part of me wanted to call this module node-miyagi
.
please god let someone get the joke. preferably a girl. preferably gorgeous.
It blows my mind that these methods don't exist on the core node.js Buffer
object. srsly guise?
Install with npm.
npm install better-buffer
Constructor is compatible with existing Buffer
constructor, but also adds an
optional growSize
parameter. The only time that a BetterBuffer
will grow
is when you call the growToAccommodate()
method -- there's no auto-growing on
BetterBuffer::pushBack()
or Buffer::copy()
-- at least not yet.
Ensures that the buffer is at least big enough to store dataLengthToAccommodate
octets. The buffer will grow in intervals defind by its growSize
member, so
you may sometimes end up with a buffer that's slightly larger than necessary.
Queue-like functionality for buffers. Appends sourceBuffer
to the buffer at
the end of that buffer's actual data, as indicated by its dataLength
member. So
for example, if you have:
var myBuffer = new BetterBuffer(10, 5);
// myBuffer.length == 10
// myBuffer.dataLength == 0
...and you append, say, secondBuffer
, the length
of which is 6
:
myBuffer.pushBack(secondBuffer);
// myBuffer.length == 10
// myBuffer.dataLength == 6
myBuffer.dataLength
is now 6. Now let's append thirdBuffer
, the length of
which is 2
:
myBuffer.pushBack(thirdBuffer);
// myBuffer.length == 10
// myBuffer.dataLength == 8
myBuffer.dataLength
is now 8, and thirdBuffer
was written into myBuffer
starting at position 6.
In combination with BetterBuffer::popFront()
, this makes it much easier to
create queue- or stream-like behavior using simple buffer objects.
The buffer's dataLength
property is incremented accordingly.
Just a simple pop
function, like you'd find on a stack or queue. Hacks off the
first num
octets in the buffer, shifts everything in the buffer forward by the
same distance, and returns the popped octets in a new BetterBuffer
object.
The buffer's dataLength
property is decremented accordingly.
Creates a new BetterBuffer
containing an exact copy of the contents of the
buffer. NOTE: the returned buffer's size is equal to the source buffer's
dataLength
property, not its length
property.
For example, let's say you have a buffer myBuffer
of size 256
, and you've only
pushBack
ed one buffer of size 100
into it. This means that myBuffer.length
is 256
, but myBuffer.dataLength
is 100
. So when you call
cloneDataIntoNewBuffer
, it will return a buffer of size 100
, not 256
.
var myBuf = new BetterBuffer(10, 5);
myBuf.fill(0x00);
// myBuf.length == 10
// myBuf.dataLength == 0
// myBuf = <Buffer 00 00 00 00 00 00 00 00 00 00>
var smallerBuffer = new BetterBuffer(8);
smallerBuffer.fill(0xff);
// smallerBuffer.length == 8
// smallerBuffer.dataLength == 0
// smallerBuffer = <Buffer ff ff ff ff ff ff ff ff>
// now we explicitly set smallerBuffer.dataLength -- it's not necessary, but
// it makes things clearer conceptually
smallerBuffer.dataLength = smallerBuffer.length;
// what happens when we call growToAccommodate to ensure we have enough room?
myBuf.growToAccommodate(smallerBuffer.dataLength);
// smallerBuffer is smaller than myBuf, so myBuf.length is still 10
// go ahead and eat the smaller buffer
myBuf.pushBack(smallerBuffer);
// myBuf = <Buffer ff ff ff ff ff ff ff ff 00 00>
// myBuf.length == 10
// myBuf.dataLength == 8
var anotherBuffer = new BetterBuffer(8);
anotherBuffer.fill(0xaa);
// anotherBuffer.length == 8
// anotherBuffer.dataLength == 0
// anotherBuffer = <Buffer aa aa aa aa aa aa aa aa>
// again, we explicitly set anotherBuffer.dataLength for the sake of code readability
anotherBuffer.dataLength = anotherBuffer.length;
// let's try calling growToAccommodate again and see if anything happens this time
myBuf.growToAccommodate(myBuf.dataLength + anotherBuffer.dataLength);
// now, myBuf.length == 20 because:
// myBuf.dataLength == 8
// anotherBuffer.dataLength == 8
// and myBuf.growSize == 5 (myBuf's initial size was 10, and 10 + 5 + 5 == 20)
// now we can pushBack() safely
myBuf.pushBack(anotherBuffer);
// myBuf = <Buffer ff ff ff ff ff ff ff ff aa aa aa aa aa aa aa aa 00 00 00 00>
// myBuf.length == 20
// myBuf.dataLength == 16
// and just for good measure let's tack on a shitty example of popFront()
var justAPiece = myBuf.popFront(5);
// justAPiece = <Buffer ff ff ff ff ff>
// myBuf = <Buffer ff ff ff aa aa aa aa aa aa aa aa 00 00 00 00>
bryn austin bellomy < bryn@signals.io >
Copyright (c) 2012 bryn austin bellomy, signalenvelope / signals.io »
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.