1 //===-- runtime/internal-unit.cpp -------------------------------*- C++ -*-===//
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 "internal-unit.h"
10 #include "descriptor.h"
11 #include "io-error.h"
12 #include <algorithm>
13 #include <type_traits>
14
15 namespace Fortran::runtime::io {
16
17 template <Direction DIR>
InternalDescriptorUnit(Scalar scalar,std::size_t length)18 InternalDescriptorUnit<DIR>::InternalDescriptorUnit(
19 Scalar scalar, std::size_t length) {
20 isFixedRecordLength = true;
21 recordLength = length;
22 endfileRecordNumber = 2;
23 void *pointer{reinterpret_cast<void *>(const_cast<char *>(scalar))};
24 descriptor().Establish(TypeCode{CFI_type_char}, length, pointer, 0, nullptr,
25 CFI_attribute_pointer);
26 }
27
28 template <Direction DIR>
InternalDescriptorUnit(const Descriptor & that,const Terminator & terminator)29 InternalDescriptorUnit<DIR>::InternalDescriptorUnit(
30 const Descriptor &that, const Terminator &terminator) {
31 RUNTIME_CHECK(terminator, that.type().IsCharacter());
32 Descriptor &d{descriptor()};
33 RUNTIME_CHECK(
34 terminator, that.SizeInBytes() <= d.SizeInBytes(maxRank, true, 0));
35 new (&d) Descriptor{that};
36 d.Check();
37 isFixedRecordLength = true;
38 recordLength = d.ElementBytes();
39 endfileRecordNumber = d.Elements() + 1;
40 }
41
EndIoStatement()42 template <Direction DIR> void InternalDescriptorUnit<DIR>::EndIoStatement() {
43 if constexpr (DIR == Direction::Output) { // blank fill
44 while (char *record{CurrentRecord()}) {
45 if (furthestPositionInRecord <
46 recordLength.value_or(furthestPositionInRecord)) {
47 std::fill_n(record + furthestPositionInRecord,
48 *recordLength - furthestPositionInRecord, ' ');
49 }
50 furthestPositionInRecord = 0;
51 ++currentRecordNumber;
52 }
53 }
54 }
55
56 template <Direction DIR>
Emit(const char * data,std::size_t bytes,IoErrorHandler & handler)57 bool InternalDescriptorUnit<DIR>::Emit(
58 const char *data, std::size_t bytes, IoErrorHandler &handler) {
59 if constexpr (DIR == Direction::Input) {
60 handler.Crash("InternalDescriptorUnit<Direction::Input>::Emit() called");
61 return false && data[bytes] != 0; // bogus compare silences GCC warning
62 } else {
63 if (bytes <= 0) {
64 return true;
65 }
66 char *record{CurrentRecord()};
67 if (!record) {
68 handler.SignalError(IostatInternalWriteOverrun);
69 return false;
70 }
71 auto furthestAfter{std::max(furthestPositionInRecord,
72 positionInRecord + static_cast<std::int64_t>(bytes))};
73 bool ok{true};
74 if (furthestAfter > static_cast<std::int64_t>(recordLength.value_or(0))) {
75 handler.SignalError(IostatRecordWriteOverrun);
76 furthestAfter = recordLength.value_or(0);
77 bytes = std::max(std::int64_t{0}, furthestAfter - positionInRecord);
78 ok = false;
79 } else if (positionInRecord > furthestPositionInRecord) {
80 std::fill_n(record + furthestPositionInRecord,
81 positionInRecord - furthestPositionInRecord, ' ');
82 }
83 std::memcpy(record + positionInRecord, data, bytes);
84 positionInRecord += bytes;
85 furthestPositionInRecord = furthestAfter;
86 return ok;
87 }
88 }
89
90 template <Direction DIR>
GetCurrentChar(IoErrorHandler & handler)91 std::optional<char32_t> InternalDescriptorUnit<DIR>::GetCurrentChar(
92 IoErrorHandler &handler) {
93 if constexpr (DIR == Direction::Output) {
94 handler.Crash(
95 "InternalDescriptorUnit<Direction::Output>::GetCurrentChar() called");
96 return std::nullopt;
97 }
98 const char *record{CurrentRecord()};
99 if (!record) {
100 handler.SignalEnd();
101 return std::nullopt;
102 }
103 if (positionInRecord >= recordLength.value_or(positionInRecord)) {
104 return std::nullopt;
105 }
106 if (isUTF8) {
107 // TODO: UTF-8 decoding
108 }
109 return record[positionInRecord];
110 }
111
112 template <Direction DIR>
AdvanceRecord(IoErrorHandler & handler)113 bool InternalDescriptorUnit<DIR>::AdvanceRecord(IoErrorHandler &handler) {
114 if (currentRecordNumber >= endfileRecordNumber.value_or(0)) {
115 handler.SignalEnd();
116 return false;
117 }
118 if constexpr (DIR == Direction::Output) { // blank fill
119 if (furthestPositionInRecord <
120 recordLength.value_or(furthestPositionInRecord)) {
121 char *record{CurrentRecord()};
122 RUNTIME_CHECK(handler, record != nullptr);
123 std::fill_n(record + furthestPositionInRecord,
124 *recordLength - furthestPositionInRecord, ' ');
125 }
126 }
127 ++currentRecordNumber;
128 BeginRecord();
129 return true;
130 }
131
132 template <Direction DIR>
BackspaceRecord(IoErrorHandler & handler)133 void InternalDescriptorUnit<DIR>::BackspaceRecord(IoErrorHandler &handler) {
134 RUNTIME_CHECK(handler, currentRecordNumber > 1);
135 --currentRecordNumber;
136 BeginRecord();
137 }
138
139 template class InternalDescriptorUnit<Direction::Output>;
140 template class InternalDescriptorUnit<Direction::Input>;
141 } // namespace Fortran::runtime::io
142