On Wed, Dec 19, 2012 at 5:18 AM, Gustavo Sverzut Barbieri < barbi...@profusion.mobi> wrote:
> On Wednesday, December 19, 2012, thomasg wrote: > > > On Wed, Dec 19, 2012 at 4:38 AM, Gustavo Sverzut Barbieri < > > barbi...@profusion.mobi <javascript:;>> wrote: > > > > > Hi Thomas, > > > > > > The standard way is pretty fast and lean, but it is a SAX-like parser. > > That > > > mean you only get tokens, for the tags you need to call yet another > > > function to split the tag and arguments. > > > > > > It is good enough to parse svg, as done by Esvg. Should be also enough > to > > > parse config files and your chat.xml > > > > > > There is also a version trust creates nodes from XML. It's useful to > > debug > > > and for simple cases without performance worries. As very likely you > will > > > store your parsed data in a custom structure than a generic "Dom", I > > > recommend using the sax version. > > > > > > I didn't try the example with your XML, but seems to be okay. The > example > > > could use eina_strbuf instead of array of strings, but that's marginal. > > > Also could use the size and avoid strncmp(), but also marginal for an > > > example. > > > > > > What is exactly failing? > > > > > > > As you can see, the tags are totally wrong. > > They are neither corretly aligned (a <foo> can be closed with </bar> and > > not just </foo>), nor do the items correspond with the tags. > > So if the input is not 100% like the parser expects it, say there's an > > additional level, the parser won't fail but just receive totally wrong > > data. > > If I want to make sure that I get the date from tag <baz>DATA</baz>, I > have > > to manually compare the string and it seems that I might as well just > parse > > it myself alltogether. > > > That is always the case with sax. It allows you to handle errors yourself, > like abort, auto fix, etc. like parsing bogus HTML that is common in the > Internet. > > I don't recall how strict I was with the tree/node version, I guess to make > it usable by Evas textblock u can close tags with </>, but not sure if you > specify an incorrect close tag what it would do. Anyway I'd recommend a > final version to avoid the intermediate node tree and use sax directly, > then you get more eficient data structures. > > Also consider always using the size. The original buffer is not modified, > then strings will not be null terminated. > > Usually the sax parser will keep a stack, and you can validate based in > that. But just validate if data is untrusted. Same for attributes, you just > pay the price if you expect them for such tag. IOW it can be very > efficient. > > The added benefit of using it over manual parse is that it will handle > whitespaces and also do minimal tag boundary match. If > is missing, etc. > that will emit errors. > > Hm, I guess I had/have some misconceptions on how a SAX parser was supposed to work. It just seemed like a terrible idea to just take the data as it comes while ignoring half of it. Then again, to me XML seems like a terrible idea in general :) Thanks for clearing it up. > > > > > > > > > > > On Wednesday, December 19, 2012, thomasg wrote: > > > > > > > Hi everyone, > > > > > > > > I was just looking at Eina Simple XML which, at first sight seemed a > > nice > > > > tiny XML library. > > > > However after looking closer, it seems that it is only useful to > create > > > > basic XML files, but NOT to read/parse them. > > > > > > > > I used the eina_simple_xml_parse function and realized, that this > > > basically > > > > is it, every single step of parsing has to be done manually and it > > > > basically makes no difference if eina_simple_xml is used or not at > all. > > > > I then took a look at the example parser in > eina_simple_xml_parser_01.c > > > and > > > > realized that, for the same reason, this is a extremely poor parser, > > > > basically worthless (no offense intended). > > > > Actually it is so poor, it is not even a simple XML parser because > all > > it > > > > does is check if the input looks somewhat similar to XML. > > > > > > > > I realize, that this is not meant to be a full featured parser or > even > > a > > > > basic parser, but seeing as it is hardly a parser at all, I can't see > > the > > > > point of having it (as an example). > > > > > > > > On the other hand, simple xml does have the concept of nodes using > eina > > > > inlists and such, but they seem to be usable only for creating xml, > not > > > > reading it. > > > > > > > > So my question is: Am I missing something here? > > > > > > > > Here's a modified/broken chat.xml file to be parsed by the example > code > > > to > > > > show how poorly it does: http://bpaste.net/show/65296/ > > > > If there's no better way to do it, I'd suggest to make this explicit > in > > > the > > > > docs/examples and/or remove the example. > > > > > > > > Regards > > > > > > > > -- > > > > thomasg > > > > > > > > ------------------------------------------------------------------------------ > > LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial > > Remotely access PCs and mobile devices and provide instant support > > Improve your efficiency, and focus on delivering more value-add services > > Discover what IT Professionals Know. Rescue delivers > > http://p.sf.net/sfu/logmein_12329d2d > > _______________________________________________ > > enlightenment-devel mailing list > > enlightenment-devel@lists.sourceforge.net <javascript:;> > > https://lists.sourceforge.net/lists/listinfo/enlightenment-devel > > > > > -- > Gustavo Sverzut Barbieri > http://profusion.mobi embedded systems > -------------------------------------- > MSN: barbi...@gmail.com > Skype: gsbarbieri > Mobile: +55 (19) 9225-2202 > > ------------------------------------------------------------------------------ > LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial > Remotely access PCs and mobile devices and provide instant support > Improve your efficiency, and focus on delivering more value-add services > Discover what IT Professionals Know. Rescue delivers > http://p.sf.net/sfu/logmein_12329d2d > _______________________________________________ > enlightenment-devel mailing list > enlightenment-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/enlightenment-devel > ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. 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