Either keep track of the offset in an `offset` variable and use that in all index accesses or create a slice of the buffer and work with the slice.
On Fri, Jul 27, 2012 at 10:10 PM, Yi Tan <[email protected]> wrote: > Thanks Tim > > I've checked https://github.com/pgriess/node-msgpack, but I'm afraid that's > not exact the thing I'm looking for. > > The problem I'm facing is: > > In our node app, we use socket to deal with large number of real-time binary > data sent from multiple clients. > > For performance and memory consideration, we left those message in buffer > and continuously read data segments > from the buffer to detect whether the app should process further segments in > the buff or stop and drop the buffer > if condition not met. > > Since the Buffer object is Nodejs is not resizable. So I just wonder why not > provide a postion property for the Buffer > object for streaming reading. > > Our current solution is a bit painful. To streamy read the buff, we inject > an position property into each Buff instance and > use a set of static helper method to process the buffer in order to push the > position going forward. > > For example, to continuously read a 32bit uint from the buf, we can not do > buf.readUInt32BE, we have to do BufHelper.readUInt32(buf) > > > Regards, > > ty > > > > 2012/7/27 Tim Caswell <[email protected]> >> >> If you're talking about a protocol parser, I find state machines work >> best. Do you need a streaming parser or one that first deframes >> messages and then parses pre-buffered messages? The techniques are >> similar but not quite the same. >> >> An example of a non-streaming binary parser would be my msgpack >> decoder or Felix's mysql protocol parser. >> >> Most streams have arbitrary chunk lengths that don't match up with >> message lengths. If you're using a pre-existing protocol (like mysql) >> then the framing is probably included in the wire protocol. >> >> On Thu, Jul 26, 2012 at 11:04 PM, Yi Tan <[email protected]> wrote: >> > Hi all, >> > >> > I'm working on a node project to process binary stream send/received via >> > socket connection. >> > >> > I'm new to Node, I found in the Buffer class, there is no property to >> > indicate current stream read position. And this cause a lot of difficult >> > when parsing complex binary stream. >> > >> > Could you give me some hint on how to implement a position property for >> > Buffer as well as to keep the best performance. >> > >> > Many thanks, >> > >> > ty >> > >> > -- >> > Job Board: http://jobs.nodejs.org/ >> > Posting guidelines: >> > https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines >> > You received this message because you are subscribed to the Google >> > Groups "nodejs" group. >> > To post to this group, send email to [email protected] >> > To unsubscribe from this group, send email to >> > [email protected] >> > For more options, visit this group at >> > http://groups.google.com/group/nodejs?hl=en?hl=en >> >> -- >> Job Board: http://jobs.nodejs.org/ >> Posting guidelines: >> https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines >> You received this message because you are subscribed to the Google >> Groups "nodejs" group. >> To post to this group, send email to [email protected] >> To unsubscribe from this group, send email to >> [email protected] >> For more options, visit this group at >> http://groups.google.com/group/nodejs?hl=en?hl=en > > > -- > Job Board: http://jobs.nodejs.org/ > Posting guidelines: > https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines > You received this message because you are subscribed to the Google > Groups "nodejs" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/nodejs?hl=en?hl=en -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
