jsshell.h

/* -*- 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 jsshell_js_h
#define jsshell_js_h

#include "mozilla/Atomics.h"
#include "mozilla/Maybe.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/Variant.h"

#include "jsapi.h"

#include "builtin/MapObject.h"
#include "js/GCVector.h"
#include "threading/ConditionVariable.h"
#include "threading/LockGuard.h"
#include "threading/Mutex.h"
#include "threading/Thread.h"
#include "vm/GeckoProfiler.h"
#include "vm/Monitor.h"

// Some platform hooks must be implemented for single-step profiling.
#if defined(JS_SIMULATOR_ARM) || defined(JS_SIMULATOR_MIPS64) || \
    defined(JS_SIMULATOR_MIPS32)
#  define SINGLESTEP_PROFILING
#endif

namespace js {
namespace shell {

enum JSShellErrNum {
#define MSG_DEF(name, count, exception, format) name,
#include "jsshell.msg"
#undef MSG_DEF
  JSShellErr_Limit
};

const JSErrorFormatString* my_GetErrorMessage(void* userRef,
                                              const unsigned errorNumber);

void WarningReporter(JSContext* cx, JSErrorReport* report);

class MOZ_STACK_CLASS AutoReportException {
  JSContext* cx;

 public:
  explicit AutoReportException(JSContext* cx) : cx(cx) {}
  ~AutoReportException();
};

bool GenerateInterfaceHelp(JSContext* cx, JS::HandleObject obj,
                           const char* name);

JSString* FileAsString(JSContext* cx, JS::HandleString pathnameStr);

class AutoCloseFile {
 private:
  FILE* f_;

 public:
  explicit AutoCloseFile(FILE* f) : f_(f) {}
  ~AutoCloseFile() { (void)release(); }
  bool release() {
    bool success = true;
    if (f_ && f_ != stdin && f_ != stdout && f_ != stderr) {
      success = !fclose(f_);
    }
    f_ = nullptr;
    return success;
  }
};

// Reference counted file.
struct RCFile {
  FILE* fp;
  uint32_t numRefs;

  RCFile() : fp(nullptr), numRefs(0) {}
  explicit RCFile(FILE* fp) : fp(fp), numRefs(0) {}

  void acquire() { numRefs++; }

  // Starts out with a ref count of zero.
  static RCFile* create(JSContext* cx, const char* filename, const char* mode);

  void close();
  bool isOpen() const { return fp; }
  bool release();
};

// Alias the global dstName to namespaceObj.srcName. For example, if dstName is
// "snarf", namespaceObj represents "os.file", and srcName is "readFile", then
// this is equivalent to the JS code:
//
//   snarf = os.file.readFile;
//
// This provides a mechanism for namespacing the various JS shell helper
// functions without breaking backwards compatibility with things that use the
// global names.
bool CreateAlias(JSContext* cx, const char* dstName,
                 JS::HandleObject namespaceObj, const char* srcName);

enum class ScriptKind { Script, DecodeScript, Module };

class NonshrinkingGCObjectVector
    : public GCVector<JSObject*, 0, SystemAllocPolicy> {
 public:
  void sweep() {
    for (uint32_t i = 0; i < this->length(); i++) {
      if (JS::GCPolicy<JSObject*>::needsSweep(&(*this)[i])) {
        (*this)[i] = nullptr;
      }
    }
  }
};

using MarkBitObservers = JS::WeakCache<NonshrinkingGCObjectVector>;

#ifdef SINGLESTEP_PROFILING
using StackChars = Vector<char16_t, 0, SystemAllocPolicy>;
#endif

class OffThreadJob;

// Per-context shell state.
struct ShellContext {
  explicit ShellContext(JSContext* cx);
  ~ShellContext();

  bool isWorker;
  bool lastWarningEnabled;

  // Track promise rejections and report unhandled rejections.
  bool trackUnhandledRejections;

  double timeoutInterval;
  double startTime;
  mozilla::Atomic<bool> serviceInterrupt;
  mozilla::Atomic<bool> haveInterruptFunc;
  JS::PersistentRootedValue interruptFunc;
  JS::PersistentRootedValue lastWarning;
  JS::PersistentRootedValue promiseRejectionTrackerCallback;

  // Rejected promises that are not yet handled. Added when rejection
  // happens, and removed when rejection is handled. This uses SetObject to
  // report unhandled rejections in the rejected order.
  JS::PersistentRooted<SetObject*> unhandledRejectedPromises;

#ifdef SINGLESTEP_PROFILING
  Vector<StackChars, 0, SystemAllocPolicy> stacks;
#endif

  /*
   * Watchdog thread state.
   */
  js::Mutex watchdogLock;
  js::ConditionVariable watchdogWakeup;
  mozilla::Maybe<js::Thread> watchdogThread;
  mozilla::Maybe<mozilla::TimeStamp> watchdogTimeout;

  js::ConditionVariable sleepWakeup;

  int exitCode;
  bool quitting;

  JS::UniqueChars readLineBuf;
  size_t readLineBufPos;

  js::shell::RCFile** errFilePtr;
  js::shell::RCFile** outFilePtr;

  UniquePtr<ProfilingStack> geckoProfilingStack;

  JS::UniqueChars moduleLoadPath;

  UniquePtr<MarkBitObservers> markObservers;

  // Off-thread parse state.
  js::Monitor offThreadMonitor;
  Vector<OffThreadJob*, 0, SystemAllocPolicy> offThreadJobs;
};

extern ShellContext* GetShellContext(JSContext* cx);

} /* namespace shell */
} /* namespace js */

#endif