PosixSubsystem Class Reference

#include <PosixSubsystem.h>

Inheritance diagram for PosixSubsystem:

Collaboration diagram for PosixSubsystem:

Classes
struct	AlternateSignalStack
class	PosixSyncObject
class	PosixThread
struct	PosixThreadKey
struct	SignalHandler

Public Types
enum	Abi { PosixAbi = 0, LinuxAbi = 1 }
Public Types inherited from Subsystem
enum	SubsystemType { Posix = 0, Native = 1, None = 255 }
enum	KillReason { Interrupted = 0, Terminated = 1, Unknown = 255 }
enum	ExceptionType {   InvalidOpcode = 0, PageFault = 1, GeneralProtectionFault = 2, DivideByZero = 3,   FpuError = 4, SpecialFpuError = 5, TerminalInput = 6, TerminalOutput = 7,   Continue = 8, Stop = 9, Interrupt = 10, Quit = 11,   Child = 12, Pipe = 13, Other = 255 }

Public Member Functions
	PosixSubsystem ()
	PosixSubsystem (PosixSubsystem &s)
	PosixSubsystem (SubsystemType type)
virtual	~PosixSubsystem ()
virtual void	acquire ()
	Acquire full mutual exclusion for all Subsystem resources. More...
virtual void	release ()
virtual bool	kill (KillReason killReason, Thread *pThread)
virtual void	threadException (Thread *pThread, ExceptionType eType)
virtual void	sendSignal (Thread *pThread, int signal, bool yield=true)
AlternateSignalStack &	getAlternateSignalStack ()
void	setAlternateSignalStack (AlternateSignalStack &s)
void	setSignalHandler (size_t sig, SignalHandler *handler)
SignalHandler *	getSignalHandler (size_t sig)
void	exit (int code) NORETURN
bool	copyDescriptors (PosixSubsystem *pSubsystem)
size_t	getFd ()
void	allocateFd (size_t fdNum)
void	freeFd (size_t fdNum)
void	freeMultipleFds (bool bOnlyCloExec=false, size_t iFirst=0, size_t iLast=-1)
FileDescriptor *	getFileDescriptor (size_t fd)
void	addFileDescriptor (size_t fd, FileDescriptor *pFd)
PosixSyncObject *	getSyncObject (size_t n)
void	insertSyncObject (size_t n, PosixSyncObject *sem)
void	removeSyncObject (size_t n)
PosixThread *	getThread (size_t n)
void	insertThread (size_t n, PosixThread *thread)
void	removeThread (size_t n)
Semaphore *	getThreadWaiter (void *n)
void *	insertThreadWaiter (Semaphore *waiter)
void	removeThreadWaiter (void *n)
bool	checkAccess (FileDescriptor *pFileDescriptor, bool bRead, bool bWrite, bool bExecute) const
virtual bool	invoke (const char *name, Vector< String > &argv, Vector< String > &env)
virtual bool	invoke (const char *name, Vector< String > &argv, Vector< String > &env, SyscallState &state)
virtual bool	invoke (File *originalFile, const String &originalName, Vector< String > &argv, Vector< String > &env)
virtual bool	invoke (File *originalFile, const String &originalName, Vector< String > &argv, Vector< String > &env, SyscallState &state)
virtual File *	findFile (const String &path, File *workingDir)
Abi	getAbi () const
void	setAbi (Abi which)
Public Member Functions inherited from Subsystem
	Subsystem ()
	Subsystem (const Subsystem &s)
	Subsystem (SubsystemType type)
virtual	~Subsystem ()
SubsystemType	getType ()
virtual void	setProcess (Process *p)

Static Public Member Functions
static bool	checkAddress (uintptr_t addr, size_t extent, size_t flags)

Static Public Attributes
static const size_t	SafeRegion = 0x0
static const size_t	SafeRead = 0x1
static const size_t	SafeWrite = 0x2

Private Member Functions
virtual void	threadRemoved (Thread *pThread)
bool	loadElf (File *pFile, uintptr_t mappedAddress, uintptr_t &newAddress, uintptr_t &finalAddress, bool &relocated)
bool	invoke (const char *name, Vector< String > &argv, Vector< String > &env, SyscallState *state)
bool	invoke (File *originalFile, const String &originalName, Vector< String > &argv, Vector< String > &env, SyscallState *state)
bool	parseShebang (File *pFile, File *&outFile, Vector< String > &argv)

Private Attributes
Tree< size_t, SignalHandler * >	m_SignalHandlers
UnlikelyLock	m_SignalHandlersLock
Tree< size_t, FileDescriptor * >	m_FdMap
size_t	m_NextFd
UnlikelyLock	m_FdLock
ExtensibleBitmap	m_FdBitmap
size_t	m_LastFd
int	m_FreeCount
AlternateSignalStack	m_AltSigStack
Tree< size_t, PosixSyncObject * >	m_SyncObjects
Tree< size_t, PosixThread * >	m_Threads
Tree< void *, Semaphore * >	m_ThreadWaiters
size_t	m_NextThreadWaiter
Abi	m_Abi
bool	m_bAcquired
Thread *	m_pAcquiredThread
Spinlock	m_Lock
LruCache< String, File * >	m_FindFileCache
	LRU cache for file lookups. Many usage patterns involve something like a stat() immediately followed by an open() or other similar system call. Rather than have both fully complete a filesystem traversal, we can cache the result and save time.
Filesystem *	m_pRootFs = nullptr

Additional Inherited Members
Protected Attributes inherited from Subsystem
SubsystemType	m_Type
Process *	m_pProcess

Detailed Description

Defines the compatibility layer for the POSIX Subsystem

Definition at line 105 of file PosixSubsystem.h.

Member Enumeration Documentation

enum PosixSubsystem::Abi

ABI mode.

Definition at line 114 of file PosixSubsystem.h.

Constructor & Destructor Documentation

PosixSubsystem::PosixSubsystem ( )

inline

Default constructor

Definition at line 121 of file PosixSubsystem.h.

PosixSubsystem::PosixSubsystem

(

PosixSubsystem &

s

)

Copy constructor

Definition at line 112 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), Tree< K, E >::begin(), Tree< K, E >::end(), UnlikelyLock::enter(), Tree< K, E >::insert(), UnlikelyLock::leave(), m_SignalHandlers, m_SignalHandlersLock, m_ThreadWaiters, and UnlikelyLock::release().

PosixSubsystem::PosixSubsystem ( SubsystemType  type )

inline

Parameterised constructor

Definition at line 134 of file PosixSubsystem.h.

PosixSubsystem::~PosixSubsystem ( )

virtual

Default destructor

Todo:

Call the destructor (need a way to call into userspace and return back here)

Definition at line 153 of file PosixSubsystem.cc.

References Spinlock::acquire(), acquire(), assert, Tree< K, E >::begin(), Tree< K, E >::clear(), Tree< K, E >::end(), freeMultipleFds(), Process::getAddressSpace(), Semaphore::getValue(), Processor::information(), MemoryMapManager::instance(), m_FreeCount, m_SignalHandlers, m_SyncObjects, PosixSubsystem::PosixThread::m_ThreadData, m_Threads, m_ThreadWaiters, Spinlock::release(), Semaphore::release(), release(), MemoryMapManager::releaseLock(), Processor::switchAddressSpace(), Semaphore::tryAcquire(), MemoryMapManager::unmapAllUnlocked(), and WARNING.

Member Function Documentation

void PosixSubsystem::acquire ( )

virtual

Acquire full mutual exclusion for all Subsystem resources.

It is sometimes necessary to perform an operation that would require the entire Subsystem to be owned by a specific thread. For example, Subsystem termination often requires all other threads to exit the Subsystem's critical sections before it can complete.

This call allows that thread to acquire that mutual exclusion.

Reimplemented from Subsystem.

Definition at line 278 of file PosixSubsystem.cc.

References Spinlock::acquire(), UnlikelyLock::acquire(), Processor::information(), m_bAcquired, m_FdLock, m_Lock, m_pAcquiredThread, m_SignalHandlersLock, and Spinlock::release().

Referenced by ~PosixSubsystem().

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void PosixSubsystem::addFileDescriptor	(	size_t	fd,
		FileDescriptor *	pFd
	)

Inserts a file descriptor

Todo:

this is possibly racy

Definition at line 946 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), allocateFd(), freeFd(), Tree< K, E >::insert(), m_FdLock, m_FdMap, and UnlikelyLock::release().

void PosixSubsystem::allocateFd

(

size_t

fdNum

)

Sets the given file descriptor as "in use".

Definition at line 781 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), m_FdBitmap, m_FdLock, m_NextFd, UnlikelyLock::release(), and ExtensibleBitmap::set().

Referenced by addFileDescriptor().

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bool PosixSubsystem::checkAddress ( uintptr_t  addr, size_t  extent, size_t  flags  )

static

Check whether a given region of memory is safe for the given operations.

This is important to do as we can get pointers from anywhere in the POSIX subsystem, and making sure they are sane and safe is crucial.

Todo:

This has a security flaw in that between the check and the use of the actual pointer, the pointer can become invalid due to other threads being active in the process. It may be worth having a Process-wide UnlikelyLock which has the mmap family of functions, sbrk, etc... as writers, and all other syscalls as readers. This would ensure a multithreaded application is not able to crash the kernel.

Definition at line 317 of file PosixSubsystem.cc.

References VirtualAddressSpace::CopyOnWrite, Dec, VirtualAddressSpace::getKernelStart(), VirtualAddressSpace::getMapping(), PhysicalMemoryManager::getPageSize(), VirtualAddressSpace::getUserStart(), Hex, Processor::information(), MemoryMapManager::instance(), VirtualAddressSpace::isMapped(), and VirtualAddressSpace::Write.

Referenced by WaitCleanup::terminated().

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bool PosixSubsystem::copyDescriptors

(

PosixSubsystem *

pSubsystem

)

Copies file descriptors from another subsystem

Definition at line 819 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), assert, Tree< K, E >::begin(), Tree< K, E >::end(), freeMultipleFds(), Tree< K, E >::insert(), m_FdBitmap, m_FdLock, m_FdMap, m_NextFd, UnlikelyLock::release(), and ExtensibleBitmap::set().

void PosixSubsystem::exit ( int  code )

virtual

Need to exit this process.

Note

If we're at state level one, we're potentially running as a thread that has had an event sent to it from another process. If this is changed to > 0, it is impossible to return to a shell when a segfault occurs in an app.

Implements Subsystem.

Definition at line 399 of file PosixSubsystem.cc.

References List< T, nodePoolSize >::begin(), Dec, List< T, nodePoolSize >::end(), List< T, nodePoolSize >::erase(), Thread::Exit, FATAL, freeMultipleFds(), Process::getExitStatus(), Process::getId(), Process::getParent(), Thread::getParent(), Thread::getStateLevel(), Process::getThread(), Process::getType(), Processor::information(), MemoryMapManager::instance(), Process::kill(), ProcessGroup::Leader, PosixProcess::Leader, m_FindFileCache, PosixProcess::Member, ProcessGroup::Members, NOTICE, Thread::ReleaseBlockingThread, Process::setExitStatus(), Processor::setInterrupts(), Thread::setUnwindState(), List< T, nodePoolSize >::size(), Subsystem::threadException(), Thread::unexpectedExit(), and MemoryMapManager::unmapAll().

Referenced by WaitCleanup::terminated().

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File * PosixSubsystem::findFile ( const String &  path, File *  workingDir  )

virtual

Finds a file, performing any subsystem-specific logic as needed.

Implements Subsystem.

Definition at line 1169 of file PosixSubsystem.cc.

References assert, VFS::find(), LruCache< K, T, Slots >::get(), getAbi(), Process::getCwd(), Filesystem::getRoot(), VFS::instance(), VFS::lookupFilesystem(), m_FindFileCache, m_pRootFs, and LruCache< K, T, Slots >::store().

void PosixSubsystem::freeFd

(

size_t

fdNum

)

Sets the given file descriptor as "available" and deletes the FileDescriptor linked to it.

Definition at line 796 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), ExtensibleBitmap::clear(), Tree< K, E >::lookup(), m_FdBitmap, m_FdLock, m_FdMap, m_LastFd, UnlikelyLock::release(), and Tree< K, E >::remove().

Referenced by addFileDescriptor().

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void PosixSubsystem::freeMultipleFds	(	bool	bOnlyCloExec = false,
		size_t	iFirst = 0,
		size_t	iLast = -1
	)

Frees a range of descriptors (or only those marked FD_CLOEXEC)

Definition at line 860 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), assert, List< T, nodePoolSize >::begin(), Tree< K, E >::begin(), ExtensibleBitmap::clear(), Tree< K, E >::clear(), List< T, nodePoolSize >::end(), Tree< K, E >::end(), FileDescriptor::fdflags, m_FdBitmap, m_FdLock, m_FdMap, m_LastFd, List< T, nodePoolSize >::pushBack(), UnlikelyLock::release(), and Tree< K, E >::remove().

Referenced by copyDescriptors(), exit(), invoke(), and ~PosixSubsystem().

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Abi PosixSubsystem::getAbi ( ) const

inline

Retrieves the currently-active ABI for the subsystem.

Definition at line 510 of file PosixSubsystem.h.

Referenced by findFile(), and WaitCleanup::terminated().

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AlternateSignalStack& PosixSubsystem::getAlternateSignalStack ( )

inline

Grabs the alternate signal stack

Definition at line 203 of file PosixSubsystem.h.

size_t PosixSubsystem::getFd

(

)

Returns the first available file descriptor.

Note: POSIX requires open()/accept()/etc to be safe during a signal handler, which requires us to not allow signals during these file descriptor calls. They cannot re-enter as they take process-specific locks.

Definition at line 753 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), m_FdBitmap, m_FdLock, m_LastFd, m_NextFd, UnlikelyLock::release(), ExtensibleBitmap::set(), and ExtensibleBitmap::test().

FileDescriptor * PosixSubsystem::getFileDescriptor

(

size_t

fd

)

Gets a pointer to a FileDescriptor object from an fd number

Definition at line 931 of file PosixSubsystem.cc.

References UnlikelyLock::enter(), UnlikelyLock::leave(), Tree< K, E >::lookup(), m_FdLock, and m_FdMap.

SignalHandler* PosixSubsystem::getSignalHandler ( size_t  sig )

inline

Gets a signal handler

Definition at line 276 of file PosixSubsystem.h.

References NORETURN.

Referenced by kill(), and sendSignal().

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PosixSyncObject* PosixSubsystem::getSyncObject ( size_t  n )

inline

Gets a synchronisation object given a descriptor

Definition at line 334 of file PosixSubsystem.h.

PosixThread* PosixSubsystem::getThread ( size_t  n )

inline

Gets a thread given a descriptor

Definition at line 439 of file PosixSubsystem.h.

Semaphore* PosixSubsystem::getThreadWaiter ( void *  n )

inline

Gets a thread waiter object given a descriptor

Definition at line 462 of file PosixSubsystem.h.

void PosixSubsystem::insertSyncObject ( size_t  n, PosixSyncObject *  sem  )

inline

Inserts a synchronisation object given a descriptor

Definition at line 340 of file PosixSubsystem.h.

void PosixSubsystem::insertThread ( size_t  n, PosixThread *  thread  )

inline

Inserts a thread given a descriptor and a Thread

Todo:

It might be safe to delete the pointer... We'll see.

Definition at line 445 of file PosixSubsystem.h.

void* PosixSubsystem::insertThreadWaiter ( Semaphore *  waiter )

inline

Inserts a thread waiter object, returns a descriptor

Definition at line 468 of file PosixSubsystem.h.

bool PosixSubsystem::invoke ( const char *  name, Vector< String > &  argv, Vector< String > &  env  )

virtual

Invokes the given command (thread mechanism).

Implements Subsystem.

Definition at line 1231 of file PosixSubsystem.cc.

Referenced by invoke(), and parseShebang().

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bool PosixSubsystem::invoke ( const char *  name, Vector< String > &  argv, Vector< String > &  env, SyscallState &  state  )

virtual

Invokes the given command (SyscallState mechanism).

Implements Subsystem.

Definition at line 1237 of file PosixSubsystem.cc.

References invoke().

bool PosixSubsystem::invoke ( File *  originalFile, const String &  originalName, Vector< String > &  argv, Vector< String > &  env  )

virtual

Invokes the given file (thread mechanism).

Implements Subsystem.

Definition at line 1378 of file PosixSubsystem.cc.

References invoke().

bool PosixSubsystem::invoke ( File *  originalFile, const String &  originalName, Vector< String > &  argv, Vector< String > &  env, SyscallState &  state  )

virtual

Invokes the given file (SyscallState mechanism).

Implements Subsystem.

Definition at line 1385 of file PosixSubsystem.cc.

References invoke().

bool PosixSubsystem::invoke ( File *  originalFile, const String &  originalName, Vector< String > &  argv, Vector< String > &  env, SyscallState *  state  )

private

Invokes the given command - actual implementation.

Todo:

actually we are supposed to kill them all here

Todo:

do we need to relocate at all?

Todo:

cleanup

Todo:

cleanup

Todo:

should only do this for setuid/setgid programs

Todo:

platform assumption here.

Todo:

16 random bytes, not 16 zero bytes

Definition at line 1392 of file PosixSubsystem.cc.

References VFS::checkAccess(), DynamicLinker::checkInterpreter(), Vector< T >::count(), Process::description(), Thread::detach(), VirtualAddressSpace::Execute, Elf::extractEntryPoint(), RangeList< T, Reversed >::free(), freeMultipleFds(), Process::getAddressSpace(), VirtualAddressSpace::getDynamicEnd(), Process::getDynamicSpaceAllocator(), VirtualAddressSpace::getDynamicStart(), File::getName(), Process::getNumThreads(), PhysicalMemoryManager::getPageSize(), Process::getSpaceAllocator(), Thread::getStateLevel(), Process::getThread(), Process::getType(), Process::getUserId(), VirtualAddressSpace::getUserReservedStart(), VirtualAddressSpace::getUserStart(), Processor::information(), MemoryMapManager::instance(), Processor::jumpUser(), loadElf(), MemoryMapManager::mapAnon(), MemoryMapManager::mapFile(), parseShebang(), Thread::popState(), File::read(), Process::recordTime(), Thread::resetTlsBase(), VirtualAddressSpace::revertToKernelAddressSpace(), Processor::setInterrupts(), MemoryMapManager::setPermissions(), Thread::state(), MemoryMapManager::unmap(), MemoryMapManager::unmapAll(), and Elf::validate().

bool PosixSubsystem::kill ( KillReason  killReason, Thread *  pThread  )

virtual

A thread needs to be killed!

Todo:

we probably want to avoid allocating a new stack..

Implements Subsystem.

Definition at line 510 of file PosixSubsystem.cc.

References ERROR, Process::getId(), Thread::getParent(), getSignalHandler(), Process::getType(), Processor::information(), Scheduler::instance(), PosixSubsystem::SignalHandler::pEvent, Thread::sendEvent(), Processor::setInterrupts(), and Scheduler::yield().

bool PosixSubsystem::loadElf ( File *  pFile, uintptr_t  mappedAddress, uintptr_t &  newAddress, uintptr_t &  finalAddress, bool &  relocated  )

private

Load an ELF's PT_LOAD sections into the address space.

Definition at line 990 of file PosixSubsystem.cc.

References ERROR, File::getName(), PhysicalMemoryManager::getPageSize(), Hex, Processor::information(), MemoryMapManager::instance(), MemoryMapManager::mapAnon(), and MemoryMapManager::mapFile().

Referenced by invoke().

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bool PosixSubsystem::parseShebang ( File *  pFile, File *&  outFile, Vector< String > &  argv  )

private

Parse a file for a possible shebang line.

Todo:

this loop could terminate MUCH faster

Definition at line 1244 of file PosixSubsystem.cc.

References Vector< T >::begin(), Vector< T >::count(), Symlink::followLink(), Symlink::fromFile(), File::getFullPath(), invoke(), File::isDirectory(), File::isSymlink(), Vector< T >::popBack(), Vector< T >::pushFront(), and File::read().

Referenced by invoke().

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void PosixSubsystem::release ( )

virtual

Release mutual exclusion acquired via acquire().

Reimplemented from Subsystem.

Definition at line 304 of file PosixSubsystem.cc.

References Spinlock::acquire(), m_bAcquired, m_FdLock, m_Lock, m_pAcquiredThread, m_SignalHandlersLock, Spinlock::release(), and UnlikelyLock::release().

Referenced by ~PosixSubsystem().

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void PosixSubsystem::removeSyncObject ( size_t  n )

inline

Removes a semaphore given a descriptor

Definition at line 353 of file PosixSubsystem.h.

void PosixSubsystem::removeThread ( size_t  n )

inline

Removes a thread given a descriptor

Todo:

It might be safe to delete the pointer... We'll see.

Definition at line 455 of file PosixSubsystem.h.

void PosixSubsystem::removeThreadWaiter ( void *  n )

inline

Removes a thread waiter object given a descriptor

Definition at line 479 of file PosixSubsystem.h.

void PosixSubsystem::sendSignal ( Thread *  pThread, int  signal, bool  yield = true  )

virtual

Send a POSIX signal to the given thread.

Definition at line 648 of file PosixSubsystem.cc.

References Dec, ERROR, Process::getId(), Thread::getId(), Thread::getParent(), getSignalHandler(), Thread::hasEvent(), Processor::information(), Scheduler::instance(), NOTICE, PosixSubsystem::SignalHandler::pEvent, Thread::sendEvent(), WARNING, and Scheduler::yield().

Referenced by IoEvent::IoEvent(), VirtualTerminalManager::setTerminalMode(), IntervalTimer::signal(), and threadException().

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void PosixSubsystem::setAbi ( Abi  which )

inline

Switch the ABI of the subsystem to the specified choice.

Definition at line 516 of file PosixSubsystem.h.

Referenced by PosixSyscallManager::syscall().

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void PosixSubsystem::setAlternateSignalStack ( AlternateSignalStack &  s )

inline

Sets the alternate signal stack, if possible

Definition at line 209 of file PosixSubsystem.h.

void PosixSubsystem::setSignalHandler	(	size_t	sig,
		SignalHandler *	handler
	)

Sets a signal handler

Definition at line 714 of file PosixSubsystem.cc.

References UnlikelyLock::acquire(), m_SignalHandlers, m_SignalHandlersLock, UnlikelyLock::release(), and PosixSubsystem::SignalHandler::sig.

void PosixSubsystem::threadException ( Thread *  pThread, ExceptionType  eType  )

virtual

A thread has thrown an exception!

Reimplemented from Subsystem.

Definition at line 556 of file PosixSubsystem.cc.

References Dec, ERROR, Process::getId(), Thread::getId(), Thread::getParent(), and sendSignal().

void PosixSubsystem::threadRemoved ( Thread *  pThread )

privatevirtual

Notifies the subsystem that the given thread has been removed.

Reimplemented from Subsystem.

Definition at line 965 of file PosixSubsystem.cc.

References VFS::checkAccess(), FileDescriptor::file, m_Threads, and Semaphore::release().

Member Data Documentation

Abi PosixSubsystem::m_Abi

private

ABI for the subsystem This affects syscall parameters and the behaviors of some syscalls.

Definition at line 595 of file PosixSubsystem.h.

AlternateSignalStack PosixSubsystem::m_AltSigStack

private

Alternate signal stack - if defined, used instead of a system-defined stack

Definition at line 576 of file PosixSubsystem.h.

bool PosixSubsystem::m_bAcquired

private

Are we acquired?

Definition at line 600 of file PosixSubsystem.h.

Referenced by acquire(), and release().

ExtensibleBitmap PosixSubsystem::m_FdBitmap

private

File descriptors used by this process

Definition at line 563 of file PosixSubsystem.h.

Referenced by allocateFd(), copyDescriptors(), freeFd(), freeMultipleFds(), and getFd().

UnlikelyLock PosixSubsystem::m_FdLock

private

Lock to guard the next file descriptor while it is being changed.

Definition at line 559 of file PosixSubsystem.h.

Referenced by acquire(), addFileDescriptor(), allocateFd(), copyDescriptors(), freeFd(), freeMultipleFds(), getFd(), getFileDescriptor(), and release().

Tree<size_t, FileDescriptor *> PosixSubsystem::m_FdMap

private

The file descriptor map. Maps number to pointers, the type of which is decided by the subsystem.

Definition at line 551 of file PosixSubsystem.h.

Referenced by addFileDescriptor(), copyDescriptors(), freeFd(), freeMultipleFds(), and getFileDescriptor().

int PosixSubsystem::m_FreeCount

private

Number of times freed

Definition at line 571 of file PosixSubsystem.h.

Referenced by ~PosixSubsystem().

size_t PosixSubsystem::m_LastFd

private

Last known unallocated descriptor

Definition at line 567 of file PosixSubsystem.h.

Referenced by freeFd(), freeMultipleFds(), and getFd().

Spinlock PosixSubsystem::m_Lock

private

Safety spinlock for mutual exclusion in acquire().

Definition at line 610 of file PosixSubsystem.h.

Referenced by acquire(), and release().

size_t PosixSubsystem::m_NextFd

private

The next available file descriptor.

Definition at line 555 of file PosixSubsystem.h.

Referenced by allocateFd(), copyDescriptors(), and getFd().

Thread* PosixSubsystem::m_pAcquiredThread

private

Which thread acquired?

Definition at line 605 of file PosixSubsystem.h.

Referenced by acquire(), and release().

Filesystem* PosixSubsystem::m_pRootFs = nullptr

private

Cached lookup of the root filesystem.

Definition at line 621 of file PosixSubsystem.h.

Referenced by findFile().

Tree<size_t, SignalHandler *> PosixSubsystem::m_SignalHandlers

private

Signal handlers

Definition at line 542 of file PosixSubsystem.h.

Referenced by PosixSubsystem(), setSignalHandler(), and ~PosixSubsystem().

UnlikelyLock PosixSubsystem::m_SignalHandlersLock

private

A lock for access to the signal handlers tree

Definition at line 545 of file PosixSubsystem.h.

Referenced by acquire(), PosixSubsystem(), release(), and setSignalHandler().

Tree<size_t, PosixSyncObject *> PosixSubsystem::m_SyncObjects

private

Links some file descriptors to PosixSyncObjects.

Definition at line 580 of file PosixSubsystem.h.

Referenced by ~PosixSubsystem().

Tree<size_t, PosixThread *> PosixSubsystem::m_Threads

private

Links some thread handles to Threads.

Definition at line 584 of file PosixSubsystem.h.

Referenced by threadRemoved(), and ~PosixSubsystem().

Tree<void *, Semaphore *> PosixSubsystem::m_ThreadWaiters

private

Links waiter objects to Semaphores.

Definition at line 588 of file PosixSubsystem.h.

Referenced by PosixSubsystem(), and ~PosixSubsystem().

const size_t PosixSubsystem::SafeRegion = 0x0

static

Sanitise flags.

Definition at line 109 of file PosixSubsystem.h.

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

• PosixSubsystem.h
• PosixSubsystem.cc