gecko/xpcom/base/nsDebugImpl.cpp

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// Chromium headers must come before Mozilla headers.
#include "base/process_util.h"

#include "mozilla/Atomics.h"

#include "nsDebugImpl.h"
#include "nsDebug.h"
#ifdef MOZ_CRASHREPORTER
# include "nsExceptionHandler.h"
#endif
#include "nsString.h"
#include "prprf.h"
#include "prlog.h"
#include "nsError.h"
#include "prerror.h"
#include "prerr.h"
#include "prenv.h"

#ifdef ANDROID
#include <android/log.h>
#endif

#ifdef _WIN32
/* for getenv() */
#include <stdlib.h>
#endif

#include "nsTraceRefcnt.h"

#if defined(XP_UNIX)
#include <signal.h>
#endif

#if defined(XP_WIN)
#include <tchar.h>
#include "nsString.h"
#ifdef MOZ_METRO
#include "nsWindowsHelpers.h"
#endif
#endif

#if defined(XP_MACOSX)
#include <stdbool.h>
#include <unistd.h>
#include <sys/sysctl.h>
#endif

#include "mozilla/mozalloc_abort.h"

static void
Abort(const char *aMsg);

static void
RealBreak();

static void
Break(const char *aMsg);

#if defined(_WIN32)
#include <windows.h>
#include <signal.h>
#include <malloc.h> // for _alloca
#elif defined(XP_UNIX)
#include <stdlib.h>
#endif

using namespace mozilla;

static const char *sMultiprocessDescription = nullptr;

static Atomic<int32_t> gAssertionCount;

NS_IMPL_QUERY_INTERFACE2(nsDebugImpl, nsIDebug, nsIDebug2)

NS_IMETHODIMP_(MozExternalRefCountType)
nsDebugImpl::AddRef()
{
  return 2;
}

NS_IMETHODIMP_(MozExternalRefCountType)
nsDebugImpl::Release()
{
  return 1;
}

NS_IMETHODIMP
nsDebugImpl::Assertion(const char *aStr, const char *aExpr,
                       const char *aFile, int32_t aLine)
{
  NS_DebugBreak(NS_DEBUG_ASSERTION, aStr, aExpr, aFile, aLine);
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::Warning(const char *aStr, const char *aFile, int32_t aLine)
{
  NS_DebugBreak(NS_DEBUG_WARNING, aStr, nullptr, aFile, aLine);
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::Break(const char *aFile, int32_t aLine)
{
  NS_DebugBreak(NS_DEBUG_BREAK, nullptr, nullptr, aFile, aLine);
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::Abort(const char *aFile, int32_t aLine)
{
  NS_DebugBreak(NS_DEBUG_ABORT, nullptr, nullptr, aFile, aLine);
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::GetIsDebugBuild(bool* aResult)
{
#ifdef DEBUG
  *aResult = true;
#else
  *aResult = false;
#endif
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::GetAssertionCount(int32_t* aResult)
{
  *aResult = gAssertionCount;
  return NS_OK;
}

NS_IMETHODIMP
nsDebugImpl::GetIsDebuggerAttached(bool* aResult)
{
  *aResult = false;

#if defined(XP_WIN)
  *aResult = ::IsDebuggerPresent();
#elif defined(XP_MACOSX)
  // Specify the info we're looking for
  int mib[4];
  mib[0] = CTL_KERN;
  mib[1] = KERN_PROC;
  mib[2] = KERN_PROC_PID;
  mib[3] = getpid();
  size_t mibSize = sizeof(mib) / sizeof(int);

  struct kinfo_proc info;
  size_t infoSize = sizeof(info);
  memset(&info, 0, infoSize);

  if (sysctl(mib, mibSize, &info, &infoSize, nullptr, 0)) {
    // if the call fails, default to false
    *aResult = false;
    return NS_OK;
  }

  if (info.kp_proc.p_flag & P_TRACED) {
    *aResult = true;
  }
#endif

  return NS_OK;
}

/* static */ void
nsDebugImpl::SetMultiprocessMode(const char *aDesc)
{
  sMultiprocessDescription = aDesc;
}

/**
 * Implementation of the nsDebug methods. Note that this code is
 * always compiled in, in case some other module that uses it is
 * compiled with debugging even if this library is not.
 */
static PRLogModuleInfo* gDebugLog;

static void InitLog(void)
{
  if (0 == gDebugLog) {
    gDebugLog = PR_NewLogModule("nsDebug");
  }
}

enum nsAssertBehavior {
  NS_ASSERT_UNINITIALIZED,
  NS_ASSERT_WARN,
  NS_ASSERT_SUSPEND,
  NS_ASSERT_STACK,
  NS_ASSERT_TRAP,
  NS_ASSERT_ABORT,
  NS_ASSERT_STACK_AND_ABORT
};

static nsAssertBehavior GetAssertBehavior()
{
  static nsAssertBehavior gAssertBehavior = NS_ASSERT_UNINITIALIZED;
  if (gAssertBehavior != NS_ASSERT_UNINITIALIZED)
    return gAssertBehavior;

#if defined(XP_WIN) && defined(MOZ_METRO)
  if (IsRunningInWindowsMetro())
    gAssertBehavior = NS_ASSERT_WARN;
  else
    gAssertBehavior = NS_ASSERT_TRAP;
#elif defined(XP_WIN)
  gAssertBehavior = NS_ASSERT_TRAP;
#else
  gAssertBehavior = NS_ASSERT_WARN;
#endif

  const char *assertString = PR_GetEnv("XPCOM_DEBUG_BREAK");
  if (!assertString || !*assertString)
    return gAssertBehavior;

   if (!strcmp(assertString, "warn"))
     return gAssertBehavior = NS_ASSERT_WARN;

   if (!strcmp(assertString, "suspend"))
     return gAssertBehavior = NS_ASSERT_SUSPEND;

   if (!strcmp(assertString, "stack"))
     return gAssertBehavior = NS_ASSERT_STACK;

   if (!strcmp(assertString, "abort"))
     return gAssertBehavior = NS_ASSERT_ABORT;

   if (!strcmp(assertString, "trap") || !strcmp(assertString, "break"))
     return gAssertBehavior = NS_ASSERT_TRAP;

   if (!strcmp(assertString, "stack-and-abort"))
     return gAssertBehavior = NS_ASSERT_STACK_AND_ABORT;

   fprintf(stderr, "Unrecognized value of XPCOM_DEBUG_BREAK\n");
   return gAssertBehavior;
}

struct FixedBuffer
{
  FixedBuffer() : curlen(0) { buffer[0] = '\0'; }

  char buffer[1000];
  uint32_t curlen;
};

static int
StuffFixedBuffer(void *closure, const char *buf, uint32_t len)
{
  if (!len)
    return 0;
  
  FixedBuffer *fb = (FixedBuffer*) closure;

  // strip the trailing null, we add it again later
  if (buf[len - 1] == '\0')
    --len;

  if (fb->curlen + len >= sizeof(fb->buffer))
    len = sizeof(fb->buffer) - fb->curlen - 1;

  if (len) {
    memcpy(fb->buffer + fb->curlen, buf, len);
    fb->curlen += len;
    fb->buffer[fb->curlen] = '\0';
  }

  return len;
}

EXPORT_XPCOM_API(void)
NS_DebugBreak(uint32_t aSeverity, const char *aStr, const char *aExpr,
              const char *aFile, int32_t aLine)
{
   InitLog();

   FixedBuffer buf;
   PRLogModuleLevel ll = PR_LOG_WARNING;
   const char *sevString = "WARNING";

   switch (aSeverity) {
   case NS_DEBUG_ASSERTION:
     sevString = "###!!! ASSERTION";
     ll = PR_LOG_ERROR;
     break;

   case NS_DEBUG_BREAK:
     sevString = "###!!! BREAK";
     ll = PR_LOG_ALWAYS;
     break;

   case NS_DEBUG_ABORT:
     sevString = "###!!! ABORT";
     ll = PR_LOG_ALWAYS;
     break;

   default:
     aSeverity = NS_DEBUG_WARNING;
   };

#  define PrintToBuffer(...) PR_sxprintf(StuffFixedBuffer, &buf, __VA_ARGS__)

   // Print "[PID]" or "[Desc PID]" at the beginning of the message.
   PrintToBuffer("[");
   if (sMultiprocessDescription) {
     PrintToBuffer("%s ", sMultiprocessDescription);
   }
   PrintToBuffer("%d] ", base::GetCurrentProcId());

   PrintToBuffer("%s: ", sevString);

   if (aStr)
     PrintToBuffer("%s: ", aStr);

   if (aExpr)
     PrintToBuffer("'%s', ", aExpr);

   if (aFile)
     PrintToBuffer("file %s, ", aFile);

   if (aLine != -1)
     PrintToBuffer("line %d", aLine);

#  undef PrintToBuffer

   // Write out the message to the debug log
   PR_LOG(gDebugLog, ll, ("%s", buf.buffer));
   PR_LogFlush();

   // errors on platforms without a debugdlg ring a bell on stderr
#if !defined(XP_WIN)
   if (ll != PR_LOG_WARNING)
     fprintf(stderr, "\07");
#endif

#ifdef ANDROID
   __android_log_print(ANDROID_LOG_INFO, "Gecko", "%s", buf.buffer);
#endif

   // Write the message to stderr unless it's a warning and MOZ_IGNORE_WARNINGS
   // is set.
   if (!(PR_GetEnv("MOZ_IGNORE_WARNINGS") && aSeverity == NS_DEBUG_WARNING)) {
     fprintf(stderr, "%s\n", buf.buffer);
     fflush(stderr);
   }

   switch (aSeverity) {
   case NS_DEBUG_WARNING:
     return;

   case NS_DEBUG_BREAK:
     Break(buf.buffer);
     return;

   case NS_DEBUG_ABORT: {
#if defined(MOZ_CRASHREPORTER)
     nsCString note("xpcom_runtime_abort(");
     note += buf.buffer;
     note += ")";
     CrashReporter::AppendAppNotesToCrashReport(note);
     CrashReporter::AnnotateCrashReport(NS_LITERAL_CSTRING("AbortMessage"),
                                        nsDependentCString(buf.buffer));
#endif  // MOZ_CRASHREPORTER

#if defined(DEBUG) && defined(_WIN32)
     RealBreak();
#endif
#ifdef DEBUG
     nsTraceRefcnt::WalkTheStack(stderr);
#endif
     Abort(buf.buffer);
     return;
   }
   }

   // Now we deal with assertions
   gAssertionCount++;

   switch (GetAssertBehavior()) {
   case NS_ASSERT_WARN:
     return;

   case NS_ASSERT_SUSPEND:
#ifdef XP_UNIX
      fprintf(stderr, "Suspending process; attach with the debugger.\n");
      kill(0, SIGSTOP);
#else
      Break(buf.buffer);
#endif
      return;

   case NS_ASSERT_STACK:
     nsTraceRefcnt::WalkTheStack(stderr);
     return;

   case NS_ASSERT_STACK_AND_ABORT:
     nsTraceRefcnt::WalkTheStack(stderr);
     // Fall through to abort

   case NS_ASSERT_ABORT:
     Abort(buf.buffer);
     return;

   case NS_ASSERT_TRAP:
   case NS_ASSERT_UNINITIALIZED: // Default to "trap" behavior
     Break(buf.buffer);
     return;
   }   
}

static void
Abort(const char *aMsg)
{
  mozalloc_abort(aMsg);
}

static void
RealBreak()
{
#if defined(_WIN32)
  ::DebugBreak();
#elif defined(XP_MACOSX)
   raise(SIGTRAP);
#elif defined(__GNUC__) && (defined(__i386__) || defined(__i386) || defined(__x86_64__))
   asm("int $3");
#elif defined(__arm__)
   asm(
#ifdef __ARM_ARCH_4T__
/* ARMv4T doesn't support the BKPT instruction, so if the compiler target
 * is ARMv4T, we want to ensure the assembler will understand that ARMv5T
 * instruction, while keeping the resulting object tagged as ARMv4T.
 */
       ".arch armv5t\n"
       ".object_arch armv4t\n"
#endif
       "BKPT #0");
#elif defined(SOLARIS)
#if defined(__i386__) || defined(__i386) || defined(__x86_64__)
   asm("int $3");
#else
   raise(SIGTRAP);
#endif
#else
#warning do not know how to break on this platform
#endif
}

// Abort() calls this function, don't call it!
static void
Break(const char *aMsg)
{
#if defined(_WIN32)
  static int ignoreDebugger;
  if (!ignoreDebugger) {
    const char *shouldIgnoreDebugger = getenv("XPCOM_DEBUG_DLG");
    ignoreDebugger = 1 + (shouldIgnoreDebugger && !strcmp(shouldIgnoreDebugger, "1"));
  }
  if ((ignoreDebugger == 2) || !::IsDebuggerPresent()) {
    DWORD code = IDRETRY;

    /* Create the debug dialog out of process to avoid the crashes caused by 
     * Windows events leaking into our event loop from an in process dialog.
     * We do this by launching windbgdlg.exe (built in xpcom/windbgdlg).
     * See http://bugzilla.mozilla.org/show_bug.cgi?id=54792
     */
    PROCESS_INFORMATION pi;
    STARTUPINFOW si;
    wchar_t executable[MAX_PATH];
    wchar_t* pName;

    memset(&pi, 0, sizeof(pi));

    memset(&si, 0, sizeof(si));
    si.cb          = sizeof(si);
    si.wShowWindow = SW_SHOW;

    // 2nd arg of CreateProcess is in/out
    wchar_t *msgCopy = (wchar_t*) _alloca((strlen(aMsg) + 1)*sizeof(wchar_t));
    wcscpy(msgCopy, NS_ConvertUTF8toUTF16(aMsg).get());

    if(GetModuleFileNameW(GetModuleHandleW(L"xpcom.dll"), executable, MAX_PATH) &&
       nullptr != (pName = wcsrchr(executable, '\\')) &&
       nullptr != wcscpy(pName + 1, L"windbgdlg.exe") &&
       CreateProcessW(executable, msgCopy, nullptr, nullptr,
                      false, DETACHED_PROCESS | NORMAL_PRIORITY_CLASS,
                      nullptr, nullptr, &si, &pi)) {
      WaitForSingleObject(pi.hProcess, INFINITE);
      GetExitCodeProcess(pi.hProcess, &code);
      CloseHandle(pi.hProcess);
      CloseHandle(pi.hThread);
    }

    switch(code) {
    case IDABORT:
      //This should exit us
      raise(SIGABRT);
      //If we are ignored exit this way..
      _exit(3);
         
    case IDIGNORE:
      return;
    }
  }

  RealBreak();
#elif defined(XP_MACOSX)
   /* Note that we put this Mac OS X test above the GNUC/x86 test because the
    * GNUC/x86 test is also true on Intel Mac OS X and we want the PPC/x86
    * impls to be the same.
    */
   RealBreak();
#elif defined(__GNUC__) && (defined(__i386__) || defined(__i386) || defined(__x86_64__))
   RealBreak();
#elif defined(__arm__)
   RealBreak();
#elif defined(SOLARIS)
   RealBreak();
#else
#warning do not know how to break on this platform
#endif
}

static const nsDebugImpl kImpl;

nsresult
nsDebugImpl::Create(nsISupports* outer, const nsIID& aIID, void* *aInstancePtr)
{
  if (NS_WARN_IF(outer))
    return NS_ERROR_NO_AGGREGATION;

  return const_cast<nsDebugImpl*>(&kImpl)->
    QueryInterface(aIID, aInstancePtr);
}

////////////////////////////////////////////////////////////////////////////////

nsresult
NS_ErrorAccordingToNSPR()
{
    PRErrorCode err = PR_GetError();
    switch (err) {
      case PR_OUT_OF_MEMORY_ERROR:              return NS_ERROR_OUT_OF_MEMORY;
      case PR_WOULD_BLOCK_ERROR:                return NS_BASE_STREAM_WOULD_BLOCK;
      case PR_FILE_NOT_FOUND_ERROR:             return NS_ERROR_FILE_NOT_FOUND;
      case PR_READ_ONLY_FILESYSTEM_ERROR:       return NS_ERROR_FILE_READ_ONLY;
      case PR_NOT_DIRECTORY_ERROR:              return NS_ERROR_FILE_NOT_DIRECTORY;
      case PR_IS_DIRECTORY_ERROR:               return NS_ERROR_FILE_IS_DIRECTORY;
      case PR_LOOP_ERROR:                       return NS_ERROR_FILE_UNRESOLVABLE_SYMLINK;
      case PR_FILE_EXISTS_ERROR:                return NS_ERROR_FILE_ALREADY_EXISTS;
      case PR_FILE_IS_LOCKED_ERROR:             return NS_ERROR_FILE_IS_LOCKED;
      case PR_FILE_TOO_BIG_ERROR:               return NS_ERROR_FILE_TOO_BIG;
      case PR_NO_DEVICE_SPACE_ERROR:            return NS_ERROR_FILE_NO_DEVICE_SPACE;
      case PR_NAME_TOO_LONG_ERROR:              return NS_ERROR_FILE_NAME_TOO_LONG;
      case PR_DIRECTORY_NOT_EMPTY_ERROR:        return NS_ERROR_FILE_DIR_NOT_EMPTY;
      case PR_NO_ACCESS_RIGHTS_ERROR:           return NS_ERROR_FILE_ACCESS_DENIED;
      default:                                  return NS_ERROR_FAILURE;
    }
}

void
NS_ABORT_OOM(size_t size)
{
#ifdef MOZ_CRASHREPORTER
  CrashReporter::AnnotateOOMAllocationSize(size);
#endif
  MOZ_CRASH();
}