README.md

@@ -709,6 +709,26 @@ Rebooting currently running image:
 xsc_boot_copy -r
 ```
 
+## Preparation of a fresh rootfs and SD card
+
+This section summarizes important changes between a fresh rootfs and the current
+EIVE implementation
+
+### rootfs
+
+- Mount point `/mnt/sd0` created for SD card 0. Created with `mkdir`
+- Mount point `/mnt/sd1` created for SD card 1. Created with `mkdir`
+- Folder `scripts` in `/home/root` folder.
+- `scripts` folder currently contains `update_main_components.sh` script
+
+### SD Cards
+
+- Folder `bin` for binaries, for example the OBSW
+- Folder `misc` for miscellaneous files
+- Folder `tc` for telecommands
+- Folder `tm` for telemetry
+- Folder `xdi` for XDI components (e.g. for firmware or device tree updates)
+
 # Running the EIVE OBSW on a Raspberry Pi
 
 Special section for running the EIVE OBSW on the Raspberry Pi.

bsp_q7s/boardconfig/q7sConfig.h.in

@@ -4,6 +4,17 @@
 #include <cstdint>
 
 #cmakedefine01 Q7S_SIMPLE_MODE
+
+#define Q7S_SD_NONE                     0
+#define Q7S_SD_COLD_REDUNDANT           1
+#define Q7S_SD_HOT_REDUNDANT            2
+// The OBSW will perform different actions to set up the SD cards depending on the flag set here
+// Set to Q7S_SD_NONE: Don't do anything
+// Set to Q7S_COLD_REDUNDANT: On startup, get the prefered SD card, turn it on and mount it, and 
+//     turn off the second SD card if it is on
+// Set to Q7S_HOT_REDUNDANT: On startup, turn on both SD cards and mount them  
+#define Q7S_SD_CARD_CONFIG              Q7S_SD_COLD_REDUNDANT
+
 #define Q7S_ADD_RTD_DEVICES             0
 
 /* Only one of those 2 should be enabled! */

bsp_q7s/core/CoreController.cpp

@@ -1,4 +1,6 @@
 #include "CoreController.h"
+#include "q7sConfig.h"
+
 #include "../memory/SdCardManager.h"
 
 CoreController::CoreController(object_id_t objectId):
@@ -22,39 +24,125 @@ LocalPoolDataSetBase* CoreController::getDataSetHandle(sid_t sid) {
 }
 
 ReturnValue_t CoreController::initialize() {
-    // Find a way to store this non-volatile outside of SD cards (ProASIC?)
+    return sdCardInit();
-    sd::SdCard preferredSdCard = sd::SdCard::SLOT_0;
-    std::string printoutString;
-    if(preferredSdCard == sd::SdCard::SLOT_0) {
-        printoutString = "0";
-    }
-    else {
-        printoutString = "1";
-    }
-    // Creator or update status file
-    ReturnValue_t result = SdCardManager::instance()->updateSdCardStateFile();
-    if(result != HasReturnvaluesIF::RETURN_OK) {
-        sif::warning << "CoreController::initialize: Updating SD card state file failed"
-                << std::endl;
-    }
-
-    sif::info << "Switching on SD card " << printoutString << ".." << std::endl;
-
-    result = SdCardManager::instance()->switchOnSdCard(preferredSdCard);
-    if(result == SdCardManager::ALREADY_ON) {
-        sif::info << "SD card " << printoutString << " is already on" << std::endl;
-    }
-    else if(result != HasReturnvaluesIF::RETURN_OK) {
-        sif::warning << "CoreController::initialize: Turning SD card on failed"
-                << std::endl;
-    }
-    else {
-        sif::info << "SD card " << printoutString << " was switched on" << std::endl;
-    }
-    return HasReturnvaluesIF::RETURN_OK;
 }
 
 ReturnValue_t CoreController::checkModeCommand(Mode_t mode, Submode_t submode,
         uint32_t *msToReachTheMode) {
     return HasReturnvaluesIF::RETURN_OK;
 }
+
+ReturnValue_t CoreController::sdCardInit() {
+#if Q7S_SD_CARD_CONFIG == Q7S_SD_NONE
+    sif::info << "No SD card initialization will be performed" << std::endl;
+    return HasReturnvaluesIF::RETURN_OK;
+#else
+    SdCardManager* sdcMan = SdCardManager::instance();
+
+    // Create update status file
+    ReturnValue_t result = sdcMan->updateSdCardStateFile();
+    if(result != HasReturnvaluesIF::RETURN_OK) {
+        sif::warning << "CoreController::initialize: Updating SD card state file failed"
+                << std::endl;
+    }
+
+    auto sdStatus = std::pair<sd::SdStatus, sd::SdStatus>(sd::SdStatus::OFF, sd::SdStatus::OFF);
+    result = sdcMan->getSdCardActiveStatus(sdStatus);
+    if(result != HasReturnvaluesIF::RETURN_OK) {
+        sif::warning << "Getting SD card activity status failed" << std::endl;
+    }
+
+    // Use a lambda to avoid duplicate code
+    auto setUpSdCard = [&](sd::SdCard sdCard, sd::SdStatus status, std::string sdString) {
+        std::string mountString;
+        if(sdCard == sd::SdCard::SLOT_0) {
+            mountString = SdCardManager::SD_0_MOUNT_POINT;
+        }
+        else {
+            mountString = SdCardManager::SD_1_MOUNT_POINT;
+        }
+
+        if(status == sd::SdStatus::OFF) {
+            sif::info << "Switching on and mounting SD card " << sdString << " at " <<
+                    mountString << std::endl;
+            return sdcMan->switchOnSdCard(sdCard, true, &sdStatus);
+        }
+        else if(status == sd::SdStatus::ON) {
+            sif::info << "Mounting SD card " << sdString << " at " << mountString << std::endl;
+            return sdcMan->mountSdCard(sdCard);
+        }
+        else {
+            sif::info << "SD card " << sdString << " already on and mounted at " <<
+                    mountString << std::endl;
+            return SdCardManager::ALREADY_MOUNTED;
+        }
+    };
+
+#if Q7S_SD_CARD_CONFIG == Q7S_SD_COLD_REDUNDANT
+    sd::SdCard preferredSdCard = sd::SdCard::SLOT_0;
+    result = sdcMan->getPreferredSdCard(preferredSdCard);
+    if(result != HasReturnvaluesIF::RETURN_OK) {
+        sif::warning << "Could not get preferred SD card information from the scratch buffer"
+                << std::endl;
+    }
+    std::string preferredString;
+    sd::SdStatus preferredStatus = sd::SdStatus::OFF;
+
+    sd::SdStatus otherStatus = sd::SdStatus::OFF;
+    std::string otherString;
+    sd::SdCard otherSdc = sd::SdCard::SLOT_0;
+
+    if(preferredSdCard == sd::SdCard::SLOT_0) {
+        preferredStatus = sdStatus.first;
+        preferredString = "0";
+        otherSdc = sd::SdCard::SLOT_1;
+        otherStatus = sdStatus.second;
+        otherString = "1";
+    }
+    else {
+        preferredString = "1";
+        preferredStatus = sdStatus.second;
+        otherStatus = sdStatus.first;
+        otherSdc = sd::SdCard::SLOT_0;
+        otherString = "0";
+    }
+
+    sif::info << "Cold redundant SD card configuration, preferred SD card " <<
+            preferredString << std::endl;
+
+    result = setUpSdCard(preferredSdCard, preferredStatus, preferredString);
+    if(result != SdCardManager::ALREADY_MOUNTED and result != HasReturnvaluesIF::RETURN_OK) {
+        sif::warning << "Setting up preferred card " << otherString <<
+                " in cold redundant mode failed" << std::endl;
+        // Try other SD card and mark set up operation as failed
+        setUpSdCard(otherSdc, otherStatus, otherString);
+        result = HasReturnvaluesIF::RETURN_FAILED;
+    }
+
+    if(result != HasReturnvaluesIF::RETURN_FAILED and otherStatus != sd::SdStatus::OFF) {
+        sif::info << "Switching off secondary SD card " << otherString << std::endl;
+        // Switch off other SD card in cold redundant mode if setting up preferred one walked
+        // without issues
+        result = sdcMan->switchOffSdCard(otherSdc, otherStatus, &sdStatus);
+        if(result != HasReturnvaluesIF::RETURN_OK and result != SdCardManager::ALREADY_OFF) {
+            sif::warning << "Switching off secondary SD card " << otherString <<
+                    " in cold redundant mode failed" << std::endl;
+        }
+    }
+
+    // Update status file
+    sdcMan->updateSdCardStateFile();
+    return HasReturnvaluesIF::RETURN_OK;
+#elif Q7S_SD_CARD_CONFIG == Q7S_SD_HOT_REDUNDANT
+    sif::info << "Hot redundant SD card configuration" << std::endl;
+
+    setUpSdCard(sd::SdCard::SLOT_0, sdStatus.first, "0");
+    setUpSdCard(sd::SdCard::SLOT_1, sdStatus.second, "1");
+    // Update status file
+    sdcMan->updateSdCardStateFile();
+    return HasReturnvaluesIF::RETURN_OK;
+#endif
+
+#endif /* Q7S_SD_CARD_CONFIG != Q7S_SD_NONE */
+
+}

bsp_q7s/core/CoreController.h

@@ -17,6 +17,8 @@ private:
     LocalPoolDataSetBase* getDataSetHandle(sid_t sid) override;
     ReturnValue_t checkModeCommand(Mode_t mode, Submode_t submode,
                 uint32_t *msToReachTheMode);
+
+    ReturnValue_t sdCardInit();
 };
 
 

bsp_q7s/memory/CMakeLists.txt

@@ -1,6 +1,5 @@
 target_sources(${TARGET_NAME} PRIVATE
     FileSystemHandler.cpp
-    SdCardAccess.cpp
     SdCardManager.cpp
     scratchApi.cpp
 )

bsp_q7s/memory/FileSystemHandler.cpp

@@ -4,9 +4,11 @@
 #include "fsfw/memory/GenericFileSystemMessage.h"
 #include "fsfw/ipc/QueueFactory.h"
 
+#include <filesystem>
+
 FileSystemHandler::FileSystemHandler(object_id_t fileSystemHandler):
         SystemObject(fileSystemHandler) {
-    mq = QueueFactory::instance()->createMessageQueue(50);
+    mq = QueueFactory::instance()->createMessageQueue(FS_MAX_QUEUE_SIZE);
 }
 
 FileSystemHandler::~FileSystemHandler() {
@@ -15,33 +17,86 @@ FileSystemHandler::~FileSystemHandler() {
 
 ReturnValue_t FileSystemHandler::performOperation(uint8_t unsignedChar) {
     while(true) {
-        CommandMessage filemsg;
+        try {
-        ReturnValue_t result = HasReturnvaluesIF::RETURN_OK;
+            fileSystemHandlerLoop();
-        while(true) {
-            result = mq->receiveMessage(&filemsg);
-            if(result == MessageQueueIF::EMPTY) {
-                break;
-            }
-            else if(result != HasReturnvaluesIF::RETURN_FAILED) {
-                sif::warning << "FileSystemHandler::performOperation: Message reception failed!"
-                        << std::endl;
-                break;
-            }
-            Command_t command = filemsg.getCommand();
-            switch(command) {
-            case(GenericFileSystemMessage::CMD_CREATE_DIRECTORY): {
-                break;
-            }
-            case(GenericFileSystemMessage::CMD_CREATE_FILE): {
-                break;
-            }
-            }
         }
+        catch(std::bad_alloc& e) {
+            // Restart OBSW, hints at a memory leak
+            sif::error << "Allocation error in FileSystemHandler::performOperation"
+                    << e.what() << std::endl;
+            // TODO: If we trigger an event, it might not get sent because were restarting
+            // Set up an error file or a special flag in the scratch buffer.
+            // TODO: CoreController: Implement function to restart OBC
+        }
+    }
+}
 
-        // This task will have a low priority and will run permanently in the background
+
-        // so we will just run in a permanent loop here and check file system
+void FileSystemHandler::fileSystemHandlerLoop() {
-        // messages permanently
+    CommandMessage filemsg;
-        TaskFactory::instance()->delayTask(1000);
+    ReturnValue_t result = HasReturnvaluesIF::RETURN_OK;
+    while(true) {
+        if(opCounter % 5 == 0) {
+            fileSystemCheckup();
+        }
+        result = mq->receiveMessage(&filemsg);
+        if(result == MessageQueueIF::EMPTY) {
+            break;
+        }
+        else if(result != HasReturnvaluesIF::RETURN_FAILED) {
+            sif::warning << "FileSystemHandler::performOperation: Message reception failed!"
+                    << std::endl;
+            break;
+        }
+        Command_t command = filemsg.getCommand();
+        switch(command) {
+        case(GenericFileSystemMessage::CMD_CREATE_DIRECTORY): {
+            break;
+        }
+        case(GenericFileSystemMessage::CMD_CREATE_FILE): {
+            break;
+        }
+        }
+        opCounter++;
+    }
+
+    // This task will have a low priority and will run permanently in the background
+    // so we will just run in a permanent loop here and check file system
+    // messages permanently
+    TaskFactory::instance()->delayTask(1000);
+}
+
+void FileSystemHandler::fileSystemCheckup() {
+    SdCardManager::SdStatusPair statusPair;
+    sdcMan->getSdCardActiveStatus(statusPair);
+    sd::SdCard preferredSdCard;
+    sdcMan->getPreferredSdCard(preferredSdCard);
+    if((preferredSdCard == sd::SdCard::SLOT_0) and
+            (statusPair.first == sd::SdStatus::MOUNTED)) {
+        currentMountPrefix = SdCardManager::SD_0_MOUNT_POINT;
+    }
+    if((preferredSdCard == sd::SdCard::SLOT_1) and
+            (statusPair.second == sd::SdStatus::MOUNTED)) {
+        currentMountPrefix = SdCardManager::SD_1_MOUNT_POINT;
+    }
+    else {
+        std::string sdString;
+        if(preferredSdCard == sd::SdCard::SLOT_0) {
+            sdString = "0";
+        }
+        else {
+            sdString = "1";
+        }
+        sif::warning << "FileSystemHandler::performOperation: Inconsistent" <<
+                " state detected. Preferred SD card is " << sdString <<
+                " but does not appear to be mounted. Attempting fix.." << std::endl;
+        // This function will appear to fix the inconsistent state
+        ReturnValue_t result = sdcMan->sanitizeState(&preferredSdCard, &statusPair);
+        if(result != HasReturnvaluesIF::RETURN_OK) {
+            // Oh no.
+            // TODO: Trigger medium severity event
+            sif::error << "Fix failed" << std::endl;
+        }
     }
 }
 
@@ -49,17 +104,81 @@ MessageQueueId_t FileSystemHandler::getCommandQueue() const {
     return mq->getId();
 }
 
+ReturnValue_t FileSystemHandler::initialize() {
+    sdcMan = SdCardManager::instance();
+    sd::SdCard preferredSdCard;
+    ReturnValue_t result = sdcMan->getPreferredSdCard(preferredSdCard);
+    if(result != HasReturnvaluesIF::RETURN_OK) {
+        return result;
+    }
+    if(preferredSdCard == sd::SdCard::SLOT_0) {
+        currentMountPrefix = SdCardManager::SD_0_MOUNT_POINT;
+    }
+    else if(preferredSdCard == sd::SdCard::SLOT_1) {
+        currentMountPrefix = SdCardManager::SD_1_MOUNT_POINT;
+    }
+    return HasReturnvaluesIF::RETURN_OK;
+}
+
 ReturnValue_t FileSystemHandler::appendToFile(const char *repositoryPath, const char *filename,
         const uint8_t *data, size_t size, uint16_t packetNumber, void *args) {
+    // A double slash between repo and filename should not be an issue, so add it in any case
+    std::string fullPath = currentMountPrefix + std::string(repositoryPath) + "/" +
+            std::string(filename);
     return HasReturnvaluesIF::RETURN_OK;
 }
 
 ReturnValue_t FileSystemHandler::createFile(const char *repositoryPath, const char *filename,
         const uint8_t *data, size_t size, void *args) {
+    // A double slash between repo and filename should not be an issue, so add it in any case
+    std::string fullPath = currentMountPrefix + std::string(repositoryPath) + "/" +
+            std::string(filename);
     return HasReturnvaluesIF::RETURN_OK;
 }
 
 ReturnValue_t FileSystemHandler::deleteFile(const char *repositoryPath, const char *filename,
         void *args) {
+    // A double slash between repo and filename should not be an issue, so add it in any case
+    std::string fullPath = currentMountPrefix + std::string(repositoryPath) + "/" +
+            std::string(filename);
+    return HasReturnvaluesIF::RETURN_OK;
+}
+
+ReturnValue_t FileSystemHandler::createDirectory(const char *repositoryPath, void *args) {
+    std::string fullPath = currentMountPrefix + std::string(repositoryPath);
+    if(std::filesystem::exists(fullPath)) {
+        return DIRECTORY_ALREADY_EXISTS;
+    }
+    if(std::filesystem::create_directory(fullPath)) {
+        return HasReturnvaluesIF::RETURN_OK;
+    }
+    sif::warning << "Creating directory " << fullPath << " failed" << std::endl;
+    return GENERIC_FILE_ERROR;
+}
+
+ReturnValue_t FileSystemHandler::removeDirectory(const char *repositoryPath,
+        bool deleteRecurively, void *args) {
+    std::string fullPath = currentMountPrefix + std::string(repositoryPath);
+    if(not std::filesystem::exists(fullPath)) {
+        return DIRECTORY_DOES_NOT_EXIST;
+    }
+    std::error_code err;
+    if(not deleteRecurively) {
+        if(std::filesystem::remove(fullPath, err)) {
+            return HasReturnvaluesIF::RETURN_OK;
+        }
+        else {
+            // Check error code. Most probably denied permissions because folder is not empty
+        }
+    }
+    else {
+        if(std::filesystem::remove_all(fullPath, err)) {
+            return HasReturnvaluesIF::RETURN_OK;
+        }
+        else {
+            // Check error code
+        }
+    }
+
     return HasReturnvaluesIF::RETURN_OK;
 }

bsp_q7s/memory/FileSystemHandler.h

@@ -1,11 +1,16 @@
 #ifndef BSP_Q7S_MEMORY_FILESYSTEMHANDLER_H_
 #define BSP_Q7S_MEMORY_FILESYSTEMHANDLER_H_
 
+#include "SdCardManager.h"
+#include "OBSWConfig.h"
+
 #include "fsfw/ipc/MessageQueueIF.h"
 #include "fsfw/tasks/ExecutableObjectIF.h"
 #include "fsfw/objectmanager/SystemObject.h"
 #include "fsfw/memory/HasFileSystemIF.h"
 
+#include <string>
+
 class FileSystemHandler: public SystemObject,
         public ExecutableObjectIF,
         public HasFileSystemIF {
@@ -15,6 +20,8 @@ public:
 
     ReturnValue_t performOperation(uint8_t) override;
 
+    ReturnValue_t initialize() override;
+
     /**
      * Function to get the MessageQueueId_t of the implementing object
      * @return MessageQueueId_t of the object
@@ -23,6 +30,13 @@ public:
 
 private:
     MessageQueueIF* mq = nullptr;
+    std::string currentMountPrefix = SdCardManager::SD_0_MOUNT_POINT;
+    static constexpr uint32_t FS_MAX_QUEUE_SIZE = config::OBSW_FILESYSTEM_HANDLER_QUEUE_SIZE;
+    SdCardManager* sdcMan = nullptr;
+    uint8_t opCounter = 0;
+
+    void fileSystemHandlerLoop();
+    void fileSystemCheckup();
 
     ReturnValue_t appendToFile(const char* repositoryPath,
             const char* filename, const uint8_t* data, size_t size,
@@ -32,6 +46,9 @@ private:
             size_t size = 0, void* args = nullptr) override;
     ReturnValue_t deleteFile(const char* repositoryPath,
             const char* filename, void* args = nullptr) override;
+    ReturnValue_t createDirectory(const char* repositoryPath, void* args = nullptr) override;
+    ReturnValue_t removeDirectory(const char* repositoryPath,  bool deleteRecurively = false,
+            void* args = nullptr) override;
 };
 
 

bsp_q7s/memory/SdCardAccess.cpp

@@ -1,7 +0,0 @@
-#include "SdCardAccess.h"
-
-#include "fsfw/ipc/MutexGuard.h"
-
-SdCardAccess::SdCardAccess(sd::SdCard sdCard) {
-
-}

bsp_q7s/memory/SdCardAccess.h

@@ -1,13 +0,0 @@
-#ifndef BSP_Q7S_MEMORY_SDCARDACCESS_H_
-#define BSP_Q7S_MEMORY_SDCARDACCESS_H_
-
-#include "definitions.h"
-
-class SdCardAccess {
-public:
-    SdCardAccess(sd::SdCard sdCard);
-private:
-};
-
-
-#endif /* BSP_Q7S_MEMORY_SDCARDACCESS_H_ */

bsp_q7s/memory/SdCardManager.cpp

@@ -1,8 +1,13 @@
 #include "SdCardManager.h"
+#include "scratchApi.h"
+
+#include "linux/utility/utility.h"
+
 #include "fsfw/ipc/MutexFactory.h"
 #include "fsfw/serviceinterface/ServiceInterface.h"
 
 #include <fstream>
+#include <memory>
 #include <filesystem>
 
 SdCardManager* SdCardManager::factoryInstance = nullptr;
@@ -24,35 +29,99 @@ SdCardManager* SdCardManager::instance() {
     return SdCardManager::factoryInstance;
 }
 
-ReturnValue_t SdCardManager::switchOnSdCard(sd::SdCard sdCard) {
+ReturnValue_t SdCardManager::switchOnSdCard(sd::SdCard sdCard, bool doMountSdCard,
-    std::pair<bool, bool> active;
+        SdStatusPair* statusPair) {
-    ReturnValue_t result = sdCardActive(active);
+    ReturnValue_t result = HasReturnvaluesIF::RETURN_OK;
-    if(result != HasReturnvaluesIF::RETURN_OK) {
+    if(statusPair == nullptr) {
+        statusPair = std::make_unique<SdStatusPair>().get();
+        result = getSdCardActiveStatus(*statusPair);
+        if(result != HasReturnvaluesIF::RETURN_OK) {
+            return result;
+        }
+    }
+
+    // Not allowed, this function turns on one SD card
+    if(sdCard == sd::SdCard::BOTH) {
+        sif::warning << "SdCardManager::switchOffSdCard: API does not allow sd::SdStatus::BOTH"
+                << std::endl;
+        return HasReturnvaluesIF::RETURN_FAILED;
+    }
+
+    sd::SdStatus targetStatus;
+    if(sdCard == sd::SdCard::SLOT_0) {
+        targetStatus = statusPair->first;
+    }
+    else if(sdCard == sd::SdCard::SLOT_1) {
+        targetStatus = statusPair->second;
+    }
+
+    auto switchCall = [&]() {
+        if(targetStatus == sd::SdStatus::ON) {
+            if(not doMountSdCard) {
+                return ALREADY_ON;
+            }
+            else {
+                return mountSdCard(sdCard);
+            }
+        }
+        else if(targetStatus == sd::SdStatus::MOUNTED) {
+            return ALREADY_MOUNTED;
+        }
+        else if(targetStatus == sd::SdStatus::OFF) {
+            return setSdCardState(sdCard, true);
+        }
+        else {
+            return HasReturnvaluesIF::RETURN_FAILED;
+        }
+    };
+
+    result = switchCall();
+
+    if(result != HasReturnvaluesIF::RETURN_OK or not doMountSdCard) {
         return result;
     }
-    if((sdCard == sd::SdCard::SLOT_0 and active.first) or
+
-            (sdCard == sd::SdCard::SLOT_1 and active.second)) {
+    return mountSdCard(sdCard);
-        return ALREADY_ON;
-    }
-    return setSdCardState(sdCard, true);
 }
 
-ReturnValue_t SdCardManager::switchOffSdCard(sd::SdCard sdCard) {
+ReturnValue_t SdCardManager::switchOffSdCard(sd::SdCard sdCard, bool doUnmountSdCard,
-    std::pair<bool, bool> active;
+        SdStatusPair* statusPair) {
-    ReturnValue_t result = sdCardActive(active);
+    std::pair<sd::SdStatus, sd::SdStatus> active;
+    ReturnValue_t result = getSdCardActiveStatus(active);
     if(result != HasReturnvaluesIF::RETURN_OK) {
         return result;
     }
-    if((sdCard == sd::SdCard::SLOT_0 and not active.first) or
+    // Not allowed, this function turns off one SD card
-            (sdCard == sd::SdCard::SLOT_1 and not active.second)) {
+    if(sdCard == sd::SdCard::BOTH) {
-        return ALREADY_OFF;
+        sif::warning << "SdCardManager::switchOffSdCard: API does not allow sd::SdStatus::BOTH"
+                << std::endl;
+        return HasReturnvaluesIF::RETURN_FAILED;
     }
+    if(sdCard == sd::SdCard::SLOT_0) {
+        if(active.first == sd::SdStatus::OFF) {
+            return ALREADY_OFF;
+        }
+    }
+    else if(sdCard == sd::SdCard::SLOT_1) {
+        if(active.second == sd::SdStatus::OFF) {
+            return ALREADY_OFF;
+        }
+    }
+
+    if(doUnmountSdCard) {
+        result = unmountSdCard(sdCard);
+        if(result != HasReturnvaluesIF::RETURN_OK) {
+            return result;
+        }
+    }
+
     return setSdCardState(sdCard, false);
 }
 
 ReturnValue_t SdCardManager::setSdCardState(sd::SdCard sdCard, bool on) {
-    std::string sdstring = "";
+    using namespace std;
-    std::string statestring = "";
+    string sdstring = "";
+    string statestring = "";
     if(sdCard == sd::SdCard::SLOT_0) {
         sdstring = "0";
     }
@@ -65,9 +134,9 @@ ReturnValue_t SdCardManager::setSdCardState(sd::SdCard sdCard, bool on) {
     else {
         statestring = "off";
     }
-    std::ostringstream command;
+    ostringstream command;
     command << "q7hw sd set " << sdstring << " " << statestring;
-    int result = std::system(command.str().c_str());
+    int result = system(command.str().c_str());
     if(result == 0) {
         return HasReturnvaluesIF::RETURN_OK;
     }
@@ -76,71 +145,185 @@ ReturnValue_t SdCardManager::setSdCardState(sd::SdCard sdCard, bool on) {
     return SYSTEM_CALL_ERROR;
 }
 
-ReturnValue_t SdCardManager::sdCardActive(std::pair<bool, bool>& active) {
+ReturnValue_t SdCardManager::getSdCardActiveStatus(SdStatusPair& active) {
     using namespace std;
-    if(not filesystem::exists("/tmp/sd_status.txt")) {
+    if(not filesystem::exists(SD_STATE_FILE)) {
         return STATUS_FILE_NEXISTS;
     }
 
     // Now the file should exist in any case. Still check whether it exists.
-    fstream sdStatus("/tmp/sd_status.txt");
+    fstream sdStatus(SD_STATE_FILE);
     if (not sdStatus.good()) {
         return STATUS_FILE_NEXISTS;
     }
     string line;
     uint8_t idx = 0;
-
+    sd::SdCard currentSd = sd::SdCard::SLOT_0;
+    // Process status file line by line
     while (std::getline(sdStatus, line)) {
-        istringstream iss(line);
+        processSdStatusLine(active, line, idx, currentSd);
-        string word;
+    }
-        sd::SdCard currentSd = sd::SdCard::SLOT_0;
+    return HasReturnvaluesIF::RETURN_OK;
-        while(iss >> word) {
+}
+
+ReturnValue_t SdCardManager::mountSdCard(sd::SdCard sdCard) {
+    using namespace std;
+    if(sdCard == sd::SdCard::BOTH) {
+        sif::warning << "SdCardManager::mountSdCard: API does not allow sd::SdStatus::BOTH"
+                << std::endl;
+        return HasReturnvaluesIF::RETURN_FAILED;
+    }
+    string mountDev;
+    string mountPoint;
+    if(sdCard == sd::SdCard::SLOT_0) {
+        mountDev = SD_0_DEV_NAME;
+        mountPoint = SD_0_MOUNT_POINT;
+    }
+    else if(sdCard == sd::SdCard::SLOT_1) {
+        mountDev = SD_1_DEV_NAME;
+        mountPoint = SD_1_MOUNT_POINT;
+    }
+    if(not filesystem::exists(mountDev)) {
+        sif::warning << "SdCardManager::mountSdCard: Device file does not exists. Make sure to"
+                " turn on the SD card" << std::endl;
+        return MOUNT_ERROR;
+    }
+
+    string sdMountCommand = "mount " + mountDev + " " + mountPoint;
+    int result = system(sdMountCommand.c_str());
+    if (result != 0) {
+        utility::handleSystemError(result, "SdCardManager::mountSdCard");
+        return SYSTEM_CALL_ERROR;
+    }
+    return HasReturnvaluesIF::RETURN_OK;
+}
+
+ReturnValue_t SdCardManager::unmountSdCard(sd::SdCard sdCard) {
+    using namespace std;
+    if(sdCard == sd::SdCard::BOTH) {
+        sif::warning << "SdCardManager::unmountSdCard: API does not allow sd::SdStatus::BOTH"
+                << std::endl;
+        return HasReturnvaluesIF::RETURN_FAILED;
+    }
+    string mountPoint;
+    if(sdCard == sd::SdCard::SLOT_0) {
+        mountPoint = SD_0_MOUNT_POINT;
+    }
+    else if(sdCard == sd::SdCard::SLOT_1) {
+        mountPoint = SD_1_MOUNT_POINT;
+    }
+    if(filesystem::is_empty(mountPoint)) {
+        // The mount point will always exist, but if it is empty, that is strong hint that
+        // the SD card was not mounted properly. Still proceed with operation.
+        sif::warning << "SdCardManager::unmountSdCard: Mount point is empty!" << std::endl;
+    }
+    string sdUnmountCommand = "umount " + mountPoint;
+    int result = system(sdUnmountCommand.c_str());
+    if (result != 0) {
+        utility::handleSystemError(result, "SdCardManager::unmountSdCard");
+        return SYSTEM_CALL_ERROR;
+    }
+    return HasReturnvaluesIF::RETURN_OK;
+}
+
+ReturnValue_t SdCardManager::sanitizeState(sd::SdCard* prefSdCard, SdStatusPair* statusPair) {
+    if(prefSdCard == nullptr) {
+        prefSdCard = std::make_unique<sd::SdCard>(sd::SdCard::SLOT_0).get();
+        getPreferredSdCard(*prefSdCard);
+    }
+    if(statusPair == nullptr) {
+        statusPair = std::make_unique<SdStatusPair>().get();
+        getSdCardActiveStatus(*statusPair);
+    }
+
+    auto sanitizerFunc = [&](sd::SdCard prefSdCard) {
+        if(statusPair->first == sd::SdStatus::ON) {
+            return mountSdCard(prefSdCard);
+        }
+        else {
+            return switchOnSdCard(prefSdCard, true, statusPair);
+        }
+    };
+
+    return sanitizerFunc(*prefSdCard);
+}
+
+void SdCardManager::processSdStatusLine(std::pair<sd::SdStatus, sd::SdStatus> &active,
+        std::string& line, uint8_t& idx, sd::SdCard& currentSd) {
+    using namespace std;
+    istringstream iss(line);
+    string word;
+    bool slotLine = false;
+    bool mountLine = false;
+    while(iss >> word) {
+        if (word == "Slot") {
+            slotLine = true;
+        }
+        if(word == "Mounted") {
+            mountLine = true;
+        }
+
+        if(slotLine) {
             if (word == "1:") {
                 currentSd = sd::SdCard::SLOT_1;
             }
 
             if(word == "on") {
                 if(currentSd == sd::SdCard::SLOT_0) {
-                    active.first = true;
+                    active.first = sd::SdStatus::ON;
                 }
                 else {
-                    active.second = true;
+                    active.second = sd::SdStatus::ON;
                 }
             }
             else if (word == "off") {
                 if(currentSd == sd::SdCard::SLOT_0) {
-                    active.first = false;
+                    active.first = sd::SdStatus::OFF;
                 }
                 else {
-                    active.second = false;
+                    active.second = sd::SdStatus::OFF;
                 }
             }
-            else {
+        }
-                continue;
-            }
 
-            if(idx > 3) {
+        if(mountLine) {
-                sif::warning << "SdCardManager::sdCardActive: Status file has more "
+            if(currentSd == sd::SdCard::SLOT_0) {
-                        "than 4 lines!" << std::endl;
+                active.first = sd::SdStatus::MOUNTED;
-                return STATUS_FILE_FORMAT_INVALID;
+            }
+            else {
+                active.second = sd::SdStatus::MOUNTED;
             }
         }
-        idx++;
+
+        if(idx > 5) {
+            sif::warning << "SdCardManager::sdCardActive: /tmp/sd_status.txt has more than 6 "
+                    "lines and might be invalid!" << std::endl;
+        }
     }
+    idx++;
+}
+
+ReturnValue_t SdCardManager::getPreferredSdCard(sd::SdCard& sdCard) const {
+    uint8_t prefSdCard = 0;
+    ReturnValue_t result = scratch::readNumber(scratch::PREFERED_SDC_KEY, prefSdCard);
+    if(result != HasReturnvaluesIF::RETURN_OK) {
+        return result;
+    }
+    sdCard = static_cast<sd::SdCard>(prefSdCard);
     return HasReturnvaluesIF::RETURN_OK;
 }
 
-sd::SdCard SdCardManager::getPreferredSdCard() const {
+ReturnValue_t SdCardManager::setPreferredSdCard(sd::SdCard sdCard) {
-    //int result = std::system("xsc_scratch read PREFSD > /tmp/pref_sd.txt");
+    if(sdCard == sd::SdCard::BOTH) {
-    return preferredSdCard;
+        return HasReturnvaluesIF::RETURN_FAILED;
-}
+    }
-
+    return scratch::writeNumber(scratch::PREFERED_SDC_KEY, static_cast<uint8_t>(sdCard));
-void SdCardManager::setPreferredSdCard(sd::SdCard sdCard) {
-    preferredSdCard = sdCard;
 }
 
 ReturnValue_t SdCardManager::updateSdCardStateFile() {
-    int result = std::system("q7hw sd info all > /tmp/sd_status.txt");
+    // Use q7hw utility and pipe the command output into the state file
+    std::string updateCmd = "q7hw sd info all > " + std::string(SD_STATE_FILE);
+    int result = std::system(updateCmd.c_str());
     if(result == 0) {
         return HasReturnvaluesIF::RETURN_OK;
     }

bsp_q7s/memory/SdCardManager.h

@@ -8,6 +8,7 @@
 
 #include <cstdint>
 #include <utility>
+#include <string>
 
 class MutexIF;
 
@@ -18,16 +19,33 @@ class MutexIF;
 class SdCardManager {
     friend class SdCardAccess;
 public:
+    using SdStatusPair = std::pair<sd::SdStatus, sd::SdStatus>;
+
     static constexpr uint8_t INTERFACE_ID = CLASS_ID::SD_CARD_MANAGER;
 
-    static constexpr ReturnValue_t ALREADY_ON = HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 0);
+    static constexpr ReturnValue_t ALREADY_ON =
-    static constexpr ReturnValue_t ALREADY_OFF = HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 1);
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 0);
-    static constexpr ReturnValue_t STATUS_FILE_NEXISTS =
+    static constexpr ReturnValue_t ALREADY_MOUNTED  =
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 1);
+    static constexpr ReturnValue_t ALREADY_OFF =
             HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 2);
+    static constexpr ReturnValue_t STATUS_FILE_NEXISTS =
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 10);
     static constexpr ReturnValue_t STATUS_FILE_FORMAT_INVALID =
-            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 3);
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 11);
+    static constexpr ReturnValue_t MOUNT_ERROR =
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 12);
+    static constexpr ReturnValue_t UNMOUNT_ERROR =
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 13);
     static constexpr ReturnValue_t SYSTEM_CALL_ERROR =
-            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 4);
+            HasReturnvaluesIF::makeReturnCode(INTERFACE_ID, 14);
+
+    // C++17 does not support constexpr std::string yet
+    static constexpr char SD_0_DEV_NAME[] = "/dev/mmcblk0p1";
+    static constexpr char SD_1_DEV_NAME[] = "/dev/mmcblk1p1";
+    static constexpr char SD_0_MOUNT_POINT[] = "/mnt/sd0";
+    static constexpr char SD_1_MOUNT_POINT[] = "/mnt/sd1";
+    static constexpr char SD_STATE_FILE[] = "/tmp/sd_status.txt";
 
     virtual ~SdCardManager();
 
@@ -38,29 +56,50 @@ public:
      */
     static SdCardManager* instance();
 
-    void setPreferredSdCard(sd::SdCard sdCard);
+    /**
-
+     * Set the preferred SD card which will determine which SD card will be used as the primary
-    sd::SdCard getPreferredSdCard() const;
+     * SD card in hot redundant and cold redundant mode. This function will not switch the
+     * SD cards which are currently on and mounted, this needs to be implemented by
+     * an upper layer by using #switchOffSdCard , #switchOnSdCard and #updateSdCardStateFile
+     * @param sdCard
+     * @return
+     */
+    ReturnValue_t setPreferredSdCard(sd::SdCard sdCard);
 
     /**
-     * Switch on the specified SD card
+     * Get the currently configured preferred SD card
      * @param sdCard
+     * @return
+     */
+    ReturnValue_t getPreferredSdCard(sd::SdCard& sdCard) const;
+
+    /**
+     * Switch on the specified SD card.
+     * @param sdCard
+     * @param doMountSdCard     Mount the SD card after switching it on, which is necessary
+     *                          to use it
+     * @param statusPair        If the status pair is already available, it can be passed here
      * @return - RETURN_OK on success, ALREADY_ON if it is already on,
      *           SYSTEM_CALL_ERROR on system error
      */
-    ReturnValue_t switchOnSdCard(sd::SdCard sdCard);
+    ReturnValue_t switchOnSdCard(sd::SdCard sdCard, bool doMountSdCard = true,
+            SdStatusPair* statusPair = nullptr);
 
     /**
-     * Switch off the specified SD card
+     * Switch off the specified SD card.
      * @param sdCard
+     * @param doUnmountSdCard   Unmount the SD card before switching the card off, which makes
+     *                          the operation safer
+     * @param statusPair        If the status pair is already available, it can be passed here
      * @return - RETURN_OK on success, ALREADY_ON if it is already on,
      *           SYSTEM_CALL_ERROR on system error
      */
-    ReturnValue_t switchOffSdCard(sd::SdCard sdCard);
+    ReturnValue_t switchOffSdCard(sd::SdCard sdCard, bool doUnmountSdCard = true,
+            SdStatusPair* statusPair = nullptr);
 
     /**
-     * Updated the state file or creates one if it does not exist. You need to call this
+     * Update the state file or creates one if it does not exist. You need to call this
-     * function before calling #sdCardActiv
+     * function before calling #sdCardActive
      * @return - RETURN_OK if the state file was updated successfully
      *         - SYSTEM_CALL_ERROR if the call to create the status file failed
      */
@@ -77,16 +116,42 @@ public:
      *           should call #updateSdCardStateFile again in that case
      *         - STATUS_FILE_NEXISTS if the status file does not exist
      */
-    ReturnValue_t sdCardActive(std::pair<bool, bool>& active);
+    ReturnValue_t getSdCardActiveStatus(SdStatusPair& active);
 
-    sd::SdCard getPreferedSdCard() const;
+    /**
+     * Mount the specified SD card. This is necessary to use it.
+     * @param sdCard
+     * @return
+     */
+    ReturnValue_t mountSdCard(sd::SdCard sdCard);
+    /**
+     * Unmount the specified SD card. This is recommended before switching it off. The SD card
+     * can't be used after it has been unmounted.
+     * @param sdCard
+     * @return
+     */
+    ReturnValue_t unmountSdCard(sd::SdCard sdCard);
+
+    /**
+     * In case that there is a discrepancy between the preferred SD card and the currently
+     * mounted one, this function will sanitize the state by attempting to mount the
+     * currently preferred SD card. If the caller already has state information, it can be
+     * passed into the function.
+     * @param prefSdCard    Preferred SD card captured with #getPreferredSdCard
+     * @param statusPair    Current SD card status capture with #getSdCardActiveStatus
+     * @throws std::bad_alloc if one of the two arguments was a nullptr and an allocation failed
+     * @return
+     */
+    ReturnValue_t sanitizeState(sd::SdCard* prefSdCard = nullptr,
+            SdStatusPair* statusPair = nullptr);
 
 private:
     SdCardManager();
 
     ReturnValue_t setSdCardState(sd::SdCard sdCard, bool on);
 
-    sd::SdCard preferredSdCard = sd::SdCard::SLOT_0;
+    void processSdStatusLine(SdStatusPair& active, std::string& line, uint8_t& idx,
+            sd::SdCard& currentSd);
 
     static SdCardManager* factoryInstance;
 };

bsp_q7s/memory/definitions.h

@@ -1,9 +1,18 @@
 #ifndef BSP_Q7S_MEMORY_DEFINITIONS_H_
 #define BSP_Q7S_MEMORY_DEFINITIONS_H_
 
+#include <cstdint>
+
 namespace sd {
 
-enum SdCard {
+enum SdStatus: uint8_t {
+    OFF = 0,
+    ON = 1,
+    // A mounted SD card is on as well
+    MOUNTED = 2
+};
+
+enum SdCard: uint8_t {
     SLOT_0,
     SLOT_1,
     BOTH

bsp_q7s/memory/scratchApi.h

@@ -16,6 +16,8 @@
  */
 namespace scratch {
 
+static constexpr char PREFERED_SDC_KEY[] = "PREFSD";
+
 namespace {
 static uint8_t counter = 0;
 }

fsfw

@@ -1 +1 @@
-Subproject commit eef2fd3b7ac764f06ed5d9a3c97c894d92a515fa
+Subproject commit da8a4470734808bed4d872e47c192af694382c41

linux/fsfwconfig/OBSWConfig.h.in

@@ -14,6 +14,8 @@
 #include "commonConfig.h"
 #include "OBSWVersion.h"
 
+#define OBSW_FILESYSTEM_HANDLER_QUEUE_SIZE  50
+
 /* These defines should be disabled for mission code but are useful for
 debugging. */
 #define OBSW_VERBOSE_LEVEL              1