_IRGRP | S_IROTH | S_IWOTH;
+	mqd_t tempId = mq_open(name, oflag, mode, &attributes);
 	if (tempId == -1) {
-		handleError(&attributes);
+		handleError(&attributes, messageDepth);
 	}
 	else {
 		//Successful mq_open call
@@ -46,10 +49,27 @@ MessageQueue::~MessageQueue() {
 	}
 }
 
-ReturnValue_t MessageQueue::handleError(mq_attr* attributes) {
+ReturnValue_t MessageQueue::handleError(mq_attr* attributes,
+		uint32_t messageDepth) {
 	switch(errno) {
 	case(EINVAL): {
-		sif::error << "MessageQueue::MessageQueue: Invalid Name " << std::endl;
+		sif::error << "MessageQueue::MessageQueue: Invalid Name or attributes"
+				" for message size" << std::endl;
+		size_t defaultMqMaxMsg;
+		if(std::ifstream("/proc/sys/fs/mqueue/msg_max",std::ios::in) >>
+				defaultMqMaxMsg and defaultMqMaxMsg < messageDepth) {
+			// See: https://www.man7.org/linux/man-pages/man3/mq_open.3.html
+			// This happens if the msg_max value is not large enough
+			// It is ignored if the executable is run in privileged mode.
+			// Run the unlockRealtime script or grant the mode manully by using:
+			// sudo setcap 'CAP_SYS_RESOURCE=+ep' <pathToBinary>
+
+			// Permanent solution:
+			// echo msg_max | sudo tee /proc/sys/fs/mqueue/msg_max
+			sif::error << "MessageQueue::MessageQueue: Default MQ size "
+					<< defaultMqMaxMsg << " is too small for requested size "
+					<< messageDepth << std::endl;
+		}
 		break;
 	}
 	case(EEXIST): {
diff --git a/osal/linux/MessageQueue.h b/osal/linux/MessageQueue.h
index debf9cd1..2808d36e 100644
--- a/osal/linux/MessageQueue.h
+++ b/osal/linux/MessageQueue.h
@@ -175,7 +175,7 @@ private:
 
 	static uint16_t queueCounter;
 
-	ReturnValue_t handleError(mq_attr* attributes);
+	ReturnValue_t handleError(mq_attr* attributes, uint32_t messageDepth);
 };
 
 #endif /* MESSAGEQUEUE_H_ */
diff --git a/osal/linux/PosixThread.cpp b/osal/linux/PosixThread.cpp
index 899700f0..e8d624ca 100644
--- a/osal/linux/PosixThread.cpp
+++ b/osal/linux/PosixThread.cpp
@@ -138,7 +138,7 @@ void PosixThread::createTask(void* (*fnc_)(void*), void* arg_) {
 	void* sp;
 	status = posix_memalign(&sp, sysconf(_SC_PAGESIZE), stackSize);
 	if(status != 0){
-		sif::error << "Posix Thread stack init failed with: " <<
+		sif::error << "PosixThread::createTask: Stack init failed with: " <<
 				strerror(status) << std::endl;
 	}