1 files changed, 184 insertions, 0 deletions
diff --git a/xpcom/base/nsDumpUtils.h b/xpcom/base/nsDumpUtils.h
new file mode 100644
index 0000000000..0df3fa78d6
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+++ b/xpcom/base/nsDumpUtils.h
@@ -0,0 +1,184 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_nsDumpUtils_h
+#define mozilla_nsDumpUtils_h
+
+#include "nsIObserver.h"
+#include "base/message_loop.h"
+#include "nsXULAppAPI.h"
+#include "nsThreadUtils.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/StaticPtr.h"
+#include "nsTArray.h"
+
+#ifdef LOG
+#  undef LOG
+#endif
+
+#ifdef ANDROID
+#  include "android/log.h"
+#  define LOG(...) \
+    __android_log_print(ANDROID_LOG_INFO, "Gecko:DumpUtils", ##__VA_ARGS__)
+#else
+#  define LOG(...)
+#endif
+
+#ifdef XP_UNIX  // {
+
+/**
+ * Abstract base class for something which watches an fd and takes action when
+ * we can read from it without blocking.
+ */
+class FdWatcher : public MessageLoopForIO::Watcher, public nsIObserver {
+ protected:
+  MessageLoopForIO::FileDescriptorWatcher mReadWatcher;
+  int mFd;
+
+  virtual ~FdWatcher() {
+    // StopWatching should have run.
+    MOZ_ASSERT(mFd == -1);
+  }
+
+ public:
+  FdWatcher() : mFd(-1) { MOZ_ASSERT(NS_IsMainThread()); }
+
+  /**
+   * Open the fd to watch.  If we encounter an error, return -1.
+   */
+  virtual int OpenFd() = 0;
+
+  /**
+   * Called when you can read() from the fd without blocking.  Note that this
+   * function is also called when you're at eof (read() returns 0 in this case).
+   */
+  virtual void OnFileCanReadWithoutBlocking(int aFd) override = 0;
+  virtual void OnFileCanWriteWithoutBlocking(int aFd) override{};
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  /**
+   * Initialize this object.  This should be called right after the object is
+   * constructed.  (This would go in the constructor, except we interact with
+   * XPCOM, which we can't do from a constructor because our refcount is 0 at
+   * that point.)
+   */
+  void Init();
+
+  // Implementations may call this function multiple times if they ensure that
+
+  virtual void StartWatching();
+
+  // Since implementations can call StartWatching() multiple times, they can of
+  // course call StopWatching() multiple times.
+  virtual void StopWatching();
+
+  NS_IMETHOD Observe(nsISupports* aSubject, const char* aTopic,
+                     const char16_t* aData) override {
+    MOZ_ASSERT(NS_IsMainThread());
+    MOZ_ASSERT(!strcmp(aTopic, "xpcom-shutdown"));
+
+    XRE_GetIOMessageLoop()->PostTask(mozilla::NewRunnableMethod(
+        "FdWatcher::StopWatching", this, &FdWatcher::StopWatching));
+
+    return NS_OK;
+  }
+};
+
+typedef void (*FifoCallback)(const nsCString& aInputStr);
+struct FifoInfo {
+  nsCString mCommand;
+  FifoCallback mCallback;
+};
+typedef nsTArray<FifoInfo> FifoInfoArray;
+
+class FifoWatcher : public FdWatcher {
+ public:
+  /**
+   * The name of the preference used to enable/disable the FifoWatcher.
+   */
+  // The length of this array must match the size of the string constant in
+  // the definition in nsDumpUtils.cpp. A mismatch will result in a compile-time
+  // error.
+  static const char kPrefName[38];
+
+  static FifoWatcher* GetSingleton();
+
+  static bool MaybeCreate();
+
+  void RegisterCallback(const nsCString& aCommand, FifoCallback aCallback);
+
+  virtual ~FifoWatcher();
+
+  virtual int OpenFd() override;
+
+  virtual void OnFileCanReadWithoutBlocking(int aFd) override;
+
+ private:
+  nsAutoCString mDirPath;
+
+  static mozilla::StaticRefPtr<FifoWatcher> sSingleton;
+
+  explicit FifoWatcher(nsCString aPath)
+      : mDirPath(aPath), mFifoInfoLock("FifoWatcher.mFifoInfoLock") {}
+
+  mozilla::Mutex mFifoInfoLock;  // protects mFifoInfo
+  FifoInfoArray mFifoInfo;
+};
+
+typedef void (*PipeCallback)(const uint8_t aRecvSig);
+struct SignalInfo {
+  uint8_t mSignal;
+  PipeCallback mCallback;
+};
+typedef nsTArray<SignalInfo> SignalInfoArray;
+
+class SignalPipeWatcher : public FdWatcher {
+ public:
+  static SignalPipeWatcher* GetSingleton();
+
+  void RegisterCallback(uint8_t aSignal, PipeCallback aCallback);
+
+  void RegisterSignalHandler(uint8_t aSignal = 0);
+
+  virtual ~SignalPipeWatcher();
+
+  virtual int OpenFd() override;
+
+  virtual void StopWatching() override;
+
+  virtual void OnFileCanReadWithoutBlocking(int aFd) override;
+
+ private:
+  static mozilla::StaticRefPtr<SignalPipeWatcher> sSingleton;
+
+  SignalPipeWatcher() : mSignalInfoLock("SignalPipeWatcher.mSignalInfoLock") {
+    MOZ_ASSERT(NS_IsMainThread());
+  }
+
+  mozilla::Mutex mSignalInfoLock;  // protects mSignalInfo
+  SignalInfoArray mSignalInfo;
+};
+
+#endif  // XP_UNIX }
+
+class nsDumpUtils {
+ public:
+  enum Mode { CREATE, CREATE_UNIQUE };
+
+  /**
+   * This function creates a new unique file based on |aFilename| in a
+   * world-readable temp directory. This is the system temp directory
+   * or, in the case of Android, the downloads directory. If |aFile| is
+   * non-null, it is assumed to point to a folder, and that folder is used
+   * instead.
+   */
+  static nsresult OpenTempFile(const nsACString& aFilename, nsIFile** aFile,
+                               const nsACString& aFoldername = ""_ns,
+                               Mode aMode = CREATE_UNIQUE);
+};
+
+#endif