37f98f6f4c
Add a isFixedRecordLength flag member to Connection to disambiguate the state of "record has known variable length" from "record has fixed length". Code that sets and tests this flag will appear in later patches. Rearrange data members to reduce storage requirements, since Connection might indirectly end up on a program stack frame. Add a utility member function BeginRecord(); use it in internal I/O processing. Reviewed By: tskeith, sscalpone Differential Revision: https://reviews.llvm.org/D83098
65 lines
2.4 KiB
C++
65 lines
2.4 KiB
C++
//===-- runtime/connection.h ------------------------------------*- 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
// Fortran I/O connection state (abstracted over internal & external units)
|
|
|
|
#ifndef FORTRAN_RUNTIME_IO_CONNECTION_H_
|
|
#define FORTRAN_RUNTIME_IO_CONNECTION_H_
|
|
|
|
#include "format.h"
|
|
#include <cinttypes>
|
|
#include <optional>
|
|
|
|
namespace Fortran::runtime::io {
|
|
|
|
enum class Direction { Output, Input };
|
|
enum class Access { Sequential, Direct, Stream };
|
|
|
|
inline bool IsRecordFile(Access a) { return a != Access::Stream; }
|
|
|
|
// These characteristics of a connection are immutable after being
|
|
// established in an OPEN statement.
|
|
struct ConnectionAttributes {
|
|
Access access{Access::Sequential}; // ACCESS='SEQUENTIAL', 'DIRECT', 'STREAM'
|
|
bool isUnformatted{false}; // FORM='UNFORMATTED'
|
|
bool isUTF8{false}; // ENCODING='UTF-8'
|
|
bool isFixedRecordLength{false}; // RECL= on OPEN
|
|
std::optional<std::int64_t> recordLength; // RECL= or current record
|
|
};
|
|
|
|
struct ConnectionState : public ConnectionAttributes {
|
|
bool IsAtEOF() const; // true when read has hit EOF or endfile record
|
|
std::size_t RemainingSpaceInRecord() const;
|
|
void HandleAbsolutePosition(std::int64_t);
|
|
void HandleRelativePosition(std::int64_t);
|
|
|
|
void BeginRecord() {
|
|
positionInRecord = 0;
|
|
furthestPositionInRecord = 0;
|
|
leftTabLimit.reset();
|
|
}
|
|
|
|
// Positions in a record file (sequential or direct, not stream)
|
|
std::int64_t currentRecordNumber{1}; // 1 is first
|
|
std::int64_t positionInRecord{0}; // offset in current record
|
|
std::int64_t furthestPositionInRecord{0}; // max(position+bytes)
|
|
bool nonAdvancing{false}; // ADVANCE='NO'
|
|
|
|
// Set at end of non-advancing I/O data transfer
|
|
std::optional<std::int64_t> leftTabLimit; // offset in current record
|
|
|
|
// currentRecordNumber value captured after ENDFILE/REWIND/BACKSPACE statement
|
|
// or an end-of-file READ condition on a sequential access file
|
|
std::optional<std::int64_t> endfileRecordNumber;
|
|
|
|
// Mutable modes set at OPEN() that can be overridden in READ/WRITE & FORMAT
|
|
MutableModes modes; // BLANK=, DECIMAL=, SIGN=, ROUND=, PAD=, DELIM=, kP
|
|
};
|
|
} // namespace Fortran::runtime::io
|
|
#endif // FORTRAN_RUNTIME_IO_CONNECTION_H_
|