177af53578
* Remove the unused EnsureDarwinMachPorts function When compiling the C++ shims for longjmp/setjmp/signal handling we don't use the `USE_APPLE_MACH_PORTS` directive, so this function was entirely unused anyway. This looks to be a holdover from when this was originally copied from C++, but no need for keeping around this now-legacy initialization. * Remove the `wasmtime_init_finish` function This looks like it's perhaps largely historical cruft at this point now I think? The function, with the removal of the mach ports from the previous commit, only reads the initializtion state of the signal handlers. If the signal handlers failed to get installed, though, it simply returns early rather than erroring out anyway. In any case a follow-up commit will refactor `wasmtime_init_eager` to handle this as well. * Pare down `wasmtime_init_eager` Similar to previous commits it looks like this function may have accrued some debt over time, nowadays it doesn't really do much other than capture a backtrace and install signal handlers. The `lazy_static` state isn't really that necessary and we can rely on the `Once` primitive in the standard library for one-time initialization. This also updates the code to unconditionally panic if signal handlers fail to get installed, which I think is the behavior that we'll want for now and we can enhance it over time if necessary, but I don't think we have a use case where it's currently necessary.
48 lines
1.3 KiB
C++
48 lines
1.3 KiB
C++
#ifndef signal_handlers_h
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#define signal_handlers_h
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#include <stdint.h>
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#include <setjmp.h>
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#ifndef __cplusplus
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#include <stdbool.h>
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#endif
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#include <signal.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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// Record the Trap code and wasm bytecode offset in TLS somewhere
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void* RecordTrap(const uint8_t* pc, bool reset_guard_page);
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#if defined(_WIN32)
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#include <windows.h>
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#include <winternl.h>
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bool InstanceSignalHandler(LPEXCEPTION_POINTERS);
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#elif defined(USE_APPLE_MACH_PORTS)
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bool InstanceSignalHandler(int, siginfo_t *, void *);
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#else
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#include <sys/ucontext.h>
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bool InstanceSignalHandler(int, siginfo_t *, ucontext_t *);
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#endif
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void Unwind(void*);
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// This function performs the low-overhead signal handler initialization that we
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// want to do eagerly to ensure a more-deterministic global process state. This
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// is especially relevant for signal handlers since handler ordering depends on
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// installation order: the wasm signal handler must run *before* the other crash
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// handlers and since POSIX signal handlers work LIFO, this function needs to be
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// called at the end of the startup process, after other handlers have been
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// installed. This function can thus be called multiple times, having no effect
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// after the first call.
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int
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EnsureEagerSignalHandlers(void);
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#ifdef __cplusplus
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} // extern "C"
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#endif
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#endif // signal_handlers_h
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