| //===-- runtime/unit-map.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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "unit-map.h" |
| #include "flang/Common/optional.h" |
| |
| namespace Fortran::runtime::io { |
| |
| void UnitMap::Initialize() { |
| if (!isInitialized_) { |
| freeNewUnits_.InitializeState(); |
| // Unit number -1 is reserved. |
| // The unit numbers are pushed in reverse order so that the first |
| // ones to be popped will be small and suitable for use as kind=1 |
| // integers. |
| for (int j{freeNewUnits_.maxValue}; j > 1; --j) { |
| freeNewUnits_.Add(j); |
| } |
| isInitialized_ = true; |
| } |
| } |
| |
| // See 12.5.6.12 in Fortran 2018. NEWUNIT= unit numbers are negative, |
| // and not equal to -1 (or ERROR_UNIT, if it were negative, which it isn't.) |
| ExternalFileUnit &UnitMap::NewUnit(const Terminator &terminator) { |
| CriticalSection critical{lock_}; |
| Initialize(); |
| Fortran::common::optional<int> n{freeNewUnits_.PopValue()}; |
| if (!n) { |
| n = emergencyNewUnit_++; |
| } |
| return Create(-*n, terminator); |
| } |
| |
| ExternalFileUnit *UnitMap::LookUpForClose(int n) { |
| CriticalSection critical{lock_}; |
| Chain *previous{nullptr}; |
| int hash{Hash(n)}; |
| for (Chain *p{bucket_[hash].get()}; p; previous = p, p = p->next.get()) { |
| if (p->unit.unitNumber() == n) { |
| if (previous) { |
| previous->next.swap(p->next); |
| } else { |
| bucket_[hash].swap(p->next); |
| } |
| // p->next.get() == p at this point; the next swap pushes p on closing_ |
| closing_.swap(p->next); |
| return &p->unit; |
| } |
| } |
| return nullptr; |
| } |
| |
| void UnitMap::DestroyClosed(ExternalFileUnit &unit) { |
| Chain *p{nullptr}; |
| { |
| CriticalSection critical{lock_}; |
| Chain *previous{nullptr}; |
| for (p = closing_.get(); p; previous = p, p = p->next.get()) { |
| if (&p->unit == &unit) { |
| int n{unit.unitNumber()}; |
| if (n <= -2) { |
| freeNewUnits_.Add(-n); |
| } |
| if (previous) { |
| previous->next.swap(p->next); |
| } else { |
| closing_.swap(p->next); |
| } |
| break; |
| } |
| } |
| } |
| if (p) { |
| p->unit.~ExternalFileUnit(); |
| FreeMemory(p); |
| } |
| } |
| |
| void UnitMap::CloseAll(IoErrorHandler &handler) { |
| // Extract units from the map so they can be closed |
| // without holding lock_. |
| OwningPtr<Chain> closeList; |
| { |
| CriticalSection critical{lock_}; |
| for (int j{0}; j < buckets_; ++j) { |
| while (Chain * p{bucket_[j].get()}) { |
| bucket_[j].swap(p->next); // pops p from head of bucket list |
| closeList.swap(p->next); // pushes p to closeList |
| } |
| } |
| } |
| while (Chain * p{closeList.get()}) { |
| closeList.swap(p->next); // pops p from head of closeList |
| p->unit.CloseUnit(CloseStatus::Keep, handler); |
| p->unit.~ExternalFileUnit(); |
| FreeMemory(p); |
| } |
| } |
| |
| void UnitMap::FlushAll(IoErrorHandler &handler) { |
| CriticalSection critical{lock_}; |
| for (int j{0}; j < buckets_; ++j) { |
| for (Chain *p{bucket_[j].get()}; p; p = p->next.get()) { |
| p->unit.FlushOutput(handler); |
| } |
| } |
| } |
| |
| ExternalFileUnit *UnitMap::Find(const char *path, std::size_t pathLen) { |
| if (path) { |
| // TODO: Faster data structure |
| for (int j{0}; j < buckets_; ++j) { |
| for (Chain *p{bucket_[j].get()}; p; p = p->next.get()) { |
| if (p->unit.path() && p->unit.pathLength() == pathLen && |
| std::memcmp(p->unit.path(), path, pathLen) == 0) { |
| return &p->unit; |
| } |
| } |
| } |
| } |
| return nullptr; |
| } |
| |
| ExternalFileUnit &UnitMap::Create(int n, const Terminator &terminator) { |
| Chain &chain{*New<Chain>{terminator}(n).release()}; |
| chain.next.reset(&chain); |
| bucket_[Hash(n)].swap(chain.next); // pushes new node as list head |
| return chain.unit; |
| } |
| |
| } // namespace Fortran::runtime::io |