48 lines
1.5 KiB
Markdown
48 lines
1.5 KiB
Markdown
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BufferCursor
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============
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This is a simple module that allows you to traverse a Buffer iteratively. You
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can read and write different types and the cursor's position will update with
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the proper size, which you can see through `.tell()` you can also
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`.seek()`
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```javascript
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var bc = new BufferCursor(buffer);
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bc.readUInt16BE();
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bc.readUInt8();
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bc.readUInt32BE();
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console.log(bc.tell());
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```
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Will output `7`
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Methods
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-------
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For the most part `BufferCursor` and `Buffer` share the same methods, there's
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just a slight alteration in method signature, none of the methods take an
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offset.
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So `.readUInt16LE(10)` in `Buffer` is equivalent to `bs.seek(10); bs.readUInt16LE();`
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All `read[U]Int` and `write[U]Int` methods are reproduced, as are `toString`,
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`write`, `fill`, and `slice`. All of these methods will move the cursor through
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the stream and do not take an offset parameter, where an `end` parameter would
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normaly be used, here you supply a `length`.
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The following are additional methods:
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* `seek(value)` -- Seek to an arbitrary position in the stream
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* `tell()` -- Return the current location in the stream
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* `eof()` -- Return true if at the end of the stream
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* `toByteArray([method])` -- This is a special helper method which will return
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the *entire* stream (i.e. from the start) as an array of numbers.
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- By default it will use `readUInt8` but you can pass in any
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`read[U]Int[8,16,32][LE,BE]` to change what the array is made of
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Properties
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----------
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* `.buffer` -- Access to the raw buffer
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* `.length` -- The size of the buffer
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