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 mozilla::dom::ContentParent;
  13 using mozilla::dom::Promise;
  14
  15 NS_IMPL_ISUPPORTS(nsCodeCoverage, nsICodeCoverage)
  16
  17 nsCodeCoverage::nsCodeCoverage() {}
  18
  19 nsCodeCoverage::~nsCodeCoverage() {}
  20
  21 enum RequestType { Flush };
  22
  23 class ProcessCount final {
  24   NS_INLINE_DECL_REFCOUNTING(ProcessCount);
  25
  26  public:
  27   explicit ProcessCount(uint32_t c) : mCount(c) {}
  28   operator uint32_t() const { return mCount; }
  29   ProcessCount& operator--() {
  30     mCount--;
  31     return *this;
  32   }
  33
  34  private:
  35   ~ProcessCount() {}
  36   uint32_t mCount;
  37 };
  38
  39 namespace {
  40
  41 nsresult Request(JSContext* cx, Promise** aPromise, RequestType requestType) {
  42   MOZ_ASSERT(XRE_IsParentProcess());
  43   MOZ_ASSERT(NS_IsMainThread());
  44
  45   nsIGlobalObject* global = xpc::CurrentNativeGlobal(cx);
  46   if (NS_WARN_IF(!global)) {
  47     return NS_ERROR_FAILURE;
  48   }
  49
  50   mozilla::ErrorResult result;
  51   RefPtr<Promise> promise = Promise::Create(global, result);
  52   if (NS_WARN_IF(result.Failed())) {
  53     return result.StealNSResult();
  54   }
  55
  56   uint32_t processCount = 0;
  57   for (auto* cp : ContentParent::AllProcesses(ContentParent::eLive)) {
  58     mozilla::Unused << cp;
  59     ++processCount;
  60   }
  61
  62   if (requestType == RequestType::Flush) {
  63     mozilla::CodeCoverageHandler::FlushCounters();
  64   }
  65
  66   if (processCount == 0) {
  67     promise->MaybeResolveWithUndefined();
  68   } else {
  69     RefPtr<ProcessCount> processCountHolder(new ProcessCount(processCount));
  70
  71     auto resolve = [processCountHolder, promise](bool unused) {
  72       if (--(*processCountHolder) == 0) {
  73         promise->MaybeResolveWithUndefined();
  74       }
  75     };
  76
  77     auto reject = [promise](mozilla::ipc::ResponseRejectReason&& aReason) {
  78       promise->MaybeReject(NS_ERROR_FAILURE);
  79     };
  80
  81     for (auto* cp : ContentParent::AllProcesses(ContentParent::eLive)) {
  82       if (requestType == RequestType::Flush) {
  83         cp->SendFlushCodeCoverageCounters(resolve, reject);
  84       }
  85     }
  86   }
  87
  88   promise.forget(aPromise);
  89   return NS_OK;
  90 }
  91
  92 }  // anonymous namespace
  93
  94 NS_IMETHODIMP nsCodeCoverage::FlushCounters(JSContext* cx, Promise** aPromise) {
  95   return Request(cx, aPromise, RequestType::Flush);
  96 }