1 //===-- runtime/io-stmt.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 "io-stmt.h"
10 #include "connection.h"
11 #include "format.h"
12 #include "tools.h"
13 #include "unit.h"
14 #include "utf.h"
15 #include "flang/Runtime/memory.h"
16 #include <algorithm>
17 #include <cstdio>
18 #include <cstring>
19 #include <limits>
20 #include <type_traits>
21 
22 namespace Fortran::runtime::io {
23 
24 bool IoStatementBase::Emit(const char *, std::size_t, std::size_t) {
25   return false;
26 }
27 
28 bool IoStatementBase::Emit(const char *, std::size_t) { return false; }
29 
30 bool IoStatementBase::Emit(const char16_t *, std::size_t) { return false; }
31 
32 bool IoStatementBase::Emit(const char32_t *, std::size_t) { return false; }
33 
34 std::size_t IoStatementBase::GetNextInputBytes(const char *&p) {
35   p = nullptr;
36   return 0;
37 }
38 
39 bool IoStatementBase::AdvanceRecord(int) { return false; }
40 
41 void IoStatementBase::BackspaceRecord() {}
42 
43 bool IoStatementBase::Receive(char *, std::size_t, std::size_t) {
44   return false;
45 }
46 
47 std::optional<DataEdit> IoStatementBase::GetNextDataEdit(
48     IoStatementState &, int) {
49   return std::nullopt;
50 }
51 
52 ExternalFileUnit *IoStatementBase::GetExternalFileUnit() const {
53   return nullptr;
54 }
55 
56 bool IoStatementBase::BeginReadingRecord() { return true; }
57 
58 void IoStatementBase::FinishReadingRecord() {}
59 
60 void IoStatementBase::HandleAbsolutePosition(std::int64_t) {}
61 
62 void IoStatementBase::HandleRelativePosition(std::int64_t) {}
63 
64 bool IoStatementBase::Inquire(InquiryKeywordHash, char *, std::size_t) {
65   return false;
66 }
67 
68 bool IoStatementBase::Inquire(InquiryKeywordHash, bool &) { return false; }
69 
70 bool IoStatementBase::Inquire(InquiryKeywordHash, std::int64_t, bool &) {
71   return false;
72 }
73 
74 bool IoStatementBase::Inquire(InquiryKeywordHash, std::int64_t &) {
75   return false;
76 }
77 
78 void IoStatementBase::BadInquiryKeywordHashCrash(InquiryKeywordHash inquiry) {
79   char buffer[16];
80   const char *decode{InquiryKeywordHashDecode(buffer, sizeof buffer, inquiry)};
81   Crash("Bad InquiryKeywordHash 0x%x (%s)", inquiry,
82       decode ? decode : "(cannot decode)");
83 }
84 
85 template <Direction DIR, typename CHAR>
86 InternalIoStatementState<DIR, CHAR>::InternalIoStatementState(
87     Buffer scalar, std::size_t length, const char *sourceFile, int sourceLine)
88     : IoStatementBase{sourceFile, sourceLine}, unit_{scalar, length} {}
89 
90 template <Direction DIR, typename CHAR>
91 InternalIoStatementState<DIR, CHAR>::InternalIoStatementState(
92     const Descriptor &d, const char *sourceFile, int sourceLine)
93     : IoStatementBase{sourceFile, sourceLine}, unit_{d, *this} {}
94 
95 template <Direction DIR, typename CHAR>
96 bool InternalIoStatementState<DIR, CHAR>::Emit(
97     const CharType *data, std::size_t chars) {
98   if constexpr (DIR == Direction::Input) {
99     Crash("InternalIoStatementState<Direction::Input>::Emit() called");
100     return false;
101   }
102   return unit_.Emit(data, chars * sizeof(CharType), *this);
103 }
104 
105 template <Direction DIR, typename CHAR>
106 std::size_t InternalIoStatementState<DIR, CHAR>::GetNextInputBytes(
107     const char *&p) {
108   return unit_.GetNextInputBytes(p, *this);
109 }
110 
111 template <Direction DIR, typename CHAR>
112 bool InternalIoStatementState<DIR, CHAR>::AdvanceRecord(int n) {
113   while (n-- > 0) {
114     if (!unit_.AdvanceRecord(*this)) {
115       return false;
116     }
117   }
118   return true;
119 }
120 
121 template <Direction DIR, typename CHAR>
122 void InternalIoStatementState<DIR, CHAR>::BackspaceRecord() {
123   unit_.BackspaceRecord(*this);
124 }
125 
126 template <Direction DIR, typename CHAR>
127 int InternalIoStatementState<DIR, CHAR>::EndIoStatement() {
128   if constexpr (DIR == Direction::Output) {
129     unit_.EndIoStatement(); // fill
130   }
131   auto result{IoStatementBase::EndIoStatement()};
132   if (free_) {
133     FreeMemory(this);
134   }
135   return result;
136 }
137 
138 template <Direction DIR, typename CHAR>
139 void InternalIoStatementState<DIR, CHAR>::HandleAbsolutePosition(
140     std::int64_t n) {
141   return unit_.HandleAbsolutePosition(n);
142 }
143 
144 template <Direction DIR, typename CHAR>
145 void InternalIoStatementState<DIR, CHAR>::HandleRelativePosition(
146     std::int64_t n) {
147   return unit_.HandleRelativePosition(n);
148 }
149 
150 template <Direction DIR, typename CHAR>
151 InternalFormattedIoStatementState<DIR, CHAR>::InternalFormattedIoStatementState(
152     Buffer buffer, std::size_t length, const CHAR *format,
153     std::size_t formatLength, const char *sourceFile, int sourceLine)
154     : InternalIoStatementState<DIR, CHAR>{buffer, length, sourceFile,
155           sourceLine},
156       ioStatementState_{*this}, format_{*this, format, formatLength} {}
157 
158 template <Direction DIR, typename CHAR>
159 InternalFormattedIoStatementState<DIR, CHAR>::InternalFormattedIoStatementState(
160     const Descriptor &d, const CHAR *format, std::size_t formatLength,
161     const char *sourceFile, int sourceLine)
162     : InternalIoStatementState<DIR, CHAR>{d, sourceFile, sourceLine},
163       ioStatementState_{*this}, format_{*this, format, formatLength} {}
164 
165 template <Direction DIR, typename CHAR>
166 void InternalFormattedIoStatementState<DIR, CHAR>::CompleteOperation() {
167   if (!this->completedOperation()) {
168     if constexpr (DIR == Direction::Output) {
169       format_.Finish(*this); // ignore any remaining input positioning actions
170     }
171     IoStatementBase::CompleteOperation();
172   }
173 }
174 
175 template <Direction DIR, typename CHAR>
176 int InternalFormattedIoStatementState<DIR, CHAR>::EndIoStatement() {
177   CompleteOperation();
178   return InternalIoStatementState<DIR, CHAR>::EndIoStatement();
179 }
180 
181 template <Direction DIR, typename CHAR>
182 InternalListIoStatementState<DIR, CHAR>::InternalListIoStatementState(
183     Buffer buffer, std::size_t length, const char *sourceFile, int sourceLine)
184     : InternalIoStatementState<DIR, CharType>{buffer, length, sourceFile,
185           sourceLine},
186       ioStatementState_{*this} {}
187 
188 template <Direction DIR, typename CHAR>
189 InternalListIoStatementState<DIR, CHAR>::InternalListIoStatementState(
190     const Descriptor &d, const char *sourceFile, int sourceLine)
191     : InternalIoStatementState<DIR, CharType>{d, sourceFile, sourceLine},
192       ioStatementState_{*this} {}
193 
194 ExternalIoStatementBase::ExternalIoStatementBase(
195     ExternalFileUnit &unit, const char *sourceFile, int sourceLine)
196     : IoStatementBase{sourceFile, sourceLine}, unit_{unit} {}
197 
198 MutableModes &ExternalIoStatementBase::mutableModes() { return unit_.modes; }
199 
200 ConnectionState &ExternalIoStatementBase::GetConnectionState() { return unit_; }
201 
202 int ExternalIoStatementBase::EndIoStatement() {
203   CompleteOperation();
204   auto result{IoStatementBase::EndIoStatement()};
205   unit_.EndIoStatement(); // annihilates *this in unit_.u_
206   return result;
207 }
208 
209 void OpenStatementState::set_path(const char *path, std::size_t length) {
210   pathLength_ = TrimTrailingSpaces(path, length);
211   path_ = SaveDefaultCharacter(path, pathLength_, *this);
212 }
213 
214 void OpenStatementState::CompleteOperation() {
215   if (completedOperation()) {
216     return;
217   }
218   if (position_) {
219     if (access_ && *access_ == Access::Direct) {
220       SignalError("POSITION= may not be set with ACCESS='DIRECT'");
221       position_.reset();
222     }
223   }
224   if (status_) { // 12.5.6.10
225     if ((*status_ == OpenStatus::New || *status_ == OpenStatus::Replace) &&
226         !path_.get()) {
227       SignalError("FILE= required on OPEN with STATUS='NEW' or 'REPLACE'");
228     } else if (*status_ == OpenStatus::Scratch && path_.get()) {
229       SignalError("FILE= may not appear on OPEN with STATUS='SCRATCH'");
230     }
231   }
232   if (path_.get() || wasExtant_ ||
233       (status_ && *status_ == OpenStatus::Scratch)) {
234     unit().OpenUnit(status_, action_, position_.value_or(Position::AsIs),
235         std::move(path_), pathLength_, convert_, *this);
236   } else {
237     unit().OpenAnonymousUnit(
238         status_, action_, position_.value_or(Position::AsIs), convert_, *this);
239   }
240   if (access_) {
241     if (*access_ != unit().access) {
242       if (wasExtant_) {
243         SignalError("ACCESS= may not be changed on an open unit");
244         access_.reset();
245       }
246     }
247     if (access_) {
248       unit().access = *access_;
249     }
250   }
251   if (!unit().isUnformatted) {
252     unit().isUnformatted = isUnformatted_;
253   }
254   if (isUnformatted_ && *isUnformatted_ != *unit().isUnformatted) {
255     if (wasExtant_) {
256       SignalError("FORM= may not be changed on an open unit");
257     }
258     unit().isUnformatted = *isUnformatted_;
259   }
260   if (!unit().isUnformatted) {
261     // Set default format (C.7.4 point 2).
262     unit().isUnformatted = unit().access != Access::Sequential;
263   }
264   if (!wasExtant_ && InError()) {
265     // Release the new unit on failure
266     unit().CloseUnit(CloseStatus::Delete, *this);
267     unit().DestroyClosed();
268   }
269   IoStatementBase::CompleteOperation();
270 }
271 
272 int OpenStatementState::EndIoStatement() {
273   CompleteOperation();
274   return ExternalIoStatementBase::EndIoStatement();
275 }
276 
277 int CloseStatementState::EndIoStatement() {
278   CompleteOperation();
279   int result{ExternalIoStatementBase::EndIoStatement()};
280   unit().CloseUnit(status_, *this);
281   unit().DestroyClosed();
282   return result;
283 }
284 
285 void NoUnitIoStatementState::CompleteOperation() {
286   IoStatementBase::CompleteOperation();
287 }
288 
289 int NoUnitIoStatementState::EndIoStatement() {
290   CompleteOperation();
291   auto result{IoStatementBase::EndIoStatement()};
292   FreeMemory(this);
293   return result;
294 }
295 
296 template <Direction DIR>
297 ExternalIoStatementState<DIR>::ExternalIoStatementState(
298     ExternalFileUnit &unit, const char *sourceFile, int sourceLine)
299     : ExternalIoStatementBase{unit, sourceFile, sourceLine}, mutableModes_{
300                                                                  unit.modes} {
301   if constexpr (DIR == Direction::Output) {
302     // If the last statement was a non-advancing IO input statement, the unit
303     // furthestPositionInRecord was not advanced, but the positionInRecord may
304     // have been advanced. Advance furthestPositionInRecord here to avoid
305     // overwriting the part of the record that has been read with blanks.
306     unit.furthestPositionInRecord =
307         std::max(unit.furthestPositionInRecord, unit.positionInRecord);
308   }
309 }
310 
311 template <Direction DIR>
312 void ExternalIoStatementState<DIR>::CompleteOperation() {
313   if (completedOperation()) {
314     return;
315   }
316   if constexpr (DIR == Direction::Input) {
317     BeginReadingRecord(); // in case there were no I/O items
318     if (!mutableModes().nonAdvancing || GetIoStat() == IostatEor) {
319       FinishReadingRecord();
320     }
321   } else { // output
322     if (mutableModes().nonAdvancing) {
323       // Make effects of positioning past the last Emit() visible with blanks.
324       std::int64_t n{unit().positionInRecord - unit().furthestPositionInRecord};
325       unit().positionInRecord = unit().furthestPositionInRecord;
326       while (n-- > 0 && unit().Emit(" ", 1, 1, *this)) {
327       }
328       unit().leftTabLimit = unit().furthestPositionInRecord;
329     } else {
330       unit().leftTabLimit.reset();
331       unit().AdvanceRecord(*this);
332     }
333     unit().FlushIfTerminal(*this);
334   }
335   return IoStatementBase::CompleteOperation();
336 }
337 
338 template <Direction DIR> int ExternalIoStatementState<DIR>::EndIoStatement() {
339   CompleteOperation();
340   return ExternalIoStatementBase::EndIoStatement();
341 }
342 
343 template <Direction DIR>
344 bool ExternalIoStatementState<DIR>::Emit(
345     const char *data, std::size_t bytes, std::size_t elementBytes) {
346   if constexpr (DIR == Direction::Input) {
347     Crash("ExternalIoStatementState::Emit(char) called for input statement");
348   }
349   return unit().Emit(data, bytes, elementBytes, *this);
350 }
351 
352 template <Direction DIR>
353 bool ExternalIoStatementState<DIR>::Emit(const char *data, std::size_t bytes) {
354   if constexpr (DIR == Direction::Input) {
355     Crash("ExternalIoStatementState::Emit(char) called for input statement");
356   }
357   return unit().Emit(data, bytes, 0, *this);
358 }
359 
360 template <Direction DIR>
361 bool ExternalIoStatementState<DIR>::Emit(
362     const char16_t *data, std::size_t chars) {
363   if constexpr (DIR == Direction::Input) {
364     Crash(
365         "ExternalIoStatementState::Emit(char16_t) called for input statement");
366   }
367   return unit().Emit(reinterpret_cast<const char *>(data), chars * sizeof *data,
368       sizeof *data, *this);
369 }
370 
371 template <Direction DIR>
372 bool ExternalIoStatementState<DIR>::Emit(
373     const char32_t *data, std::size_t chars) {
374   if constexpr (DIR == Direction::Input) {
375     Crash(
376         "ExternalIoStatementState::Emit(char32_t) called for input statement");
377   }
378   return unit().Emit(reinterpret_cast<const char *>(data), chars * sizeof *data,
379       sizeof *data, *this);
380 }
381 
382 template <Direction DIR>
383 std::size_t ExternalIoStatementState<DIR>::GetNextInputBytes(const char *&p) {
384   return unit().GetNextInputBytes(p, *this);
385 }
386 
387 template <Direction DIR>
388 bool ExternalIoStatementState<DIR>::AdvanceRecord(int n) {
389   while (n-- > 0) {
390     if (!unit().AdvanceRecord(*this)) {
391       return false;
392     }
393   }
394   return true;
395 }
396 
397 template <Direction DIR> void ExternalIoStatementState<DIR>::BackspaceRecord() {
398   unit().BackspaceRecord(*this);
399 }
400 
401 template <Direction DIR>
402 void ExternalIoStatementState<DIR>::HandleAbsolutePosition(std::int64_t n) {
403   return unit().HandleAbsolutePosition(n);
404 }
405 
406 template <Direction DIR>
407 void ExternalIoStatementState<DIR>::HandleRelativePosition(std::int64_t n) {
408   return unit().HandleRelativePosition(n);
409 }
410 
411 template <Direction DIR>
412 bool ExternalIoStatementState<DIR>::BeginReadingRecord() {
413   if constexpr (DIR == Direction::Input) {
414     return unit().BeginReadingRecord(*this);
415   } else {
416     Crash("ExternalIoStatementState<Direction::Output>::BeginReadingRecord() "
417           "called");
418     return false;
419   }
420 }
421 
422 template <Direction DIR>
423 void ExternalIoStatementState<DIR>::FinishReadingRecord() {
424   if constexpr (DIR == Direction::Input) {
425     unit().FinishReadingRecord(*this);
426   } else {
427     Crash("ExternalIoStatementState<Direction::Output>::FinishReadingRecord() "
428           "called");
429   }
430 }
431 
432 template <Direction DIR, typename CHAR>
433 ExternalFormattedIoStatementState<DIR, CHAR>::ExternalFormattedIoStatementState(
434     ExternalFileUnit &unit, const CHAR *format, std::size_t formatLength,
435     const char *sourceFile, int sourceLine)
436     : ExternalIoStatementState<DIR>{unit, sourceFile, sourceLine},
437       format_{*this, format, formatLength} {}
438 
439 template <Direction DIR, typename CHAR>
440 void ExternalFormattedIoStatementState<DIR, CHAR>::CompleteOperation() {
441   if (this->completedOperation()) {
442     return;
443   }
444   if constexpr (DIR == Direction::Input) {
445     this->BeginReadingRecord(); // in case there were no I/O items
446   }
447   format_.Finish(*this);
448   return ExternalIoStatementState<DIR>::CompleteOperation();
449 }
450 
451 template <Direction DIR, typename CHAR>
452 int ExternalFormattedIoStatementState<DIR, CHAR>::EndIoStatement() {
453   CompleteOperation();
454   return ExternalIoStatementState<DIR>::EndIoStatement();
455 }
456 
457 std::optional<DataEdit> IoStatementState::GetNextDataEdit(int n) {
458   return std::visit(
459       [&](auto &x) { return x.get().GetNextDataEdit(*this, n); }, u_);
460 }
461 
462 bool IoStatementState::Emit(
463     const char *data, std::size_t n, std::size_t elementBytes) {
464   return std::visit(
465       [=](auto &x) { return x.get().Emit(data, n, elementBytes); }, u_);
466 }
467 
468 bool IoStatementState::Emit(const char *data, std::size_t n) {
469   return std::visit([=](auto &x) { return x.get().Emit(data, n); }, u_);
470 }
471 
472 bool IoStatementState::Emit(const char16_t *data, std::size_t chars) {
473   return std::visit([=](auto &x) { return x.get().Emit(data, chars); }, u_);
474 }
475 
476 bool IoStatementState::Emit(const char32_t *data, std::size_t chars) {
477   return std::visit([=](auto &x) { return x.get().Emit(data, chars); }, u_);
478 }
479 
480 template <typename CHAR>
481 bool IoStatementState::EmitEncoded(const CHAR *data0, std::size_t chars) {
482   // Don't allow sign extension
483   using UnsignedChar = std::make_unsigned_t<CHAR>;
484   const UnsignedChar *data{reinterpret_cast<const UnsignedChar *>(data0)};
485   if (GetConnectionState().useUTF8<CHAR>()) {
486     char buffer[256];
487     std::size_t at{0};
488     while (chars-- > 0) {
489       auto len{EncodeUTF8(buffer + at, *data++)};
490       at += len;
491       if (at + maxUTF8Bytes > sizeof buffer) {
492         if (!Emit(buffer, at)) {
493           return false;
494         }
495         at = 0;
496       }
497     }
498     return at == 0 || Emit(buffer, at);
499   } else {
500     return Emit(data0, chars);
501   }
502 }
503 
504 bool IoStatementState::Receive(
505     char *data, std::size_t n, std::size_t elementBytes) {
506   return std::visit(
507       [=](auto &x) { return x.get().Receive(data, n, elementBytes); }, u_);
508 }
509 
510 std::size_t IoStatementState::GetNextInputBytes(const char *&p) {
511   return std::visit([&](auto &x) { return x.get().GetNextInputBytes(p); }, u_);
512 }
513 
514 bool IoStatementState::AdvanceRecord(int n) {
515   return std::visit([=](auto &x) { return x.get().AdvanceRecord(n); }, u_);
516 }
517 
518 void IoStatementState::BackspaceRecord() {
519   std::visit([](auto &x) { x.get().BackspaceRecord(); }, u_);
520 }
521 
522 void IoStatementState::HandleRelativePosition(std::int64_t n) {
523   std::visit([=](auto &x) { x.get().HandleRelativePosition(n); }, u_);
524 }
525 
526 void IoStatementState::HandleAbsolutePosition(std::int64_t n) {
527   std::visit([=](auto &x) { x.get().HandleAbsolutePosition(n); }, u_);
528 }
529 
530 void IoStatementState::CompleteOperation() {
531   std::visit([](auto &x) { x.get().CompleteOperation(); }, u_);
532 }
533 
534 int IoStatementState::EndIoStatement() {
535   return std::visit([](auto &x) { return x.get().EndIoStatement(); }, u_);
536 }
537 
538 ConnectionState &IoStatementState::GetConnectionState() {
539   return std::visit(
540       [](auto &x) -> ConnectionState & { return x.get().GetConnectionState(); },
541       u_);
542 }
543 
544 MutableModes &IoStatementState::mutableModes() {
545   return std::visit(
546       [](auto &x) -> MutableModes & { return x.get().mutableModes(); }, u_);
547 }
548 
549 bool IoStatementState::BeginReadingRecord() {
550   return std::visit([](auto &x) { return x.get().BeginReadingRecord(); }, u_);
551 }
552 
553 IoErrorHandler &IoStatementState::GetIoErrorHandler() const {
554   return std::visit(
555       [](auto &x) -> IoErrorHandler & {
556         return static_cast<IoErrorHandler &>(x.get());
557       },
558       u_);
559 }
560 
561 ExternalFileUnit *IoStatementState::GetExternalFileUnit() const {
562   return std::visit([](auto &x) { return x.get().GetExternalFileUnit(); }, u_);
563 }
564 
565 std::optional<char32_t> IoStatementState::GetCurrentChar(
566     std::size_t &byteCount) {
567   const char *p{nullptr};
568   std::size_t bytes{GetNextInputBytes(p)};
569   if (bytes == 0) {
570     byteCount = 0;
571     return std::nullopt;
572   } else {
573     if (GetConnectionState().isUTF8) {
574       std::size_t length{MeasureUTF8Bytes(*p)};
575       if (length <= bytes) {
576         if (auto result{DecodeUTF8(p)}) {
577           byteCount = length;
578           return result;
579         }
580       }
581       GetIoErrorHandler().SignalError(IostatUTF8Decoding);
582       // Error recovery: return the next byte
583     }
584     byteCount = 1;
585     return *p;
586   }
587 }
588 
589 bool IoStatementState::EmitRepeated(char ch, std::size_t n) {
590   return std::visit(
591       [=](auto &x) {
592         for (std::size_t j{0}; j < n; ++j) {
593           if (!x.get().Emit(&ch, 1)) {
594             return false;
595           }
596         }
597         return true;
598       },
599       u_);
600 }
601 
602 bool IoStatementState::EmitField(
603     const char *p, std::size_t length, std::size_t width) {
604   if (width <= 0) {
605     width = static_cast<int>(length);
606   }
607   if (length > static_cast<std::size_t>(width)) {
608     return EmitRepeated('*', width);
609   } else {
610     return EmitRepeated(' ', static_cast<int>(width - length)) &&
611         Emit(p, length);
612   }
613 }
614 
615 std::optional<char32_t> IoStatementState::NextInField(
616     std::optional<int> &remaining, const DataEdit &edit) {
617   std::size_t byteCount{0};
618   if (!remaining) { // Stream, list-directed, or NAMELIST
619     if (auto next{GetCurrentChar(byteCount)}) {
620       if (edit.IsListDirected()) {
621         // list-directed or NAMELIST: check for separators
622         switch (*next) {
623         case ' ':
624         case '\t':
625         case ';':
626         case '/':
627         case '(':
628         case ')':
629         case '\'':
630         case '"':
631         case '*':
632         case '\n': // for stream access
633           return std::nullopt;
634         case ',':
635           if (edit.modes.editingFlags & decimalComma) {
636             break;
637           } else {
638             return std::nullopt;
639           }
640         default:
641           break;
642         }
643       }
644       HandleRelativePosition(byteCount);
645       GotChar(byteCount);
646       return next;
647     }
648   } else if (*remaining > 0) {
649     if (auto next{GetCurrentChar(byteCount)}) {
650       if (byteCount > static_cast<std::size_t>(*remaining)) {
651         return std::nullopt;
652       }
653       *remaining -= byteCount;
654       HandleRelativePosition(byteCount);
655       GotChar(byteCount);
656       return next;
657     }
658     if (CheckForEndOfRecord()) { // do padding
659       --*remaining;
660       return std::optional<char32_t>{' '};
661     }
662   }
663   return std::nullopt;
664 }
665 
666 bool IoStatementState::CheckForEndOfRecord() {
667   const ConnectionState &connection{GetConnectionState()};
668   if (!connection.IsAtEOF()) {
669     if (auto length{connection.EffectiveRecordLength()}) {
670       if (connection.positionInRecord >= *length) {
671         IoErrorHandler &handler{GetIoErrorHandler()};
672         if (mutableModes().nonAdvancing) {
673           handler.SignalEor();
674         } else if (connection.openRecl && !connection.modes.pad) {
675           handler.SignalError(IostatRecordReadOverrun);
676         }
677         return connection.modes.pad; // PAD='YES'
678       }
679     }
680   }
681   return false;
682 }
683 
684 bool IoStatementState::Inquire(
685     InquiryKeywordHash inquiry, char *out, std::size_t chars) {
686   return std::visit(
687       [&](auto &x) { return x.get().Inquire(inquiry, out, chars); }, u_);
688 }
689 
690 bool IoStatementState::Inquire(InquiryKeywordHash inquiry, bool &out) {
691   return std::visit([&](auto &x) { return x.get().Inquire(inquiry, out); }, u_);
692 }
693 
694 bool IoStatementState::Inquire(
695     InquiryKeywordHash inquiry, std::int64_t id, bool &out) {
696   return std::visit(
697       [&](auto &x) { return x.get().Inquire(inquiry, id, out); }, u_);
698 }
699 
700 bool IoStatementState::Inquire(InquiryKeywordHash inquiry, std::int64_t &n) {
701   return std::visit([&](auto &x) { return x.get().Inquire(inquiry, n); }, u_);
702 }
703 
704 void IoStatementState::GotChar(int n) {
705   if (auto *formattedIn{
706           get_if<FormattedIoStatementState<Direction::Input>>()}) {
707     formattedIn->GotChar(n);
708   } else {
709     GetIoErrorHandler().Crash("IoStatementState::GotChar() called for "
710                               "statement that is not formatted input");
711   }
712 }
713 
714 std::size_t
715 FormattedIoStatementState<Direction::Input>::GetEditDescriptorChars() const {
716   return chars_;
717 }
718 
719 void FormattedIoStatementState<Direction::Input>::GotChar(int n) {
720   chars_ += n;
721 }
722 
723 bool ListDirectedStatementState<Direction::Output>::EmitLeadingSpaceOrAdvance(
724     IoStatementState &io, std::size_t length, bool isCharacter) {
725   if (length == 0) {
726     return true;
727   }
728   const ConnectionState &connection{io.GetConnectionState()};
729   int space{connection.positionInRecord == 0 ||
730       !(isCharacter && lastWasUndelimitedCharacter())};
731   set_lastWasUndelimitedCharacter(false);
732   if (connection.NeedAdvance(space + length)) {
733     return io.AdvanceRecord();
734   }
735   if (space) {
736     return io.Emit(" ", 1);
737   }
738   return true;
739 }
740 
741 std::optional<DataEdit>
742 ListDirectedStatementState<Direction::Output>::GetNextDataEdit(
743     IoStatementState &io, int maxRepeat) {
744   DataEdit edit;
745   edit.descriptor = DataEdit::ListDirected;
746   edit.repeat = maxRepeat;
747   edit.modes = io.mutableModes();
748   return edit;
749 }
750 
751 std::optional<DataEdit>
752 ListDirectedStatementState<Direction::Input>::GetNextDataEdit(
753     IoStatementState &io, int maxRepeat) {
754   // N.B. list-directed transfers cannot be nonadvancing (C1221)
755   ConnectionState &connection{io.GetConnectionState()};
756   DataEdit edit;
757   edit.descriptor = DataEdit::ListDirected;
758   edit.repeat = 1; // may be overridden below
759   edit.modes = io.mutableModes();
760   if (hitSlash_) { // everything after '/' is nullified
761     edit.descriptor = DataEdit::ListDirectedNullValue;
762     return edit;
763   }
764   char32_t comma{','};
765   if (edit.modes.editingFlags & decimalComma) {
766     comma = ';';
767   }
768   std::size_t byteCount{0};
769   if (remaining_ > 0 && !realPart_) { // "r*c" repetition in progress
770     RUNTIME_CHECK(io.GetIoErrorHandler(), repeatPosition_.has_value());
771     repeatPosition_.reset(); // restores the saved position
772     if (!imaginaryPart_) {
773       edit.repeat = std::min<int>(remaining_, maxRepeat);
774       auto ch{io.GetCurrentChar(byteCount)};
775       if (!ch || *ch == ' ' || *ch == '\t' || *ch == comma) {
776         // "r*" repeated null
777         edit.descriptor = DataEdit::ListDirectedNullValue;
778       }
779     }
780     remaining_ -= edit.repeat;
781     if (remaining_ > 0) {
782       repeatPosition_.emplace(io);
783     }
784     return edit;
785   }
786   // Skip separators, handle a "r*c" repeat count; see 13.10.2 in Fortran 2018
787   if (imaginaryPart_) {
788     imaginaryPart_ = false;
789   } else if (realPart_) {
790     realPart_ = false;
791     imaginaryPart_ = true;
792     edit.descriptor = DataEdit::ListDirectedImaginaryPart;
793   }
794   auto ch{io.GetNextNonBlank(byteCount)};
795   if (ch && *ch == comma && eatComma_) {
796     // Consume comma & whitespace after previous item.
797     // This includes the comma between real and imaginary components
798     // in list-directed/NAMELIST complex input.
799     // (When DECIMAL='COMMA', the comma is actually a semicolon.)
800     io.HandleRelativePosition(byteCount);
801     ch = io.GetNextNonBlank(byteCount);
802   }
803   eatComma_ = true;
804   if (!ch) {
805     return std::nullopt;
806   }
807   if (*ch == '/') {
808     hitSlash_ = true;
809     edit.descriptor = DataEdit::ListDirectedNullValue;
810     return edit;
811   }
812   if (*ch == comma) { // separator: null value
813     edit.descriptor = DataEdit::ListDirectedNullValue;
814     return edit;
815   }
816   if (imaginaryPart_) { // can't repeat components
817     return edit;
818   }
819   if (*ch >= '0' && *ch <= '9') { // look for "r*" repetition count
820     auto start{connection.positionInRecord};
821     int r{0};
822     do {
823       static auto constexpr clamp{(std::numeric_limits<int>::max() - '9') / 10};
824       if (r >= clamp) {
825         r = 0;
826         break;
827       }
828       r = 10 * r + (*ch - '0');
829       io.HandleRelativePosition(byteCount);
830       ch = io.GetCurrentChar(byteCount);
831     } while (ch && *ch >= '0' && *ch <= '9');
832     if (r > 0 && ch && *ch == '*') { // subtle: r must be nonzero
833       io.HandleRelativePosition(byteCount);
834       ch = io.GetCurrentChar(byteCount);
835       if (ch && *ch == '/') { // r*/
836         hitSlash_ = true;
837         edit.descriptor = DataEdit::ListDirectedNullValue;
838         return edit;
839       }
840       if (!ch || *ch == ' ' || *ch == '\t' || *ch == comma) { // "r*" null
841         edit.descriptor = DataEdit::ListDirectedNullValue;
842       }
843       edit.repeat = std::min<int>(r, maxRepeat);
844       remaining_ = r - edit.repeat;
845       if (remaining_ > 0) {
846         repeatPosition_.emplace(io);
847       }
848     } else { // not a repetition count, just an integer value; rewind
849       connection.positionInRecord = start;
850     }
851   }
852   if (!imaginaryPart_ && ch && *ch == '(') {
853     realPart_ = true;
854     io.HandleRelativePosition(byteCount);
855     edit.descriptor = DataEdit::ListDirectedRealPart;
856   }
857   return edit;
858 }
859 
860 template <Direction DIR>
861 bool ExternalUnformattedIoStatementState<DIR>::Receive(
862     char *data, std::size_t bytes, std::size_t elementBytes) {
863   if constexpr (DIR == Direction::Output) {
864     this->Crash("ExternalUnformattedIoStatementState::Receive() called for "
865                 "output statement");
866   }
867   return this->unit().Receive(data, bytes, elementBytes, *this);
868 }
869 
870 template <Direction DIR>
871 ChildIoStatementState<DIR>::ChildIoStatementState(
872     ChildIo &child, const char *sourceFile, int sourceLine)
873     : IoStatementBase{sourceFile, sourceLine}, child_{child} {}
874 
875 template <Direction DIR>
876 MutableModes &ChildIoStatementState<DIR>::mutableModes() {
877   return child_.parent().mutableModes();
878 }
879 
880 template <Direction DIR>
881 ConnectionState &ChildIoStatementState<DIR>::GetConnectionState() {
882   return child_.parent().GetConnectionState();
883 }
884 
885 template <Direction DIR>
886 ExternalFileUnit *ChildIoStatementState<DIR>::GetExternalFileUnit() const {
887   return child_.parent().GetExternalFileUnit();
888 }
889 
890 template <Direction DIR> void ChildIoStatementState<DIR>::CompleteOperation() {
891   IoStatementBase::CompleteOperation();
892 }
893 
894 template <Direction DIR> int ChildIoStatementState<DIR>::EndIoStatement() {
895   CompleteOperation();
896   auto result{IoStatementBase::EndIoStatement()};
897   child_.EndIoStatement(); // annihilates *this in child_.u_
898   return result;
899 }
900 
901 template <Direction DIR>
902 bool ChildIoStatementState<DIR>::Emit(
903     const char *data, std::size_t bytes, std::size_t elementBytes) {
904   return child_.parent().Emit(data, bytes, elementBytes);
905 }
906 
907 template <Direction DIR>
908 bool ChildIoStatementState<DIR>::Emit(const char *data, std::size_t bytes) {
909   return child_.parent().Emit(data, bytes);
910 }
911 
912 template <Direction DIR>
913 bool ChildIoStatementState<DIR>::Emit(const char16_t *data, std::size_t chars) {
914   return child_.parent().Emit(data, chars);
915 }
916 
917 template <Direction DIR>
918 bool ChildIoStatementState<DIR>::Emit(const char32_t *data, std::size_t chars) {
919   return child_.parent().Emit(data, chars);
920 }
921 
922 template <Direction DIR>
923 std::size_t ChildIoStatementState<DIR>::GetNextInputBytes(const char *&p) {
924   return child_.parent().GetNextInputBytes(p);
925 }
926 
927 template <Direction DIR>
928 void ChildIoStatementState<DIR>::HandleAbsolutePosition(std::int64_t n) {
929   return child_.parent().HandleAbsolutePosition(n);
930 }
931 
932 template <Direction DIR>
933 void ChildIoStatementState<DIR>::HandleRelativePosition(std::int64_t n) {
934   return child_.parent().HandleRelativePosition(n);
935 }
936 
937 template <Direction DIR, typename CHAR>
938 ChildFormattedIoStatementState<DIR, CHAR>::ChildFormattedIoStatementState(
939     ChildIo &child, const CHAR *format, std::size_t formatLength,
940     const char *sourceFile, int sourceLine)
941     : ChildIoStatementState<DIR>{child, sourceFile, sourceLine},
942       mutableModes_{child.parent().mutableModes()}, format_{*this, format,
943                                                         formatLength} {}
944 
945 template <Direction DIR, typename CHAR>
946 void ChildFormattedIoStatementState<DIR, CHAR>::CompleteOperation() {
947   if (!this->completedOperation()) {
948     format_.Finish(*this);
949     ChildIoStatementState<DIR>::CompleteOperation();
950   }
951 }
952 
953 template <Direction DIR, typename CHAR>
954 int ChildFormattedIoStatementState<DIR, CHAR>::EndIoStatement() {
955   CompleteOperation();
956   return ChildIoStatementState<DIR>::EndIoStatement();
957 }
958 
959 template <Direction DIR, typename CHAR>
960 bool ChildFormattedIoStatementState<DIR, CHAR>::AdvanceRecord(int) {
961   return false; // no can do in a child I/O
962 }
963 
964 template <Direction DIR>
965 bool ChildUnformattedIoStatementState<DIR>::Receive(
966     char *data, std::size_t bytes, std::size_t elementBytes) {
967   return this->child().parent().Receive(data, bytes, elementBytes);
968 }
969 
970 template class InternalIoStatementState<Direction::Output>;
971 template class InternalIoStatementState<Direction::Input>;
972 template class InternalFormattedIoStatementState<Direction::Output>;
973 template class InternalFormattedIoStatementState<Direction::Input>;
974 template class InternalListIoStatementState<Direction::Output>;
975 template class InternalListIoStatementState<Direction::Input>;
976 template class ExternalIoStatementState<Direction::Output>;
977 template class ExternalIoStatementState<Direction::Input>;
978 template class ExternalFormattedIoStatementState<Direction::Output>;
979 template class ExternalFormattedIoStatementState<Direction::Input>;
980 template class ExternalListIoStatementState<Direction::Output>;
981 template class ExternalListIoStatementState<Direction::Input>;
982 template class ExternalUnformattedIoStatementState<Direction::Output>;
983 template class ExternalUnformattedIoStatementState<Direction::Input>;
984 template class ChildIoStatementState<Direction::Output>;
985 template class ChildIoStatementState<Direction::Input>;
986 template class ChildFormattedIoStatementState<Direction::Output>;
987 template class ChildFormattedIoStatementState<Direction::Input>;
988 template class ChildListIoStatementState<Direction::Output>;
989 template class ChildListIoStatementState<Direction::Input>;
990 template class ChildUnformattedIoStatementState<Direction::Output>;
991 template class ChildUnformattedIoStatementState<Direction::Input>;
992 
993 void ExternalMiscIoStatementState::CompleteOperation() {
994   if (completedOperation()) {
995     return;
996   }
997   ExternalFileUnit &ext{unit()};
998   switch (which_) {
999   case Flush:
1000     ext.FlushOutput(*this);
1001     std::fflush(nullptr); // flushes C stdio output streams (12.9(2))
1002     break;
1003   case Backspace:
1004     ext.BackspaceRecord(*this);
1005     break;
1006   case Endfile:
1007     ext.Endfile(*this);
1008     break;
1009   case Rewind:
1010     ext.Rewind(*this);
1011     break;
1012   }
1013   return IoStatementBase::CompleteOperation();
1014 }
1015 
1016 int ExternalMiscIoStatementState::EndIoStatement() {
1017   CompleteOperation();
1018   return ExternalIoStatementBase::EndIoStatement();
1019 }
1020 
1021 InquireUnitState::InquireUnitState(
1022     ExternalFileUnit &unit, const char *sourceFile, int sourceLine)
1023     : ExternalIoStatementBase{unit, sourceFile, sourceLine} {}
1024 
1025 bool InquireUnitState::Inquire(
1026     InquiryKeywordHash inquiry, char *result, std::size_t length) {
1027   if (unit().createdForInternalChildIo()) {
1028     SignalError(IostatInquireInternalUnit,
1029         "INQUIRE of unit created for defined derived type I/O of an internal "
1030         "unit");
1031     return false;
1032   }
1033   const char *str{nullptr};
1034   switch (inquiry) {
1035   case HashInquiryKeyword("ACCESS"):
1036     if (!unit().IsConnected()) {
1037       str = "UNDEFINED";
1038     } else {
1039       switch (unit().access) {
1040       case Access::Sequential:
1041         str = "SEQUENTIAL";
1042         break;
1043       case Access::Direct:
1044         str = "DIRECT";
1045         break;
1046       case Access::Stream:
1047         str = "STREAM";
1048         break;
1049       }
1050     }
1051     break;
1052   case HashInquiryKeyword("ACTION"):
1053     str = !unit().IsConnected() ? "UNDEFINED"
1054         : unit().mayWrite()     ? unit().mayRead() ? "READWRITE" : "WRITE"
1055                                 : "READ";
1056     break;
1057   case HashInquiryKeyword("ASYNCHRONOUS"):
1058     str = !unit().IsConnected()    ? "UNDEFINED"
1059         : unit().mayAsynchronous() ? "YES"
1060                                    : "NO";
1061     break;
1062   case HashInquiryKeyword("BLANK"):
1063     str = !unit().IsConnected() || unit().isUnformatted.value_or(true)
1064         ? "UNDEFINED"
1065         : unit().modes.editingFlags & blankZero ? "ZERO"
1066                                                 : "NULL";
1067     break;
1068   case HashInquiryKeyword("CARRIAGECONTROL"):
1069     str = "LIST";
1070     break;
1071   case HashInquiryKeyword("CONVERT"):
1072     str = unit().swapEndianness() ? "SWAP" : "NATIVE";
1073     break;
1074   case HashInquiryKeyword("DECIMAL"):
1075     str = !unit().IsConnected() || unit().isUnformatted.value_or(true)
1076         ? "UNDEFINED"
1077         : unit().modes.editingFlags & decimalComma ? "COMMA"
1078                                                    : "POINT";
1079     break;
1080   case HashInquiryKeyword("DELIM"):
1081     if (!unit().IsConnected() || unit().isUnformatted.value_or(true)) {
1082       str = "UNDEFINED";
1083     } else {
1084       switch (unit().modes.delim) {
1085       case '\'':
1086         str = "APOSTROPHE";
1087         break;
1088       case '"':
1089         str = "QUOTE";
1090         break;
1091       default:
1092         str = "NONE";
1093         break;
1094       }
1095     }
1096     break;
1097   case HashInquiryKeyword("DIRECT"):
1098     str = !unit().IsConnected() ? "UNKNOWN"
1099         : unit().access == Access::Direct ||
1100             (unit().mayPosition() && unit().openRecl)
1101         ? "YES"
1102         : "NO";
1103     break;
1104   case HashInquiryKeyword("ENCODING"):
1105     str = !unit().IsConnected()               ? "UNKNOWN"
1106         : unit().isUnformatted.value_or(true) ? "UNDEFINED"
1107         : unit().isUTF8                       ? "UTF-8"
1108                                               : "ASCII";
1109     break;
1110   case HashInquiryKeyword("FORM"):
1111     str = !unit().IsConnected() || !unit().isUnformatted ? "UNDEFINED"
1112         : *unit().isUnformatted                          ? "UNFORMATTED"
1113                                                          : "FORMATTED";
1114     break;
1115   case HashInquiryKeyword("FORMATTED"):
1116     str = !unit().IsConnected() ? "UNDEFINED"
1117         : !unit().isUnformatted ? "UNKNOWN"
1118         : *unit().isUnformatted ? "NO"
1119                                 : "YES";
1120     break;
1121   case HashInquiryKeyword("NAME"):
1122     str = unit().path();
1123     if (!str) {
1124       return true; // result is undefined
1125     }
1126     break;
1127   case HashInquiryKeyword("PAD"):
1128     str = !unit().IsConnected() || unit().isUnformatted.value_or(true)
1129         ? "UNDEFINED"
1130         : unit().modes.pad ? "YES"
1131                            : "NO";
1132     break;
1133   case HashInquiryKeyword("POSITION"):
1134     if (!unit().IsConnected() || unit().access == Access::Direct) {
1135       str = "UNDEFINED";
1136     } else {
1137       switch (unit().InquirePosition()) {
1138       case Position::Rewind:
1139         str = "REWIND";
1140         break;
1141       case Position::Append:
1142         str = "APPEND";
1143         break;
1144       case Position::AsIs:
1145         str = "ASIS";
1146         break;
1147       }
1148     }
1149     break;
1150   case HashInquiryKeyword("READ"):
1151     str = !unit().IsConnected() ? "UNDEFINED" : unit().mayRead() ? "YES" : "NO";
1152     break;
1153   case HashInquiryKeyword("READWRITE"):
1154     str = !unit().IsConnected()                 ? "UNDEFINED"
1155         : unit().mayRead() && unit().mayWrite() ? "YES"
1156                                                 : "NO";
1157     break;
1158   case HashInquiryKeyword("ROUND"):
1159     if (!unit().IsConnected() || unit().isUnformatted.value_or(true)) {
1160       str = "UNDEFINED";
1161     } else {
1162       switch (unit().modes.round) {
1163       case decimal::FortranRounding::RoundNearest:
1164         str = "NEAREST";
1165         break;
1166       case decimal::FortranRounding::RoundUp:
1167         str = "UP";
1168         break;
1169       case decimal::FortranRounding::RoundDown:
1170         str = "DOWN";
1171         break;
1172       case decimal::FortranRounding::RoundToZero:
1173         str = "ZERO";
1174         break;
1175       case decimal::FortranRounding::RoundCompatible:
1176         str = "COMPATIBLE";
1177         break;
1178       }
1179     }
1180     break;
1181   case HashInquiryKeyword("SEQUENTIAL"):
1182     // "NO" for Direct, since Sequential would not work if
1183     // the unit were reopened without RECL=.
1184     str = !unit().IsConnected()               ? "UNKNOWN"
1185         : unit().access == Access::Sequential ? "YES"
1186                                               : "NO";
1187     break;
1188   case HashInquiryKeyword("SIGN"):
1189     str = !unit().IsConnected() || unit().isUnformatted.value_or(true)
1190         ? "UNDEFINED"
1191         : unit().modes.editingFlags & signPlus ? "PLUS"
1192                                                : "SUPPRESS";
1193     break;
1194   case HashInquiryKeyword("STREAM"):
1195     str = !unit().IsConnected()           ? "UNKNOWN"
1196         : unit().access == Access::Stream ? "YES"
1197                                           : "NO";
1198     break;
1199   case HashInquiryKeyword("UNFORMATTED"):
1200     str = !unit().IsConnected() || !unit().isUnformatted ? "UNKNOWN"
1201         : *unit().isUnformatted                          ? "YES"
1202                                                          : "NO";
1203     break;
1204   case HashInquiryKeyword("WRITE"):
1205     str = !unit().IsConnected() ? "UNKNOWN" : unit().mayWrite() ? "YES" : "NO";
1206     break;
1207   }
1208   if (str) {
1209     ToFortranDefaultCharacter(result, length, str);
1210     return true;
1211   } else {
1212     BadInquiryKeywordHashCrash(inquiry);
1213     return false;
1214   }
1215 }
1216 
1217 bool InquireUnitState::Inquire(InquiryKeywordHash inquiry, bool &result) {
1218   switch (inquiry) {
1219   case HashInquiryKeyword("EXIST"):
1220     result = true;
1221     return true;
1222   case HashInquiryKeyword("NAMED"):
1223     result = unit().path() != nullptr;
1224     return true;
1225   case HashInquiryKeyword("OPENED"):
1226     result = unit().IsConnected();
1227     return true;
1228   case HashInquiryKeyword("PENDING"):
1229     result = false; // asynchronous I/O is not implemented
1230     return true;
1231   default:
1232     BadInquiryKeywordHashCrash(inquiry);
1233     return false;
1234   }
1235 }
1236 
1237 bool InquireUnitState::Inquire(
1238     InquiryKeywordHash inquiry, std::int64_t, bool &result) {
1239   switch (inquiry) {
1240   case HashInquiryKeyword("PENDING"):
1241     result = false; // asynchronous I/O is not implemented
1242     return true;
1243   default:
1244     BadInquiryKeywordHashCrash(inquiry);
1245     return false;
1246   }
1247 }
1248 
1249 bool InquireUnitState::Inquire(
1250     InquiryKeywordHash inquiry, std::int64_t &result) {
1251   switch (inquiry) {
1252   case HashInquiryKeyword("NEXTREC"):
1253     if (unit().access == Access::Direct) {
1254       result = unit().currentRecordNumber;
1255     }
1256     return true;
1257   case HashInquiryKeyword("NUMBER"):
1258     result = unit().IsConnected() ? unit().unitNumber() : -1;
1259     return true;
1260   case HashInquiryKeyword("POS"):
1261     result = unit().InquirePos();
1262     return true;
1263   case HashInquiryKeyword("RECL"):
1264     if (!unit().IsConnected()) {
1265       result = -1;
1266     } else if (unit().access == Access::Stream) {
1267       result = -2;
1268     } else if (unit().openRecl) {
1269       result = *unit().openRecl;
1270     } else {
1271       result = std::numeric_limits<std::int32_t>::max();
1272     }
1273     return true;
1274   case HashInquiryKeyword("SIZE"):
1275     result = -1;
1276     if (unit().IsConnected()) {
1277       if (auto size{unit().knownSize()}) {
1278         result = *size;
1279       }
1280     }
1281     return true;
1282   default:
1283     BadInquiryKeywordHashCrash(inquiry);
1284     return false;
1285   }
1286 }
1287 
1288 InquireNoUnitState::InquireNoUnitState(const char *sourceFile, int sourceLine)
1289     : NoUnitIoStatementState{sourceFile, sourceLine, *this} {}
1290 
1291 bool InquireNoUnitState::Inquire(
1292     InquiryKeywordHash inquiry, char *result, std::size_t length) {
1293   switch (inquiry) {
1294   case HashInquiryKeyword("ACCESS"):
1295   case HashInquiryKeyword("ACTION"):
1296   case HashInquiryKeyword("ASYNCHRONOUS"):
1297   case HashInquiryKeyword("BLANK"):
1298   case HashInquiryKeyword("CARRIAGECONTROL"):
1299   case HashInquiryKeyword("CONVERT"):
1300   case HashInquiryKeyword("DECIMAL"):
1301   case HashInquiryKeyword("DELIM"):
1302   case HashInquiryKeyword("FORM"):
1303   case HashInquiryKeyword("NAME"):
1304   case HashInquiryKeyword("PAD"):
1305   case HashInquiryKeyword("POSITION"):
1306   case HashInquiryKeyword("ROUND"):
1307   case HashInquiryKeyword("SIGN"):
1308     ToFortranDefaultCharacter(result, length, "UNDEFINED");
1309     return true;
1310   case HashInquiryKeyword("DIRECT"):
1311   case HashInquiryKeyword("ENCODING"):
1312   case HashInquiryKeyword("FORMATTED"):
1313   case HashInquiryKeyword("READ"):
1314   case HashInquiryKeyword("READWRITE"):
1315   case HashInquiryKeyword("SEQUENTIAL"):
1316   case HashInquiryKeyword("STREAM"):
1317   case HashInquiryKeyword("WRITE"):
1318   case HashInquiryKeyword("UNFORMATTED"):
1319     ToFortranDefaultCharacter(result, length, "UNKNONN");
1320     return true;
1321   default:
1322     BadInquiryKeywordHashCrash(inquiry);
1323     return false;
1324   }
1325 }
1326 
1327 bool InquireNoUnitState::Inquire(InquiryKeywordHash inquiry, bool &result) {
1328   switch (inquiry) {
1329   case HashInquiryKeyword("EXIST"):
1330     result = true;
1331     return true;
1332   case HashInquiryKeyword("NAMED"):
1333   case HashInquiryKeyword("OPENED"):
1334   case HashInquiryKeyword("PENDING"):
1335     result = false;
1336     return true;
1337   default:
1338     BadInquiryKeywordHashCrash(inquiry);
1339     return false;
1340   }
1341 }
1342 
1343 bool InquireNoUnitState::Inquire(
1344     InquiryKeywordHash inquiry, std::int64_t, bool &result) {
1345   switch (inquiry) {
1346   case HashInquiryKeyword("PENDING"):
1347     result = false;
1348     return true;
1349   default:
1350     BadInquiryKeywordHashCrash(inquiry);
1351     return false;
1352   }
1353 }
1354 
1355 bool InquireNoUnitState::Inquire(
1356     InquiryKeywordHash inquiry, std::int64_t &result) {
1357   switch (inquiry) {
1358   case HashInquiryKeyword("NEXTREC"):
1359   case HashInquiryKeyword("NUMBER"):
1360   case HashInquiryKeyword("POS"):
1361   case HashInquiryKeyword("RECL"):
1362   case HashInquiryKeyword("SIZE"):
1363     result = -1;
1364     return true;
1365   default:
1366     BadInquiryKeywordHashCrash(inquiry);
1367     return false;
1368   }
1369 }
1370 
1371 InquireUnconnectedFileState::InquireUnconnectedFileState(
1372     OwningPtr<char> &&path, const char *sourceFile, int sourceLine)
1373     : NoUnitIoStatementState{sourceFile, sourceLine, *this}, path_{std::move(
1374                                                                  path)} {}
1375 
1376 bool InquireUnconnectedFileState::Inquire(
1377     InquiryKeywordHash inquiry, char *result, std::size_t length) {
1378   const char *str{nullptr};
1379   switch (inquiry) {
1380   case HashInquiryKeyword("ACCESS"):
1381   case HashInquiryKeyword("ACTION"):
1382   case HashInquiryKeyword("ASYNCHRONOUS"):
1383   case HashInquiryKeyword("BLANK"):
1384   case HashInquiryKeyword("CARRIAGECONTROL"):
1385   case HashInquiryKeyword("CONVERT"):
1386   case HashInquiryKeyword("DECIMAL"):
1387   case HashInquiryKeyword("DELIM"):
1388   case HashInquiryKeyword("FORM"):
1389   case HashInquiryKeyword("PAD"):
1390   case HashInquiryKeyword("POSITION"):
1391   case HashInquiryKeyword("ROUND"):
1392   case HashInquiryKeyword("SIGN"):
1393     str = "UNDEFINED";
1394     break;
1395   case HashInquiryKeyword("DIRECT"):
1396   case HashInquiryKeyword("ENCODING"):
1397   case HashInquiryKeyword("FORMATTED"):
1398   case HashInquiryKeyword("SEQUENTIAL"):
1399   case HashInquiryKeyword("STREAM"):
1400   case HashInquiryKeyword("UNFORMATTED"):
1401     str = "UNKNONN";
1402     break;
1403   case HashInquiryKeyword("READ"):
1404     str = MayRead(path_.get()) ? "YES" : "NO";
1405     break;
1406   case HashInquiryKeyword("READWRITE"):
1407     str = MayReadAndWrite(path_.get()) ? "YES" : "NO";
1408     break;
1409   case HashInquiryKeyword("WRITE"):
1410     str = MayWrite(path_.get()) ? "YES" : "NO";
1411     break;
1412   case HashInquiryKeyword("NAME"):
1413     str = path_.get();
1414     if (!str) {
1415       return true; // result is undefined
1416     }
1417     break;
1418   }
1419   if (str) {
1420     ToFortranDefaultCharacter(result, length, str);
1421     return true;
1422   } else {
1423     BadInquiryKeywordHashCrash(inquiry);
1424     return false;
1425   }
1426 }
1427 
1428 bool InquireUnconnectedFileState::Inquire(
1429     InquiryKeywordHash inquiry, bool &result) {
1430   switch (inquiry) {
1431   case HashInquiryKeyword("EXIST"):
1432     result = IsExtant(path_.get());
1433     return true;
1434   case HashInquiryKeyword("NAMED"):
1435     result = true;
1436     return true;
1437   case HashInquiryKeyword("OPENED"):
1438     result = false;
1439     return true;
1440   case HashInquiryKeyword("PENDING"):
1441     result = false;
1442     return true;
1443   default:
1444     BadInquiryKeywordHashCrash(inquiry);
1445     return false;
1446   }
1447 }
1448 
1449 bool InquireUnconnectedFileState::Inquire(
1450     InquiryKeywordHash inquiry, std::int64_t, bool &result) {
1451   switch (inquiry) {
1452   case HashInquiryKeyword("PENDING"):
1453     result = false;
1454     return true;
1455   default:
1456     BadInquiryKeywordHashCrash(inquiry);
1457     return false;
1458   }
1459 }
1460 
1461 bool InquireUnconnectedFileState::Inquire(
1462     InquiryKeywordHash inquiry, std::int64_t &result) {
1463   switch (inquiry) {
1464   case HashInquiryKeyword("NEXTREC"):
1465   case HashInquiryKeyword("NUMBER"):
1466   case HashInquiryKeyword("POS"):
1467   case HashInquiryKeyword("RECL"):
1468   case HashInquiryKeyword("SIZE"):
1469     result = -1;
1470     return true;
1471   default:
1472     BadInquiryKeywordHashCrash(inquiry);
1473     return false;
1474   }
1475 }
1476 
1477 InquireIOLengthState::InquireIOLengthState(
1478     const char *sourceFile, int sourceLine)
1479     : NoUnitIoStatementState{sourceFile, sourceLine, *this} {}
1480 
1481 bool InquireIOLengthState::Emit(const char *, std::size_t n, std::size_t) {
1482   bytes_ += n;
1483   return true;
1484 }
1485 
1486 bool InquireIOLengthState::Emit(const char *p, std::size_t n) {
1487   bytes_ += sizeof *p * n;
1488   return true;
1489 }
1490 
1491 bool InquireIOLengthState::Emit(const char16_t *p, std::size_t n) {
1492   bytes_ += sizeof *p * n;
1493   return true;
1494 }
1495 
1496 bool InquireIOLengthState::Emit(const char32_t *p, std::size_t n) {
1497   bytes_ += sizeof *p * n;
1498   return true;
1499 }
1500 
1501 int ErroneousIoStatementState::EndIoStatement() {
1502   SignalPendingError();
1503   return IoStatementBase::EndIoStatement();
1504 }
1505 
1506 template bool IoStatementState::EmitEncoded<char>(const char *, std::size_t);
1507 template bool IoStatementState::EmitEncoded<char16_t>(
1508     const char16_t *, std::size_t);
1509 template bool IoStatementState::EmitEncoded<char32_t>(
1510     const char32_t *, std::size_t);
1511 
1512 } // namespace Fortran::runtime::io
1513