diff options
Diffstat (limited to 'EmulatorPkg/Unix/Host/Ia32/SwitchStack.c')
-rw-r--r-- | EmulatorPkg/Unix/Host/Ia32/SwitchStack.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/EmulatorPkg/Unix/Host/Ia32/SwitchStack.c b/EmulatorPkg/Unix/Host/Ia32/SwitchStack.c new file mode 100644 index 0000000000..c75073ac2e --- /dev/null +++ b/EmulatorPkg/Unix/Host/Ia32/SwitchStack.c @@ -0,0 +1,74 @@ +/*++ + +Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR> +Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR> +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. + + +--*/ + +#include "SecMain.h" + + +/** + 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 +PeiSwitchStacks ( + IN SWITCH_STACK_ENTRY_POINT EntryPoint, + IN VOID *Context1, OPTIONAL + IN VOID *Context2, OPTIONAL + IN VOID *NewStack + ) +{ + BASE_LIBRARY_JUMP_BUFFER JumpBuffer; + + ASSERT (EntryPoint != NULL); + ASSERT (NewStack != NULL); + + // + // Stack should be aligned with CPU_STACK_ALIGNMENT + // + ASSERT (((UINTN)NewStack & (CPU_STACK_ALIGNMENT - 1)) == 0); + + 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); + + + // + // PeiSwitchStacks () will never return + // + ASSERT (FALSE); +} + + + |