PHP Embed SAPI not saving and restoring signal handlers.

Description

I would expect the the execution context to be restored following the PHP_EMBED_END_BLOCK() macro, but this doesn't seem to be the case for signal handlers.

here is a toy function to call a php function from a specified file:

/* Early work to call a php function from a specified script file */
void
call_php_function(char *file_name, char *function_name)
{
    zend_file_handle file_handle;
    zval retval = {0};
    zend_fcall_info fci = {0};
    zend_fcall_info_cache fci_cache = {0};

    sigset_t       oldsigset;
    struct sigaction oldsigaction[32] = {0,};

    some_signal_save_function(&oldsigset, oldsigaction);

    PHP_EMBED_START_BLOCK(0, NULL)
        zend_stream_init_filename(&file_handle, file_name);

        php_execute_script(&file_handle);

        ZVAL_STRING(&fci.function_name, function_name);

        fci.size = sizeof fci;
        fci.retval = &retval;

        zend_call_function(&fci, &fci_cache);
    PHP_EMBED_END_BLOCK()

    some_signal_restore_function(&oldsigset, oldsigaction);
}

Without the signal save/restore wrapping the embed block, the zend_signal_handler and defer handler is still handling the dispatching of signals, which is likely not what a user would want once outside an embed block.

PHP Version

7.4.27

Operating System

No response

Start with the PHP_EMBED_START_BLOCK() and PHP_EMBED_END_BLOCK() macros and trace how zend_signal_handler and the defer handler are installed and removed. Compare the signal state before and after an embed block; done means signal handlers and deferred signal handling are restored for the surrounding process after PHP_EMBED_END_BLOCK().