From dd406cf5b5b58ce458f7b9f963233e428aca7c74 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Wed, 9 Mar 2022 15:30:07 -0500
Subject: [PATCH] Show addresses of some EFI structures

---
 main.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/main.c b/main.c
index 60802ab..42b5b43 100644
--- a/main.c
+++ b/main.c
@@ -22,6 +22,22 @@ static void write_uint(uint32_t n)
     write_string(&s[11u - i]);
 }
 
+static void write_ptr(size_t n)
+{
+    CHAR16 hexchars[] = L"0123456789ABCDEF";
+    CHAR16 s[20] = {0};
+    size_t s_i = 0u;
+    for (size_t i = 0u; i < 16u; i++)
+    {
+        if ((i != 0u) && ((i % 4u) == 0u))
+        {
+            s[s_i++] = L'_';
+        }
+        s[s_i++] = hexchars[(n >> (60u - 4u * i)) & 0xFu];
+    }
+    write_string(s);
+}
+
 static void check_handle(EFI_HANDLE handle)
 {
     EFI_HANDLE interface = NULL;
@@ -42,6 +58,10 @@ static void check_handle(EFI_HANDLE handle)
         return;
     }
 
+    write_string(L"interface is at ");
+    write_ptr((size_t)interface);
+    write_string(L"\r\n");
+
     EFI_GRAPHICS_OUTPUT_PROTOCOL * gop = (EFI_GRAPHICS_OUTPUT_PROTOCOL *)interface;
 }
 
@@ -59,6 +79,10 @@ efi_main(EFI_HANDLE image_handle, EFI_SYSTEM_TABLE * system_table)
     if (EFI_ERROR(status))
         return status;
 
+    write_string(L"system_table is at ");
+    write_ptr((size_t)system_table);
+    write_string(L"\r\n");
+
     EFI_HANDLE buffer[10];
     UINTN buffer_size = sizeof(buffer);
     status = system_table->BootServices->LocateHandle(ByProtocol,
@@ -67,7 +91,7 @@ efi_main(EFI_HANDLE image_handle, EFI_SYSTEM_TABLE * system_table)
             &buffer_size,
             buffer);
     buffer_size /= sizeof(EFI_HANDLE);
-    write_string(L"status = ");
+    write_string(L"LocateHandle status = ");
     write_uint(status);
     write_string(L", num entries = ");
     write_uint(buffer_size);