Module openj9.dtfj

Package com.ibm.j9ddr.corereaders.tdump.zebedee.dumpreader

Class MutableAddressSpace

java.lang.Object

com.ibm.j9ddr.corereaders.tdump.zebedee.dumpreader.AddressSpace

com.ibm.j9ddr.corereaders.tdump.zebedee.dumpreader.MutableAddressSpace

All Implemented Interfaces:

Emulator.ImageSpace, Serializable

public final class MutableAddressSpace
extends AddressSpace
implements Emulator.ImageSpace

Provides the ability to write as well as read to a copy of the address space. This class is provided for use by the Emulator.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected long	lastMutableBlockAddress	The last mutable block address requested (quick block cache)

Fields declared in class com.ibm.j9ddr.corereaders.tdump.zebedee.dumpreader.AddressSpace

addressMap, asid, dump, lastBlockAddress, lastButOneBlockAddress, ranges, WILD_POINTER

Constructor Summary

Constructors

Constructor	Description
MutableAddressSpace(AddressSpace space)	Creates a new MutableAddressSpace from the given AddressSpace.

Method Summary

Modifier and Type	Method	Description
void	allocPage(long address)	Allocate a page of memory at the given address.
void	free(long ptr)	Free the memory that was previously allocated by malloc.
protected byte[]	getBlockFromCacheOrDisk(long address)	Get the block of bytes for the given address.
long	malloc(int size)	Allocate a chunk of unused memory.
long	rmalloc(int size)
void	writeByte(long address, int value)	Write a byte at the specified address.
void	writeBytes(long address, byte[] array)	Write the contents of the byte array to the specified address.
void	writeInt(long address, int value)	Write an int at the specified address.
void	writeLong(long address, long value)	Write a long at the specified address.
void	writeShort(long address, int value)	Write a short at the specified address.
void	writeWord(long address, long value)	Write a word at the specified address.

Methods declared in class com.ibm.j9ddr.corereaders.tdump.zebedee.dumpreader.AddressSpace

getAddressRanges, getAsid, getBlock, getDump, getImageInputStream, getLowestAddress, getRootAddressSpace, getUnusedAddressRanges, getUserMap, getWordLength, is64bit, isValidAddress, read, read, readAsciiCString, readAsciiString, readAsciiString, readByte, readEbcdicCString, readEbcdicString, readEbcdicString, readInt, readLong, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort, readUtf8String, readWord, readWord, roundToPage, setIs64bit, toString

Methods declared in class java.lang.Object

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

Methods declared in interface com.ibm.j9ddr.corereaders.tdump.zebedee.util.Emulator.ImageSpace

is64bit, readInt, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort

Field Details

lastMutableBlockAddress

protected long lastMutableBlockAddress

The last mutable block address requested (quick block cache)

Constructor Details

MutableAddressSpace

public MutableAddressSpace(AddressSpace space)

Creates a new MutableAddressSpace from the given AddressSpace. Updates to this "forked" copy will not be reflected in the parent AddressSpace.

Parameters:

AddressSpace - the address space we read from

Method Details

getBlockFromCacheOrDisk

protected byte[] getBlockFromCacheOrDisk(long address)
                                  throws IOException

Get the block of bytes for the given address. We look first in our own cache and if its not there call the superclass method.

Overrides:

getBlockFromCacheOrDisk in class AddressSpace

Throws:

IOException

writeBytes

public void writeBytes(long address,
 byte[] array)
                throws IOException

Write the contents of the byte array to the specified address.

Throws:

IOException - if the given address (of offset from there) is not present in this address space

writeWord

public void writeWord(long address,
 long value)
               throws IOException

Write a word at the specified address. A word is either 32 or 64 bits depending on the machine context.

Throws:

IOException

writeByte

public void writeByte(long address,
 int value)
               throws IOException

Write a byte at the specified address.

Specified by:

writeByte in interface Emulator.ImageSpace

Throws:

IOException - if the given address is not present in this address space

writeShort

public void writeShort(long address,
 int value)
                throws IOException

Write a short at the specified address.

Specified by:

writeShort in interface Emulator.ImageSpace

Throws:

IOException - if the given address is not present in this address space

writeInt

public void writeInt(long address,
 int value)
              throws IOException

Write an int at the specified address.

Specified by:

writeInt in interface Emulator.ImageSpace

Throws:

IOException - if the given address is not present in this address space

writeLong

public void writeLong(long address,
 long value)
               throws IOException

Write a long at the specified address.

Specified by:

writeLong in interface Emulator.ImageSpace

Throws:

IOException - if the given address is not present in this address space

malloc

public long malloc(int size)
            throws IOException

Allocate a chunk of unused memory. This searches the known address ranges and tries to find an unallocated area of the given size. If successful, this area effectively becomes part of this ImageSpace and may be read and written to as normal. This method is used by users of the Emulator for things like allocating stack, arguments etc.

Specified by:

malloc in interface Emulator.ImageSpace

Returns:

the address of the allocated memory

Throws:

IOException

rmalloc

public long rmalloc(int size)
             throws IOException

Throws:

IOException

free

public void free(long ptr)
          throws IOException

Free the memory that was previously allocated by malloc.

Throws:

IOException

allocPage

public void allocPage(long address)
               throws IOException

Allocate a page of memory at the given address. The address must not already be in use. A page is 4096 bytes in length. Address must be on a page boundary.

Throws:

IOException