flang/runtime/connection.cpp

   1 //===-- runtime/connection.cpp --------------------------------------------===//
   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 #include "connection.h"
  10 #include "environment.h"
  11 #include "io-stmt.h"
  12 #include <algorithm>
  13
  14 namespace Fortran::runtime::io {
  15
  16 std::size_t ConnectionState::RemainingSpaceInRecord() const {
  17   auto recl{recordLength.value_or(openRecl.value_or(
  18       executionEnvironment.listDirectedOutputLineLengthLimit))};
  19   return positionInRecord >= recl ? 0 : recl - positionInRecord;
  20 }
  21
  22 bool ConnectionState::NeedAdvance(std::size_t width) const {
  23   return positionInRecord > 0 && width > RemainingSpaceInRecord();
  24 }
  25
  26 bool ConnectionState::IsAtEOF() const {
  27   return endfileRecordNumber && currentRecordNumber >= *endfileRecordNumber;
  28 }
  29
  30 bool ConnectionState::IsAfterEndfile() const {
  31   return endfileRecordNumber && currentRecordNumber > *endfileRecordNumber;
  32 }
  33
  34 void ConnectionState::HandleAbsolutePosition(std::int64_t n) {
  35   positionInRecord = std::max(n, std::int64_t{0}) + leftTabLimit.value_or(0);
  36 }
  37
  38 void ConnectionState::HandleRelativePosition(std::int64_t n) {
  39   positionInRecord = std::max(leftTabLimit.value_or(0), positionInRecord + n);
  40 }
  41
  42 SavedPosition::SavedPosition(IoStatementState &io) : io_{io} {
  43   ConnectionState &conn{io_.GetConnectionState()};
  44   saved_ = conn;
  45   conn.pinnedFrame = true;
  46 }
  47
  48 SavedPosition::~SavedPosition() {
  49   ConnectionState &conn{io_.GetConnectionState()};
  50   while (conn.currentRecordNumber > saved_.currentRecordNumber) {
  51     io_.BackspaceRecord();
  52   }
  53   conn.leftTabLimit = saved_.leftTabLimit;
  54   conn.furthestPositionInRecord = saved_.furthestPositionInRecord;
  55   conn.positionInRecord = saved_.positionInRecord;
  56   conn.pinnedFrame = saved_.pinnedFrame;
  57 }
  58 } // namespace Fortran::runtime::io