| 14 |
liveuser |
1 |
## Buffers
|
|
|
2 |
|
|
|
3 |
NAN's `node::Buffer` helpers exist as the API has changed across supported Node versions. Use these methods to ensure compatibility.
|
|
|
4 |
|
|
|
5 |
- <a href="#api_nan_new_buffer"><b><code>Nan::NewBuffer()</code></b></a>
|
|
|
6 |
- <a href="#api_nan_copy_buffer"><b><code>Nan::CopyBuffer()</code></b></a>
|
|
|
7 |
- <a href="#api_nan_free_callback"><b><code>Nan::FreeCallback()</code></b></a>
|
|
|
8 |
|
|
|
9 |
<a name="api_nan_new_buffer"></a>
|
|
|
10 |
### Nan::NewBuffer()
|
|
|
11 |
|
|
|
12 |
Allocate a new `node::Buffer` object with the specified size and optional data. Calls `node::Buffer::New()`.
|
|
|
13 |
|
|
|
14 |
Note that when creating a `Buffer` using `Nan::NewBuffer()` and an existing `char*`, it is assumed that the ownership of the pointer is being transferred to the new `Buffer` for management.
|
|
|
15 |
When a `node::Buffer` instance is garbage collected and a `FreeCallback` has not been specified, `data` will be disposed of via a call to `free()`.
|
|
|
16 |
You _must not_ free the memory space manually once you have created a `Buffer` in this way.
|
|
|
17 |
|
|
|
18 |
Signature:
|
|
|
19 |
|
|
|
20 |
```c++
|
|
|
21 |
Nan::MaybeLocal<v8::Object> Nan::NewBuffer(uint32_t size)
|
|
|
22 |
Nan::MaybeLocal<v8::Object> Nan::NewBuffer(char* data, uint32_t size)
|
|
|
23 |
Nan::MaybeLocal<v8::Object> Nan::NewBuffer(char *data,
|
|
|
24 |
size_t length,
|
|
|
25 |
Nan::FreeCallback callback,
|
|
|
26 |
void *hint)
|
|
|
27 |
```
|
|
|
28 |
|
|
|
29 |
|
|
|
30 |
<a name="api_nan_copy_buffer"></a>
|
|
|
31 |
### Nan::CopyBuffer()
|
|
|
32 |
|
|
|
33 |
Similar to [`Nan::NewBuffer()`](#api_nan_new_buffer) except that an implicit memcpy will occur within Node. Calls `node::Buffer::Copy()`.
|
|
|
34 |
|
|
|
35 |
Management of the `char*` is left to the user, you should manually free the memory space if necessary as the new `Buffer` will have its own copy.
|
|
|
36 |
|
|
|
37 |
Signature:
|
|
|
38 |
|
|
|
39 |
```c++
|
|
|
40 |
Nan::MaybeLocal<v8::Object> Nan::CopyBuffer(const char *data, uint32_t size)
|
|
|
41 |
```
|
|
|
42 |
|
|
|
43 |
|
|
|
44 |
<a name="api_nan_free_callback"></a>
|
|
|
45 |
### Nan::FreeCallback()
|
|
|
46 |
|
|
|
47 |
A free callback that can be provided to [`Nan::NewBuffer()`](#api_nan_new_buffer).
|
|
|
48 |
The supplied callback will be invoked when the `Buffer` undergoes garbage collection.
|
|
|
49 |
|
|
|
50 |
Signature:
|
|
|
51 |
|
|
|
52 |
```c++
|
|
|
53 |
typedef void (*FreeCallback)(char *data, void *hint);
|
|
|
54 |
```
|