flang/runtime/internal-unit.h

   1 //===-- runtime/internal-unit.h ---------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // Fortran internal I/O "units"
  10
  11 #ifndef FORTRAN_RUNTIME_IO_INTERNAL_UNIT_H_
  12 #define FORTRAN_RUNTIME_IO_INTERNAL_UNIT_H_
  13
  14 #include "connection.h"
  15 #include "flang/Runtime/descriptor.h"
  16 #include <cinttypes>
  17 #include <type_traits>
  18
  19 namespace Fortran::runtime::io {
  20
  21 class IoErrorHandler;
  22
  23 // Points to (but does not own) a CHARACTER scalar or array for internal I/O.
  24 // Does not buffer.
  25 template <Direction DIR> class InternalDescriptorUnit : public ConnectionState {
  26 public:
  27   using Scalar =
  28       std::conditional_t<DIR == Direction::Input, const char *, char *>;
  29   InternalDescriptorUnit(Scalar, std::size_t chars, int kind);
  30   InternalDescriptorUnit(const Descriptor &, const Terminator &);
  31   void EndIoStatement();
  32
  33   bool Emit(const char *, std::size_t, IoErrorHandler &);
  34   std::size_t GetNextInputBytes(const char *&, IoErrorHandler &);
  35   bool AdvanceRecord(IoErrorHandler &);
  36   void BackspaceRecord(IoErrorHandler &);
  37   std::int64_t InquirePos();
  38
  39 private:
  40   Descriptor &descriptor() { return staticDescriptor_.descriptor(); }
  41   const Descriptor &descriptor() const {
  42     return staticDescriptor_.descriptor();
  43   }
  44   Scalar CurrentRecord() const {
  45     return descriptor().template ZeroBasedIndexedElement<char>(
  46         currentRecordNumber - 1);
  47   }
  48   void BlankFill(char *, std::size_t);
  49   void BlankFillOutputRecord();
  50
  51   StaticDescriptor<maxRank, true /*addendum*/> staticDescriptor_;
  52 };
  53
  54 extern template class InternalDescriptorUnit<Direction::Output>;
  55 extern template class InternalDescriptorUnit<Direction::Input>;
  56 } // namespace Fortran::runtime::io
  57 #endif // FORTRAN_RUNTIME_IO_INTERNAL_UNIT_H_