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authorKonstantin Aladyshev <aladyshev22@gmail.com>2021-06-23 18:31:23 +0300
committerKonstantin Aladyshev <aladyshev22@gmail.com>2021-06-23 18:31:23 +0300
commitf92ccd087e23c0e3c141b9bcbb85f3f72e0e6817 (patch)
treeccbe732866d29539891c947a388aae4321c2f145
parentf5a4ffca576108c338306d314628861b7e471f2f (diff)
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Add lesson 15
Signed-off-by: Konstantin Aladyshev <aladyshev22@gmail.com>
-rw-r--r--Lesson_15/Conf/target.txt7
-rw-r--r--Lesson_15/README.md400
-rw-r--r--Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.c15
-rw-r--r--Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.inf18
-rw-r--r--Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.c105
-rw-r--r--Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.inf18
-rw-r--r--Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.c44
-rw-r--r--Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.inf22
-rw-r--r--Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.c46
-rw-r--r--Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.inf19
-rw-r--r--Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.c215
-rw-r--r--Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.inf21
-rw-r--r--Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.c93
-rw-r--r--Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf19
-rw-r--r--Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.c14
-rw-r--r--Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf19
-rw-r--r--Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.c10
-rw-r--r--Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.inf16
-rw-r--r--Lesson_15/UefiLessonsPkg/UefiLessonsPkg.dsc36
-rw-r--r--README.md1
20 files changed, 1138 insertions, 0 deletions
diff --git a/Lesson_15/Conf/target.txt b/Lesson_15/Conf/target.txt
new file mode 100644
index 0000000..c109dcf
--- /dev/null
+++ b/Lesson_15/Conf/target.txt
@@ -0,0 +1,7 @@
+ACTIVE_PLATFORM = UefiLessonsPkg/UefiLessonsPkg.dsc
+TARGET = RELEASE
+TARGET_ARCH = X64
+TOOL_CHAIN_CONF = Conf/tools_def.txt
+TOOL_CHAIN_TAG = GCC5
+BUILD_RULE_CONF = Conf/build_rule.txt
+
diff --git a/Lesson_15/README.md b/Lesson_15/README.md
new file mode 100644
index 0000000..2f72644
--- /dev/null
+++ b/Lesson_15/README.md
@@ -0,0 +1,400 @@
+Let's print content of variables that define boot options in UEFI.
+
+To do it, we need to use `GetVariable()` API function from the EFI Runtime Services:
+```
+GetVariable()
+
+Summary:
+Returns the value of a variable.
+
+Prototype:
+typedef
+EFI_STATUS
+GetVariable (
+ IN CHAR16 *VariableName,
+ IN EFI_GUID *VendorGuid,
+ OUT UINT32 *Attributes OPTIONAL,
+ IN OUT UINTN *DataSize,
+ OUT VOID *Data OPTIONAL
+ );
+
+Parameters:
+VariableName A Null-terminated string that is the name of the vendor’s variable.
+VendorGuid A unique identifier for the vendor
+Attributes If not NULL, a pointer to the memory location to return the
+ attributes bitmask for the variable.
+ If not NULL, then Attributes is set on output both when
+ EFI_SUCCESS and when EFI_BUFFER_TOO_SMALL is returned.
+DataSize On input, the size in bytes of the return Data buffer.
+ On output the size of data returned in Data.
+Data The buffer to return the contents of the variable. May be NULL
+ with a zero DataSize in order to determine the size buffer needed.
+
+Description:
+Each vendor may create and manage its own variables without the risk of name conflicts by using a
+unique VendorGuid. When a variable is set its Attributes are supplied to indicate how the data variable
+should be stored and maintained by the system. The attributes affect when the variable may be accessed
+and volatility of the data
+
+If the Data buffer is too small to hold the contents of the variable, the error EFI_BUFFER_TOO_SMALL is
+returned and DataSize is set to the required buffer size to obtain the data.
+
+Status Codes Returned:
+EFI_SUCCESS The function completed successfully.
+EFI_NOT_FOUND The variable was not found.
+EFI_BUFFER_TOO_SMALL The DataSize is too small for the result. DataSize has been
+ updated with the size needed to complete the request. If
+ Attributes is not NULL, then the attributes bitmask for the
+ variable has been stored to the memory location pointed-to by
+ Attributes.
+...
+
+```
+
+In previous lesson we've discovered that these options are present in our environment under GUID `EFI_GLOBAL_VARIABLE` (gEfiGlobalVariableGuid):
+```
+Boot0000
+Boot0001
+Boot0002
+Boot0003
+Boot0004
+BootCurrent
+BootOrder
+```
+
+If we look at the UEFI spec for these options description we would find:
+```
+Each Boot#### variable contains an EFI_LOAD_OPTION. Each Boot#### variable is the name “Boot”
+appended with a unique four digit hexadecimal number. For example, Boot0001, Boot0002, Boot0A02,
+etc.
+
+...
+
+The BootOrder variable contains an array of UINT16’s that make up an ordered list of the Boot####
+options. The first element in the array is the value for the first logical boot option, the second element is
+the value for the second logical boot option, etc. The BootOrder order list is used by the firmware’s
+boot manager as the default boot order.
+
+...
+
+The BootCurrent variable is a single UINT16 that defines the Boot#### option that was selected on
+the current boot.
+```
+
+Create `ShowBootVariables` for this lesson.
+
+First let's try to get simple `UINT16 BootCurrent` option.
+
+We would be getting variables a lot in this program, so it is best to create a function that abstracts all the necessities of the `GetVariable` API calls:
+```
+EFI_STATUS
+GetNvramVariable( CHAR16 *VariableName,
+ EFI_GUID *VariableOwnerGuid,
+ VOID **Buffer,
+ UINTN *BufferSize)
+{
+ UINTN Size = 0;
+ *BufferSize = 0;
+
+ EFI_STATUS Status = gRT->GetVariable(VariableName, VariableOwnerGuid, NULL, &Size, NULL);
+ if (Status != EFI_BUFFER_TOO_SMALL) {
+ Print(L"Error! 'gRT->GetVariable' call returned %r\n", Status);
+ return Status;
+ }
+
+ *Buffer = AllocateZeroPool(Size);
+ if (!Buffer) {
+ Print(L"Error! 'AllocateZeroPool' call returned %r\n", Status);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ Status = gRT->GetVariable(VariableName, VariableOwnerGuid, NULL, &Size, *Buffer);
+ if (Status == EFI_SUCCESS) {
+ *BufferSize = Size;
+ } else {
+ FreePool( *Buffer );
+ *Buffer = NULL;
+ }
+
+ return Status;
+}
+```
+
+As with many other different UEFI APIs first `GetVariable` call gives us `EFI_BUFFER_TOO_SMALL` error, but fills `Size` variable with the size of the array that we need to allocate and pass to this function for the correct execution.
+We allocate necessary size with the `AllocateZeroPool` edk2 library call, like we did it in previous lesson. After that we call `GetVariable` function for the second time, expecting `EFI_SUCCESS` status.
+
+
+The main function would look like this:
+```
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+#include <Library/MemoryAllocationLib.h>
+
+EFI_STATUS
+GetNvramVariable( CHAR16 *VariableName,
+ EFI_GUID *VariableOwnerGuid,
+ VOID **Buffer,
+ UINTN *BufferSize)
+{
+ ...
+}
+
+INTN EFIAPI ShellAppMain(IN UINTN Argc, IN CHAR16 **Argv)
+{
+ UINTN OptionSize;
+ EFI_STATUS Status;
+
+ UINT16* BootCurrent;
+ Status = GetNvramVariable(L"BootCurrent", &gEfiGlobalVariableGuid, (VOID**)&BootCurrent, &OptionSize);
+ if (Status == EFI_SUCCESS) {
+ Print(L"BootCurrent=%d\n", *BootCurrent);
+ } else {
+ Print(L"Can't get BootCurrent variable\n");
+ }
+
+ return EFI_SUCCESS;
+}
+```
+
+If we execute this code under OVMF we would get:
+```
+FS0:\> ShowBootVariables.efi
+3
+```
+This means that `Boot0003` is active.
+
+
+Now let's get `UINT16 BootOrder[]` variable. It is an array of XXXX numbers that describe Boot option priority.
+So `{0,2,4,1,3}` for example would mean this order:
+```
+Boot0000
+Boot0002
+Boot0004
+Boot0001
+Boot0003
+```
+
+This is the code to get and print this array:
+```
+UINT16* BootOrderArray;
+Status = GetNvramVariable(L"BootOrder", &gEfiGlobalVariableGuid, (VOID**)&BootOrderArray, &OptionSize);
+if (Status == EFI_SUCCESS) {
+ for (UINTN i=0; i<(OptionSize/sizeof(UINT16)); i++) {
+ Print(L"Boot%04d%s\n", BootOrderArray[i], (BootOrderArray[i] == *BootCurrent)? L"*" : L"" );
+ }
+} else {
+ Print(L"Can't get BootOrder variable\n");
+}
+```
+
+If we execute this code under OVMF we would get:
+```
+Boot0000
+Boot0001
+Boot0002
+Boot0003*
+Boot0004
+```
+
+
+Now let's print information about every `Boot####` option.
+
+According to the UEFI the spec these options are stored in a `EFI_LOAD_OPTION` structure:
+```
+typedef struct _EFI_LOAD_OPTION {
+ UINT32 Attributes;
+ UINT16 FilePathListLength;
+ // CHAR16 Description[];
+ // EFI_DEVICE_PATH_PROTOCOL FilePathList[];
+ // UINT8 OptionalData[];
+} EFI_LOAD_OPTION;
+
+Parameters
+Attributes The attributes for this load option entry. All unused bits must be zero
+ and are reserved by the UEFI specification for future growth.
+FilePathListLength Length in bytes of the FilePathList. OptionalData starts at
+ offset sizeof(UINT32) + sizeof(UINT16) +
+ StrSize(Description) + FilePathListLength of the
+ EFI_LOAD_OPTION descriptor.
+Description The user readable description for the load option. This field ends
+ with a Null character.
+FilePathList A packed array of UEFI device paths. The first element of the array is
+ a device path that describes the device and location of the Image for
+ this load option. The FilePathList[0] is specific to the device
+ type. Other device paths may optionally exist in the FilePathList,
+ but their usage is OSV specific. Each element in the array is variable
+ length, and ends at the device path end structure. Because the size
+ of Description is arbitrary, this data structure is not guaranteed
+ to be aligned on a natural boundary. This data structure may have to
+ be copied to an aligned natural boundary before it is used.
+OptionalData The remaining bytes in the load option descriptor are a binary data
+ buffer that is passed to the loaded image. If the field is zero bytes
+ long, a NULL pointer is passed to the loaded image. The number of
+ bytes in OptionalData can be computed by subtracting the
+ starting offset of OptionalData from total size in bytes of the
+ EFI_LOAD_OPTION.
+```
+
+Pay attention to the fact that some fields in this structure are commented:
+```
+// CHAR16 Description[];
+// EFI_DEVICE_PATH_PROTOCOL FilePathList[];
+// UINT8 OptionalData[];
+```
+It is because these fields are variable size arrays, so we need to calculate offsets to them dynamically.
+
+Create a function that accepts names of a Boot variable (such as "Boot0003") and outputs all the needed information about it:
+```
+VOID PrintBootOption(CHAR16* BootOptionName)
+{
+ UINTN OptionSize;
+ UINT8* Buffer;
+
+ EFI_STATUS Status = GetNvramVariable(BootOptionName, &gEfiGlobalVariableGuid, (VOID**)&Buffer, &OptionSize);
+ if (Status == EFI_SUCCESS) {
+ EFI_LOAD_OPTION* LoadOption = (EFI_LOAD_OPTION*) Buffer;
+ CHAR16* Description = (CHAR16*)(Buffer + sizeof (EFI_LOAD_OPTION));
+ UINTN DescriptionSize = StrSize(Description);
+
+ Print(L"%s\n", Description);
+ if (LoadOption->FilePathListLength != 0) {
+ VOID* FilePathList = (UINT8 *)Description + DescriptionSize;
+ CHAR16* DevPathString = ConvertDevicePathToText(FilePathList, TRUE, FALSE);
+ Print(L"%s\n", DevPathString);
+ }
+ } else {
+ Print(L"Can't get %s variable\n", BootOptionName);
+ }
+}
+```
+
+This code uses pointer arithmetics that we've discussed above. To get `Description` field size we simply use `StrSize(Description)` call as `Description` field always ends with Null.
+
+To print DevicePath as a string we use `ConvertDevicePathToText` call (we've used it earlier in our `ImageInfo` application). To use it we need to add `#include <Library/DevicePathLib.h>` to our program.
+
+Now we need to construct "BootXXXX" variables from a `BootOrder` numbers.
+
+To do so we would use `UnicodeSPrint` function from the https://github.com/tianocore/edk2/blob/master/MdePkg/Include/Library/PrintLib.h
+```
+/**
+ Produces a Null-terminated Unicode string in an output buffer based on a Null-terminated
+ Unicode format string and variable argument list.
+ This function is similar as snprintf_s defined in C11.
+
+ ...
+
+ @param StartOfBuffer A pointer to the output buffer for the produced Null-terminated
+ Unicode string.
+ @param BufferSize The size, in bytes, of the output buffer specified by StartOfBuffer.
+ @param FormatString A Null-terminated Unicode format string.
+ @param ... Variable argument list whose contents are accessed based on the
+ format string specified by FormatString.
+ @return The number of Unicode characters in the produced output buffer not including the
+ Null-terminator.
+**/
+
+UINTN
+EFIAPI
+UnicodeSPrint (
+ OUT CHAR16 *StartOfBuffer,
+ IN UINTN BufferSize,
+ IN CONST CHAR16 *FormatString,
+ ...
+ );
+```
+
+Just in case in the same file there is a similar function for ASCII:
+```
+UINTN
+EFIAPI
+AsciiSPrint (
+ OUT CHAR8 *StartOfBuffer,
+ IN UINTN BufferSize,
+ IN CONST CHAR8 *FormatString,
+ ...
+ );
+```
+
+
+So the code inside BootOrder loop now would look like this:
+```
+CHAR16 BootOptionStr[sizeof("Boot####")+1];
+UnicodeSPrint(BootOptionStr, (sizeof("Boot####")+1)*sizeof(CHAR16), L"Boot%04x", BootOrderArray[i]);
+Print(L"%s%s\n", BootOptionStr, (BootOrderArray[i] == *BootCurrent)? L"*" : L"" );
+PrintBootOption(BootOptionStr);
+Print(L"\n");
+```
+
+Don't forget to add `#include <Library/PrintLib.h>` to the start of the file.
+
+
+If we compile our app and execute it under OVMF we would get:
+```
+FS0:\> ShowBootVariables.efi
+Boot0000
+UiApp
+Fv(7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1)/FvFile(462CAA21-7614-4503-836E-8AB6F4662331)
+
+Boot0001
+UEFI QEMU DVD-ROM QM00003
+PciRoot(0x0)/Pci(0x1,0x1)/Ata(0x0)
+
+Boot0002
+UEFI QEMU HARDDISK QM00001
+PciRoot(0x0)/Pci(0x1,0x1)/Ata(0x0)
+
+Boot0003*
+EFI Internal Shell
+Fv(7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1)/FvFile(7C04A583-9E3E-4F1C-AD65-E05268D0B4D1)
+
+Boot0004
+UEFI PXEv4 (MAC:525400123456)
+PciRoot(0x0)/Pci(0x3,0x0)/MAC(525400123456,0x1)/IPv4(0.0.0.0)
+```
+
+We are definitely in the UEFI shell, so the `BootCurrent`(="*") is placed correctly.
+
+If you want to know information about the printed GUIDs here it is:
+- `FILE_GUID = 7C04A583-9E3E-4f1c-AD65-E05268D0B4D1 # gUefiShellFileGuid`
+https://github.com/tianocore/edk2/blob/master/ShellPkg/Application/Shell/Shell.inf
+- `FILE_GUID = 462CAA21-7614-4503-836E-8AB6F4662331` - UiApp module is driver for BDS phase
+https://github.com/tianocore/edk2/blob/master/MdeModulePkg/Application/UiApp/UiApp.inf
+
+
+As for the `7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1` it is a GUID for the firmware volume in our OVMF image.
+https://github.com/tianocore/edk2/blob/master/OvmfPkg/OvmfPkgX64.fdf
+
+This *.fdf file lists what drivers/apps are placed in every volume in the image (this includes volumes for SEC, PEI or DXE stages):
+```
+...
+
+[FV.SECFV]
+FvNameGuid = 763BED0D-DE9F-48F5-81F1-3E90E1B1A015
+BlockSize = 0x1000
+FvAlignment = 16
+...
+INF <...>
+...
+
+[FV.PEIFV]
+FvNameGuid = 6938079B-B503-4E3D-9D24-B28337A25806
+BlockSize = 0x10000
+FvAlignment = 16
+...
+INF <...>
+...
+
+[FV.DXEFV]
+FvForceRebase = FALSE
+FvNameGuid = 7CB8BDC9-F8EB-4F34-AAEA-3EE4AF6516A1 ### <---- this is a GUID from our output
+BlockSize = 0x10000
+FvAlignment = 16
+...
+INF ShellPkg/Application/Shell/Shell.inf <--- this apps are placed in the FV.DXEFV firmware volume
+...
+INF MdeModulePkg/Application/UiApp/UiApp.inf
+```
+
+For the complete edk2 FDF file specification look at the https://edk2-docs.gitbook.io/edk-ii-fdf-specification/
+
diff --git a/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.c b/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.c
new file mode 100644
index 0000000..1f05899
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.c
@@ -0,0 +1,15 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ SystemTable->ConOut->OutputString(SystemTable->ConOut, L"Hello World!\n");
+ gST->ConOut->OutputString(gST->ConOut, L"Hello again!\n");
+ Print(L"Bye!\n");
+ return EFI_SUCCESS;
+}
diff --git a/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.inf b/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.inf
new file mode 100644
index 0000000..d65ca2e
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/HelloWorld/HelloWorld.inf
@@ -0,0 +1,18 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = HelloWorld
+ FILE_GUID = 2e55fa38-f148-42d3-af90-1be247323e30
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ HelloWorld.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
diff --git a/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.c b/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.c
new file mode 100644
index 0000000..32e9c43
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.c
@@ -0,0 +1,105 @@
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+typedef struct {
+ UINTN Signature;
+ /// All handles list of IHANDLE
+ LIST_ENTRY AllHandles;
+ /// List of PROTOCOL_INTERFACE's for this handle
+ LIST_ENTRY Protocols;
+ UINTN LocateRequest;
+ /// The Handle Database Key value when this handle was last created or modified
+ UINT64 Key;
+} IHANDLE;
+
+typedef struct {
+ UINTN Signature;
+ /// Link Entry inserted to mProtocolDatabase
+ LIST_ENTRY AllEntries;
+ /// ID of the protocol
+ EFI_GUID ProtocolID;
+ /// All protocol interfaces
+ LIST_ENTRY Protocols;
+ /// Registerd notification handlers
+ LIST_ENTRY Notify;
+} PROTOCOL_ENTRY;
+
+typedef struct {
+ UINTN Signature;
+ /// Link on IHANDLE.Protocols
+ LIST_ENTRY Link;
+ /// Back pointer
+ IHANDLE *Handle;
+ /// Link on PROTOCOL_ENTRY.Protocols
+ LIST_ENTRY ByProtocol;
+ /// The protocol ID
+ PROTOCOL_ENTRY *Protocol;
+ /// The interface value
+ VOID *Interface;
+ /// OPEN_PROTOCOL_DATA list
+ LIST_ENTRY OpenList;
+ UINTN OpenListCount;
+
+} PROTOCOL_INTERFACE;
+
+
+#define offsetof(a,b) ((INTN)(&(((a*)(0))->b)))
+
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+ (type *)( (char *)__mptr - offsetof(type,member) );})
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ IHANDLE* MyHandle = ImageHandle;
+ Print(L"Signature: %c %c %c %c\n", (MyHandle->Signature >> 0) & 0xff,
+ (MyHandle->Signature >> 8) & 0xff,
+ (MyHandle->Signature >> 16) & 0xff,
+ (MyHandle->Signature >> 24) & 0xff);
+
+ Print(L"Back Protocol Interface Link: %p\n", MyHandle->Protocols.BackLink);
+ Print(L"Forward Protocol Interface Link: %p\n", MyHandle->Protocols.ForwardLink);
+
+ LIST_ENTRY *FirstLink = MyHandle->Protocols.ForwardLink;
+ LIST_ENTRY *CurrentLink = FirstLink;
+ do {
+ PROTOCOL_INTERFACE* MyProtocolInterface = container_of(CurrentLink, PROTOCOL_INTERFACE, Link);
+
+ Print(L"\n");
+ Print(L"Current Link: %p\n", CurrentLink);
+ Print(L"Signature: %x %x %x %x\n", (MyProtocolInterface->Signature >> 0) & 0xff,
+ (MyProtocolInterface->Signature >> 8) & 0xff,
+ (MyProtocolInterface->Signature >> 16) & 0xff,
+ (MyProtocolInterface->Signature >> 24) & 0xff);
+
+ Print(L"Back Link: %p\n", MyProtocolInterface->Link.BackLink);
+ Print(L"Forward Link: %p\n", MyProtocolInterface->Link.ForwardLink);
+ Print(L"GUID=%g\n", MyProtocolInterface->Protocol->ProtocolID);
+ CurrentLink = MyProtocolInterface->Link.ForwardLink;
+ } while (CurrentLink != FirstLink);
+
+ Print(L"________\n");
+ EFI_GUID **ProtocolGuidArray;
+ UINTN ArrayCount;
+ //EFI_STATUS Status = gBS->ProtocolsPerHandle(NULL, // Use this to test %r Print formatting option
+ EFI_STATUS Status = gBS->ProtocolsPerHandle(ImageHandle,
+ &ProtocolGuidArray,
+ &ArrayCount);
+
+ if (!EFI_ERROR(Status)) {
+ for (int i=0; i<ArrayCount; i++) {
+ Print(L"%g\n", ProtocolGuidArray[i]);
+ }
+ FreePool(ProtocolGuidArray);
+ } else {
+ Print(L"ProtocolsPerHandle error: %r\n", Status);
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.inf b/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.inf
new file mode 100644
index 0000000..34256ee
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ImageHandle/ImageHandle.inf
@@ -0,0 +1,18 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = ImageHandle
+ FILE_GUID = b68d3472-70c7-4928-841b-6566032e0a23
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ ImageHandle.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
diff --git a/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.c b/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.c
new file mode 100644
index 0000000..c45570e
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.c
@@ -0,0 +1,44 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Protocol/LoadedImage.h>
+#include <Library/DevicePathLib.h>
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_LOADED_IMAGE_PROTOCOL* LoadedImage;
+
+ Status = gBS->HandleProtocol(
+ ImageHandle,
+ &gEfiLoadedImageProtocolGuid,
+ (VOID **) &LoadedImage
+ );
+
+ if (Status == EFI_SUCCESS) {
+ EFI_DEVICE_PATH_PROTOCOL* DevicePath;
+
+ Status = gBS->HandleProtocol(
+ ImageHandle,
+ &gEfiLoadedImageDevicePathProtocolGuid,
+ (VOID**) &DevicePath
+ );
+
+ if (Status == EFI_SUCCESS) {
+ Print(L"Image device: %s\n", ConvertDevicePathToText(DevicePath, FALSE, TRUE));
+ Print(L"Image file: %s\n", ConvertDevicePathToText(LoadedImage->FilePath, FALSE, TRUE)); // EFI_DEVICE_PATH_PROTOCOL *FilePath
+ Print(L"Image Base: %X\n", LoadedImage->ImageBase);
+ Print(L"Image Size: %X\n", LoadedImage->ImageSize);
+ } else {
+ Print(L"Can't get EFI_LOADED_IMAGE_PROTOCOL, Status=%r\n", Status);
+ }
+ } else {
+ Print(L"Can't get EFI_DEVICE_PATH_PROTOCOL, Status=%r\n", Status);
+ }
+ return EFI_SUCCESS;
+}
diff --git a/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.inf b/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.inf
new file mode 100644
index 0000000..0ce54a6
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ImageInfo/ImageInfo.inf
@@ -0,0 +1,22 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = ImageInfo
+ FILE_GUID = b68d3472-70c7-4928-841b-6566032e0a23
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ ImageInfo.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
+[Protocols]
+ gEfiLoadedImageProtocolGuid
+ gEfiLoadedImageDevicePathProtocolGuid
+
diff --git a/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.c b/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.c
new file mode 100644
index 0000000..1f3ef4a
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.c
@@ -0,0 +1,46 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+INTN EFIAPI ShellAppMain(IN UINTN Argc, IN CHAR16 **Argv)
+{
+ EFI_GUID VendorGuid;
+ UINTN VariableNameSize = sizeof (CHAR16);
+ CHAR16* VariableName = AllocateZeroPool(sizeof(CHAR16));
+ if (VariableName == NULL) {
+ Print(L"Error on AllocateZeroPool call\n");
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ while (TRUE)
+ {
+ UINTN VariableNameSizeOld = VariableNameSize;
+ EFI_STATUS Status = gRT->GetNextVariableName(&VariableNameSize, VariableName, &VendorGuid);
+ if (Status == EFI_SUCCESS) {
+ Print(L"%g: %s\n", VendorGuid, VariableName);
+ } else if (Status == EFI_BUFFER_TOO_SMALL) {
+ VariableName = ReallocatePool(VariableNameSizeOld, VariableNameSize, VariableName);
+ if (VariableName == NULL) {
+ Print(L"Error on ReallocatePool call\n");
+ return EFI_OUT_OF_RESOURCES;
+ }
+ Status = gRT->GetNextVariableName(&VariableNameSize, VariableName, &VendorGuid);
+ if (Status == EFI_SUCCESS) {
+ Print(L"%g: %s\n", VendorGuid, VariableName);
+ } else {
+ Print(L"Error on 'gRT->GetNextVariableName' call: %s\n", Status);
+ return Status;
+ }
+ } else if (Status == EFI_NOT_FOUND) {
+ FreePool(VariableName);
+ return EFI_SUCCESS;
+ } else {
+ Print(L"Error on 'gRT->GetNextVariableName' call: %s\n", Status);
+ return Status;
+ }
+ }
+ return EFI_SUCCESS;
+}
diff --git a/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.inf b/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.inf
new file mode 100644
index 0000000..14e9fa2
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ListVariables/ListVariables.inf
@@ -0,0 +1,19 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = ListVariables
+ FILE_GUID = d66f68b2-3591-45af-bf5d-519152b9d877
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = ShellCEntryLib
+
+[Sources]
+ ListVariables.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+ ShellCEntryLib
+
diff --git a/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.c b/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.c
new file mode 100644
index 0000000..8c3bcf2
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.c
@@ -0,0 +1,215 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+// for SetMem
+#include <Library/BaseMemoryLib.h>
+
+#include <Protocol/ShellParameters.h>
+
+const CHAR16 *memory_types[] = {
+ L"EfiReservedMemoryType",
+ L"EfiLoaderCode",
+ L"EfiLoaderData",
+ L"EfiBootServicesCode",
+ L"EfiBootServicesData",
+ L"EfiRuntimeServicesCode",
+ L"EfiRuntimeServicesData",
+ L"EfiConventionalMemory",
+ L"EfiUnusableMemory",
+ L"EfiACPIReclaimMemory",
+ L"EfiACPIMemoryNVS",
+ L"EfiMemoryMappedIO",
+ L"EfiMemoryMappedIOPortSpace",
+ L"EfiPalCode",
+ L"EfiPersistentMemory",
+ L"EfiMaxMemoryType"
+};
+
+
+const CHAR16 *memory_types_OS_view[] = {
+ L"reserved", // L"EfiReservedMemoryType",
+ L"usable", // L"EfiLoaderCode",
+ L"usable", // L"EfiLoaderData",
+ L"usable", // L"EfiBootServicesCode",
+ L"usable", // L"EfiBootServicesData",
+ L"reserved", // L"EfiRuntimeServicesCode",
+ L"reserved", // L"EfiRuntimeServicesData",
+ L"usable", // L"EfiConventionalMemory",
+ L"reserved", // L"EfiUnusableMemory",
+ L"ACPI data",// L"EfiACPIReclaimMemory",
+ L"ACPI NVS", // L"EfiACPIMemoryNVS",
+ L"reserved", // L"EfiMemoryMappedIO",
+ L"reserved", // L"EfiMemoryMappedIOPortSpace",
+ L"reserved", // L"EfiPalCode",
+ L"usable", // L"EfiPersistentMemory",
+ L"usable", // L"EfiMaxMemoryType"
+};
+
+
+const CHAR16 *
+memory_type_to_str(UINT32 type)
+{
+ if (type > sizeof(memory_types)/sizeof(CHAR16 *))
+ return L"Unknown";
+
+ return memory_types[type];
+}
+
+const CHAR16 *
+memory_type_to_str_OS_view(UINT32 type)
+{
+ if (type > sizeof(memory_types_OS_view)/sizeof(CHAR16 *))
+ return L"Unknown";
+
+ return memory_types_OS_view[type];
+}
+
+#define ATTRIBUTE_STR_SIZE 50
+
+#define CHECK_EFI_MEMORY_ATTRIBUTE(attr) if (attrs & EFI_MEMORY_##attr) { \
+ StrCpyS(&str[i], ATTRIBUTE_STR_SIZE, L" "#attr); \
+ i+=StrLen(L" "#attr); \
+ }
+
+const CHAR16 *
+memory_attrs_to_str(CHAR16* str, UINT64 attrs)
+{
+ int i=0;
+ SetMem((VOID *)str, sizeof(str), 0);
+
+ CHECK_EFI_MEMORY_ATTRIBUTE(UC)
+ CHECK_EFI_MEMORY_ATTRIBUTE(WC)
+ CHECK_EFI_MEMORY_ATTRIBUTE(WT)
+ CHECK_EFI_MEMORY_ATTRIBUTE(WB)
+ CHECK_EFI_MEMORY_ATTRIBUTE(UCE)
+ CHECK_EFI_MEMORY_ATTRIBUTE(WP)
+ CHECK_EFI_MEMORY_ATTRIBUTE(RP)
+ CHECK_EFI_MEMORY_ATTRIBUTE(XP)
+ CHECK_EFI_MEMORY_ATTRIBUTE(NV)
+ CHECK_EFI_MEMORY_ATTRIBUTE(MORE_RELIABLE)
+ CHECK_EFI_MEMORY_ATTRIBUTE(RO)
+ CHECK_EFI_MEMORY_ATTRIBUTE(SP)
+ CHECK_EFI_MEMORY_ATTRIBUTE(CPU_CRYPTO)
+ CHECK_EFI_MEMORY_ATTRIBUTE(RUNTIME)
+
+ return str;
+}
+
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ UINTN MemoryMapSize = 0;
+ EFI_MEMORY_DESCRIPTOR* MemoryMap = NULL;
+ UINTN MapKey;
+ UINTN DescriptorSize;
+ UINT32 DescriptorVersion;
+
+ EFI_STATUS Status;
+
+
+ EFI_SHELL_PARAMETERS_PROTOCOL* ShellParameters;
+
+ Status = gBS->HandleProtocol(
+ ImageHandle,
+ &gEfiShellParametersProtocolGuid,
+ (VOID **) &ShellParameters
+ );
+
+ BOOLEAN full=FALSE;
+ if (Status == EFI_SUCCESS) {
+ if (ShellParameters->Argc == 2) {
+ if (!StrCmp(ShellParameters->Argv[1], L"full")) {
+ full=TRUE;
+ }
+ }
+ }
+
+
+ Status = gBS->GetMemoryMap(
+ &MemoryMapSize,
+ MemoryMap,
+ &MapKey,
+ &DescriptorSize,
+ &DescriptorVersion
+ );
+
+ if (Status == EFI_BUFFER_TOO_SMALL) {
+ Status = gBS->AllocatePool(
+ EfiBootServicesData,
+ MemoryMapSize,
+ (void**)&MemoryMap
+ );
+
+ if (EFI_ERROR(Status)) {
+ Print(L"AllocatePool error: %r\n", Status);
+ return Status;
+ }
+
+ Status = gBS->GetMemoryMap(
+ &MemoryMapSize,
+ MemoryMap,
+ &MapKey,
+ &DescriptorSize,
+ &DescriptorVersion
+ );
+
+ if (!EFI_ERROR(Status))
+ {
+ EFI_MEMORY_DESCRIPTOR* desc = MemoryMap;
+ EFI_MEMORY_DESCRIPTOR* next_desc;
+ int i = 0;
+ while ((UINT8 *)desc < (UINT8 *)MemoryMap + MemoryMapSize) {
+ UINTN PAGE_SIZE = 4096;
+ UINTN mapping_size =(UINTN) desc->NumberOfPages * PAGE_SIZE;
+
+ UINT64 Start = desc->PhysicalStart;
+
+ next_desc = (EFI_MEMORY_DESCRIPTOR *)((UINT8 *)desc + DescriptorSize);
+ if (!full) {
+ while ((UINT8 *)next_desc < (UINT8 *)MemoryMap + MemoryMapSize) {
+ mapping_size =(UINTN) desc->NumberOfPages * PAGE_SIZE;
+ if ((desc->PhysicalStart + mapping_size) == (next_desc->PhysicalStart)) {
+
+ if (desc->Type != next_desc->Type) {
+ if (StrCmp(memory_type_to_str_OS_view(desc->Type),
+ memory_type_to_str_OS_view(next_desc->Type)))
+ break;
+ }
+
+ desc=next_desc;
+ next_desc = (EFI_MEMORY_DESCRIPTOR *)((UINT8 *)next_desc + DescriptorSize);
+ } else {
+ break;
+ }
+ }
+ }
+
+ if (full) {
+ CHAR16 str[ATTRIBUTE_STR_SIZE];
+ Print(L"[#%02d] Type: %s Attr: %s\n", i++,
+ memory_type_to_str(desc->Type), memory_attrs_to_str(str, desc->Attribute));
+ Print(L" Phys: %016llx-%016llx\n", Start, Start + mapping_size - 1);
+ }
+ else {
+ Print(L" [mem: %016llx-%016llx] %s\n", Start, desc->PhysicalStart + mapping_size - 1,
+ memory_type_to_str_OS_view(desc->Type) );
+ }
+
+ desc = next_desc;
+ }
+
+ gBS->FreePool(MemoryMap);
+ } else {
+ Print(L"GetMemoryMap with buffer error: %r\n", Status);
+ }
+ } else {
+ Print(L"GetMemoryMap without buffer error: %r\n", Status);
+ }
+
+ return Status;
+}
+
diff --git a/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.inf b/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.inf
new file mode 100644
index 0000000..777010d
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/MemoryInfo/MemoryInfo.inf
@@ -0,0 +1,21 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = MemoryInfo
+ FILE_GUID = d2ce1d65-603e-4b48-b3e1-fe65d5d0bca8
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ MemoryInfo.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+
+[Protocols]
+ gEfiShellParametersProtocolGuid
+
diff --git a/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.c b/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.c
new file mode 100644
index 0000000..7f6b58c
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.c
@@ -0,0 +1,93 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+#include <Library/DevicePathLib.h>
+#include <Library/PrintLib.h>
+
+
+EFI_STATUS
+GetNvramVariable( CHAR16 *VariableName,
+ EFI_GUID *VariableOwnerGuid,
+ VOID **Buffer,
+ UINTN *BufferSize)
+{
+ UINTN Size = 0;
+ *BufferSize = 0;
+
+ EFI_STATUS Status = gRT->GetVariable(VariableName, VariableOwnerGuid, NULL, &Size, NULL);
+ if (Status != EFI_BUFFER_TOO_SMALL) {
+ Print(L"Error! 'gRT->GetVariable' call returned %r\n", Status);
+ return Status;
+ }
+
+ *Buffer = AllocateZeroPool(Size);
+ if (!Buffer) {
+ Print(L"Error! 'AllocateZeroPool' call returned %r\n", Status);
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ Status = gRT->GetVariable(VariableName, VariableOwnerGuid, NULL, &Size, *Buffer);
+ if (Status == EFI_SUCCESS) {
+ *BufferSize = Size;
+ } else {
+ FreePool( *Buffer );
+ *Buffer = NULL;
+ }
+
+ return Status;
+}
+
+
+VOID PrintBootOption(CHAR16* BootOptionName)
+{
+ UINTN OptionSize;
+ UINT8* Buffer;
+
+ EFI_STATUS Status = GetNvramVariable(BootOptionName, &gEfiGlobalVariableGuid, (VOID**)&Buffer, &OptionSize);
+ if (Status == EFI_SUCCESS) {
+ EFI_LOAD_OPTION* LoadOption = (EFI_LOAD_OPTION*) Buffer;
+ CHAR16* Description = (CHAR16*)(Buffer + sizeof (EFI_LOAD_OPTION));
+ UINTN DescriptionSize = StrSize(Description);
+
+ Print(L"%s\n", Description);
+ if (LoadOption->FilePathListLength != 0) {
+ VOID* FilePathList = (UINT8 *)Description + DescriptionSize;
+ CHAR16* DevPathString = ConvertDevicePathToText(FilePathList, TRUE, FALSE);
+ Print(L"%s\n", DevPathString);
+ }
+ } else {
+ Print(L"Can't get %s variable\n", BootOptionName);
+ }
+}
+
+
+INTN EFIAPI ShellAppMain(IN UINTN Argc, IN CHAR16 **Argv)
+{
+ UINTN OptionSize;
+ EFI_STATUS Status;
+
+ UINT16* BootCurrent;
+ Status = GetNvramVariable(L"BootCurrent", &gEfiGlobalVariableGuid, (VOID**)&BootCurrent, &OptionSize);
+ if (Status != EFI_SUCCESS) {
+ Print(L"Can't get BootCurrent variable\n");
+ }
+
+ UINT16* BootOrderArray;
+ Status = GetNvramVariable(L"BootOrder", &gEfiGlobalVariableGuid, (VOID**)&BootOrderArray, &OptionSize);
+ if (Status == EFI_SUCCESS) {
+ for (UINTN i=0; i<(OptionSize/sizeof(UINT16)); i++) {
+ CHAR16 BootOptionStr[sizeof("Boot####")+1];
+ UnicodeSPrint(BootOptionStr, (sizeof("Boot####")+1)*sizeof(CHAR16), L"Boot%04x", BootOrderArray[i]);
+ Print(L"%s%s\n", BootOptionStr, (BootOrderArray[i] == *BootCurrent)? L"*" : L"" );
+ PrintBootOption(BootOptionStr);
+ Print(L"\n");
+ }
+ } else {
+ Print(L"Can't get BootOrder variable\n");
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf b/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf
new file mode 100644
index 0000000..d2cfba9
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf
@@ -0,0 +1,19 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = ShowBootVariables
+ FILE_GUID = 31266d12-9c60-478e-905e-05d117a3a9df
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = ShellCEntryLib
+
+[Sources]
+ ShowBootVariables.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+ ShellCEntryLib
+
diff --git a/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.c b/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.c
new file mode 100644
index 0000000..b13aa6c
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.c
@@ -0,0 +1,14 @@
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+
+INTN EFIAPI ShellAppMain(IN UINTN Argc, IN CHAR16 **Argv)
+{
+// SystemTable->ConOut->OutputString(SystemTable->ConOut, L"Hello World!\n");
+ gST->ConOut->OutputString(gST->ConOut, L"Hello again!\n");
+ Print(L"Bye!\n");
+
+ for (UINTN i=Argc; i>0; i--) {
+ Print(L"Arg[%d]=%s\n", Argc-i, Argv[Argc-i]);
+ }
+ return 0;
+}
diff --git a/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf b/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf
new file mode 100644
index 0000000..013bf4e
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf
@@ -0,0 +1,19 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = SimpleShellApp
+ FILE_GUID = 2afd1202-545e-4f8d-b8fb-bc179e84ddc8
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = ShellCEntryLib
+
+[Sources]
+ SimpleShellApp.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
+ UefiLib
+ ShellCEntryLib
+
diff --git a/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.c b/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.c
new file mode 100644
index 0000000..8bdf500
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.c
@@ -0,0 +1,10 @@
+EFI_STATUS
+EFIAPI
+UefiMain (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ return EFI_SUCCESS;
+}
+
diff --git a/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.inf b/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.inf
new file mode 100644
index 0000000..7d4bae2
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/SimplestApp/SimplestApp.inf
@@ -0,0 +1,16 @@
+[Defines]
+ INF_VERSION = 1.25
+ BASE_NAME = SimplestApp
+ FILE_GUID = 4a298956-fbe0-47fb-ae3a-2d5a0a959a26
+ MODULE_TYPE = UEFI_APPLICATION
+ VERSION_STRING = 1.0
+ ENTRY_POINT = UefiMain
+
+[Sources]
+ SimplestApp.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ UefiApplicationEntryPoint
diff --git a/Lesson_15/UefiLessonsPkg/UefiLessonsPkg.dsc b/Lesson_15/UefiLessonsPkg/UefiLessonsPkg.dsc
new file mode 100644
index 0000000..5a3ae1c
--- /dev/null
+++ b/Lesson_15/UefiLessonsPkg/UefiLessonsPkg.dsc
@@ -0,0 +1,36 @@
+[Defines]
+ DSC_SPECIFICATION = 0x0001001C
+ PLATFORM_GUID = 3db7270f-ffac-4139-90a4-0ae68f3f8167
+ PLATFORM_VERSION = 0.01
+ PLATFORM_NAME = UefiLessonsPkg
+ SKUID_IDENTIFIER = DEFAULT
+ SUPPORTED_ARCHITECTURES = X64
+ BUILD_TARGETS = RELEASE
+
+
+[LibraryClasses]
+ UefiApplicationEntryPoint|MdePkg/Library/UefiApplicationEntryPoint/UefiApplicationEntryPoint.inf
+ UefiBootServicesTableLib|MdePkg/Library/UefiBootServicesTableLib/UefiBootServicesTableLib.inf
+ DebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.inf
+ BaseLib|MdePkg/Library/BaseLib/BaseLib.inf
+ PcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.inf
+ BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf
+ RegisterFilterLib|MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.inf
+ PrintLib|MdePkg/Library/BasePrintLib/BasePrintLib.inf
+ DebugPrintErrorLevelLib|MdePkg/Library/BaseDebugPrintErrorLevelLib/BaseDebugPrintErrorLevelLib.inf
+ UefiLib|MdePkg/Library/UefiLib/UefiLib.inf
+ MemoryAllocationLib|MdePkg/Library/UefiMemoryAllocationLib/UefiMemoryAllocationLib.inf
+ DevicePathLib|MdePkg/Library/UefiDevicePathLib/UefiDevicePathLib.inf
+ UefiRuntimeServicesTableLib|MdePkg/Library/UefiRuntimeServicesTableLib/UefiRuntimeServicesTableLib.inf
+ ShellCEntryLib|ShellPkg/Library/UefiShellCEntryLib/UefiShellCEntryLib.inf
+
+[Components]
+ UefiLessonsPkg/SimplestApp/SimplestApp.inf
+ UefiLessonsPkg/HelloWorld/HelloWorld.inf
+ UefiLessonsPkg/ImageHandle/ImageHandle.inf
+ UefiLessonsPkg/ImageInfo/ImageInfo.inf
+ UefiLessonsPkg/MemoryInfo/MemoryInfo.inf
+ UefiLessonsPkg/SimpleShellApp/SimpleShellApp.inf
+ UefiLessonsPkg/ListVariables/ListVariables.inf
+ UefiLessonsPkg/ShowBootVariables/ShowBootVariables.inf
+
diff --git a/README.md b/README.md
index 161d05b..c34a384 100644
--- a/README.md
+++ b/README.md
@@ -17,4 +17,5 @@ Lessons description:
- Lesson 12: `EFI_SHELL_PARAMETERS_PROTOCOL`. Transform our EFI memory map to the Linux kernel style
- Lesson 13: `ShellAppMain` entry point
- Lesson 14: Get all variable names and GUIDs with the `gRT->GetNextVariableName` API
+- Lesson 15: Get and parse boot variables (BootOrder/BootCurrent/BootXXXX) with the `gRT->GetVariable` API