tools/code-coverage/nsCodeCoverage.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   4  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsCodeCoverage.h"
   7 #include "mozilla/CodeCoverageHandler.h"
   8 #include "mozilla/Unused.h"
   9 #include "mozilla/dom/ContentParent.h"
  10 #include "mozilla/dom/Promise.h"
  11
  12 using namespace mozilla;
  13 using namespace mozilla::dom;
  14 using namespace mozilla::ipc;
  15
  16 NS_IMPL_ISUPPORTS(nsCodeCoverage, nsICodeCoverage)
  17
  18 nsCodeCoverage::nsCodeCoverage() {}
  19
  20 nsCodeCoverage::~nsCodeCoverage() {}
  21
  22 enum RequestType { Flush };
  23
  24 class ProcessCount final {
  25   NS_INLINE_DECL_REFCOUNTING(ProcessCount);
  26
  27  public:
  28   explicit ProcessCount(uint32_t c) : mCount(c) {}
  29   operator uint32_t() const { return mCount; }
  30   ProcessCount& operator--() {
  31     mCount--;
  32     return *this;
  33   }
  34
  35  private:
  36   ~ProcessCount() {}
  37   uint32_t mCount;
  38 };
  39
  40 nsresult Request(JSContext* cx, Promise** aPromise, RequestType requestType) {
  41   MOZ_ASSERT(XRE_IsParentProcess());
  42   MOZ_ASSERT(NS_IsMainThread());
  43
  44   nsIGlobalObject* global = xpc::CurrentNativeGlobal(cx);
  45   if (NS_WARN_IF(!global)) {
  46     return NS_ERROR_FAILURE;
  47   }
  48
  49   ErrorResult result;
  50   RefPtr<Promise> promise = Promise::Create(global, result);
  51   if (NS_WARN_IF(result.Failed())) {
  52     return result.StealNSResult();
  53   }
  54
  55   uint32_t processCount = 0;
  56   for (auto* cp : ContentParent::AllProcesses(ContentParent::eLive)) {
  57     Unused << cp;
  58     ++processCount;
  59   }
  60
  61   if (requestType == RequestType::Flush) {
  62     CodeCoverageHandler::FlushCounters();
  63   }
  64
  65   if (processCount == 0) {
  66     promise->MaybeResolveWithUndefined();
  67   } else {
  68     RefPtr<ProcessCount> processCountHolder(new ProcessCount(processCount));
  69
  70     auto resolve = [processCountHolder, promise](bool unused) {
  71       if (--(*processCountHolder) == 0) {
  72         promise->MaybeResolveWithUndefined();
  73       }
  74     };
  75
  76     auto reject = [promise](ResponseRejectReason&& aReason) {
  77       promise->MaybeReject(NS_ERROR_FAILURE);
  78     };
  79
  80     for (auto* cp : ContentParent::AllProcesses(ContentParent::eLive)) {
  81       if (requestType == RequestType::Flush) {
  82         cp->SendFlushCodeCoverageCounters(resolve, reject);
  83       }
  84     }
  85   }
  86
  87   promise.forget(aPromise);
  88   return NS_OK;
  89 }
  90
  91 NS_IMETHODIMP nsCodeCoverage::FlushCounters(JSContext* cx, Promise** aPromise) {
  92   return Request(cx, aPromise, RequestType::Flush);
  93 }