safefetch_sigjmp.hpp

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#ifndef OS_POSIX_SAFEFETCH_SIGJMP_HPP
#define OS_POSIX_SAFEFETCH_SIGJMP_HPP

#include "utilities/globalDefinitions.hpp"

// On Posix platforms that don't do anything better - or cannot, like Zero -
// SafeFetch is implemented using setjmp/longjmp. That is reliable and portable,
// but slower than other methods, and needs more thread stack (the sigjmp buffer
// lives on the thread stack).

int SafeFetch32_impl(int* adr, int errValue);
intptr_t SafeFetchN_impl(intptr_t* adr, intptr_t errValue);

// Handle safefetch, sigsetjmp style. Only call from signal handler.
// If a safefetch jump had been established and the sig qualifies, we
// jump back to the established jump point (and hence out of signal handling).
bool handle_safefetch(int sig, address pc, void* context);

#endif // OS_POSIX_SAFEFETCH_SIGJMP_HPP