Package ghidra.pcode.memstate

Class MemoryPage

java.lang.Object

ghidra.pcode.memstate.MemoryPage

public class MemoryPage
extends java.lang.Object

MemoryPage is allows the contents/data of a memory page to be maintained along with an initializedMask. Each bit within the initializedMask corresponds to a data byte within the page. A null mask indicates that all data within the page is initialized. A one-bit within the mask indicates that the corresponding data byte is initialized.

Field Summary

Fields

Modifier and Type	Field	Description
byte[]	data

Constructor Summary

Constructors

Constructor	Description
MemoryPage(byte[] bytes)	Construct a memory page with an existing data bytes buffer
MemoryPage(int pageSize)	Construct a new fully initialized page containing all zero (0) byte data.

Method Summary

Modifier and Type	Method	Description
static int	getInitializedByteCount(byte[] initializedMask, int pageOffset, int size)	Determine how many leading bytes of a specified page region is marked as initialized.
int	getInitializedByteCount(int pageOffset, int size)	Get number of leading bytes within page range which have been initialized.
byte[]	getInitializedMask()
static byte[]	getInitializedMask(int pageSize, boolean initialized)	Generate an initialized mask for the specified page size
static byte[]	getInitializedMask(int pageSize, int offset, int size, boolean initialized)	Generate an initialized mask for the specified page size.
void	setInitialized()	Mark entire page as uninitialized
static void	setInitialized(byte[] initializedMask, int pageOffset, int size)	Mark specified page region as initialized.
void	setInitialized(int pageOffset, int size)	Mark specified page region as initialized.
void	setInitialized(int pageOffset, int size, byte[] maskUpdate)	Update initialization mask
void	setUninitialized()	Mark entire page as uninitialized
static void	setUninitialized(byte[] initializedMask, int pageOffset, int size)	Mark specified page region as uninitialized.
void	setUninitialized(int pageOffset, int size)	Mark specified page region as uninitialized.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

data

public final byte[] data

Constructor Detail

MemoryPage

public MemoryPage(int pageSize)

Construct a new fully initialized page containing all zero (0) byte data.

MemoryPage

public MemoryPage(byte[] bytes)

Construct a memory page with an existing data bytes buffer

Parameters:

bytes - buffer

Method Detail

getInitializedMask

public byte[] getInitializedMask()

setUninitialized

public void setUninitialized()

Mark entire page as uninitialized

setInitialized

public void setInitialized()

Mark entire page as uninitialized

setInitialized

public void setInitialized(int pageOffset,
                           int size,
                           byte[] maskUpdate)

Update initialization mask

Parameters:

pageOffset -

size -

maskUpdate -

setInitialized

public void setInitialized(int pageOffset,
                           int size)

Mark specified page region as initialized.

Parameters:

pageOffset -

size -

setUninitialized

public void setUninitialized(int pageOffset,
                             int size)

Mark specified page region as uninitialized.

Parameters:

pageOffset -

size -

getInitializedByteCount

public int getInitializedByteCount(int pageOffset,
                                   int size)

Get number of leading bytes within page range which have been initialized.

Parameters:

pageOffset -

size -

Returns:

number of leading bytes within page range which have been initialized.

getInitializedMask

public static byte[] getInitializedMask(int pageSize,
                                        boolean initialized)

Generate an initialized mask for the specified page size

Parameters:

pageSize -

initialized -

Returns:

getInitializedMask

public static byte[] getInitializedMask(int pageSize,
                                        int offset,
                                        int size,
                                        boolean initialized)

Generate an initialized mask for the specified page size. The region is identified by offset and size. The remaining portions of the mask will be set based upon !initialized.

Parameters:

pageSize -

offset -

size -

initialized -

Returns:

setInitialized

public static void setInitialized(byte[] initializedMask,
                                  int pageOffset,
                                  int size)

Mark specified page region as initialized.

Parameters:

initializedMask -

pageOffset -

size -

setUninitialized

public static void setUninitialized(byte[] initializedMask,
                                    int pageOffset,
                                    int size)

Mark specified page region as uninitialized.

Parameters:

initializedMask -

pageOffset -

size -

getInitializedByteCount

public static int getInitializedByteCount(byte[] initializedMask,
                                          int pageOffset,
                                          int size)

Determine how many leading bytes of a specified page region is marked as initialized. Valid page region defined by pageOffset and size is assumed.

Parameters:

initializedMask -

pageOffset -

size -

Returns:

number of leading bytes at pageOffset (upto size) are initialized.