1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86

use std::ptr;

use log::trace;

use crate::TryIntoJs;
use crate::JSValue;
use crate::sys::napi_value;
use crate::sys::napi_env;
use crate::val::JsEnv;
use crate::NjError;

/// pass rust byte arry as Node.js ArrayBuffer
pub struct ArrayBuffer {
    data: Vec<u8>,
}

impl ArrayBuffer {
    pub fn new(data: Vec<u8>) -> Self {
        Self { data }
    }

    extern "C" fn finalize_buffer(
        _env: napi_env,
        _finalize_data: *mut ::std::os::raw::c_void,
        finalize_hint: *mut ::std::os::raw::c_void,
    ) {
        trace!("finalize array buffer");
        unsafe {
            // use hint to reconstruct box instead of finalize data
            let ptr: *mut Vec<u8> = finalize_hint as *mut Vec<u8>;
            let _rust = Box::from_raw(ptr);
        }
    }
}

impl TryIntoJs for ArrayBuffer {
    fn try_to_js(self, js_env: &JsEnv) -> Result<napi_value, NjError> {
        let len = self.data.len();

        let box_data = Box::new(self.data);

        let mut napi_buffer = ptr::null_mut();

        // get pointer to vec's buffer
        let data_buffer = box_data.as_ptr();

        // get raw pointer to box, this will be used to reconstruct box
        let data_box_ptr = Box::into_raw(box_data) as *mut core::ffi::c_void;

        crate::napi_call_result!(crate::sys::napi_create_external_arraybuffer(
            js_env.inner(),
            data_buffer as *mut core::ffi::c_void,
            len,
            Some(Self::finalize_buffer),
            data_box_ptr,
            &mut napi_buffer
        ))?;

        Ok(napi_buffer)
    }
}

use std::fmt;
use std::fmt::Debug;

impl Debug for ArrayBuffer {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_fmt(format_args!("ArrayBuffer len: {}", self.data.len()))
    }
}

impl<'a> JSValue<'a> for &'a [u8] {
    fn convert_to_rust(env: &'a JsEnv, js_value: napi_value) -> Result<Self, NjError> {
        // check if this is really buffer
        if !env.is_buffer(js_value)? {
            return Err(NjError::InvalidType(
                "Buffer".to_owned(),
                env.value_type_string(js_value)?.to_owned(),
            ));
        }

        let buffer = env.get_buffer_info(js_value)?;

        Ok(buffer)
    }
}