1 //===-- runtime/io-error.h --------------------------------------*- 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 // Distinguishes I/O error conditions; fatal ones lead to termination,
10 // and those that the user program has chosen to handle are recorded
11 // so that the highest-priority one can be returned as IOSTAT=.
12 // IOSTAT error codes are raw errno values augmented with values for
13 // Fortran-specific errors.
14 
15 #ifndef FORTRAN_RUNTIME_IO_ERROR_H_
16 #define FORTRAN_RUNTIME_IO_ERROR_H_
17 
18 #include "terminator.h"
19 #include "flang/Runtime/iostat.h"
20 #include "flang/Runtime/memory.h"
21 #include <cinttypes>
22 
23 namespace Fortran::runtime::io {
24 
25 // See 12.11 in Fortran 2018
26 class IoErrorHandler : public Terminator {
27 public:
28   using Terminator::Terminator;
29   explicit IoErrorHandler(const Terminator &that) : Terminator{that} {}
30   void HasIoStat() { flags_ |= hasIoStat; }
31   void HasErrLabel() { flags_ |= hasErr; }
32   void HasEndLabel() { flags_ |= hasEnd; }
33   void HasEorLabel() { flags_ |= hasEor; }
34   void HasIoMsg() { flags_ |= hasIoMsg; }
35   void HandleAnything() {
36     flags_ = hasIoStat | hasErr | hasEnd | hasEor | hasIoMsg;
37   }
38 
39   bool InError() const {
40     return ioStat_ != IostatOk || pendingError_ != IostatOk;
41   }
42 
43   // For I/O statements that detect fatal errors in their
44   // Begin...() API routines before it is known whether they
45   // have error handling control list items.  Such statements
46   // have an ErroneousIoStatementState with a pending error.
47   void SetPendingError(int iostat) { pendingError_ = iostat; }
48 
49   void SignalError(int iostatOrErrno, const char *msg, ...);
50   void SignalError(int iostatOrErrno);
51   template <typename... X> void SignalError(const char *msg, X &&...xs) {
52     SignalError(IostatGenericError, msg, std::forward<X>(xs)...);
53   }
54 
55   void Forward(int iostatOrErrno, const char *, std::size_t);
56 
57   void SignalErrno(); // SignalError(errno)
58   void SignalEnd(); // input only; EOF on internal write is an error
59   void SignalEor(); // non-advancing input only; EOR on write is an error
60   void SignalPendingError();
61 
62   int GetIoStat() const { return ioStat_; }
63   bool GetIoMsg(char *, std::size_t);
64 
65 private:
66   enum Flag : std::uint8_t {
67     hasIoStat = 1, // IOSTAT=
68     hasErr = 2, // ERR=
69     hasEnd = 4, // END=
70     hasEor = 8, // EOR=
71     hasIoMsg = 16, // IOMSG=
72   };
73   std::uint8_t flags_{0};
74   int ioStat_{IostatOk};
75   OwningPtr<char> ioMsg_;
76   int pendingError_{IostatOk};
77 };
78 
79 } // namespace Fortran::runtime::io
80 #endif // FORTRAN_RUNTIME_IO_ERROR_H_
81