//===- EPCGenericDylibManager.h -- Generic EPC Dylib management -*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Implements dylib loading and searching by making calls to
// ExecutorProcessControl::callWrapper.
//
// This simplifies the implementaton of new ExecutorProcessControl instances,
// as this implementation will always work (at the cost of some performance
// overhead for the calls).
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_EXECUTIONENGINE_ORC_EPCGENERICDYLIBMANAGER_H
#define LLVM_EXECUTIONENGINE_ORC_EPCGENERICDYLIBMANAGER_H

#include "llvm/ExecutionEngine/Orc/DylibManager.h"
#include "llvm/ExecutionEngine/Orc/ExecutorProcessControl.h"
#include "llvm/ExecutionEngine/Orc/Shared/ExecutorSymbolDef.h"
#include "llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h"
#include "llvm/ExecutionEngine/Orc/Shared/SimpleRemoteEPCUtils.h"
#include "llvm/Support/Compiler.h"

namespace llvm {
namespace orc {

class JITDylib;
class SymbolLookupSet;

class LLVM_ABI EPCGenericDylibManager : public DylibManager {
public:
  /// Function addresses for memory access.
  struct SymbolAddrs {
    ExecutorAddr Instance;
    ExecutorAddr Open;
    ExecutorAddr Resolve;
  };

  /// Create an EPCGenericDylibManager instance by looking up the LLVM-style
  /// SimpleExecutorDylibManager symbol names in the EPC's bootstrap table.
  static Expected<EPCGenericDylibManager>
  CreateWithDefaultBootstrapSymbols(ExecutorProcessControl &EPC);

  /// Create an EPCGenericDylibManager using the given implementation symbol
  /// names. These will be looked up in the given JITDylib.
  static Expected<EPCGenericDylibManager>
  Create(JITDylib &JD, rt::SimpleExecutorDylibManagerSymbolNames SNs =
                           rt::orc_rt_NativeDylibManagerSPSSymbols);

  /// Create an EPCGenericDylibManager using the given implementation symbol
  /// names. These will be looked up in the given ExecutionSession's bootstrap
  /// JITDylib.
  static Expected<EPCGenericDylibManager>
  Create(ExecutionSession &ES, rt::SimpleExecutorDylibManagerSymbolNames SNs =
                                   rt::orc_rt_NativeDylibManagerSPSSymbols);

  /// Create an EPCGenericDylibManager instance from a given set of function
  /// addrs.
  EPCGenericDylibManager(ExecutorProcessControl &EPC, SymbolAddrs SAs)
      : EPC(EPC), SAs(SAs) {}

  /// Loads the dylib with the given name.
  Expected<tpctypes::DylibHandle> open(StringRef Path, uint64_t Mode);

  /// Looks up symbols within the given dylib.
  Expected<tpctypes::LookupResult> lookup(tpctypes::DylibHandle H,
                                          const SymbolLookupSet &Lookup) {
    std::promise<MSVCPExpected<tpctypes::LookupResult>> RP;
    auto RF = RP.get_future();
    lookupAsync(H, Lookup, [&RP](auto R) { RP.set_value(std::move(R)); });
    return RF.get();
  }

  /// Looks up symbols within the given dylib.
  Expected<tpctypes::LookupResult> lookup(tpctypes::DylibHandle H,
                                          const RemoteSymbolLookupSet &Lookup) {
    std::promise<MSVCPExpected<tpctypes::LookupResult>> RP;
    auto RF = RP.get_future();
    lookupAsync(H, Lookup, [&RP](auto R) { RP.set_value(std::move(R)); });
    return RF.get();
  }

  using SymbolLookupCompleteFn =
      unique_function<void(Expected<tpctypes::LookupResult>)>;

  /// Looks up symbols within the given dylib.
  void lookupAsync(tpctypes::DylibHandle H, const SymbolLookupSet &Lookup,
                   SymbolLookupCompleteFn Complete);

  /// Looks up symbols within the given dylib.
  void lookupAsync(tpctypes::DylibHandle H, const RemoteSymbolLookupSet &Lookup,
                   SymbolLookupCompleteFn Complete);

  /// Load the dynamic library at the given path and return a handle to it.
  /// If DylibPath is null this function will return the global handle for
  /// the target process.
  Expected<tpctypes::DylibHandle> loadDylib(const char *DylibPath) override;

  /// Search for symbols in the target process.
  void
  lookupSymbolsAsync(tpctypes::DylibHandle H, const SymbolLookupSet &Symbols,
                     DylibManager::SymbolLookupCompleteFn Complete) override;

private:
  ExecutorProcessControl &EPC;
  SymbolAddrs SAs;
};

} // end namespace orc
} // end namespace llvm

#endif // LLVM_EXECUTIONENGINE_ORC_EPCGENERICDYLIBMANAGER_H