mirror of https://github.com/tongzx/nt5src
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
373 lines
7.1 KiB
373 lines
7.1 KiB
/*++
|
|
|
|
Copyright (c) 1997 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
string.c
|
|
|
|
Abstract:
|
|
|
|
The string stack portion of the un-assembler
|
|
|
|
Author:
|
|
|
|
Stephane Plante
|
|
|
|
Environment:
|
|
|
|
Any
|
|
|
|
Revision History:
|
|
|
|
--*/
|
|
|
|
#include "pch.h"
|
|
|
|
NTSTATUS
|
|
StringStackAllocate(
|
|
OUT PSTRING_STACK *StringStack
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine allocates memory and returns a string stack object
|
|
|
|
Arguments:
|
|
|
|
String Stack - Where to store a pointer to the stack
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
PSTRING_STACK tempStack;
|
|
NTSTATUS status = STATUS_SUCCESS;
|
|
|
|
//
|
|
// Make sure that we have some place to store the stack pointer
|
|
//
|
|
ASSERT( StringStack != NULL );
|
|
|
|
//
|
|
// Allocate a block of memory for the stack
|
|
//
|
|
tempStack = MEMORY_ALLOCATE(
|
|
sizeof(STRING_STACK) + ( STRING_GROWTH_RATE - 1 )
|
|
);
|
|
if (tempStack == NULL) {
|
|
|
|
status = STATUS_INSUFFICIENT_RESOURCES;
|
|
goto StringStackAllocateExit;
|
|
}
|
|
|
|
//
|
|
// Setup the control block of the stack
|
|
//
|
|
tempStack->Signature = (ULONG) STRING_SIGNATURE;
|
|
tempStack->StackSize = STRING_GROWTH_RATE;
|
|
tempStack->TopOfStack = 0;
|
|
|
|
//
|
|
// Zero out the current elements on the stack
|
|
//
|
|
MEMORY_ZERO( tempStack->Stack, STRING_GROWTH_RATE );
|
|
|
|
//
|
|
// Return the stack pointer
|
|
//
|
|
StringStackAllocateExit:
|
|
*StringStack = tempStack;
|
|
return status;
|
|
|
|
}
|
|
|
|
NTSTATUS
|
|
StringStackClear(
|
|
IN OUT PSTRING_STACK *StringStack
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine wipes out the contents of the stack and
|
|
restarts it as if it was new allocated. Saves some from
|
|
freeing and reallocating a stack
|
|
|
|
Arguments:
|
|
|
|
StringStack - Where to find a pointer to the stack
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
PSTRING_STACK localStack;
|
|
|
|
//
|
|
// Make sure that we point to something
|
|
//
|
|
ASSERT( StringStack != NULL && *StringStack != NULL );
|
|
ASSERT( (*StringStack)->Signature == STRING_SIGNATURE );
|
|
|
|
//
|
|
// Zero out the stack
|
|
//
|
|
localStack = *StringStack;
|
|
MEMORY_ZERO( localStack->Stack, localStack->StackSize );
|
|
|
|
//
|
|
// Reset the TOS to the root
|
|
//
|
|
localStack->TopOfStack = 0;
|
|
|
|
//
|
|
// Done
|
|
//
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
NTSTATUS
|
|
StringStackFree(
|
|
IN OUT PSTRING_STACK *StringStack
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine frees the string stack
|
|
|
|
Arguments:
|
|
|
|
StringStack - Where to find a pointer to the stack
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
//
|
|
// Make sure that we point to something
|
|
//
|
|
ASSERT( StringStack != NULL && *StringStack != NULL );
|
|
ASSERT( (*StringStack)->Signature == STRING_SIGNATURE );
|
|
|
|
//
|
|
// Free the stack
|
|
//
|
|
MEMORY_FREE( *StringStack );
|
|
|
|
//
|
|
// Point the stack to nowhere
|
|
//
|
|
*StringStack = NULL;
|
|
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
NTSTATUS
|
|
StringStackPop(
|
|
IN OUT PSTRING_STACK *StringStack,
|
|
IN ULONG NumBytes,
|
|
OUT PUCHAR *String
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine returns a pointer to the requested offset from the end
|
|
of the stack
|
|
|
|
Note: String points to memory that can be freed at any time. It is the
|
|
caller's responsibility to make a copy
|
|
|
|
Arguments:
|
|
|
|
StringStack - Where to find a pointer to the stack
|
|
NumBytes - Number of bytes to pop off
|
|
String - Pointer to the bytes.
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
PSTRING_STACK localStack;
|
|
|
|
//
|
|
// Make sure that we point to something
|
|
//
|
|
ASSERT( StringStack != NULL );
|
|
ASSERT( (*StringStack)->Signature == STRING_SIGNATURE );
|
|
ASSERT( String != NULL );
|
|
|
|
//
|
|
// Is there an item that we can remove from the stack?
|
|
//
|
|
localStack = *StringStack;
|
|
if ( localStack->TopOfStack == 0 ||
|
|
localStack->TopOfStack < NumBytes) {
|
|
|
|
return STATUS_FAIL_CHECK;
|
|
|
|
}
|
|
|
|
//
|
|
// Return a pointer to the requested bytes
|
|
//
|
|
localStack->TopOfStack -= NumBytes;
|
|
*String = &( localStack->Stack[ localStack->TopOfStack ] );
|
|
return STATUS_SUCCESS;
|
|
|
|
}
|
|
|
|
NTSTATUS
|
|
StringStackPush(
|
|
IN OUT PSTRING_STACK *StringStack,
|
|
IN ULONG StringLength,
|
|
IN PUCHAR String
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine obtains a pointer for an object on the top of the stack
|
|
and increments the top to point to something that can be then be used
|
|
again.
|
|
|
|
Arguments:
|
|
|
|
StringStack - Where to find a pointer to the stack
|
|
String - String to push onto stack
|
|
StringLength - How many bytes to push onto the stack
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
PSTRING_STACK localStack;
|
|
PSTRING_STACK tempStack;
|
|
ULONG newSize;
|
|
|
|
//
|
|
// Make sure that we point to something
|
|
//
|
|
ASSERT( StringStack != NULL );
|
|
ASSERT( String != NULL );
|
|
|
|
//
|
|
// Find the stack pointer and make sure that the signature is still
|
|
// valid
|
|
//
|
|
localStack = *StringStack;
|
|
ASSERT( localStack->Signature == STRING_SIGNATURE );
|
|
|
|
//
|
|
// Do we have enough space on the stack?
|
|
//
|
|
if ( localStack->TopOfStack + StringLength > localStack->StackSize ) {
|
|
|
|
//
|
|
// Figure out how many bytes by which to grow the stack and how
|
|
// large the total stack should be
|
|
//
|
|
newSize = sizeof(STRING_STACK) + localStack->StackSize +
|
|
STRING_GROWTH_RATE - 1;
|
|
|
|
//
|
|
// Grow the stack
|
|
//
|
|
tempStack = MEMORY_ALLOCATE( newSize );
|
|
if (tempStack == NULL) {
|
|
|
|
return STATUS_INSUFFICIENT_RESOURCES;
|
|
|
|
}
|
|
|
|
//
|
|
// Empty the new stack and copy the old one to it
|
|
//
|
|
MEMORY_ZERO( tempStack->Stack, newSize - sizeof(STRING_STACK) + 1);
|
|
MEMORY_COPY( tempStack, localStack , newSize - STRING_GROWTH_RATE);
|
|
|
|
//
|
|
// Make sure that the new stack has the correct size
|
|
//
|
|
tempStack->StackSize += STRING_GROWTH_RATE;
|
|
|
|
//
|
|
// Free the old stack
|
|
//
|
|
StringStackFree( StringStack );
|
|
|
|
//
|
|
// Set the stack to point to the new one
|
|
//
|
|
*StringStack = localStack = tempStack;
|
|
|
|
}
|
|
|
|
//
|
|
// Grab a pointer to the part that we will return to the caller
|
|
//
|
|
MEMORY_COPY(
|
|
&(localStack->Stack[ localStack->TopOfStack] ),
|
|
String,
|
|
StringLength
|
|
);
|
|
|
|
//
|
|
// Find the new Top of Stack
|
|
//
|
|
localStack->TopOfStack += StringLength;
|
|
|
|
//
|
|
// Done
|
|
//
|
|
return STATUS_SUCCESS;
|
|
}
|
|
|
|
NTSTATUS
|
|
StringStackRoot(
|
|
IN OUT PSTRING_STACK *StringStack,
|
|
OUT PUCHAR *RootElement
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine returns the topmost stack location that is in current use
|
|
|
|
Arguments:
|
|
|
|
Stack - Where the stack is located
|
|
RootElement - Where to store the pointer to the root stack element
|
|
|
|
Return Value:
|
|
|
|
NTSTATUS
|
|
|
|
--*/
|
|
{
|
|
ASSERT( StringStack != NULL && *StringStack != NULL );
|
|
ASSERT( (*StringStack)->Signature == STRING_SIGNATURE );
|
|
|
|
//
|
|
// Grab the top stack location
|
|
//
|
|
*RootElement = (PUCHAR) (*StringStack)->Stack;
|
|
|
|
//
|
|
// Done
|
|
//
|
|
return STATUS_SUCCESS;
|
|
}
|