exception.h

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//
// Copyright 2021 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
 
#ifndef PXR_BASE_TF_EXCEPTION_H
#define PXR_BASE_TF_EXCEPTION_H
 
 
#include "pxr/pxr.h"
#include "pxr/base/tf/api.h"
#include "pxr/base/tf/callContext.h"
#include "pxr/base/tf/functionRef.h"
 
#include <cstdint>
#include <exception>
#include <string>
#include <vector>
 
PXR_NAMESPACE_OPEN_SCOPE
 
struct TfSkipCallerFrames
{
    explicit TfSkipCallerFrames(int n=0) : numToSkip(n) {}
    int numToSkip;
};
 
class TfBaseException : public std::exception
{
public:
    TF_API
    virtual ~TfBaseException();
 
    TF_API
    explicit TfBaseException(std::string const &message);
 
    TfCallContext const &GetThrowContext() const {
        return _callContext;
    }
 
    std::vector<uintptr_t> const &GetThrowStack() const {
        return _throwStack;
    }
 
    void MoveThrowStackTo(std::vector<uintptr_t> &out) {
        out = std::move(_throwStack);
        _throwStack.clear();
    }
 
    TF_API
    virtual const char *what() const noexcept override;
 
    // Friend throw support.
    template <class Derived, class ... Args>
    friend void
    Tf_Throw(TfCallContext const &cc,
             TfSkipCallerFrames skipFrames,
             Args && ... args);
 
private:
    TF_API
    static void _ThrowImpl(TfCallContext const &cc,
                           TfBaseException &exc,
                           TfFunctionRef<void ()> thrower,
                           int skipNCallerFrames);
 
    TfCallContext _callContext;
    std::vector<uintptr_t> _throwStack;
    std::string _message;
};
 
// TF_THROW() support function.
template <class Exception, class ... Args>
void
Tf_Throw(TfCallContext const &cc,
         TfSkipCallerFrames skipFrames,
         Args && ... args) {
    Exception exc(std::forward<Args>(args)...);
    auto thrower = [&exc]() { throw std::move(exc); };
    TfBaseException::_ThrowImpl(cc, exc, thrower, skipFrames.numToSkip);
}        
 
// TF_THROW() support function.
template <class Exception, class ... Args>
void Tf_Throw(TfCallContext const &cc, Args && ... args) {
    Tf_Throw<Exception>(cc, TfSkipCallerFrames(), std::forward<Args>(args)...);
}
 
#ifdef doxygen
 
#define TF_THROW(Exception, Exception-ctor-args...)
#define TF_THROW(Exception, TfSkipCallerFrames, Exception-ctor-args...)
 
#else 
 
#define TF_THROW(Exception, ...)                        \
    Tf_Throw<Exception>(TF_CALL_CONTEXT, __VA_ARGS__)
 
#endif
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif // PXR_BASE_TF_EXCEPTION_H