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#include "test.h"
#include <stdint.h>
#include <stddef.h>
typedef uint64_t Datum;
typedef void (*pg_on_exit_callback)(int code, Datum arg);
struct ONEXIT {
pg_on_exit_callback function;
Datum arg;
};
// Simulate Int32GetDatum macro from PostgreSQL
static inline Datum Int32GetDatum(int32_t i) {
return (Datum)(uint32_t)i; // cast to 32-bit first, then 64-bit Datum
}
// Dummy callback function
void dummy_callback(int code, Datum arg) {
printf("dummy_callback called with code=%d, arg=0x%lx\n", code, arg);
}
int main() {
struct ONEXIT onexit;
onexit.function = dummy_callback;
onexit.arg = Int32GetDatum(123456789);
printf("sizeof(ONEXIT) = %zu\n", sizeof(struct ONEXIT));
printf("offset function = %zu\n", offsetof(struct ONEXIT, function));
printf("offset arg = %zu\n", offsetof(struct ONEXIT, arg));
ASSERT(16, sizeof(struct ONEXIT));
ASSERT(0, offsetof(struct ONEXIT, function));
ASSERT(8, offsetof(struct ONEXIT, arg));
// Call the callback to see the stored value
onexit.function(0, onexit.arg);
return 0;
}
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