OverlaySpace Class Reference

An overlay space. More...

#include <space.hh>

Inheritance diagram for OverlaySpace:

Public Member Functions
	OverlaySpace (AddrSpaceManager *m, const Translate *t)
	Constructor. More...
AddrSpace *	getBaseSpace (void) const
	Get the address space being overlayed. More...
virtual void	saveXml (ostream &s) const
	Write the details of this space as XML. More...
virtual void	restoreXml (const Element *el)
	Recover the details of this space from XML. More...
Public Member Functions inherited from AddrSpace
	AddrSpace (AddrSpaceManager *m, const Translate *t, spacetype tp, const string &nm, uint4 size, uint4 ws, int4 ind, uint4 fl, int4 dl)
	AddrSpace (AddrSpaceManager *m, const Translate *t, spacetype tp)
	For use with restoreXml. More...
virtual	~AddrSpace (void)
	The address space destructor.
const string &	getName (void) const
	Get the name. More...
AddrSpaceManager *	getManager (void) const
	Get the space manager. More...
const Translate *	getTrans (void) const
	Get the processor translator. More...
spacetype	getType (void) const
	Get the type of space. More...
int4	getDelay (void) const
	Get number of heritage passes being delayed. More...
int4	getDeadcodeDelay (void) const
	Get number of passes before deadcode removal is allowed. More...
int4	getIndex (void) const
	Get the integer identifier. More...
uint4	getWordSize (void) const
	Get the addressable unit size. More...
uint4	getAddrSize (void) const
	Get the size of the space. More...
uintb	getHighest (void) const
	Get the highest byte-scaled address. More...
uintb	wrapOffset (uintb off) const
	Wrap -off- to the offset that fits into this space. More...
char	getShortcut (void) const
	Get the shortcut character. More...
bool	contain (AddrSpace *id2) const
	Determine if this space contains another. More...
bool	isHeritaged (void) const
	Return true if dataflow has been traced. More...
bool	doesDeadcode (void) const
	Return true if dead code analysis should be done on this space. More...
bool	hasPhysical (void) const
	Return true if data is physically stored in this. More...
bool	isBigEndian (void) const
	Return true if values in this space are big endian. More...
bool	isReverseJustified (void) const
	Return true if alignment justification does not match endianness. More...
bool	isOverlay (void) const
	Return true if this is an overlay space.
bool	isOverlayBase (void) const
	Return true if other spaces overlay this space.
bool	isTruncated (void) const
	Return true if this space is truncated from its original size. More...
uintm	data2Uintm (const uint1 *ptr, int4 size) const
	Convert a sequence of bytes into an integer value. More...
void	printOffset (ostream &s, uintb offset) const
	Write an address offset to a stream. More...
virtual int4	numSpacebase (void) const
	Number of base registers associated with this space. More...
virtual const VarnodeData &	getSpacebase (int4 i) const
	Get a base register that creates this virtual space. More...
virtual const VarnodeData &	getSpacebaseFull (int4 i) const
	Return original spacebase register before truncation. More...
virtual bool	stackGrowsNegative (void) const
	Return true if a stack in this space grows negative. More...
virtual AddrSpace *	getContain (void) const
	Return this space's containing space (if any) More...
virtual void	saveXmlAttributes (ostream &s, uintb offset) const
	Save an address as XML. More...
virtual void	saveXmlAttributes (ostream &s, uintb offset, int4 size) const
	Save an address and size as XML. More...
virtual uintb	restoreXmlAttributes (const Element *el, uint4 &size) const
	Recover an offset and size. More...
virtual void	printRaw (ostream &s, uintb offset) const
	Write an address in this space to a stream. More...
virtual uintb	read (const string &s, int4 &size) const
	Read in an address (and possible size) from a string. More...

Private Attributes
AddrSpace *	baseSpace
	Space being overlayed.

Additional Inherited Members
Public Types inherited from AddrSpace
enum	{   big_endian = 1, heritaged = 2, does_deadcode = 4, programspecific = 8,   reverse_justification = 16, overlay = 32, overlaybase = 64, truncated = 128,   hasphysical = 256 }
Static Public Member Functions inherited from AddrSpace
static uintb	addressToByte (uintb val, uint4 ws)
	Scale from addressable units to byte units. More...
static uintb	byteToAddress (uintb val, uint4 ws)
	Scale from byte units to addressable units. More...
static int4	addressToByteInt (int4 val, uint4 ws)
	Scale int4 from addressable units to byte units. More...
static int4	byteToAddressInt (int4 val, uint4 ws)
	Scale int4 from byte units to addressable units. More...
Protected Member Functions inherited from AddrSpace
void	calcScaleMask (void)
	Calculate scale and mask. More...
void	assignShortcut (void)
	Assign a shortcut character to the space. More...
void	setFlags (uint4 fl)
	Set a cached attribute. More...
void	clearFlags (uint4 fl)
	Clear a cached attribute. More...
void	saveBasicAttributes (ostream &s) const
	Write the XML attributes of this space. More...
void	truncateSpace (uint4 newsize)
Protected Attributes inherited from AddrSpace
string	name
	Name of this space.
uint4	addressSize
	Size of an address into this space in bytes.
uint4	wordsize
	Size of unit being addressed (1=byte)
int4	index
	An integer identifier for the space.
int4	delay
	Delay in heritaging this space.
int4	deadcodedelay
	Delay before deadcode removal is allowed on this space.

Detailed Description

An overlay space.

A different code and data layout that occupies the same memory as another address space. Some compilers use this concept to increase the logical size of a program without increasing its physical memory requirements. An overlay space allows the same physical location to contain different code and be labeled with different symbols, depending on context. From the point of view of reverse engineering, the different code and symbols are viewed as a logically distinct space.

Constructor & Destructor Documentation

OverlaySpace()

OverlaySpace::OverlaySpace	(	AddrSpaceManager *	m,
		const Translate *	t
	)

Constructor.

Parameters

m	is the address space manager
t	is the processor translator

References baseSpace, AddrSpace::overlay, and AddrSpace::setFlags().

Member Function Documentation

getBaseSpace()

AddrSpace * OverlaySpace::getBaseSpace

(

void

)

const

Get the address space being overlayed.

Returns

the base address space

References baseSpace.

Referenced by AddrSpaceManager::insertSpace(), and Architecture::parseGlobal().

restoreXml()

void OverlaySpace::restoreXml ( const Element *  el )

virtual

Recover the details of this space from XML.

Walk a parsed XML tag and recover all the properties defining this space. The processor translator, trans, and the type must already be filled in.

Parameters

el	is the parsed XML tag

Reimplemented from AddrSpace.

References AddrSpace::addressSize, AddrSpace::assignShortcut(), baseSpace, AddrSpace::big_endian, AddrSpace::calcScaleMask(), AddrSpace::deadcodedelay, AddrSpace::delay, AddrSpace::getAddrSize(), AddrSpace::getDeadcodeDelay(), AddrSpace::getDelay(), AddrSpace::getManager(), AddrSpaceManager::getSpaceByName(), AddrSpace::getWordSize(), AddrSpace::hasphysical, AddrSpace::hasPhysical(), AddrSpace::index, AddrSpace::isBigEndian(), AddrSpace::name, AddrSpace::setFlags(), and AddrSpace::wordsize.

saveXml()

void OverlaySpace::saveXml ( ostream &  s ) const

virtual

Write the details of this space as XML.

Write a tag fully describing the details of this space suitable for later recovery via restoreXml.

Parameters

s	is the stream being written

Reimplemented from AddrSpace.

References baseSpace, AddrSpace::getName(), AddrSpace::index, and AddrSpace::name.

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The documentation for this class was generated from the following files:

• space.hh
• space.cc