RE: Efficient C++ XML validating parser?
Hi, If you decide to do without validation, then I've used TinyXML in a couple of projects, and am pretty happy with the footprint performance. http://www.grinninglizard.com/tinyxml/ Your right in that it will require you to write the parser manually, though, with all that that implies. Cheers, Rony -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Amos Shapira Sent: Wednesday, March 05, 2008 2:56 AM To: Israel Linux Mailing list Subject: Efficient C++ XML validating parser? Hello, Currently we use Xerces for C (http://xerces.apache.org/xerces-c/) to read XML files but are looking at making this as efficient as possible. The XML files are generated by our own software so some of us though that maybe we can get rid of validation of the input and go straight to event handling using SAX parsers. My concern with this approach is that it sounds like we'll end up with a hand-written parser for very specific version of the input schema, which will require us to keep the code in pace with changes in the schema. Instead, I was wondering what would be the best way to ask the XML parser to validate the input. Maybe some tool which converts an XML schema to tightly integrated C++ code would do the trick? I found http://tinyurl.com/2wqqp8 but it's just a research paper (NOT free), not open source code. What do people around here like to use for EFFICIENT XML parsing? Thanks, --Amos = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Efficient C++ XML validating parser?
On Wednesday 05 March 2008, Amos Shapira wrote: What do people around here like to use for EFFICIENT XML parsing? A stronger machine. Don't laugh... it may be much cheaper than developing and maintaining software. # = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Efficient C++ XML validating parser?
Two suggestions: There are GNU/GTK (depends on how you look at it) tools for handling XML, and one of the tools in the library is to validate (in code) XML... And sorry if it will sound like a troll's answer, but you can take the native XML implementation in FPC and write it binding to C++, and then use it with your application :) Ido On Wed, Mar 5, 2008 at 2:56 AM, Amos Shapira [EMAIL PROTECTED] wrote: Hello, Currently we use Xerces for C (http://xerces.apache.org/xerces-c/) to read XML files but are looking at making this as efficient as possible. The XML files are generated by our own software so some of us though that maybe we can get rid of validation of the input and go straight to event handling using SAX parsers. My concern with this approach is that it sounds like we'll end up with a hand-written parser for very specific version of the input schema, which will require us to keep the code in pace with changes in the schema. Instead, I was wondering what would be the best way to ask the XML parser to validate the input. Maybe some tool which converts an XML schema to tightly integrated C++ code would do the trick? I found http://tinyurl.com/2wqqp8 but it's just a research paper (NOT free), not open source code. What do people around here like to use for EFFICIENT XML parsing? Thanks, --Amos = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] -- http://ik.homelinux.org/ = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Efficient C++ XML validating parser?
Gilad Ben-Yossef wrote: Amos Shapira wrote: What do people around here like to use for EFFICIENT XML parsing? Isn't Efficient XML an oxymoron? Seriously, and despite the flame bait way I've introduced the subject, if you need to do XML parsing in a way which is more efficient then Xerces, maybe it is an indication that XML is a not a proper way to encode you r data. I'll bite. Without knowing Xerces too deeply, I think you can do MUCH faster than it, by feeding the schema before hand. Theoretically (though, the last time I said this word on this list an actual project came out [1]), you can write a parser that receives the schema, and produces yacc (or bison++) output for parsing it. That would, of course, make a compiler compiler compiler, but who's counting? You can then take the input file, and follow the usual procedures for generating C++, and then binary, from them. How about using a binary format which is compiled from XML ? In this day and age, is it really all that faster? What makes XML hard to parse, IMHO, is not the fact that it's text, it's the fact that it's hierarchal. You get all the benefits of using XML and no parsing overhead. Well, you lose one benefit - it's no longer in a standard parsable, nor even textual, format. Gilad Shachar = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Efficient C++ XML validating parser?
On Wed, 2008-03-05 at 12:43 +0200, Shachar Shemesh wrote: Gilad Ben-Yossef wrote: How about using a binary format which is compiled from XML ? In this day and age, is it really all that faster? What makes XML hard to parse, IMHO, is not the fact that it's text, it's the fact that it's hierarchal. You get all the benefits of using XML and no parsing overhead. Well, you lose one benefit - it's no longer in a standard parsable, nor even textual, format. Not necessarily. If you have a converter between XML and your binary format, and make it available everywhere your application is available, then the messages would still effectively be available in XML. You'll need also some way to force people to modify the converter whenever they modify the schema. Another way is to use one of the serializer/unserializer modules available in scripting languages such as Python or Perl. This will transform between your data structure's internal representation and a binary format. --- Omer -- May the holy trinity of $_, @_ and %_ be hallowed. My own blog is at http://www.zak.co.il/tddpirate/ My opinions, as expressed in this E-mail message, are mine alone. They do not represent the official policy of any organization with which I may be affiliated in any way. WARNING TO SPAMMERS: at http://www.zak.co.il/spamwarning.html = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
FSCK Error after upgrade Ubuntu 7.1
Hello List, Several days ago I asked Upgrade manager to install all available upgrades for my Kubuntu Desktop. (regular instalation, stock kernel 2.6.22-14-generic) disk partitions: 1 /boot 2 swap 3 / 4 Extended 5 /home It had finished successfully and required the reboot. After reboot I got blank screen filled with and so I used the SCD rescue to reinstall grub. Several strange things happened : 1. fsck on / runs only e2fsk although I know my / is ext3 2. when boot from Hard Disk, grub does not see /boot/vmlinuz (my boot partition is on thirst slice of HD), but it sees it as /vmlinuz The same with initrd 3. When grub finally boot the system fsck error on / and was thrown into maintanence shell: fsck 1.40.2 (12-Jul-2007) fsck.ext3: symbol lookup error: fsck.ext3: undefined symbol: et_ext2_error_table fsck.ext3: symbol lookup error: fsck.ext3: undefined symbol: et_ext2_error_table fsck died with exit status 127 Since / is mounted read-only I tried to boot from SCD and fix filesystem but SCD thinks it is ext2 and OK 4 . Although I did not fix a thing ( except changing /boot/vmlinuz to /vmlinuz in grub menu and canceling fsck check in fstab) my system continue boot after exiting from maintanence shell 5 . The system does not see / (/dev/sda3) as mounted anymore What goes wrong ?, why SCD rescue and Ubuntu disagree on / filesystem type and state ? Regards, Lev = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
[HAIFUX Lecture] Advanced Linux Kernel Networking - Neighboring Subsystem; IPSec by Rami Rosen
Next Monday, 10th of March, at 18:30 the Haifa Linux Club, will meet again and enjoy the lecture of Rami Rosen about Advanced Linux Kernel Networking - Neighboring Subsystem; IPSec abstract: * We will deal with arp table and arp cache, * Reachability and Network Unreachability Detection, * Reachability states (NUD_REACHABLE , NUD_NONE or NUD_FAILED, and more) * Garbage collection with the Neighboring Subsystem. * Interaction between Linux Kernel Routing Subsystem and Linux * Kernel Neighboring Subsystem. * IPsec - tunnels and encryption , xfrm API , IPsec flow cache. == We meet in Taub building, room 6. For instructions see: http://www.haifux.org/where.html Attendance is free, and you are all invited! == Future Lectures: How Ethernet works Nir Abulaffo24/3/2008 Advanced Linux Kernel Networking - third lecture Rami Rosen 7/4/2008 We are always interested in hearing your talks and ideas. If you wish to give a talk, hold a discussion, or just plan some event haifux might be interested in, please contact us at [EMAIL PROTECTED] -- Orr Dunkelman, [EMAIL PROTECTED] Any human thing supposed to be complete, must for that reason infallibly be faulty -- Herman Melville, Moby Dick. GPG fingerprint: C2D5 C6D6 9A24 9A95 C5B3 2023 6CAB 4A7C B73F D0AA (This key will never sign Emails, only other PGP keys. The key corresponds to [EMAIL PROTECTED]) = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Next Perl-IL Meeting - Sunday, 16-March-2008
The Israeli Perl Mongers ( http://www.perl.org.il/ ) are going to have their first meeting for 2008 on Sunday, 16-March-2008. The place will be the Schreiber MathCS building, room 008 (entrance floor), Tel Aviv University. More information on how to get there can be found here: http://www.cs.tau.ac.il/telux/ The meeeting will start at 18:30. The tentative schedule is: 1. Ran Eilam - Config::* - the Alenby St. of CPAN. (30 minutes) 2. Fallback talk if there are no other talks: Shlomi Fish - http://www.shlomifish.org/lecture/Perl/Lightning/Too-Many-Ways/ . (15-30 minutes) - Some more talks are being negotiated and we will be happy to host your talk on a subject you find interesting. Sharpen your perls and mark your calendars because a new season of Perl meetings is about to start. Regards, Shlomi Fish - Shlomi Fish [EMAIL PROTECTED] Homepage:http://www.shlomifish.org/ I'm not an actor - I just play one on T.V. = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Efficient C++ XML validating parser?
On Wed, Mar 5, 2008 at 9:43 PM, Shachar Shemesh [EMAIL PROTECTED] wrote: Gilad Ben-Yossef wrote: Amos Shapira wrote: What do people around here like to use for EFFICIENT XML parsing? Isn't Efficient XML an oxymoron? Seriously, and despite the flame bait way I've introduced the subject, if you need to do XML parsing in a way which is more efficient then Xerces, maybe it is an indication that XML is a not a proper way to encode you r data. I'll bite. Thanks to everyone for your answers. I'm replying to Shachar's reply because his is the closest to what I have to add to this, plus some more info about my question as I learned since I sent it. Without knowing Xerces too deeply, I think you can do MUCH faster than it, by feeding the schema before hand. Theoretically (though, the last Xerces is apparently the Lincoln of XML parsers i.e. it supports everything there is to support in the standard but it comes with a huge weight attached to it. On my desktop it's the 9th largest library at almost 4Mb, comes just before libkhtml and twice the size of libc. But library size is not all I can say against it - it adheres to the standard approach of DOM (tons of object, lots of memory) or SAX (i.e. have to manually handle each event in the code which uses SAX). There are a few newer approaches to parse XML files, there is a pretty good list at http://en.wikipedia.org/wiki/Xml_parser#Processing_XML_files The one that appeals the most to me is Data Binding (http://en.wikipedia.org/wiki/Xml_parser#Data_binding), i.e., as Shachar describes below - it's based on a program which reads the schema and builds code (in my case, C++ class) which reads files of this specific schema, its objects are strongly-typed in-memory representations of the data in the XML file and provide convenient accessors. Presumebly, because these classes are schema-specific, they can cut a lot of checks for irrelevant execution paths. If you ever wrote XDR/RPC stuff (I'm talking about the stuff the NFS and friends uses for network-level representation) then it might be something similar - it used to have a program to convert language independent data representation to various language-specific implementations of classes to marshal and demarshal data (only I forgot the name of the XDR compiler right now). The snag about Data Binding is that all the implementations I found so far are either for Java or Proprietary and cost a fortune (thousands of dollars per developer seat, where you have to buy a license for every developer who links his code with the output of the programs). Ah - and our final programs (the ones we ship to customers) have to support all sorts of UNIX variants, and Windows, not just Linux. The only one which keeps our hopes alive is xmlbeanscxx (http://xmlbeansxx.touk.pl/). I'm struggling with getting it to compile and run for now. Another one is CodeSynthesis XSD (http://www.codesynthesis.com/products/xsd/), it's GPL so we we can't link it with our proprietary code. Here is a pretty complete list of XML Data Binding resources, almost all options for C/C++ are commercial: http://www.rpbourret.com/xml/XMLDataBinding.htm Thanks again for everyone's input. --Amos = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
To maintainers of Israeli open source web sites
Hi All, It just took me quite a while to find current archives of linux-il on the net in order to point to an article there. I finally found a good archive at mail-archive (http://www.mail-archive.com/linux-il@cs.huji.ac.il/). I know this question sometimes returns to haunt the list but not being able to find the archives causes a sort of a chicken-and-egg problem, doesn't it? :) So please - if you maintain a web site which mentions Linux-IL please add a pointer to its archives (mail-archive looks good) to your web site so Google can find it more easily. Web sites I looked through include linux.org.il, hamakor.org.il (which has a non-current archive) and http://linuxil.objectis.net/, iglu.org.il, whatsup, linmagazine Thanks, --Amos = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: To maintainers of Israeli open source web sites
On 06/03/2008, Amos Shapira [EMAIL PROTECTED] wrote: Hi All, It just took me quite a while to find current archives of linux-il on the net in order to point to an article there. I finally found a good archive at mail-archive (http://www.mail-archive.com/linux-il@cs.huji.ac.il/). I know this question sometimes returns to haunt the list but not being able to find the archives causes a sort of a chicken-and-egg problem, doesn't it? :) So please - if you maintain a web site which mentions Linux-IL please add a pointer to its archives (mail-archive looks good) to your web site so Google can find it more easily. Web sites I looked through include linux.org.il, hamakor.org.il (which has a non-current archive) and http://linuxil.objectis.net/, iglu.org.il, whatsup, linmagazine Thanks, --Amos I will do that this evening. Are there any other high-value sites that maybe we should be promoting? Of course I'd love to add my own gibberish.co.il (shameless plug) but if someone wants to publish their list of important Hebrew or Israeli Linux websites I will pick a few and link to them as well. Dotan Cohen http://what-is-what.com http://gibberish.co.il א-ב-ג-ד-ה-ו-ז-ח-ט-י-ך-כ-ל-ם-מ-ן-נ-ס-ע-ף-פ-ץ-צ-ק-ר-ש-ת A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing?
OpenOffice in educational institutes in Israel?
This might interest a few people here: http://it.themarker.com/tmit/article/2992 Could it *be it*, finally? There have been such plays in the past, usually to attract attention and get lower prices from M$. Seems like it is a real first step, and a considerable one(?). If so, its a nice way to start the morning :-) Boaz. = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
