michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set shiftwidth=4 tabstop=8 autoindent cindent expandtab: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /* API for getting a stack trace of the C/C++ stack on the current thread */
michael@0: 
michael@0: #include "mozilla/Assertions.h"
michael@0: #include "mozilla/IntegerPrintfMacros.h"
michael@0: #include "mozilla/StackWalk.h"
michael@0: #include "nsStackWalkPrivate.h"
michael@0: 
michael@0: #include "nsStackWalk.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: // The presence of this address is the stack must stop the stack walk. If
michael@0: // there is no such address, the structure will be {nullptr, true}.
michael@0: struct CriticalAddress {
michael@0:   void* mAddr;
michael@0:   bool mInit;
michael@0: };
michael@0: static CriticalAddress gCriticalAddress;
michael@0: 
michael@0: // for _Unwind_Backtrace from libcxxrt or libunwind
michael@0: // cxxabi.h from libcxxrt implicitly includes unwind.h first
michael@0: #if defined(HAVE__UNWIND_BACKTRACE) && !defined(_GNU_SOURCE)
michael@0: #define _GNU_SOURCE
michael@0: #endif
michael@0: 
michael@0: #if defined(HAVE_DLOPEN) || defined(XP_MACOSX)
michael@0: #include <dlfcn.h>
michael@0: #endif
michael@0: 
michael@0: #define NSSTACKWALK_SUPPORTS_MACOSX \
michael@0:     (defined(XP_MACOSX) && \
michael@0:      (defined(__i386) || defined(__ppc__) || defined(HAVE__UNWIND_BACKTRACE)))
michael@0: 
michael@0: #define NSSTACKWALK_SUPPORTS_LINUX \
michael@0:     (defined(linux) && \
michael@0:      ((defined(__GNUC__) && (defined(__i386) || defined(PPC))) || \
michael@0:       defined(HAVE__UNWIND_BACKTRACE)))
michael@0: 
michael@0: #define NSSTACKWALK_SUPPORTS_SOLARIS \
michael@0:     (defined(__sun) && \
michael@0:      (defined(__sparc) || defined(sparc) || defined(__i386) || defined(i386)))
michael@0: 
michael@0: #if NSSTACKWALK_SUPPORTS_MACOSX
michael@0: #include <pthread.h>
michael@0: #include <CoreServices/CoreServices.h>
michael@0: 
michael@0: typedef void
michael@0: malloc_logger_t(uint32_t type, uintptr_t arg1, uintptr_t arg2, uintptr_t arg3,
michael@0:                 uintptr_t result, uint32_t num_hot_frames_to_skip);
michael@0: extern malloc_logger_t *malloc_logger;
michael@0: 
michael@0: static void
michael@0: stack_callback(void *pc, void *sp, void *closure)
michael@0: {
michael@0:   const char *name = reinterpret_cast<char *>(closure);
michael@0:   Dl_info info;
michael@0: 
michael@0:   // On Leopard dladdr returns the wrong value for "new_sem_from_pool". The
michael@0:   // stack shows up as having two pthread_cond_wait$UNIX2003 frames. The
michael@0:   // correct one is the first that we find on our way up, so the
michael@0:   // following check for gCriticalAddress.mAddr is critical.
michael@0:   if (gCriticalAddress.mAddr || dladdr(pc, &info) == 0  ||
michael@0:       info.dli_sname == nullptr || strcmp(info.dli_sname, name) != 0)
michael@0:     return;
michael@0:   gCriticalAddress.mAddr = pc;
michael@0: }
michael@0: 
michael@0: #ifdef DEBUG
michael@0: #define MAC_OS_X_VERSION_10_7_HEX 0x00001070
michael@0: 
michael@0: static int32_t OSXVersion()
michael@0: {
michael@0:   static int32_t gOSXVersion = 0x0;
michael@0:   if (gOSXVersion == 0x0) {
michael@0:     OSErr err = ::Gestalt(gestaltSystemVersion, (SInt32*)&gOSXVersion);
michael@0:     MOZ_ASSERT(err == noErr);
michael@0:   }
michael@0:   return gOSXVersion;
michael@0: }
michael@0: 
michael@0: static bool OnLionOrLater()
michael@0: {
michael@0:   return (OSXVersion() >= MAC_OS_X_VERSION_10_7_HEX);
michael@0: }
michael@0: #endif
michael@0: 
michael@0: static void
michael@0: my_malloc_logger(uint32_t type, uintptr_t arg1, uintptr_t arg2, uintptr_t arg3,
michael@0:                  uintptr_t result, uint32_t num_hot_frames_to_skip)
michael@0: {
michael@0:   static bool once = false;
michael@0:   if (once)
michael@0:     return;
michael@0:   once = true;
michael@0: 
michael@0:   // On Leopard dladdr returns the wrong value for "new_sem_from_pool". The
michael@0:   // stack shows up as having two pthread_cond_wait$UNIX2003 frames.
michael@0:   const char *name = "new_sem_from_pool";
michael@0:   NS_StackWalk(stack_callback, /* skipFrames */ 0, /* maxFrames */ 0,
michael@0:                const_cast<char*>(name), 0, nullptr);
michael@0: }
michael@0: 
michael@0: // This is called from NS_LogInit() and from the stack walking functions, but
michael@0: // only the first call has any effect.  We need to call this function from both
michael@0: // places because it must run before any mutexes are created, and also before
michael@0: // any objects whose refcounts we're logging are created.  Running this
michael@0: // function during NS_LogInit() ensures that we meet the first criterion, and
michael@0: // running this function during the stack walking functions ensures we meet the
michael@0: // second criterion.
michael@0: void
michael@0: StackWalkInitCriticalAddress()
michael@0: {
michael@0:   if(gCriticalAddress.mInit)
michael@0:     return;
michael@0:   gCriticalAddress.mInit = true;
michael@0:   // We must not do work when 'new_sem_from_pool' calls realloc, since
michael@0:   // it holds a non-reentrant spin-lock and we will quickly deadlock.
michael@0:   // new_sem_from_pool is not directly accessible using dlsym, so
michael@0:   // we force a situation where new_sem_from_pool is on the stack and
michael@0:   // use dladdr to check the addresses.
michael@0: 
michael@0:   // malloc_logger can be set by external tools like 'Instruments' or 'leaks'
michael@0:   malloc_logger_t *old_malloc_logger = malloc_logger;
michael@0:   malloc_logger = my_malloc_logger;
michael@0: 
michael@0:   pthread_cond_t cond;
michael@0:   int r = pthread_cond_init(&cond, 0);
michael@0:   MOZ_ASSERT(r == 0);
michael@0:   pthread_mutex_t mutex;
michael@0:   r = pthread_mutex_init(&mutex,0);
michael@0:   MOZ_ASSERT(r == 0);
michael@0:   r = pthread_mutex_lock(&mutex);
michael@0:   MOZ_ASSERT(r == 0);
michael@0:   struct timespec abstime = {0, 1};
michael@0:   r = pthread_cond_timedwait_relative_np(&cond, &mutex, &abstime);
michael@0: 
michael@0:   // restore the previous malloc logger
michael@0:   malloc_logger = old_malloc_logger;
michael@0: 
michael@0:   // On Lion, malloc is no longer called from pthread_cond_*wait*. This prevents
michael@0:   // us from finding the address, but that is fine, since with no call to malloc
michael@0:   // there is no critical address.
michael@0:   MOZ_ASSERT(OnLionOrLater() || gCriticalAddress.mAddr != nullptr);
michael@0:   MOZ_ASSERT(r == ETIMEDOUT);
michael@0:   r = pthread_mutex_unlock(&mutex);
michael@0:   MOZ_ASSERT(r == 0);
michael@0:   r = pthread_mutex_destroy(&mutex);
michael@0:   MOZ_ASSERT(r == 0);
michael@0:   r = pthread_cond_destroy(&cond);
michael@0:   MOZ_ASSERT(r == 0);
michael@0: }
michael@0: 
michael@0: static bool IsCriticalAddress(void* aPC)
michael@0: {
michael@0:   return gCriticalAddress.mAddr == aPC;
michael@0: }
michael@0: #else
michael@0: static bool IsCriticalAddress(void* aPC)
michael@0: {
michael@0:   return false;
michael@0: }
michael@0: // We still initialize gCriticalAddress.mInit so that this code behaves
michael@0: // the same on all platforms. Otherwise a failure to init would be visible
michael@0: // only on OS X.
michael@0: void
michael@0: StackWalkInitCriticalAddress()
michael@0: {
michael@0:   gCriticalAddress.mInit = true;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: #if defined(_WIN32) && (defined(_M_IX86) || defined(_M_AMD64) || defined(_M_IA64)) // WIN32 x86 stack walking code
michael@0: 
michael@0: #include "nscore.h"
michael@0: #include <windows.h>
michael@0: #include <process.h>
michael@0: #include <stdio.h>
michael@0: #include <malloc.h>
michael@0: #include "plstr.h"
michael@0: #include "mozilla/ArrayUtils.h"
michael@0: 
michael@0: #include "nspr.h"
michael@0: #include <imagehlp.h>
michael@0: // We need a way to know if we are building for WXP (or later), as if we are, we
michael@0: // need to use the newer 64-bit APIs. API_VERSION_NUMBER seems to fit the bill.
michael@0: // A value of 9 indicates we want to use the new APIs.
michael@0: #if API_VERSION_NUMBER < 9
michael@0: #error Too old imagehlp.h
michael@0: #endif
michael@0: 
michael@0: // Define these as static pointers so that we can load the DLL on the
michael@0: // fly (and not introduce a link-time dependency on it). Tip o' the
michael@0: // hat to Matt Pietrick for this idea. See:
michael@0: //
michael@0: //   http://msdn.microsoft.com/library/periodic/period97/F1/D3/S245C6.htm
michael@0: //
michael@0: extern "C" {
michael@0: 
michael@0: extern HANDLE hStackWalkMutex; 
michael@0: 
michael@0: bool EnsureSymInitialized();
michael@0: 
michael@0: bool EnsureWalkThreadReady();
michael@0: 
michael@0: struct WalkStackData {
michael@0:   uint32_t skipFrames;
michael@0:   HANDLE thread;
michael@0:   bool walkCallingThread;
michael@0:   HANDLE process;
michael@0:   HANDLE eventStart;
michael@0:   HANDLE eventEnd;
michael@0:   void **pcs;
michael@0:   uint32_t pc_size;
michael@0:   uint32_t pc_count;
michael@0:   uint32_t pc_max;
michael@0:   void **sps;
michael@0:   uint32_t sp_size;
michael@0:   uint32_t sp_count;
michael@0:   void *platformData;
michael@0: };
michael@0: 
michael@0: void PrintError(char *prefix, WalkStackData* data);
michael@0: unsigned int WINAPI WalkStackThread(void* data);
michael@0: void WalkStackMain64(struct WalkStackData* data);
michael@0: 
michael@0: 
michael@0: DWORD gStackWalkThread;
michael@0: CRITICAL_SECTION gDbgHelpCS;
michael@0: 
michael@0: }
michael@0: 
michael@0: // Routine to print an error message to standard error.
michael@0: void PrintError(const char *prefix)
michael@0: {
michael@0:     LPVOID lpMsgBuf;
michael@0:     DWORD lastErr = GetLastError();
michael@0:     FormatMessageA(
michael@0:       FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
michael@0:       nullptr,
michael@0:       lastErr,
michael@0:       MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
michael@0:       (LPSTR) &lpMsgBuf,
michael@0:       0,
michael@0:       nullptr
michael@0:     );
michael@0:     fprintf(stderr, "### ERROR: %s: %s",
michael@0:                     prefix, lpMsgBuf ? lpMsgBuf : "(null)\n");
michael@0:     fflush(stderr);
michael@0:     LocalFree(lpMsgBuf);
michael@0: }
michael@0: 
michael@0: bool
michael@0: EnsureWalkThreadReady()
michael@0: {
michael@0:     static bool walkThreadReady = false;
michael@0:     static HANDLE stackWalkThread = nullptr;
michael@0:     static HANDLE readyEvent = nullptr;
michael@0: 
michael@0:     if (walkThreadReady)
michael@0:         return walkThreadReady;
michael@0: 
michael@0:     if (stackWalkThread == nullptr) {
michael@0:         readyEvent = ::CreateEvent(nullptr, FALSE /* auto-reset*/,
michael@0:                                    FALSE /* initially non-signaled */,
michael@0:                                    nullptr);
michael@0:         if (readyEvent == nullptr) {
michael@0:             PrintError("CreateEvent");
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         unsigned int threadID;
michael@0:         stackWalkThread = (HANDLE)
michael@0:             _beginthreadex(nullptr, 0, WalkStackThread, (void*)readyEvent,
michael@0:                            0, &threadID);
michael@0:         if (stackWalkThread == nullptr) {
michael@0:             PrintError("CreateThread");
michael@0:             ::CloseHandle(readyEvent);
michael@0:             readyEvent = nullptr;
michael@0:             return false;
michael@0:         }
michael@0:         gStackWalkThread = threadID;
michael@0:         ::CloseHandle(stackWalkThread);
michael@0:     }
michael@0: 
michael@0:     MOZ_ASSERT((stackWalkThread != nullptr && readyEvent != nullptr) ||
michael@0:                (stackWalkThread == nullptr && readyEvent == nullptr));
michael@0: 
michael@0:     // The thread was created. Try to wait an arbitrary amount of time (1 second
michael@0:     // should be enough) for its event loop to start before posting events to it.
michael@0:     DWORD waitRet = ::WaitForSingleObject(readyEvent, 1000);
michael@0:     if (waitRet == WAIT_TIMEOUT) {
michael@0:         // We get a timeout if we're called during static initialization because
michael@0:         // the thread will only start executing after we return so it couldn't
michael@0:         // have signalled the event. If that is the case, give up for now and
michael@0:         // try again next time we're called.
michael@0:         return false;
michael@0:     }
michael@0:     ::CloseHandle(readyEvent);
michael@0:     stackWalkThread = nullptr;
michael@0:     readyEvent = nullptr;
michael@0: 
michael@0: 
michael@0:     ::InitializeCriticalSection(&gDbgHelpCS);
michael@0: 
michael@0:     return walkThreadReady = true;
michael@0: }
michael@0: 
michael@0: void
michael@0: WalkStackMain64(struct WalkStackData* data)
michael@0: {
michael@0:     // Get the context information for the thread. That way we will
michael@0:     // know where our sp, fp, pc, etc. are and can fill in the
michael@0:     // STACKFRAME64 with the initial values.
michael@0:     CONTEXT context;
michael@0:     HANDLE myProcess = data->process;
michael@0:     HANDLE myThread = data->thread;
michael@0:     DWORD64 addr;
michael@0:     DWORD64 spaddr;
michael@0:     STACKFRAME64 frame64;
michael@0:     // skip our own stack walking frames
michael@0:     int skip = (data->walkCallingThread ? 3 : 0) + data->skipFrames;
michael@0:     BOOL ok;
michael@0: 
michael@0:     // Get a context for the specified thread.
michael@0:     if (!data->platformData) {
michael@0:         memset(&context, 0, sizeof(CONTEXT));
michael@0:         context.ContextFlags = CONTEXT_FULL;
michael@0:         if (!GetThreadContext(myThread, &context)) {
michael@0:             if (data->walkCallingThread) {
michael@0:                 PrintError("GetThreadContext");
michael@0:             }
michael@0:             return;
michael@0:         }
michael@0:     } else {
michael@0:         context = *static_cast<CONTEXT*>(data->platformData);
michael@0:     }
michael@0: 
michael@0:     // Setup initial stack frame to walk from
michael@0:     memset(&frame64, 0, sizeof(frame64));
michael@0: #ifdef _M_IX86
michael@0:     frame64.AddrPC.Offset    = context.Eip;
michael@0:     frame64.AddrStack.Offset = context.Esp;
michael@0:     frame64.AddrFrame.Offset = context.Ebp;
michael@0: #elif defined _M_AMD64
michael@0:     frame64.AddrPC.Offset    = context.Rip;
michael@0:     frame64.AddrStack.Offset = context.Rsp;
michael@0:     frame64.AddrFrame.Offset = context.Rbp;
michael@0: #elif defined _M_IA64
michael@0:     frame64.AddrPC.Offset    = context.StIIP;
michael@0:     frame64.AddrStack.Offset = context.SP;
michael@0:     frame64.AddrFrame.Offset = context.RsBSP;
michael@0: #else
michael@0: #error "Should not have compiled this code"
michael@0: #endif
michael@0:     frame64.AddrPC.Mode      = AddrModeFlat;
michael@0:     frame64.AddrStack.Mode   = AddrModeFlat;
michael@0:     frame64.AddrFrame.Mode   = AddrModeFlat;
michael@0:     frame64.AddrReturn.Mode  = AddrModeFlat;
michael@0: 
michael@0:     // Now walk the stack
michael@0:     while (1) {
michael@0: 
michael@0:         // debug routines are not threadsafe, so grab the lock.
michael@0:         EnterCriticalSection(&gDbgHelpCS);
michael@0:         ok = StackWalk64(
michael@0: #ifdef _M_AMD64
michael@0:           IMAGE_FILE_MACHINE_AMD64,
michael@0: #elif defined _M_IA64
michael@0:           IMAGE_FILE_MACHINE_IA64,
michael@0: #elif defined _M_IX86
michael@0:           IMAGE_FILE_MACHINE_I386,
michael@0: #else
michael@0: #error "Should not have compiled this code"
michael@0: #endif
michael@0:           myProcess,
michael@0:           myThread,
michael@0:           &frame64,
michael@0:           &context,
michael@0:           nullptr,
michael@0:           SymFunctionTableAccess64, // function table access routine
michael@0:           SymGetModuleBase64,       // module base routine
michael@0:           0
michael@0:         );
michael@0:         LeaveCriticalSection(&gDbgHelpCS);
michael@0: 
michael@0:         if (ok) {
michael@0:             addr = frame64.AddrPC.Offset;
michael@0:             spaddr = frame64.AddrStack.Offset;
michael@0:          } else {
michael@0:             addr = 0;
michael@0:             spaddr = 0;
michael@0:             if (data->walkCallingThread) {
michael@0:                 PrintError("WalkStack64");
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         if (!ok || (addr == 0)) {
michael@0:             break;
michael@0:         }
michael@0: 
michael@0:         if (skip-- > 0) {
michael@0:             continue;
michael@0:         }
michael@0: 
michael@0:         if (data->pc_count < data->pc_size)
michael@0:             data->pcs[data->pc_count] = (void*)addr;
michael@0:         ++data->pc_count;
michael@0: 
michael@0:         if (data->sp_count < data->sp_size)
michael@0:             data->sps[data->sp_count] = (void*)spaddr;
michael@0:         ++data->sp_count;
michael@0: 
michael@0:         if (data->pc_max != 0 && data->pc_count == data->pc_max)
michael@0:             break;
michael@0: 
michael@0:         if (frame64.AddrReturn.Offset == 0)
michael@0:             break;
michael@0:     }
michael@0:     return;
michael@0: }
michael@0: 
michael@0: 
michael@0: unsigned int WINAPI
michael@0: WalkStackThread(void* aData)
michael@0: {
michael@0:     BOOL msgRet;
michael@0:     MSG msg;
michael@0: 
michael@0:     // Call PeekMessage to force creation of a message queue so that
michael@0:     // other threads can safely post events to us.
michael@0:     ::PeekMessage(&msg, nullptr, WM_USER, WM_USER, PM_NOREMOVE);
michael@0: 
michael@0:     // and tell the thread that created us that we're ready.
michael@0:     HANDLE readyEvent = (HANDLE)aData;
michael@0:     ::SetEvent(readyEvent);
michael@0: 
michael@0:     while ((msgRet = ::GetMessage(&msg, (HWND)-1, 0, 0)) != 0) {
michael@0:         if (msgRet == -1) {
michael@0:             PrintError("GetMessage");
michael@0:         } else {
michael@0:             DWORD ret;
michael@0: 
michael@0:             struct WalkStackData *data = (WalkStackData *)msg.lParam;
michael@0:             if (!data)
michael@0:               continue;
michael@0: 
michael@0:             // Don't suspend the calling thread until it's waiting for
michael@0:             // us; otherwise the number of frames on the stack could vary.
michael@0:             ret = ::WaitForSingleObject(data->eventStart, INFINITE);
michael@0:             if (ret != WAIT_OBJECT_0)
michael@0:                 PrintError("WaitForSingleObject");
michael@0: 
michael@0:             // Suspend the calling thread, dump his stack, and then resume him.
michael@0:             // He's currently waiting for us to finish so now should be a good time.
michael@0:             ret = ::SuspendThread( data->thread );
michael@0:             if (ret == -1) {
michael@0:                 PrintError("ThreadSuspend");
michael@0:             }
michael@0:             else {
michael@0:                 WalkStackMain64(data);
michael@0: 
michael@0:                 ret = ::ResumeThread(data->thread);
michael@0:                 if (ret == -1) {
michael@0:                     PrintError("ThreadResume");
michael@0:                 }
michael@0:             }
michael@0: 
michael@0:             ::SetEvent(data->eventEnd);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Walk the stack, translating PC's found into strings and recording the
michael@0:  * chain in aBuffer. For this to work properly, the DLLs must be rebased
michael@0:  * so that the address in the file agrees with the address in memory.
michael@0:  * Otherwise StackWalk will return FALSE when it hits a frame in a DLL
michael@0:  * whose in memory address doesn't match its in-file address.
michael@0:  */
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_StackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:              uint32_t aMaxFrames, void *aClosure, uintptr_t aThread,
michael@0:              void *aPlatformData)
michael@0: {
michael@0:     StackWalkInitCriticalAddress();
michael@0:     static HANDLE myProcess = nullptr;
michael@0:     HANDLE myThread;
michael@0:     DWORD walkerReturn;
michael@0:     struct WalkStackData data;
michael@0: 
michael@0:     if (!EnsureWalkThreadReady())
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     HANDLE targetThread = ::GetCurrentThread();
michael@0:     data.walkCallingThread = true;
michael@0:     if (aThread) {
michael@0:         HANDLE threadToWalk = reinterpret_cast<HANDLE> (aThread);
michael@0:         // walkCallingThread indicates whether we are walking the caller's stack
michael@0:         data.walkCallingThread = (threadToWalk == targetThread);
michael@0:         targetThread = threadToWalk;
michael@0:     }
michael@0: 
michael@0:     // We need to avoid calling fprintf and friends if we're walking the stack of
michael@0:     // another thread, in order to avoid deadlocks.
michael@0:     const bool shouldBeThreadSafe = !!aThread;
michael@0: 
michael@0:     // Have to duplicate handle to get a real handle.
michael@0:     if (!myProcess) {
michael@0:         if (!::DuplicateHandle(::GetCurrentProcess(),
michael@0:                                ::GetCurrentProcess(),
michael@0:                                ::GetCurrentProcess(),
michael@0:                                &myProcess,
michael@0:                                PROCESS_ALL_ACCESS, FALSE, 0)) {
michael@0:             if (!shouldBeThreadSafe) {
michael@0:                 PrintError("DuplicateHandle (process)");
michael@0:             }
michael@0:             return NS_ERROR_FAILURE;
michael@0:         }
michael@0:     }
michael@0:     if (!::DuplicateHandle(::GetCurrentProcess(),
michael@0:                            targetThread,
michael@0:                            ::GetCurrentProcess(),
michael@0:                            &myThread,
michael@0:                            THREAD_ALL_ACCESS, FALSE, 0)) {
michael@0:         if (!shouldBeThreadSafe) {
michael@0:             PrintError("DuplicateHandle (thread)");
michael@0:         }
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     data.skipFrames = aSkipFrames;
michael@0:     data.thread = myThread;
michael@0:     data.process = myProcess;
michael@0:     void *local_pcs[1024];
michael@0:     data.pcs = local_pcs;
michael@0:     data.pc_count = 0;
michael@0:     data.pc_size = ArrayLength(local_pcs);
michael@0:     data.pc_max = aMaxFrames;
michael@0:     void *local_sps[1024];
michael@0:     data.sps = local_sps;
michael@0:     data.sp_count = 0;
michael@0:     data.sp_size = ArrayLength(local_sps);
michael@0:     data.platformData = aPlatformData;
michael@0: 
michael@0:     if (aThread) {
michael@0:         // If we're walking the stack of another thread, we don't need to
michael@0:         // use a separate walker thread.
michael@0:         WalkStackMain64(&data);
michael@0: 
michael@0:         if (data.pc_count > data.pc_size) {
michael@0:             data.pcs = (void**) _alloca(data.pc_count * sizeof(void*));
michael@0:             data.pc_size = data.pc_count;
michael@0:             data.pc_count = 0;
michael@0:             data.sps = (void**) _alloca(data.sp_count * sizeof(void*));
michael@0:             data.sp_size = data.sp_count;
michael@0:             data.sp_count = 0;
michael@0:             WalkStackMain64(&data);
michael@0:         }
michael@0:     } else {
michael@0:         data.eventStart = ::CreateEvent(nullptr, FALSE /* auto-reset*/,
michael@0:                               FALSE /* initially non-signaled */, nullptr);
michael@0:         data.eventEnd = ::CreateEvent(nullptr, FALSE /* auto-reset*/,
michael@0:                             FALSE /* initially non-signaled */, nullptr);
michael@0: 
michael@0:         ::PostThreadMessage(gStackWalkThread, WM_USER, 0, (LPARAM)&data);
michael@0: 
michael@0:         walkerReturn = ::SignalObjectAndWait(data.eventStart,
michael@0:                            data.eventEnd, INFINITE, FALSE);
michael@0:         if (walkerReturn != WAIT_OBJECT_0 && !shouldBeThreadSafe)
michael@0:             PrintError("SignalObjectAndWait (1)");
michael@0:         if (data.pc_count > data.pc_size) {
michael@0:             data.pcs = (void**) _alloca(data.pc_count * sizeof(void*));
michael@0:             data.pc_size = data.pc_count;
michael@0:             data.pc_count = 0;
michael@0:             data.sps = (void**) _alloca(data.sp_count * sizeof(void*));
michael@0:             data.sp_size = data.sp_count;
michael@0:             data.sp_count = 0;
michael@0:             ::PostThreadMessage(gStackWalkThread, WM_USER, 0, (LPARAM)&data);
michael@0:             walkerReturn = ::SignalObjectAndWait(data.eventStart,
michael@0:                                data.eventEnd, INFINITE, FALSE);
michael@0:             if (walkerReturn != WAIT_OBJECT_0 && !shouldBeThreadSafe)
michael@0:                 PrintError("SignalObjectAndWait (2)");
michael@0:         }
michael@0: 
michael@0:         ::CloseHandle(data.eventStart);
michael@0:         ::CloseHandle(data.eventEnd);
michael@0:     }
michael@0: 
michael@0:     ::CloseHandle(myThread);
michael@0: 
michael@0:     for (uint32_t i = 0; i < data.pc_count; ++i)
michael@0:         (*aCallback)(data.pcs[i], data.sps[i], aClosure);
michael@0: 
michael@0:     return data.pc_count == 0 ? NS_ERROR_FAILURE : NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: static BOOL CALLBACK callbackEspecial64(
michael@0:   PCSTR aModuleName,
michael@0:   DWORD64 aModuleBase,
michael@0:   ULONG aModuleSize,
michael@0:   PVOID aUserContext)
michael@0: {
michael@0:     BOOL retval = TRUE;
michael@0:     DWORD64 addr = *(DWORD64*)aUserContext;
michael@0: 
michael@0:     /*
michael@0:      * You'll want to control this if we are running on an
michael@0:      *  architecture where the addresses go the other direction.
michael@0:      * Not sure this is even a realistic consideration.
michael@0:      */
michael@0:     const BOOL addressIncreases = TRUE;
michael@0: 
michael@0:     /*
michael@0:      * If it falls in side the known range, load the symbols.
michael@0:      */
michael@0:     if (addressIncreases
michael@0:        ? (addr >= aModuleBase && addr <= (aModuleBase + aModuleSize))
michael@0:        : (addr <= aModuleBase && addr >= (aModuleBase - aModuleSize))
michael@0:         ) {
michael@0:         retval = !!SymLoadModule64(GetCurrentProcess(), nullptr,
michael@0:                                    (PSTR)aModuleName, nullptr,
michael@0:                                    aModuleBase, aModuleSize);
michael@0:         if (!retval)
michael@0:             PrintError("SymLoadModule64");
michael@0:     }
michael@0: 
michael@0:     return retval;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * SymGetModuleInfoEspecial
michael@0:  *
michael@0:  * Attempt to determine the module information.
michael@0:  * Bug 112196 says this DLL may not have been loaded at the time
michael@0:  *  SymInitialize was called, and thus the module information
michael@0:  *  and symbol information is not available.
michael@0:  * This code rectifies that problem.
michael@0:  */
michael@0: 
michael@0: // New members were added to IMAGEHLP_MODULE64 (that show up in the
michael@0: // Platform SDK that ships with VC8, but not the Platform SDK that ships
michael@0: // with VC7.1, i.e., between DbgHelp 6.0 and 6.1), but we don't need to
michael@0: // use them, and it's useful to be able to function correctly with the
michael@0: // older library.  (Stock Windows XP SP2 seems to ship with dbghelp.dll
michael@0: // version 5.1.)  Since Platform SDK version need not correspond to
michael@0: // compiler version, and the version number in debughlp.h was NOT bumped
michael@0: // when these changes were made, ifdef based on a constant that was
michael@0: // added between these versions.
michael@0: #ifdef SSRVOPT_SETCONTEXT
michael@0: #define NS_IMAGEHLP_MODULE64_SIZE (((offsetof(IMAGEHLP_MODULE64, LoadedPdbName) + sizeof(DWORD64) - 1) / sizeof(DWORD64)) * sizeof(DWORD64))
michael@0: #else
michael@0: #define NS_IMAGEHLP_MODULE64_SIZE sizeof(IMAGEHLP_MODULE64)
michael@0: #endif
michael@0: 
michael@0: BOOL SymGetModuleInfoEspecial64(HANDLE aProcess, DWORD64 aAddr, PIMAGEHLP_MODULE64 aModuleInfo, PIMAGEHLP_LINE64 aLineInfo)
michael@0: {
michael@0:     BOOL retval = FALSE;
michael@0: 
michael@0:     /*
michael@0:      * Init the vars if we have em.
michael@0:      */
michael@0:     aModuleInfo->SizeOfStruct = NS_IMAGEHLP_MODULE64_SIZE;
michael@0:     if (nullptr != aLineInfo) {
michael@0:         aLineInfo->SizeOfStruct = sizeof(IMAGEHLP_LINE64);
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * Give it a go.
michael@0:      * It may already be loaded.
michael@0:      */
michael@0:     retval = SymGetModuleInfo64(aProcess, aAddr, aModuleInfo);
michael@0: 
michael@0:     if (FALSE == retval) {
michael@0:         BOOL enumRes = FALSE;
michael@0: 
michael@0:         /*
michael@0:          * Not loaded, here's the magic.
michael@0:          * Go through all the modules.
michael@0:          */
michael@0:         // Need to cast to PENUMLOADED_MODULES_CALLBACK64 because the
michael@0:         // constness of the first parameter of
michael@0:         // PENUMLOADED_MODULES_CALLBACK64 varies over SDK versions (from
michael@0:         // non-const to const over time).  See bug 391848 and bug
michael@0:         // 415426.
michael@0:         enumRes = EnumerateLoadedModules64(aProcess, (PENUMLOADED_MODULES_CALLBACK64)callbackEspecial64, (PVOID)&aAddr);
michael@0:         if (FALSE != enumRes)
michael@0:         {
michael@0:             /*
michael@0:              * One final go.
michael@0:              * If it fails, then well, we have other problems.
michael@0:              */
michael@0:             retval = SymGetModuleInfo64(aProcess, aAddr, aModuleInfo);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * If we got module info, we may attempt line info as well.
michael@0:      * We will not report failure if this does not work.
michael@0:      */
michael@0:     if (FALSE != retval && nullptr != aLineInfo) {
michael@0:         DWORD displacement = 0;
michael@0:         BOOL lineRes = FALSE;
michael@0:         lineRes = SymGetLineFromAddr64(aProcess, aAddr, &displacement, aLineInfo);
michael@0:         if (!lineRes) {
michael@0:             // Clear out aLineInfo to indicate that it's not valid
michael@0:             memset(aLineInfo, 0, sizeof(*aLineInfo));
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return retval;
michael@0: }
michael@0: 
michael@0: bool
michael@0: EnsureSymInitialized()
michael@0: {
michael@0:     static bool gInitialized = false;
michael@0:     bool retStat;
michael@0: 
michael@0:     if (gInitialized)
michael@0:         return gInitialized;
michael@0: 
michael@0:     if (!EnsureWalkThreadReady())
michael@0:         return false;
michael@0: 
michael@0:     SymSetOptions(SYMOPT_LOAD_LINES | SYMOPT_UNDNAME);
michael@0:     retStat = SymInitialize(GetCurrentProcess(), nullptr, TRUE);
michael@0:     if (!retStat)
michael@0:         PrintError("SymInitialize");
michael@0: 
michael@0:     gInitialized = retStat;
michael@0:     /* XXX At some point we need to arrange to call SymCleanup */
michael@0: 
michael@0:     return retStat;
michael@0: }
michael@0: 
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_DescribeCodeAddress(void *aPC, nsCodeAddressDetails *aDetails)
michael@0: {
michael@0:     aDetails->library[0] = '\0';
michael@0:     aDetails->loffset = 0;
michael@0:     aDetails->filename[0] = '\0';
michael@0:     aDetails->lineno = 0;
michael@0:     aDetails->function[0] = '\0';
michael@0:     aDetails->foffset = 0;
michael@0: 
michael@0:     if (!EnsureSymInitialized())
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     HANDLE myProcess = ::GetCurrentProcess();
michael@0:     BOOL ok;
michael@0: 
michael@0:     // debug routines are not threadsafe, so grab the lock.
michael@0:     EnterCriticalSection(&gDbgHelpCS);
michael@0: 
michael@0:     //
michael@0:     // Attempt to load module info before we attempt to resolve the symbol.
michael@0:     // This just makes sure we get good info if available.
michael@0:     //
michael@0: 
michael@0:     DWORD64 addr = (DWORD64)aPC;
michael@0:     IMAGEHLP_MODULE64 modInfo;
michael@0:     IMAGEHLP_LINE64 lineInfo;
michael@0:     BOOL modInfoRes;
michael@0:     modInfoRes = SymGetModuleInfoEspecial64(myProcess, addr, &modInfo, &lineInfo);
michael@0: 
michael@0:     if (modInfoRes) {
michael@0:         PL_strncpyz(aDetails->library, modInfo.ModuleName,
michael@0:                     sizeof(aDetails->library));
michael@0:         aDetails->loffset = (char*) aPC - (char*) modInfo.BaseOfImage;
michael@0:         
michael@0:         if (lineInfo.FileName) {
michael@0:             PL_strncpyz(aDetails->filename, lineInfo.FileName,
michael@0:                         sizeof(aDetails->filename));
michael@0:             aDetails->lineno = lineInfo.LineNumber;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     ULONG64 buffer[(sizeof(SYMBOL_INFO) +
michael@0:       MAX_SYM_NAME*sizeof(TCHAR) + sizeof(ULONG64) - 1) / sizeof(ULONG64)];
michael@0:     PSYMBOL_INFO pSymbol = (PSYMBOL_INFO)buffer;
michael@0:     pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
michael@0:     pSymbol->MaxNameLen = MAX_SYM_NAME;
michael@0: 
michael@0:     DWORD64 displacement;
michael@0:     ok = SymFromAddr(myProcess, addr, &displacement, pSymbol);
michael@0: 
michael@0:     if (ok) {
michael@0:         PL_strncpyz(aDetails->function, pSymbol->Name,
michael@0:                     sizeof(aDetails->function));
michael@0:         aDetails->foffset = static_cast<ptrdiff_t>(displacement);
michael@0:     }
michael@0: 
michael@0:     LeaveCriticalSection(&gDbgHelpCS); // release our lock
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_FormatCodeAddressDetails(void *aPC, const nsCodeAddressDetails *aDetails,
michael@0:                             char *aBuffer, uint32_t aBufferSize)
michael@0: {
michael@0:     if (aDetails->function[0]) {
michael@0:         _snprintf(aBuffer, aBufferSize, "%s+0x%08lX [%s +0x%016lX]",
michael@0:                   aDetails->function, aDetails->foffset,
michael@0:                   aDetails->library, aDetails->loffset);
michael@0:     } else if (aDetails->library[0]) {
michael@0:         _snprintf(aBuffer, aBufferSize, "UNKNOWN [%s +0x%016lX]",
michael@0:                   aDetails->library, aDetails->loffset);
michael@0:     } else {
michael@0:         _snprintf(aBuffer, aBufferSize, "UNKNOWN 0x%016lX", aPC);
michael@0:     }
michael@0: 
michael@0:     aBuffer[aBufferSize - 1] = '\0';
michael@0: 
michael@0:     uint32_t len = strlen(aBuffer);
michael@0:     if (aDetails->filename[0]) {
michael@0:         _snprintf(aBuffer + len, aBufferSize - len, " (%s, line %d)\n",
michael@0:                   aDetails->filename, aDetails->lineno);
michael@0:     } else {
michael@0:         aBuffer[len] = '\n';
michael@0:         if (++len != aBufferSize)
michael@0:             aBuffer[len] = '\0';
michael@0:     }
michael@0:     aBuffer[aBufferSize - 2] = '\n';
michael@0:     aBuffer[aBufferSize - 1] = '\0';
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: // WIN32 x86 stack walking code
michael@0: // i386 or PPC Linux stackwalking code or Solaris
michael@0: #elif HAVE_DLADDR && (HAVE__UNWIND_BACKTRACE || NSSTACKWALK_SUPPORTS_LINUX || NSSTACKWALK_SUPPORTS_SOLARIS || NSSTACKWALK_SUPPORTS_MACOSX)
michael@0: 
michael@0: #include <stdlib.h>
michael@0: #include <string.h>
michael@0: #include "nscore.h"
michael@0: #include <stdio.h>
michael@0: #include "plstr.h"
michael@0: 
michael@0: // On glibc 2.1, the Dl_info api defined in <dlfcn.h> is only exposed
michael@0: // if __USE_GNU is defined.  I suppose its some kind of standards
michael@0: // adherence thing.
michael@0: //
michael@0: #if (__GLIBC_MINOR__ >= 1) && !defined(__USE_GNU)
michael@0: #define __USE_GNU
michael@0: #endif
michael@0: 
michael@0: // This thing is exported by libstdc++
michael@0: // Yes, this is a gcc only hack
michael@0: #if defined(MOZ_DEMANGLE_SYMBOLS)
michael@0: #include <cxxabi.h>
michael@0: #endif // MOZ_DEMANGLE_SYMBOLS
michael@0: 
michael@0: void DemangleSymbol(const char * aSymbol, 
michael@0:                     char * aBuffer,
michael@0:                     int aBufLen)
michael@0: {
michael@0:     aBuffer[0] = '\0';
michael@0: 
michael@0: #if defined(MOZ_DEMANGLE_SYMBOLS)
michael@0:     /* See demangle.h in the gcc source for the voodoo */
michael@0:     char * demangled = abi::__cxa_demangle(aSymbol,0,0,0);
michael@0: 
michael@0:     if (demangled)
michael@0:     {
michael@0:         PL_strncpyz(aBuffer,demangled,aBufLen);
michael@0:         free(demangled);
michael@0:     }
michael@0: #endif // MOZ_DEMANGLE_SYMBOLS
michael@0: }
michael@0: 
michael@0: 
michael@0: #if NSSTACKWALK_SUPPORTS_SOLARIS
michael@0: 
michael@0: /*
michael@0:  * Stack walking code for Solaris courtesy of Bart Smaalder's "memtrak".
michael@0:  */
michael@0: 
michael@0: #include <synch.h>
michael@0: #include <ucontext.h>
michael@0: #include <sys/frame.h>
michael@0: #include <sys/regset.h>
michael@0: #include <sys/stack.h>
michael@0: 
michael@0: static int    load_address ( void * pc, void * arg );
michael@0: static struct bucket * newbucket ( void * pc );
michael@0: static struct frame * cs_getmyframeptr ( void );
michael@0: static void   cs_walk_stack ( void * (*read_func)(char * address),
michael@0:                               struct frame * fp,
michael@0:                               int (*operate_func)(void *, void *, void *),
michael@0:                               void * usrarg );
michael@0: static void   cs_operate ( void (*operate_func)(void *, void *, void *),
michael@0:                            void * usrarg );
michael@0: 
michael@0: #ifndef STACK_BIAS
michael@0: #define STACK_BIAS 0
michael@0: #endif /*STACK_BIAS*/
michael@0: 
michael@0: #define LOGSIZE 4096
michael@0: 
michael@0: /* type of demangling function */
michael@0: typedef int demf_t(const char *, char *, size_t);
michael@0: 
michael@0: static demf_t *demf;
michael@0: 
michael@0: static int initialized = 0;
michael@0: 
michael@0: #if defined(sparc) || defined(__sparc)
michael@0: #define FRAME_PTR_REGISTER REG_SP
michael@0: #endif
michael@0: 
michael@0: #if defined(i386) || defined(__i386)
michael@0: #define FRAME_PTR_REGISTER EBP
michael@0: #endif
michael@0: 
michael@0: struct bucket {
michael@0:     void * pc;
michael@0:     int index;
michael@0:     struct bucket * next;
michael@0: };
michael@0: 
michael@0: struct my_user_args {
michael@0:     NS_WalkStackCallback callback;
michael@0:     uint32_t skipFrames;
michael@0:     uint32_t maxFrames;
michael@0:     uint32_t numFrames;
michael@0:     void *closure;
michael@0: };
michael@0: 
michael@0: 
michael@0: static void myinit();
michael@0: 
michael@0: #pragma init (myinit)
michael@0: 
michael@0: static void
michael@0: myinit()
michael@0: {
michael@0: 
michael@0:     if (! initialized) {
michael@0: #ifndef __GNUC__
michael@0:         void *handle;
michael@0:         const char *libdem = "libdemangle.so.1";
michael@0: 
michael@0:         /* load libdemangle if we can and need to (only try this once) */
michael@0:         if ((handle = dlopen(libdem, RTLD_LAZY)) != nullptr) {
michael@0:             demf = (demf_t *)dlsym(handle,
michael@0:                            "cplus_demangle"); /*lint !e611 */
michael@0:                 /*
michael@0:                  * lint override above is to prevent lint from
michael@0:                  * complaining about "suspicious cast".
michael@0:                  */
michael@0:         }
michael@0: #endif /*__GNUC__*/
michael@0:     }    
michael@0:     initialized = 1;
michael@0: }
michael@0: 
michael@0: 
michael@0: static int
michael@0: load_address(void * pc, void * arg)
michael@0: {
michael@0:     static struct bucket table[2048];
michael@0:     static mutex_t lock;
michael@0:     struct bucket * ptr;
michael@0:     struct my_user_args * args = (struct my_user_args *) arg;
michael@0: 
michael@0:     unsigned int val = NS_PTR_TO_INT32(pc);
michael@0: 
michael@0:     ptr = table + ((val >> 2)&2047);
michael@0: 
michael@0:     mutex_lock(&lock);
michael@0:     while (ptr->next) {
michael@0:         if (ptr->next->pc == pc)
michael@0:             break;
michael@0:         ptr = ptr->next;
michael@0:     }
michael@0: 
michael@0:     int stop = 0;
michael@0:     if (ptr->next) {
michael@0:         mutex_unlock(&lock);
michael@0:     } else {
michael@0:         (args->callback)(pc, args->closure);
michael@0:         args->numFrames++;
michael@0:         if (args->maxFrames != 0 && args->numFrames == args->maxFrames)
michael@0:           stop = 1;   // causes us to stop getting frames
michael@0: 
michael@0:         ptr->next = newbucket(pc);
michael@0:         mutex_unlock(&lock);
michael@0:     }
michael@0:     return stop;
michael@0: }
michael@0: 
michael@0: 
michael@0: static struct bucket *
michael@0: newbucket(void * pc)
michael@0: {
michael@0:     struct bucket * ptr = (struct bucket *) malloc(sizeof (*ptr));
michael@0:     static int index; /* protected by lock in caller */
michael@0:                      
michael@0:     ptr->index = index++;
michael@0:     ptr->next = nullptr;
michael@0:     ptr->pc = pc;    
michael@0:     return (ptr);    
michael@0: }
michael@0: 
michael@0: 
michael@0: static struct frame *
michael@0: csgetframeptr()
michael@0: {
michael@0:     ucontext_t u;
michael@0:     struct frame *fp;
michael@0: 
michael@0:     (void) getcontext(&u);
michael@0: 
michael@0:     fp = (struct frame *)
michael@0:         ((char *)u.uc_mcontext.gregs[FRAME_PTR_REGISTER] +
michael@0:         STACK_BIAS);
michael@0: 
michael@0:     /* make sure to return parents frame pointer.... */
michael@0: 
michael@0:     return ((struct frame *)((ulong_t)fp->fr_savfp + STACK_BIAS));
michael@0: }
michael@0: 
michael@0: 
michael@0: static void
michael@0: cswalkstack(struct frame *fp, int (*operate_func)(void *, void *, void *),
michael@0:     void *usrarg)
michael@0: {
michael@0: 
michael@0:     while (fp != 0 && fp->fr_savpc != 0) {
michael@0: 
michael@0:         if (operate_func((void *)fp->fr_savpc, nullptr, usrarg) != 0)
michael@0:             break;
michael@0:         /*
michael@0:          * watch out - libthread stacks look funny at the top
michael@0:          * so they may not have their STACK_BIAS set
michael@0:          */
michael@0: 
michael@0:         fp = (struct frame *)((ulong_t)fp->fr_savfp +
michael@0:             (fp->fr_savfp?(ulong_t)STACK_BIAS:0));
michael@0:     }
michael@0: }
michael@0: 
michael@0: 
michael@0: static void
michael@0: cs_operate(int (*operate_func)(void *, void *, void *), void * usrarg)
michael@0: {
michael@0:     cswalkstack(csgetframeptr(), operate_func, usrarg);
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_StackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:              uint32_t aMaxFrames, void *aClosure, uintptr_t aThread,
michael@0:              void *aPlatformData)
michael@0: {
michael@0:     MOZ_ASSERT(!aThread);
michael@0:     MOZ_ASSERT(!aPlatformData);
michael@0:     struct my_user_args args;
michael@0: 
michael@0:     StackWalkInitCriticalAddress();
michael@0: 
michael@0:     if (!initialized)
michael@0:         myinit();
michael@0: 
michael@0:     args.callback = aCallback;
michael@0:     args.skipFrames = aSkipFrames; /* XXX Not handled! */
michael@0:     args.maxFrames = aMaxFrames;
michael@0:     args.numFrames = 0;
michael@0:     args.closure = aClosure;
michael@0:     cs_operate(load_address, &args);
michael@0:     return args.numFrames == 0 ? NS_ERROR_FAILURE : NS_OK;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_DescribeCodeAddress(void *aPC, nsCodeAddressDetails *aDetails)
michael@0: {
michael@0:     aDetails->library[0] = '\0';
michael@0:     aDetails->loffset = 0;
michael@0:     aDetails->filename[0] = '\0';
michael@0:     aDetails->lineno = 0;
michael@0:     aDetails->function[0] = '\0';
michael@0:     aDetails->foffset = 0;
michael@0: 
michael@0:     char dembuff[4096];
michael@0:     Dl_info info;
michael@0: 
michael@0:     if (dladdr(aPC, & info)) {
michael@0:         if (info.dli_fname) {
michael@0:             PL_strncpyz(aDetails->library, info.dli_fname,
michael@0:                         sizeof(aDetails->library));
michael@0:             aDetails->loffset = (char*)aPC - (char*)info.dli_fbase;
michael@0:         }
michael@0:         if (info.dli_sname) {
michael@0:             aDetails->foffset = (char*)aPC - (char*)info.dli_saddr;
michael@0: #ifdef __GNUC__
michael@0:             DemangleSymbol(info.dli_sname, dembuff, sizeof(dembuff));
michael@0: #else
michael@0:             if (!demf || demf(info.dli_sname, dembuff, sizeof (dembuff)))
michael@0:                 dembuff[0] = 0;
michael@0: #endif /*__GNUC__*/
michael@0:             PL_strncpyz(aDetails->function,
michael@0:                         (dembuff[0] != '\0') ? dembuff : info.dli_sname,
michael@0:                         sizeof(aDetails->function));
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_FormatCodeAddressDetails(void *aPC, const nsCodeAddressDetails *aDetails,
michael@0:                             char *aBuffer, uint32_t aBufferSize)
michael@0: {
michael@0:     snprintf(aBuffer, aBufferSize, "%p %s:%s+0x%lx\n",
michael@0:              aPC,
michael@0:              aDetails->library[0] ? aDetails->library : "??",
michael@0:              aDetails->function[0] ? aDetails->function : "??",
michael@0:              aDetails->foffset);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: #else // not __sun-specific
michael@0: 
michael@0: #if __GLIBC__ > 2 || __GLIBC_MINOR > 1
michael@0: #define HAVE___LIBC_STACK_END 1
michael@0: #else
michael@0: #define HAVE___LIBC_STACK_END 0
michael@0: #endif
michael@0: 
michael@0: #if HAVE___LIBC_STACK_END
michael@0: extern void *__libc_stack_end; // from ld-linux.so
michael@0: #endif
michael@0: namespace mozilla {
michael@0: nsresult
michael@0: FramePointerStackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:                       uint32_t aMaxFrames, void *aClosure, void **bp,
michael@0:                       void *aStackEnd)
michael@0: {
michael@0:   // Stack walking code courtesy Kipp's "leaky".
michael@0: 
michael@0:   int32_t skip = aSkipFrames;
michael@0:   uint32_t numFrames = 0;
michael@0:   while (1) {
michael@0:     void **next = (void**)*bp;
michael@0:     // bp may not be a frame pointer on i386 if code was compiled with
michael@0:     // -fomit-frame-pointer, so do some sanity checks.
michael@0:     // (bp should be a frame pointer on ppc(64) but checking anyway may help
michael@0:     // a little if the stack has been corrupted.)
michael@0:     // We don't need to check against the begining of the stack because
michael@0:     // we can assume that bp > sp
michael@0:     if (next <= bp ||
michael@0:         next > aStackEnd ||
michael@0:         (long(next) & 3)) {
michael@0:       break;
michael@0:     }
michael@0: #if (defined(__ppc__) && defined(XP_MACOSX)) || defined(__powerpc64__)
michael@0:     // ppc mac or powerpc64 linux
michael@0:     void *pc = *(bp+2);
michael@0:     bp += 3;
michael@0: #else // i386 or powerpc32 linux
michael@0:     void *pc = *(bp+1);
michael@0:     bp += 2;
michael@0: #endif
michael@0:     if (IsCriticalAddress(pc)) {
michael@0:       printf("Aborting stack trace, PC is critical\n");
michael@0:       return NS_ERROR_UNEXPECTED;
michael@0:     }
michael@0:     if (--skip < 0) {
michael@0:       // Assume that the SP points to the BP of the function
michael@0:       // it called. We can't know the exact location of the SP
michael@0:       // but this should be sufficient for our use the SP
michael@0:       // to order elements on the stack.
michael@0:       (*aCallback)(pc, bp, aClosure);
michael@0:       numFrames++;
michael@0:       if (aMaxFrames != 0 && numFrames == aMaxFrames)
michael@0:         break;
michael@0:     }
michael@0:     bp = next;
michael@0:   }
michael@0:   return numFrames == 0 ? NS_ERROR_FAILURE : NS_OK;
michael@0: }
michael@0: 
michael@0: }
michael@0: 
michael@0: #define X86_OR_PPC (defined(__i386) || defined(PPC) || defined(__ppc__))
michael@0: #if X86_OR_PPC && (NSSTACKWALK_SUPPORTS_MACOSX || NSSTACKWALK_SUPPORTS_LINUX) // i386 or PPC Linux or Mac stackwalking code
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_StackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:              uint32_t aMaxFrames, void *aClosure, uintptr_t aThread,
michael@0:              void *aPlatformData)
michael@0: {
michael@0:   MOZ_ASSERT(!aThread);
michael@0:   MOZ_ASSERT(!aPlatformData);
michael@0:   StackWalkInitCriticalAddress();
michael@0: 
michael@0:   // Get the frame pointer
michael@0:   void **bp;
michael@0: #if defined(__i386) 
michael@0:   __asm__( "movl %%ebp, %0" : "=g"(bp));
michael@0: #else
michael@0:   // It would be nice if this worked uniformly, but at least on i386 and
michael@0:   // x86_64, it stopped working with gcc 4.1, because it points to the
michael@0:   // end of the saved registers instead of the start.
michael@0:   bp = (void**) __builtin_frame_address(0);
michael@0: #endif
michael@0: 
michael@0:   void *stackEnd;
michael@0: #if HAVE___LIBC_STACK_END
michael@0:   stackEnd = __libc_stack_end;
michael@0: #else
michael@0:   stackEnd = reinterpret_cast<void*>(-1);
michael@0: #endif
michael@0:   return FramePointerStackWalk(aCallback, aSkipFrames, aMaxFrames,
michael@0:                                aClosure, bp, stackEnd);
michael@0: 
michael@0: }
michael@0: 
michael@0: #elif defined(HAVE__UNWIND_BACKTRACE)
michael@0: 
michael@0: // libgcc_s.so symbols _Unwind_Backtrace@@GCC_3.3 and _Unwind_GetIP@@GCC_3.0
michael@0: #include <unwind.h>
michael@0: 
michael@0: struct unwind_info {
michael@0:     NS_WalkStackCallback callback;
michael@0:     int skip;
michael@0:     int maxFrames;
michael@0:     int numFrames;
michael@0:     bool isCriticalAbort;
michael@0:     void *closure;
michael@0: };
michael@0: 
michael@0: static _Unwind_Reason_Code
michael@0: unwind_callback (struct _Unwind_Context *context, void *closure)
michael@0: {
michael@0:     unwind_info *info = static_cast<unwind_info *>(closure);
michael@0:     void *pc = reinterpret_cast<void *>(_Unwind_GetIP(context));
michael@0:     // TODO Use something like '_Unwind_GetGR()' to get the stack pointer.
michael@0:     if (IsCriticalAddress(pc)) {
michael@0:         printf("Aborting stack trace, PC is critical\n");
michael@0:         info->isCriticalAbort = true;
michael@0:         // We just want to stop the walk, so any error code will do.  Using
michael@0:         // _URC_NORMAL_STOP would probably be the most accurate, but it is not
michael@0:         // defined on Android for ARM.
michael@0:         return _URC_FOREIGN_EXCEPTION_CAUGHT;
michael@0:     }
michael@0:     if (--info->skip < 0) {
michael@0:         (*info->callback)(pc, nullptr, info->closure);
michael@0:         info->numFrames++;
michael@0:         if (info->maxFrames != 0 && info->numFrames == info->maxFrames) {
michael@0:             // Again, any error code that stops the walk will do.
michael@0:             return _URC_FOREIGN_EXCEPTION_CAUGHT;
michael@0:         }
michael@0:     }
michael@0:     return _URC_NO_REASON;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_StackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:              uint32_t aMaxFrames, void *aClosure, uintptr_t aThread,
michael@0:              void *aPlatformData)
michael@0: {
michael@0:     MOZ_ASSERT(!aThread);
michael@0:     MOZ_ASSERT(!aPlatformData);
michael@0:     StackWalkInitCriticalAddress();
michael@0:     unwind_info info;
michael@0:     info.callback = aCallback;
michael@0:     info.skip = aSkipFrames + 1;
michael@0:     info.maxFrames = aMaxFrames;
michael@0:     info.numFrames = 0;
michael@0:     info.isCriticalAbort = false;
michael@0:     info.closure = aClosure;
michael@0: 
michael@0:     (void)_Unwind_Backtrace(unwind_callback, &info);
michael@0: 
michael@0:     // We ignore the return value from _Unwind_Backtrace and instead determine
michael@0:     // the outcome from |info|.  There are two main reasons for this:
michael@0:     // - On ARM/Android bionic's _Unwind_Backtrace usually (always?) returns
michael@0:     //   _URC_FAILURE.  See
michael@0:     //   https://bugzilla.mozilla.org/show_bug.cgi?id=717853#c110.
michael@0:     // - If aMaxFrames != 0, we want to stop early, and the only way to do that
michael@0:     //   is to make unwind_callback return something other than _URC_NO_REASON,
michael@0:     //   which causes _Unwind_Backtrace to return a non-success code.
michael@0:     if (info.isCriticalAbort)
michael@0:         return NS_ERROR_UNEXPECTED;
michael@0:     return info.numFrames == 0 ? NS_ERROR_FAILURE : NS_OK;
michael@0: }
michael@0: 
michael@0: #endif
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_DescribeCodeAddress(void *aPC, nsCodeAddressDetails *aDetails)
michael@0: {
michael@0:   aDetails->library[0] = '\0';
michael@0:   aDetails->loffset = 0;
michael@0:   aDetails->filename[0] = '\0';
michael@0:   aDetails->lineno = 0;
michael@0:   aDetails->function[0] = '\0';
michael@0:   aDetails->foffset = 0;
michael@0: 
michael@0:   Dl_info info;
michael@0:   int ok = dladdr(aPC, &info);
michael@0:   if (!ok) {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   PL_strncpyz(aDetails->library, info.dli_fname, sizeof(aDetails->library));
michael@0:   aDetails->loffset = (char*)aPC - (char*)info.dli_fbase;
michael@0: 
michael@0:   const char * symbol = info.dli_sname;
michael@0:   if (!symbol || symbol[0] == '\0') {
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   DemangleSymbol(symbol, aDetails->function, sizeof(aDetails->function));
michael@0: 
michael@0:   if (aDetails->function[0] == '\0') {
michael@0:     // Just use the mangled symbol if demangling failed.
michael@0:     PL_strncpyz(aDetails->function, symbol, sizeof(aDetails->function));
michael@0:   }
michael@0: 
michael@0:   aDetails->foffset = (char*)aPC - (char*)info.dli_saddr;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_FormatCodeAddressDetails(void *aPC, const nsCodeAddressDetails *aDetails,
michael@0:                             char *aBuffer, uint32_t aBufferSize)
michael@0: {
michael@0:   if (!aDetails->library[0]) {
michael@0:     snprintf(aBuffer, aBufferSize, "UNKNOWN %p\n", aPC);
michael@0:   } else if (!aDetails->function[0]) {
michael@0:     snprintf(aBuffer, aBufferSize, "UNKNOWN [%s +0x%08" PRIXPTR "]\n",
michael@0:                                    aDetails->library, aDetails->loffset);
michael@0:   } else {
michael@0:     snprintf(aBuffer, aBufferSize, "%s+0x%08" PRIXPTR
michael@0:                                    " [%s +0x%08" PRIXPTR "]\n",
michael@0:                                    aDetails->function, aDetails->foffset,
michael@0:                                    aDetails->library, aDetails->loffset);
michael@0:   }
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: #endif
michael@0: 
michael@0: #else // unsupported platform.
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_StackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:              uint32_t aMaxFrames, void *aClosure, uintptr_t aThread,
michael@0:              void *aPlatformData)
michael@0: {
michael@0:     MOZ_ASSERT(!aThread);
michael@0:     MOZ_ASSERT(!aPlatformData);
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: 
michael@0: namespace mozilla {
michael@0: nsresult
michael@0: FramePointerStackWalk(NS_WalkStackCallback aCallback, uint32_t aSkipFrames,
michael@0:                       void *aClosure, void **bp)
michael@0: {
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_DescribeCodeAddress(void *aPC, nsCodeAddressDetails *aDetails)
michael@0: {
michael@0:     aDetails->library[0] = '\0';
michael@0:     aDetails->loffset = 0;
michael@0:     aDetails->filename[0] = '\0';
michael@0:     aDetails->lineno = 0;
michael@0:     aDetails->function[0] = '\0';
michael@0:     aDetails->foffset = 0;
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: 
michael@0: EXPORT_XPCOM_API(nsresult)
michael@0: NS_FormatCodeAddressDetails(void *aPC, const nsCodeAddressDetails *aDetails,
michael@0:                             char *aBuffer, uint32_t aBufferSize)
michael@0: {
michael@0:     aBuffer[0] = '\0';
michael@0:     return NS_ERROR_NOT_IMPLEMENTED;
michael@0: }
michael@0: 
michael@0: #endif