Added check in the backend to see if write is disabled

src/citra/config.cpp

@@ -63,6 +63,7 @@ void Config::ReadCore() {
 
 void Config::ReadData() {
     Settings::values.use_virtual_sd = glfw_config->GetBoolean("Data Storage", "use_virtual_sd", true);
+    Settings::values.virtual_sd_writable = glfw_config->GetBoolean("Data Storage", "virtual_sd_writable", true);
 }
 
 void Config::Reload() {

src/citra_qt/config.cpp

@@ -82,12 +82,14 @@ void Config::SaveCore() {
 void Config::ReadData() {
     qt_config->beginGroup("Data Storage");
     Settings::values.use_virtual_sd = qt_config->value("use_virtual_sd", true).toBool();
+    Settings::values.virtual_sd_writable = qt_config->value("virtual_sd_writable", true).toBool();
     qt_config->endGroup();
 }
 
 void Config::SaveData() {
     qt_config->beginGroup("Data Storage");
     qt_config->setValue("use_virtual_sd", Settings::values.use_virtual_sd);
+    qt_config->setValue("virtual_sd_writable", Settings::values.virtual_sd_writable);
     qt_config->endGroup();
 }
 

src/core/file_sys/archive_sdmc.cpp

@@ -50,6 +50,11 @@ bool Archive_SDMC::Initialize() {
  * @return Opened file, or nullptr
  */
 std::unique_ptr<File> Archive_SDMC::OpenFile(const std::string& path, const Mode mode) const {
+    if((mode.write_flag || mode.create_flag) && !Settings::values.virtual_sd_writable) {
+        ERROR_LOG(KERNEL, "Cannot open archive %s in write or create mode while the SD card is set to read-only.");
+        return nullptr;
+    }
+    
     DEBUG_LOG(FILESYS, "called path=%s mode=%d", path.c_str(), mode);
     File_SDMC* file = new File_SDMC(this, path, mode);
     if (!file->Open())

src/core/file_sys/file_sdmc.cpp

@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include <sys/stat.h>
+#include <core/settings.h>
 
 #include "common/common_types.h"
 #include "common/file_util.h"
@@ -37,6 +38,11 @@ bool File_SDMC::Open() {
         return false;
     }
 
+    if((mode.write_flag || mode.create_flag) && !Settings::values.virtual_sd_writable) {
+        ERROR_LOG(KERNEL, "Cannot open file %s in write or create mode while the SD card is set to read-only.");
+        return false;
+    }
+
     std::string mode_string;
     if (mode.read_flag && mode.write_flag)
         mode_string = "w+";

src/core/settings.h

@@ -32,6 +32,7 @@ struct Values {
 
     // Data Storage
     bool use_virtual_sd;
+    bool virtual_sd_writable;
 } extern values;
 
 }