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|
//===-- runtime/unit.cpp --------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Implementation of ExternalFileUnit common for both
// RT_USE_PSEUDO_FILE_UNIT=0 and RT_USE_PSEUDO_FILE_UNIT=1.
//
//===----------------------------------------------------------------------===//
#include "unit.h"
#include "io-error.h"
#include "lock.h"
#include "tools.h"
#include <limits>
#include <utility>
namespace Fortran::runtime::io {
RT_OFFLOAD_VAR_GROUP_BEGIN
RT_VAR_ATTRS ExternalFileUnit *defaultInput{nullptr}; // unit 5
RT_VAR_ATTRS ExternalFileUnit *defaultOutput{nullptr}; // unit 6
RT_VAR_ATTRS ExternalFileUnit *errorOutput{nullptr}; // unit 0 extension
RT_OFFLOAD_VAR_GROUP_END
RT_OFFLOAD_API_GROUP_BEGIN
static inline RT_API_ATTRS void SwapEndianness(
char *data, std::size_t bytes, std::size_t elementBytes) {
if (elementBytes > 1) {
auto half{elementBytes >> 1};
for (std::size_t j{0}; j + elementBytes <= bytes; j += elementBytes) {
for (std::size_t k{0}; k < half; ++k) {
RT_DIAG_PUSH
RT_DIAG_DISABLE_CALL_HOST_FROM_DEVICE_WARN
std::swap(data[j + k], data[j + elementBytes - 1 - k]);
RT_DIAG_POP
}
}
}
}
bool ExternalFileUnit::Emit(const char *data, std::size_t bytes,
std::size_t elementBytes, IoErrorHandler &handler) {
auto furthestAfter{std::max(furthestPositionInRecord,
positionInRecord + static_cast<std::int64_t>(bytes))};
if (openRecl) {
// Check for fixed-length record overrun, but allow for
// sequential record termination.
int extra{0};
int header{0};
if (access == Access::Sequential) {
if (isUnformatted.value_or(false)) {
// record header + footer
header = static_cast<int>(sizeof(std::uint32_t));
extra = 2 * header;
} else {
#ifdef _WIN32
if (!isWindowsTextFile()) {
++extra; // carriage return (CR)
}
#endif
++extra; // newline (LF)
}
}
if (furthestAfter > extra + *openRecl) {
handler.SignalError(IostatRecordWriteOverrun,
"Attempt to write %zd bytes to position %jd in a fixed-size record "
"of %jd bytes",
bytes, static_cast<std::intmax_t>(positionInRecord - header),
static_cast<std::intmax_t>(*openRecl));
return false;
}
}
if (recordLength) {
// It is possible for recordLength to have a value now for a
// variable-length output record if the previous operation
// was a BACKSPACE or non advancing input statement.
recordLength.reset();
beganReadingRecord_ = false;
}
if (IsAfterEndfile()) {
handler.SignalError(IostatWriteAfterEndfile);
return false;
}
CheckDirectAccess(handler);
WriteFrame(frameOffsetInFile_, recordOffsetInFrame_ + furthestAfter, handler);
if (positionInRecord > furthestPositionInRecord) {
std::memset(Frame() + recordOffsetInFrame_ + furthestPositionInRecord, ' ',
positionInRecord - furthestPositionInRecord);
}
char *to{Frame() + recordOffsetInFrame_ + positionInRecord};
std::memcpy(to, data, bytes);
if (swapEndianness_) {
SwapEndianness(to, bytes, elementBytes);
}
positionInRecord += bytes;
furthestPositionInRecord = furthestAfter;
anyWriteSinceLastPositioning_ = true;
return true;
}
bool ExternalFileUnit::Receive(char *data, std::size_t bytes,
std::size_t elementBytes, IoErrorHandler &handler) {
RUNTIME_CHECK(handler, direction_ == Direction::Input);
auto furthestAfter{std::max(furthestPositionInRecord,
positionInRecord + static_cast<std::int64_t>(bytes))};
if (furthestAfter > recordLength.value_or(furthestAfter)) {
handler.SignalError(IostatRecordReadOverrun,
"Attempt to read %zd bytes at position %jd in a record of %jd bytes",
bytes, static_cast<std::intmax_t>(positionInRecord),
static_cast<std::intmax_t>(*recordLength));
return false;
}
auto need{recordOffsetInFrame_ + furthestAfter};
auto got{ReadFrame(frameOffsetInFile_, need, handler)};
if (got >= need) {
std::memcpy(data, Frame() + recordOffsetInFrame_ + positionInRecord, bytes);
if (swapEndianness_) {
SwapEndianness(data, bytes, elementBytes);
}
positionInRecord += bytes;
furthestPositionInRecord = furthestAfter;
return true;
} else {
HitEndOnRead(handler);
return false;
}
}
std::size_t ExternalFileUnit::GetNextInputBytes(
const char *&p, IoErrorHandler &handler) {
RUNTIME_CHECK(handler, direction_ == Direction::Input);
std::size_t length{1};
if (auto recl{EffectiveRecordLength()}) {
if (positionInRecord < *recl) {
length = *recl - positionInRecord;
} else {
p = nullptr;
return 0;
}
}
p = FrameNextInput(handler, length);
return p ? length : 0;
}
const char *ExternalFileUnit::FrameNextInput(
IoErrorHandler &handler, std::size_t bytes) {
RUNTIME_CHECK(handler, isUnformatted.has_value() && !*isUnformatted);
if (static_cast<std::int64_t>(positionInRecord + bytes) <=
recordLength.value_or(positionInRecord + bytes)) {
auto at{recordOffsetInFrame_ + positionInRecord};
auto need{static_cast<std::size_t>(at + bytes)};
auto got{ReadFrame(frameOffsetInFile_, need, handler)};
SetVariableFormattedRecordLength();
if (got >= need) {
return Frame() + at;
}
HitEndOnRead(handler);
}
return nullptr;
}
bool ExternalFileUnit::SetVariableFormattedRecordLength() {
if (recordLength || access == Access::Direct) {
return true;
} else if (FrameLength() > recordOffsetInFrame_) {
const char *record{Frame() + recordOffsetInFrame_};
std::size_t bytes{FrameLength() - recordOffsetInFrame_};
if (const char *nl{FindCharacter(record, '\n', bytes)}) {
recordLength = nl - record;
if (*recordLength > 0 && record[*recordLength - 1] == '\r') {
--*recordLength;
}
return true;
}
}
return false;
}
bool ExternalFileUnit::BeginReadingRecord(IoErrorHandler &handler) {
RUNTIME_CHECK(handler, direction_ == Direction::Input);
if (!beganReadingRecord_) {
beganReadingRecord_ = true;
// Don't use IsAtEOF() to check for an EOF condition here, just detect
// it from a failed or short read from the file. IsAtEOF() could be
// wrong for formatted input if actual newline characters had been
// written in-band by previous WRITEs before a REWIND. In fact,
// now that we know that the unit is being used for input (again),
// it's best to reset endfileRecordNumber and ensure IsAtEOF() will
// now be true on return only if it gets set by HitEndOnRead().
endfileRecordNumber.reset();
if (access == Access::Direct) {
CheckDirectAccess(handler);
auto need{static_cast<std::size_t>(recordOffsetInFrame_ + *openRecl)};
auto got{ReadFrame(frameOffsetInFile_, need, handler)};
if (got >= need) {
recordLength = openRecl;
} else {
recordLength.reset();
HitEndOnRead(handler);
}
} else {
if (anyWriteSinceLastPositioning_ && access == Access::Sequential) {
// Most Fortran implementations allow a READ after a WRITE;
// the read then just hits an EOF.
DoEndfile<false, Direction::Input>(handler);
}
recordLength.reset();
RUNTIME_CHECK(handler, isUnformatted.has_value());
if (*isUnformatted) {
if (access == Access::Sequential) {
BeginSequentialVariableUnformattedInputRecord(handler);
}
} else { // formatted sequential or stream
BeginVariableFormattedInputRecord(handler);
}
}
}
RUNTIME_CHECK(handler,
recordLength.has_value() || !IsRecordFile() || handler.InError());
return !handler.InError();
}
void ExternalFileUnit::FinishReadingRecord(IoErrorHandler &handler) {
RUNTIME_CHECK(handler, direction_ == Direction::Input && beganReadingRecord_);
beganReadingRecord_ = false;
if (handler.GetIoStat() == IostatEnd ||
(IsRecordFile() && !recordLength.has_value())) {
// Avoid bogus crashes in END/ERR circumstances; but
// still increment the current record number so that
// an attempted read of an endfile record, followed by
// a BACKSPACE, will still be at EOF.
++currentRecordNumber;
} else if (IsRecordFile()) {
recordOffsetInFrame_ += *recordLength;
if (access != Access::Direct) {
RUNTIME_CHECK(handler, isUnformatted.has_value());
recordLength.reset();
if (isUnformatted.value_or(false)) {
// Retain footer in frame for more efficient BACKSPACE
frameOffsetInFile_ += recordOffsetInFrame_;
recordOffsetInFrame_ = sizeof(std::uint32_t);
} else { // formatted
if (FrameLength() > recordOffsetInFrame_ &&
Frame()[recordOffsetInFrame_] == '\r') {
++recordOffsetInFrame_;
}
if (FrameLength() > recordOffsetInFrame_ &&
Frame()[recordOffsetInFrame_] == '\n') {
++recordOffsetInFrame_;
}
if (!pinnedFrame || mayPosition()) {
frameOffsetInFile_ += recordOffsetInFrame_;
recordOffsetInFrame_ = 0;
}
}
}
++currentRecordNumber;
} else { // unformatted stream
furthestPositionInRecord =
std::max(furthestPositionInRecord, positionInRecord);
frameOffsetInFile_ += recordOffsetInFrame_ + furthestPositionInRecord;
}
BeginRecord();
}
bool ExternalFileUnit::AdvanceRecord(IoErrorHandler &handler) {
if (direction_ == Direction::Input) {
FinishReadingRecord(handler);
return BeginReadingRecord(handler);
} else { // Direction::Output
bool ok{true};
RUNTIME_CHECK(handler, isUnformatted.has_value());
positionInRecord = furthestPositionInRecord;
if (access == Access::Direct) {
if (furthestPositionInRecord <
openRecl.value_or(furthestPositionInRecord)) {
// Pad remainder of fixed length record
WriteFrame(
frameOffsetInFile_, recordOffsetInFrame_ + *openRecl, handler);
std::memset(Frame() + recordOffsetInFrame_ + furthestPositionInRecord,
isUnformatted.value_or(false) ? 0 : ' ',
*openRecl - furthestPositionInRecord);
furthestPositionInRecord = *openRecl;
}
} else if (*isUnformatted) {
if (access == Access::Sequential) {
// Append the length of a sequential unformatted variable-length record
// as its footer, then overwrite the reserved first four bytes of the
// record with its length as its header. These four bytes were skipped
// over in BeginUnformattedIO<Output>().
// TODO: Break very large records up into subrecords with negative
// headers &/or footers
std::uint32_t length;
length = furthestPositionInRecord - sizeof length;
ok = ok &&
Emit(reinterpret_cast<const char *>(&length), sizeof length,
sizeof length, handler);
positionInRecord = 0;
ok = ok &&
Emit(reinterpret_cast<const char *>(&length), sizeof length,
sizeof length, handler);
} else {
// Unformatted stream: nothing to do
}
} else if (handler.GetIoStat() != IostatOk &&
furthestPositionInRecord == 0) {
// Error in formatted variable length record, and no output yet; do
// nothing, like most other Fortran compilers do.
return true;
} else {
// Terminate formatted variable length record
const char *lineEnding{"\n"};
std::size_t lineEndingBytes{1};
#ifdef _WIN32
if (!isWindowsTextFile()) {
lineEnding = "\r\n";
lineEndingBytes = 2;
}
#endif
ok = ok && Emit(lineEnding, lineEndingBytes, 1, handler);
}
leftTabLimit.reset();
if (IsAfterEndfile()) {
return false;
}
CommitWrites();
++currentRecordNumber;
if (access != Access::Direct) {
impliedEndfile_ = IsRecordFile();
if (IsAtEOF()) {
endfileRecordNumber.reset();
}
}
return ok;
}
}
void ExternalFileUnit::BackspaceRecord(IoErrorHandler &handler) {
if (access == Access::Direct || !IsRecordFile()) {
handler.SignalError(IostatBackspaceNonSequential,
"BACKSPACE(UNIT=%d) on direct-access file or unformatted stream",
unitNumber());
} else {
if (IsAfterEndfile()) {
// BACKSPACE after explicit ENDFILE
currentRecordNumber = *endfileRecordNumber;
} else if (leftTabLimit && direction_ == Direction::Input) {
// BACKSPACE after non-advancing input
leftTabLimit.reset();
} else {
DoImpliedEndfile(handler);
if (frameOffsetInFile_ + recordOffsetInFrame_ > 0) {
--currentRecordNumber;
if (openRecl && access == Access::Direct) {
BackspaceFixedRecord(handler);
} else {
RUNTIME_CHECK(handler, isUnformatted.has_value());
if (isUnformatted.value_or(false)) {
BackspaceVariableUnformattedRecord(handler);
} else {
BackspaceVariableFormattedRecord(handler);
}
}
}
}
BeginRecord();
anyWriteSinceLastPositioning_ = false;
}
}
void ExternalFileUnit::FlushOutput(IoErrorHandler &handler) {
if (!mayPosition()) {
auto frameAt{FrameAt()};
if (frameOffsetInFile_ >= frameAt &&
frameOffsetInFile_ <
static_cast<std::int64_t>(frameAt + FrameLength())) {
// A Flush() that's about to happen to a non-positionable file
// needs to advance frameOffsetInFile_ to prevent attempts at
// impossible seeks
CommitWrites();
leftTabLimit.reset();
}
}
Flush(handler);
}
void ExternalFileUnit::FlushIfTerminal(IoErrorHandler &handler) {
if (isTerminal()) {
FlushOutput(handler);
}
}
void ExternalFileUnit::Endfile(IoErrorHandler &handler) {
if (access == Access::Direct) {
handler.SignalError(IostatEndfileDirect,
"ENDFILE(UNIT=%d) on direct-access file", unitNumber());
} else if (!mayWrite()) {
handler.SignalError(IostatEndfileUnwritable,
"ENDFILE(UNIT=%d) on read-only file", unitNumber());
} else if (IsAfterEndfile()) {
// ENDFILE after ENDFILE
} else {
DoEndfile(handler);
if (IsRecordFile() && access != Access::Direct) {
// Explicit ENDFILE leaves position *after* the endfile record
RUNTIME_CHECK(handler, endfileRecordNumber.has_value());
currentRecordNumber = *endfileRecordNumber + 1;
}
}
}
void ExternalFileUnit::Rewind(IoErrorHandler &handler) {
if (access == Access::Direct) {
handler.SignalError(IostatRewindNonSequential,
"REWIND(UNIT=%d) on non-sequential file", unitNumber());
} else {
DoImpliedEndfile(handler);
SetPosition(0, handler);
currentRecordNumber = 1;
leftTabLimit.reset();
anyWriteSinceLastPositioning_ = false;
}
}
void ExternalFileUnit::SetPosition(std::int64_t pos, IoErrorHandler &handler) {
frameOffsetInFile_ = pos;
recordOffsetInFrame_ = 0;
if (access == Access::Direct) {
directAccessRecWasSet_ = true;
}
BeginRecord();
}
bool ExternalFileUnit::SetStreamPos(
std::int64_t oneBasedPos, IoErrorHandler &handler) {
if (access != Access::Stream) {
handler.SignalError("POS= may not appear unless ACCESS='STREAM'");
return false;
}
if (oneBasedPos < 1) { // POS=1 is beginning of file (12.6.2.11)
handler.SignalError(
"POS=%zd is invalid", static_cast<std::intmax_t>(oneBasedPos));
return false;
}
// A backwards POS= implies truncation after writing, at least in
// Intel and NAG.
if (static_cast<std::size_t>(oneBasedPos - 1) <
frameOffsetInFile_ + recordOffsetInFrame_) {
DoImpliedEndfile(handler);
}
SetPosition(oneBasedPos - 1, handler);
// We no longer know which record we're in. Set currentRecordNumber to
// a large value from whence we can both advance and backspace.
currentRecordNumber = std::numeric_limits<std::int64_t>::max() / 2;
endfileRecordNumber.reset();
return true;
}
bool ExternalFileUnit::SetDirectRec(
std::int64_t oneBasedRec, IoErrorHandler &handler) {
if (access != Access::Direct) {
handler.SignalError("REC= may not appear unless ACCESS='DIRECT'");
return false;
}
if (!openRecl) {
handler.SignalError("RECL= was not specified");
return false;
}
if (oneBasedRec < 1) {
handler.SignalError(
"REC=%zd is invalid", static_cast<std::intmax_t>(oneBasedRec));
return false;
}
currentRecordNumber = oneBasedRec;
SetPosition((oneBasedRec - 1) * *openRecl, handler);
return true;
}
void ExternalFileUnit::EndIoStatement() {
io_.reset();
u_.emplace<std::monostate>();
lock_.Drop();
}
void ExternalFileUnit::BeginSequentialVariableUnformattedInputRecord(
IoErrorHandler &handler) {
RUNTIME_CHECK(handler, access == Access::Sequential);
std::int32_t header{0}, footer{0};
std::size_t need{recordOffsetInFrame_ + sizeof header};
std::size_t got{ReadFrame(frameOffsetInFile_, need, handler)};
// Try to emit informative errors to help debug corrupted files.
const char *error{nullptr};
if (got < need) {
if (got == recordOffsetInFrame_) {
HitEndOnRead(handler);
} else {
error = "Unformatted variable-length sequential file input failed at "
"record #%jd (file offset %jd): truncated record header";
}
} else {
header = ReadHeaderOrFooter(recordOffsetInFrame_);
recordLength = sizeof header + header; // does not include footer
need = recordOffsetInFrame_ + *recordLength + sizeof footer;
got = ReadFrame(frameOffsetInFile_, need, handler);
if (got < need) {
error = "Unformatted variable-length sequential file input failed at "
"record #%jd (file offset %jd): hit EOF reading record with "
"length %jd bytes";
} else {
footer = ReadHeaderOrFooter(recordOffsetInFrame_ + *recordLength);
if (footer != header) {
error = "Unformatted variable-length sequential file input failed at "
"record #%jd (file offset %jd): record header has length %jd "
"that does not match record footer (%jd)";
}
}
}
if (error) {
handler.SignalError(error, static_cast<std::intmax_t>(currentRecordNumber),
static_cast<std::intmax_t>(frameOffsetInFile_),
static_cast<std::intmax_t>(header), static_cast<std::intmax_t>(footer));
// TODO: error recovery
}
positionInRecord = sizeof header;
}
void ExternalFileUnit::BeginVariableFormattedInputRecord(
IoErrorHandler &handler) {
if (this == defaultInput) {
if (defaultOutput) {
defaultOutput->FlushOutput(handler);
}
if (errorOutput) {
errorOutput->FlushOutput(handler);
}
}
std::size_t length{0};
do {
std::size_t need{length + 1};
length =
ReadFrame(frameOffsetInFile_, recordOffsetInFrame_ + need, handler) -
recordOffsetInFrame_;
if (length < need) {
if (length > 0) {
// final record w/o \n
recordLength = length;
unterminatedRecord = true;
} else {
HitEndOnRead(handler);
}
break;
}
} while (!SetVariableFormattedRecordLength());
}
void ExternalFileUnit::BackspaceFixedRecord(IoErrorHandler &handler) {
RUNTIME_CHECK(handler, openRecl.has_value());
if (frameOffsetInFile_ < *openRecl) {
handler.SignalError(IostatBackspaceAtFirstRecord);
} else {
frameOffsetInFile_ -= *openRecl;
}
}
void ExternalFileUnit::BackspaceVariableUnformattedRecord(
IoErrorHandler &handler) {
std::int32_t header{0};
auto headerBytes{static_cast<std::int64_t>(sizeof header)};
frameOffsetInFile_ += recordOffsetInFrame_;
recordOffsetInFrame_ = 0;
if (frameOffsetInFile_ <= headerBytes) {
handler.SignalError(IostatBackspaceAtFirstRecord);
return;
}
// Error conditions here cause crashes, not file format errors, because the
// validity of the file structure before the current record will have been
// checked informatively in NextSequentialVariableUnformattedInputRecord().
std::size_t got{
ReadFrame(frameOffsetInFile_ - headerBytes, headerBytes, handler)};
if (static_cast<std::int64_t>(got) < headerBytes) {
handler.SignalError(IostatShortRead);
return;
}
recordLength = ReadHeaderOrFooter(0);
if (frameOffsetInFile_ < *recordLength + 2 * headerBytes) {
handler.SignalError(IostatBadUnformattedRecord);
return;
}
frameOffsetInFile_ -= *recordLength + 2 * headerBytes;
auto need{static_cast<std::size_t>(
recordOffsetInFrame_ + sizeof header + *recordLength)};
got = ReadFrame(frameOffsetInFile_, need, handler);
if (got < need) {
handler.SignalError(IostatShortRead);
return;
}
header = ReadHeaderOrFooter(recordOffsetInFrame_);
if (header != *recordLength) {
handler.SignalError(IostatBadUnformattedRecord);
return;
}
}
// There's no portable memrchr(), unfortunately, and strrchr() would
// fail on a record with a NUL, so we have to do it the hard way.
static RT_API_ATTRS const char *FindLastNewline(
const char *str, std::size_t length) {
for (const char *p{str + length}; p >= str; p--) {
if (*p == '\n') {
return p;
}
}
return nullptr;
}
void ExternalFileUnit::BackspaceVariableFormattedRecord(
IoErrorHandler &handler) {
// File offset of previous record's newline
auto prevNL{
frameOffsetInFile_ + static_cast<std::int64_t>(recordOffsetInFrame_) - 1};
if (prevNL < 0) {
handler.SignalError(IostatBackspaceAtFirstRecord);
return;
}
while (true) {
if (frameOffsetInFile_ < prevNL) {
if (const char *p{
FindLastNewline(Frame(), prevNL - 1 - frameOffsetInFile_)}) {
recordOffsetInFrame_ = p - Frame() + 1;
recordLength = prevNL - (frameOffsetInFile_ + recordOffsetInFrame_);
break;
}
}
if (frameOffsetInFile_ == 0) {
recordOffsetInFrame_ = 0;
recordLength = prevNL;
break;
}
frameOffsetInFile_ -= std::min<std::int64_t>(frameOffsetInFile_, 1024);
auto need{static_cast<std::size_t>(prevNL + 1 - frameOffsetInFile_)};
auto got{ReadFrame(frameOffsetInFile_, need, handler)};
if (got < need) {
handler.SignalError(IostatShortRead);
return;
}
}
if (Frame()[recordOffsetInFrame_ + *recordLength] != '\n') {
handler.SignalError(IostatMissingTerminator);
return;
}
if (*recordLength > 0 &&
Frame()[recordOffsetInFrame_ + *recordLength - 1] == '\r') {
--*recordLength;
}
}
void ExternalFileUnit::DoImpliedEndfile(IoErrorHandler &handler) {
if (access != Access::Direct) {
if (!impliedEndfile_ && leftTabLimit && direction_ == Direction::Output) {
// Flush a partial record after non-advancing output
impliedEndfile_ = true;
}
if (impliedEndfile_ && mayPosition()) {
DoEndfile(handler);
}
}
impliedEndfile_ = false;
}
template <bool ANY_DIR, Direction DIR>
void ExternalFileUnit::DoEndfile(IoErrorHandler &handler) {
if (IsRecordFile() && access != Access::Direct) {
furthestPositionInRecord =
std::max(positionInRecord, furthestPositionInRecord);
if (leftTabLimit) { // last I/O was non-advancing
if (access == Access::Sequential && direction_ == Direction::Output) {
if constexpr (ANY_DIR || DIR == Direction::Output) {
// When DoEndfile() is called from BeginReadingRecord(),
// this call to AdvanceRecord() may appear as a recursion
// though it may never happen. Expose the call only
// under the constexpr direction check.
AdvanceRecord(handler);
} else {
// This check always fails if we are here.
RUNTIME_CHECK(handler, direction_ != Direction::Output);
}
} else { // Access::Stream or input
leftTabLimit.reset();
++currentRecordNumber;
}
}
endfileRecordNumber = currentRecordNumber;
}
frameOffsetInFile_ += recordOffsetInFrame_ + furthestPositionInRecord;
recordOffsetInFrame_ = 0;
FlushOutput(handler);
Truncate(frameOffsetInFile_, handler);
TruncateFrame(frameOffsetInFile_, handler);
BeginRecord();
impliedEndfile_ = false;
anyWriteSinceLastPositioning_ = false;
}
template void ExternalFileUnit::DoEndfile(IoErrorHandler &handler);
template void ExternalFileUnit::DoEndfile<false, Direction::Output>(
IoErrorHandler &handler);
template void ExternalFileUnit::DoEndfile<false, Direction::Input>(
IoErrorHandler &handler);
void ExternalFileUnit::CommitWrites() {
frameOffsetInFile_ +=
recordOffsetInFrame_ + recordLength.value_or(furthestPositionInRecord);
recordOffsetInFrame_ = 0;
BeginRecord();
}
bool ExternalFileUnit::CheckDirectAccess(IoErrorHandler &handler) {
if (access == Access::Direct) {
RUNTIME_CHECK(handler, openRecl);
if (!directAccessRecWasSet_) {
handler.SignalError(
"No REC= was specified for a data transfer with ACCESS='DIRECT'");
return false;
}
}
return true;
}
void ExternalFileUnit::HitEndOnRead(IoErrorHandler &handler) {
handler.SignalEnd();
if (IsRecordFile() && access != Access::Direct) {
endfileRecordNumber = currentRecordNumber;
}
}
ChildIo &ExternalFileUnit::PushChildIo(IoStatementState &parent) {
OwningPtr<ChildIo> current{std::move(child_)};
Terminator &terminator{parent.GetIoErrorHandler()};
OwningPtr<ChildIo> next{New<ChildIo>{terminator}(parent, std::move(current))};
child_.reset(next.release());
return *child_;
}
void ExternalFileUnit::PopChildIo(ChildIo &child) {
if (child_.get() != &child) {
child.parent().GetIoErrorHandler().Crash(
"ChildIo being popped is not top of stack");
}
child_.reset(child.AcquirePrevious().release()); // deletes top child
}
std::int32_t ExternalFileUnit::ReadHeaderOrFooter(std::int64_t frameOffset) {
std::int32_t word;
char *wordPtr{reinterpret_cast<char *>(&word)};
std::memcpy(wordPtr, Frame() + frameOffset, sizeof word);
if (swapEndianness_) {
SwapEndianness(wordPtr, sizeof word, sizeof word);
}
return word;
}
void ChildIo::EndIoStatement() {
io_.reset();
u_.emplace<std::monostate>();
}
Iostat ChildIo::CheckFormattingAndDirection(
bool unformatted, Direction direction) {
bool parentIsInput{!parent_.get_if<IoDirectionState<Direction::Output>>()};
bool parentIsFormatted{parentIsInput
? parent_.get_if<FormattedIoStatementState<Direction::Input>>() !=
nullptr
: parent_.get_if<FormattedIoStatementState<Direction::Output>>() !=
nullptr};
bool parentIsUnformatted{!parentIsFormatted};
if (unformatted != parentIsUnformatted) {
return unformatted ? IostatUnformattedChildOnFormattedParent
: IostatFormattedChildOnUnformattedParent;
} else if (parentIsInput != (direction == Direction::Input)) {
return parentIsInput ? IostatChildOutputToInputParent
: IostatChildInputFromOutputParent;
} else {
return IostatOk;
}
}
RT_OFFLOAD_API_GROUP_END
} // namespace Fortran::runtime::io
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