xref: /llvm-project/flang/runtime/connection.cpp (revision 8ebf741136c66f51053315bf4f0ef828c6f66094)
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 RT_OFFLOAD_API_GROUP_BEGIN
16 
RemainingSpaceInRecord() const17 RT_API_ATTRS std::size_t ConnectionState::RemainingSpaceInRecord() const {
18   auto recl{recordLength.value_or(openRecl.value_or(
19       executionEnvironment.listDirectedOutputLineLengthLimit))};
20   return positionInRecord >= recl ? 0 : recl - positionInRecord;
21 }
22 
NeedAdvance(std::size_t width) const23 RT_API_ATTRS bool ConnectionState::NeedAdvance(std::size_t width) const {
24   return positionInRecord > 0 && width > RemainingSpaceInRecord();
25 }
26 
IsAtEOF() const27 RT_API_ATTRS bool ConnectionState::IsAtEOF() const {
28   return endfileRecordNumber && currentRecordNumber >= *endfileRecordNumber;
29 }
30 
IsAfterEndfile() const31 RT_API_ATTRS bool ConnectionState::IsAfterEndfile() const {
32   return endfileRecordNumber && currentRecordNumber > *endfileRecordNumber;
33 }
34 
HandleAbsolutePosition(std::int64_t n)35 RT_API_ATTRS void ConnectionState::HandleAbsolutePosition(std::int64_t n) {
36   positionInRecord = std::max(n, std::int64_t{0}) + leftTabLimit.value_or(0);
37 }
38 
HandleRelativePosition(std::int64_t n)39 RT_API_ATTRS void ConnectionState::HandleRelativePosition(std::int64_t n) {
40   positionInRecord = std::max(leftTabLimit.value_or(0), positionInRecord + n);
41 }
42 
SavedPosition(IoStatementState & io)43 SavedPosition::SavedPosition(IoStatementState &io) : io_{io} {
44   ConnectionState &conn{io_.GetConnectionState()};
45   saved_ = conn;
46   conn.pinnedFrame = true;
47 }
48 
~SavedPosition()49 SavedPosition::~SavedPosition() {
50   if (!cancelled_) {
51     ConnectionState &conn{io_.GetConnectionState()};
52     while (conn.currentRecordNumber > saved_.currentRecordNumber) {
53       io_.BackspaceRecord();
54     }
55     conn.leftTabLimit = saved_.leftTabLimit;
56     conn.furthestPositionInRecord = saved_.furthestPositionInRecord;
57     conn.positionInRecord = saved_.positionInRecord;
58     conn.pinnedFrame = saved_.pinnedFrame;
59   }
60 }
61 
62 RT_OFFLOAD_API_GROUP_END
63 } // namespace Fortran::runtime::io
64