1 files changed, 84 insertions, 0 deletions
diff --git a/Lessons/Lesson_60/UefiLessonsPkg/SetVariableExample/SetVariableExample.c b/Lessons/Lesson_60/UefiLessonsPkg/SetVariableExample/SetVariableExample.c
new file mode 100644
index 0000000..9c99e52
--- /dev/null
+++ b/Lessons/Lesson_60/UefiLessonsPkg/SetVariableExample/SetVariableExample.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2021, Konstantin Aladyshev <aladyshev22@gmail.com>
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+
+VOID Usage()
+{
+  Print(L"Delete variable\n");
+  Print(L"   SetVariableExample <variable name>\n");
+  Print(L"\n");
+  Print(L"Set variable\n");
+  Print(L"   SetVariableExample <variable name> <attributes> <value>\n");
+  Print(L"\n");
+  Print(L"<attributes> can be <n|b|r>\n");
+  Print(L"n - NON_VOLATILE\n");
+  Print(L"b - BOOTSERVICE_ACCESS\n");
+  Print(L"r - RUNTIME_ACCESS\n");
+}
+
+INTN EFIAPI ShellAppMain(IN UINTN Argc, IN CHAR16 **Argv)
+{
+  EFI_STATUS Status;
+
+  if (Argc==2) {
+    CHAR16* VariableName = Argv[1];
+    Status = gRT->SetVariable (
+                VariableName,
+                &gEfiCallerIdGuid,
+                0,
+                0,
+                NULL
+                );
+    if (EFI_ERROR (Status)) {
+      Print(L"%r\n", Status);
+    } else {
+      Print(L"Variable %s was successfully deleted\n", VariableName);
+    }
+    return Status;
+  } else if (Argc==4) {
+    CHAR16* VariableName = Argv[1];
+    CHAR16* AttributesStr = Argv[2];
+    CHAR16* Value = Argv[3];
+    UINT32  Attributes = 0;
+    for (UINTN i=0; i<StrLen(AttributesStr); i++) {
+      switch(AttributesStr[i]) {
+        case L'n':
+          Attributes |= EFI_VARIABLE_NON_VOLATILE;
+          break;
+        case L'b':
+          Attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
+          break;
+        case L'r':
+          Attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
+          break;
+        default:
+          Print(L"Error! Unknown attribute!");
+          return EFI_INVALID_PARAMETER;
+      }
+    }
+    Status = gRT->SetVariable (
+                VariableName,
+                &gEfiCallerIdGuid,
+                Attributes,
+                StrSize(Value),
+                Value
+                );
+    if (EFI_ERROR (Status)) {
+      Print(L"%r\n", Status);
+    } else {
+      Print(L"Variable %s was successfully changed\n", VariableName);
+    }
+    return Status;
+  } else {
+    Usage();
+  }
+
+  return EFI_SUCCESS;
+}