/*
* Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
* Copyright (C) 2007 Eric Seidel <eric@webkit.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include "config.h"
#include "StackBounds.h"
#if OS(DARWIN)
#include <mach/task.h>
#include <mach/thread_act.h>
#include <pthread.h>
#elif OS(WINDOWS)
#include <windows.h>
#elif OS(HAIKU)
#include <OS.h>
#elif OS(SOLARIS)
#include <thread.h>
#elif OS(QNX)
#include <fcntl.h>
#include <sys/procfs.h>
#include <stdio.h>
#include <errno.h>
#elif OS(UNIX)
#include <pthread.h>
#if HAVE(PTHREAD_NP_H)
#include <pthread_np.h>
#endif
#endif
namespace WTF {
// Bug 26276 - Need a mechanism to determine stack extent
//
// These platforms should now be working correctly:
// DARWIN, QNX, UNIX, SYMBIAN
// These platforms are not:
// WINDOWS, SOLARIS, OPENBSD, HAIKU, WINCE
//
// FIXME: remove this! - this code unsafely guesses at stack sizes!
#if OS(WINDOWS) || OS(SOLARIS) || OS(OPENBSD) || OS(HAIKU)
// Based on the current limit used by the JSC parser, guess the stack size.
static const ptrdiff_t estimatedStackSize = 128 * sizeof(void*) * 1024;
// This method assumes the stack is growing downwards.
static void* estimateStackBound(void* origin)
{
return static_cast<char*>(origin) - estimatedStackSize;
}
#endif
#if OS(DARWIN)
void StackBounds::initialize()
{
pthread_t thread = pthread_self();
m_origin = pthread_get_stackaddr_np(thread);
m_bound = static_cast<char*>(m_origin) - pthread_get_stacksize_np(thread);
}
#elif OS(QNX)
void StackBounds::initialize()
{
void* stackBase = 0;
size_t stackSize = 0;
pthread_t thread = pthread_self();
struct _debug_thread_info threadInfo;
memset(&threadInfo, 0, sizeof(threadInfo));
threadInfo.tid = pthread_self();
int fd = open("/proc/self", O_RDONLY);
if (fd == -1) {
LOG_ERROR("Unable to open /proc/self (errno: %d)", errno);
CRASH();
}
devctl(fd, DCMD_PROC_TIDSTATUS, &threadInfo, sizeof(threadInfo), 0);
close(fd);
stackBase = reinterpret_cast<void*>(threadInfo.stkbase);
stackSize = threadInfo.stksize;
ASSERT(stackBase);
m_bound = stackBase;
m_origin = static_cast<char*>(stackBase) + stackSize;
}
#elif OS(SOLARIS)
void StackBounds::initialize()
{
stack_t s;
thr_stksegment(&s);
m_origin = s.ss_sp;
m_bound = estimateStackBound(m_origin);
}
#elif OS(OPENBSD)
void StackBounds::initialize()
{
pthread_t thread = pthread_self();
stack_t stack;
pthread_stackseg_np(thread, &stack);
m_origin = stack.ss_sp;
m_bound = estimateStackBound(m_origin);
}
#elif OS(SYMBIAN)
void StackBounds::initialize()
{
TThreadStackInfo info;
RThread thread;
thread.StackInfo(info);
m_origin = (void*)info.iBase;
m_bound = (void*)info.iLimit;
}
#elif OS(HAIKU)
void StackBounds::initialize()
{
thread_info threadInfo;
get_thread_info(find_thread(NULL), &threadInfo);
m_origin = threadInfo.stack_end;
m_bound = estimateStackBound(m_origin);
}
#elif OS(UNIX)
void StackBounds::initialize()
{
void* stackBase = 0;
size_t stackSize = 0;
pthread_t thread = pthread_self();
pthread_attr_t sattr;
pthread_attr_init(&sattr);
#if HAVE(PTHREAD_NP_H) || OS(NETBSD)
// e.g. on FreeBSD 5.4, neundorf@kde.org
pthread_attr_get_np(thread, &sattr);
#else
// FIXME: this function is non-portable; other POSIX systems may have different np alternatives
pthread_getattr_np(thread, &sattr);
#endif
int rc = pthread_attr_getstack(&sattr, &stackBase, &stackSize);
(void)rc; // FIXME: Deal with error code somehow? Seems fatal.
ASSERT(stackBase);
pthread_attr_destroy(&sattr);
m_bound = stackBase;
m_origin = static_cast<char*>(stackBase) + stackSize;
}
#elif OS(WINCE)
static bool detectGrowingDownward(void* previousFrame)
{
// Find the address of this stack frame by taking the address of a local variable.
int thisFrame;
return previousFrame > &thisFrame;
}
static inline bool isPageWritable(void* page)
{
MEMORY_BASIC_INFORMATION memoryInformation;
DWORD result = VirtualQuery(page, &memoryInformation, sizeof(memoryInformation));
// return false on error, including ptr outside memory
if (result != sizeof(memoryInformation))
return false;
DWORD protect = memoryInformation.Protect & ~(PAGE_GUARD | PAGE_NOCACHE);
return protect == PAGE_READWRITE
|| protect == PAGE_WRITECOPY
|| protect == PAGE_EXECUTE_READWRITE
|| protect == PAGE_EXECUTE_WRITECOPY;
}
static inline void* getLowerStackBound(char* currentPage, DWORD pageSize)
{
while (currentPage > 0) {
// check for underflow
if (currentPage >= reinterpret_cast<char*>(pageSize))
currentPage -= pageSize;
else
currentPage = 0;
if (!isPageWritable(currentPage))
return currentPage + pageSize;
}
return 0;
}
static inline void* getUpperStackBound(char* currentPage, DWORD pageSize)
{
do {
// guaranteed to complete because isPageWritable returns false at end of memory
currentPage += pageSize;
} while (isPageWritable(currentPage));
return currentPage - pageSize;
}
void StackBounds::initialize()
{
// find the address of this stack frame by taking the address of a local variable
void* thisFrame = &thisFrame;
bool isGrowingDownward = detectGrowingDownward(thisFrame);
SYSTEM_INFO systemInfo;
GetSystemInfo(&systemInfo);
DWORD pageSize = systemInfo.dwPageSize;
// scan all of memory starting from this frame, and return the last writeable page found
char* currentPage = reinterpret_cast<char*>(reinterpret_cast<DWORD>(thisFrame) & ~(pageSize - 1));
void* lowerStackBound = getLowerStackBound(currentPage, pageSize);
void* upperStackBound = getUpperStackBound(currentPage, pageSize);
m_origin = isGrowingDownward ? upperStackBound : lowerStackBound;
m_bound = isGrowingDownward ? lowerStackBound : upperStackBound;
}
#elif OS(WINDOWS)
void StackBounds::initialize()
{
#if CPU(X86) && COMPILER(MSVC)
// offset 0x18 from the FS segment register gives a pointer to
// the thread information block for the current thread
NT_TIB* pTib;
__asm {
MOV EAX, FS:[18h]
MOV pTib, EAX
}
m_origin = static_cast<void*>(pTib->StackBase);
#elif CPU(X86) && COMPILER(GCC)
// offset 0x18 from the FS segment register gives a pointer to
// the thread information block for the current thread
NT_TIB* pTib;
asm ( "movl %%fs:0x18, %0\n"
: "=r" (pTib)
);
m_origin = static_cast<void*>(pTib->StackBase);
#elif CPU(X86_64)
PNT_TIB64 pTib = reinterpret_cast<PNT_TIB64>(NtCurrentTeb());
m_origin = reinterpret_cast<void*>(pTib->StackBase);
#else
#error Need a way to get the stack bounds on this platform (Windows)
#endif
// Looks like we should be able to get pTib->StackLimit
m_bound = estimateStackBound(m_origin);
}
#else
#error Need a way to get the stack bounds on this platform
#endif
} // namespace WTF