linux-sgx-trts-modified/sdk/cpprt/memory_manage/new_handler.cpp

/*
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#include <stdlib.h>
#include <new>
#include "sgx_trts.h"
#include "sgx_spinlock.h"
#include "internal/se_cdefs.h"

namespace std{
    static sgx_spinlock_t handler_lock = SGX_SPINLOCK_INITIALIZER;
    //default hanlder is NULL
    static new_handler new_handl = NULL;

    // set_new_handler()
    //      Sets new_p as the new handler function.
    //      The new handler function is the function that is called by functions 
    //      operator new or operator new[] when they are not successful 
    //      in an attempt to allocate memory.
    // Parameter
    //      handler -  a pointer to the handler to be called.
    //					  The function can make more storage available or throw an exception or terminate the program.
    //					  new_handler is a function pointer type taking no parameters and returning void.
    // Return Value
    //      new_handler - The value of the current new_handler function if this has been previously set by this function
    //									 NULL -if this is the first call to set_new_handler
    new_handler set_new_handler(new_handler handle) throw()
    {
        sgx_spin_lock(&handler_lock);
        new_handler retHandle = new_handl;
        if ( handle == NULL ){
            new_handl = NULL;
        } else if ( sgx_is_within_enclave((void *)handle, 0) ){
            //only set the handler when handler address is inside enclave
            new_handl = handle;
        }
        sgx_spin_unlock(&handler_lock);
        return retHandle;
    }
};

using namespace std;

//call new_handl function when  new memory failed
int  call_newh()
{
    int ret = 0;
    sgx_spin_lock(&handler_lock);
    new_handler handler = new_handl;
    //unlock the handler here because new_handl may call set_new_handler again, will cause dead lock.
    sgx_spin_unlock(&handler_lock);

    // call new handler
    if ( handler != NULL ){
        handler();
        ret = 1;
    }
   
    return ret;
}