diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/ia32/SwitchStack.c')
-rw-r--r-- | MdePkg/Library/BaseLib/ia32/SwitchStack.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/ia32/SwitchStack.c b/MdePkg/Library/BaseLib/ia32/SwitchStack.c new file mode 100644 index 0000000000..77800e35dd --- /dev/null +++ b/MdePkg/Library/BaseLib/ia32/SwitchStack.c @@ -0,0 +1,57 @@ +/** @file
+ SwitchStack() function for IA-32.
+
+ Copyright (c) 2006, Intel Corporation<BR>
+ All rights reserved. This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+ Module Name: SwitchStack.c
+
+**/
+
+/**
+ Transfers control to a function starting with a new stack.
+
+ Transfers control to the function specified by EntryPoint using the new stack
+ specified by NewStack and passing in the parameters specified by Context1 and
+ Context2. Context1 and Context2 are optional and may be NULL. The function
+ EntryPoint must never return.
+
+ If EntryPoint is NULL, then ASSERT().
+ If NewStack is NULL, then ASSERT().
+
+ @param EntryPoint A pointer to function to call with the new stack.
+ @param Context1 A pointer to the context to pass into the EntryPoint
+ function.
+ @param Context2 A pointer to the context to pass into the EntryPoint
+ function.
+ @param NewStack A pointer to the new stack to use for the EntryPoint
+ function.
+
+**/
+VOID
+EFIAPI
+SwitchStack (
+ IN SWITCH_STACK_ENTRY_POINT EntryPoint,
+ IN VOID *Context1,
+ IN VOID *Context2,
+ IN VOID *NewStack
+ )
+{
+ BASE_LIBRARY_JUMP_BUFFER JumpBuffer;
+
+ ASSERT (EntryPoint != NULL && NewStack != NULL);
+
+ JumpBuffer.Eip = (UINTN)EntryPoint;
+ JumpBuffer.Esp = (UINTN)NewStack - sizeof (VOID*);
+ JumpBuffer.Esp -= sizeof (Context1) + sizeof (Context2);
+ ((VOID**)JumpBuffer.Esp)[1] = Context1;
+ ((VOID**)JumpBuffer.Esp)[2] = Context2;
+
+ LongJump (&JumpBuffer, (UINTN)-1);
+}
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