DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (014c61389f0b)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144
/* -*- Mode: C++; tab-width: 2; 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/. */

#include <stdio.h>
#ifdef XP_WIN
#  include <process.h>
#  define getpid _getpid
#else
#  include <signal.h>
#  include <unistd.h>
#endif
#include "mozilla/dom/ScriptSettings.h"  // for AutoJSAPI
#include "mozilla/CodeCoverageHandler.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/DebugOnly.h"
#include "nsAppRunner.h"
#include "nsIOutputStream.h"
#include "nsNetUtil.h"
#include "nsPrintfCString.h"
#include "prtime.h"

using namespace mozilla;

// The __gcov_flush function writes the coverage counters to gcda files and then
// resets them to zero. It is defined at
// https://github.com/gcc-mirror/gcc/blob/aad93da1a579b9ae23ede6b9cf8523360f0a08b4/libgcc/libgcov-interface.c.
// __gcov_flush is protected by a mutex in GCC, but not in LLVM, so we are using
// a CrossProcessMutex to protect it.

// We rename __gcov_flush to __custom_llvm_gcov_flush in our build of LLVM for
// Linux, to avoid naming clashes in builds which mix GCC and LLVM. So, when we
// are building with LLVM exclusively, we need to use __custom_llvm_gcov_flush
// instead.
#if !defined(XP_WIN) && defined(__clang__)
#  define __gcov_flush __custom_llvm_gcov_flush
#endif

extern "C" void __gcov_flush();

StaticAutoPtr<CodeCoverageHandler> CodeCoverageHandler::instance;

void CodeCoverageHandler::FlushCounters() {
  printf_stderr("[CodeCoverage] Requested flush for %d.\n", getpid());

  CrossProcessMutexAutoLock lock(*CodeCoverageHandler::Get()->GetMutex());

  __gcov_flush();

  printf_stderr("[CodeCoverage] flush completed.\n");

  const char* outDir = getenv("JS_CODE_COVERAGE_OUTPUT_DIR");
  if (!outDir || *outDir == 0) {
    return;
  }

  dom::AutoJSAPI jsapi;
  jsapi.Init();
  size_t length;
  JS::UniqueChars result = js::GetCodeCoverageSummaryAll(jsapi.cx(), &length);
  if (!result) {
    return;
  }

  nsCOMPtr<nsIFile> file;

  nsresult rv = NS_NewNativeLocalFile(nsDependentCString(outDir), false,
                                      getter_AddRefs(file));
  MOZ_ASSERT(NS_SUCCEEDED(rv));

  rv = file->AppendNative(
      nsPrintfCString("%lu-%d.info", PR_Now() / PR_USEC_PER_MSEC, getpid()));

  rv = file->CreateUnique(nsIFile::NORMAL_FILE_TYPE, 0666);
  MOZ_ASSERT(NS_SUCCEEDED(rv));

  nsCOMPtr<nsIOutputStream> outputStream;
  rv = NS_NewLocalFileOutputStream(getter_AddRefs(outputStream), file);
  MOZ_ASSERT(NS_SUCCEEDED(rv));

  char* data = result.get();
  while (length) {
    uint32_t n = 0;
    rv = outputStream->Write(data, length, &n);
    MOZ_ASSERT(NS_SUCCEEDED(rv));
    data += n;
    length -= n;
  }

  rv = outputStream->Close();
  MOZ_ASSERT(NS_SUCCEEDED(rv));

  printf_stderr("[CodeCoverage] JS flush completed.\n");
}

void CodeCoverageHandler::FlushCountersSignalHandler(int) { FlushCounters(); }

void CodeCoverageHandler::SetSignalHandlers() {
#ifndef XP_WIN
  printf_stderr("[CodeCoverage] Setting handlers for process %d.\n", getpid());

  struct sigaction dump_sa;
  dump_sa.sa_handler = CodeCoverageHandler::FlushCountersSignalHandler;
  dump_sa.sa_flags = SA_RESTART;
  sigemptyset(&dump_sa.sa_mask);
  DebugOnly<int> r1 = sigaction(SIGUSR1, &dump_sa, nullptr);
  MOZ_ASSERT(r1 == 0, "Failed to install GCOV SIGUSR1 handler");
#endif
}

CodeCoverageHandler::CodeCoverageHandler() : mGcovLock("GcovLock") {
  SetSignalHandlers();
}

CodeCoverageHandler::CodeCoverageHandler(const CrossProcessMutexHandle& aHandle)
    : mGcovLock(aHandle) {
  SetSignalHandlers();
}

void CodeCoverageHandler::Init() {
  MOZ_ASSERT(!instance);
  MOZ_ASSERT(XRE_IsParentProcess());
  instance = new CodeCoverageHandler();
  ClearOnShutdown(&instance);
}

void CodeCoverageHandler::Init(const CrossProcessMutexHandle& aHandle) {
  MOZ_ASSERT(!instance);
  MOZ_ASSERT(!XRE_IsParentProcess());
  instance = new CodeCoverageHandler(aHandle);
  ClearOnShutdown(&instance);
}

CodeCoverageHandler* CodeCoverageHandler::Get() {
  MOZ_ASSERT(instance);
  return instance;
}

CrossProcessMutex* CodeCoverageHandler::GetMutex() { return &mGcovLock; }

CrossProcessMutexHandle CodeCoverageHandler::GetMutexHandle(int aProcId) {
  return mGcovLock.ShareToProcess(aProcId);
}