From f4871801a7ec8155684188be22847b5f31e77ca8 Mon Sep 17 00:00:00 2001
From: Rafal Kupiec <belliash@codingworkshop.eu.org>
Date: Mon, 1 Jan 2024 14:18:50 +0100
Subject: [PATCH] Implement BlGetXtLdrProtocol()

---
 sdk/xtdk/blfuncs.h | 23 +++++++++++++++
 sdk/xtdk/xtblapi.h |  1 +
 xtldr2/protocol.c  | 70 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 94 insertions(+)
 create mode 100644 sdk/xtdk/blfuncs.h

diff --git a/sdk/xtdk/blfuncs.h b/sdk/xtdk/blfuncs.h
new file mode 100644
index 0000000..77e0bf1
--- /dev/null
+++ b/sdk/xtdk/blfuncs.h
@@ -0,0 +1,23 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            sdk/xtdk/blfuncs.h
+ * DESCRIPTION:     XT Boot Manager routines
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#ifndef __XTDK_BLFUNCS_H
+#define __XTDK_BLFUNCS_H
+
+#include <xttypes.h>
+#include <xtuefi.h>
+
+
+/* XT BootLoader routines forward references */
+XTCDECL
+EFI_STATUS
+BlGetXtLdrProtocol(IN PEFI_SYSTEM_TABLE SystemTable,
+                   IN EFI_HANDLE ImageHandle,
+                   OUT PXTBL_LOADER_PROTOCOL *ProtocolHandler);
+
+#endif /* __XTDK_BLFUNCS_H */
diff --git a/sdk/xtdk/xtblapi.h b/sdk/xtdk/xtblapi.h
index f58c149..5da87e8 100644
--- a/sdk/xtdk/xtblapi.h
+++ b/sdk/xtdk/xtblapi.h
@@ -45,3 +45,4 @@
 
 /* Boot Manager specific structures */
 #include <bltypes.h>
+#include <blfuncs.h>
diff --git a/xtldr2/protocol.c b/xtldr2/protocol.c
index 503eaa7..13afe52 100644
--- a/xtldr2/protocol.c
+++ b/xtldr2/protocol.c
@@ -52,6 +52,76 @@ BlFindBootProtocol(IN PWCHAR SystemType,
     return STATUS_EFI_NOT_FOUND;
 }
 
+/**
+ * Finds and opens the XT Boot Loader protocol. This routine should be called by module to access XTLDR protocol.
+ *
+ * @param SystemTable
+ *        Provides the EFI system table.
+ *
+ * @param ImageHandle
+ *        Firmware-allocated handle that identifies the image.
+ *
+ * @param ProtocolHandler
+ *        Receives the pointer to the XT Boot Loader protocol.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+EFI_STATUS
+BlGetXtLdrProtocol(IN PEFI_SYSTEM_TABLE SystemTable,
+                   IN EFI_HANDLE ImageHandle,
+                   OUT PXTBL_LOADER_PROTOCOL *ProtocolHandler)
+{
+    EFI_GUID ProtocolGuid = XT_BOOT_LOADER_PROTOCOL_GUID;
+    PEFI_HANDLE Handles = NULL;
+    EFI_STATUS Status;
+    UINT_PTR Count;
+    UINT Index;
+
+    /* Try to locate the handles */
+    Status = SystemTable->BootServices->LocateHandleBuffer(ByProtocol, &ProtocolGuid, NULL, &Count, &Handles);
+    if(Status != STATUS_EFI_SUCCESS)
+    {
+        /* Unable to get handles */
+        return Status;
+    }
+
+    /* Check if any handles returned */
+    if(Count > 0)
+    {
+        /* Iterate through all given handles */
+        for(Index = 0; Index < Count; Index++)
+        {
+            /* Try to open protocol */
+            Status = SystemTable->BootServices->OpenProtocol(Handles[Index], &ProtocolGuid,
+                                                             (PVOID*)ProtocolHandler, ImageHandle, NULL,
+                                                             EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL);
+
+            /* Check if successfully opened the loader protocol */
+            if(Status == STATUS_EFI_SUCCESS)
+            {
+                /* Protocol found and successfully opened */
+                break;
+            }
+        }
+    }
+
+    /* Free handles */
+    SystemTable->BootServices->FreePool(Handles);
+
+    /* Make sure the loaded protocol has been found */
+    if(*ProtocolHandler == NULL)
+    {
+        /* Protocol not found */
+        return STATUS_EFI_NOT_FOUND;
+    }
+
+    /* Return success */
+	return STATUS_EFI_SUCCESS;
+}
+
 /**
  * Loads a specified XTLDR module from disk.
  *