使用boost Spririt解析文本文件,二进制包 [英] Parsing text file with binary envelope using boost Spririt
问题描述
目前,我正在尝试写一个由小信封,校验包围ASCII文本文件解析器。
该文件的基本结构是:< 0X02><文件有效载荷><×03>< 16位CRC>
和我想提取有效载荷在另一个字符串给它喂
下一个解析器。
我用解析这个包分析器前pression是:
齐:: phrase_parse(
第一个,最后,
烧焦_('\\ X02')>> *打印>>烧焦_('\\ X02')>> * xdigit,
空间
);
输入消耗......我已经尝试过倾倒了有效载荷:
齐:: phrase_parse(
第一个,最后,
烧焦_('\\ X02')>> *打印[COUT<< _1>>烧焦_('\\ X02')>> * xdigit,
空间
);
但问题是,省略每换行,空白等!
现在我的问题:
-
我如何提取0X02 /×03(ETX / STX)字节之间的内容
不正确忽略空格,换行等。 -
和是我的方法先取出信封,然后解析
有效载荷好或有另一种更好的方法,我应该使用?
使用例如齐::谋求/气:: confix让你开始(库的<一个部分都href=\"http://www.boost.org/doc/libs/1_57_0/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/confix.html\" rel=\"nofollow\">http://www.boost.org/doc/libs/1_57_0/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/confix.html).
但问题是,省略每换行,空白等!
块引用>嗯,这是<一个href=\"http://stackoverflow.com/questions/17072987/boost-spirit-skipper-issues/17073965#17073965\">what一个船长确实。不要使用,或者:
使用
补气生:: []
要提取文本介入,我建议使用
补气生::
。虽然我不知道你其实想将它复制到一个字符串(复制听起来昂贵)。当源是一个流(或输入迭代器的其他来源),你能做到这一点可能。精囊炎的规则:
MyRule的='\\ X02'&GT;原料[*(char_ - '\\ X03')]≥ '\\ X03';
您可以添加校验:
MyRule的='\\ X02'&GT;原料[*(char_ - '\\ X03')] [_a = _checksum(_1)]≥ '\\ X03'&GT;&GT;齐::字(_a);
假设
齐::当地人&LT; uint16_t&GT;
_checksum
是一个合适的凤凰仿函数,它接受一个对源迭代器返回的uint16_t
当然,你可能preFER保持校验解析器之外。
I'm currently trying to write a parser for an ASCII text file that is surrounded by a small envelope with checksum.
The basic structure of the file is: <0x02><"File payload"><0x03><16bit CRC>
and I want to extract the payload in another string to feed it to the next parser.
The parser expression I use to parse this envelope is:
qi::phrase_parse( first, last, char_('\x02') >> *print >> char_('\x02') >> *xdigit, space );
The input is consumed... and I already tried to dump out the payload:
qi::phrase_parse( first, last, char_('\x02') >> *print[cout << _1] >> char_('\x02') >> *xdigit, space );
But problem is that every newline, blank etc. is omitted!
Now my questions:
How do I extract the content between the 0x02/0x03 (ETX/STX) bytes correctly without omitting spaces, newlines etc.
And is my approach to first remove the envelope and then parse the payload good or is there another better approach I should use?
解决方案Use e.g. qi::seek/qi::confix to get you started (both part of the repository http://www.boost.org/doc/libs/1_57_0/libs/spirit/repository/doc/html/spirit_repository/qi_components/directives/confix.html).
But problem is that every newline, blank etc. is omitted!
Well, that's what a skipper does. Don't use one, or:
Use
qi::raw[]
To extract the intervening text, I suggest using
qi::raw
. Although I'm not sure you actually want to copy it to a string (copying sounds expensive). You could do this probably when the source is a stream (or other source of input iterators).Seminal rule:
myrule = '\x02' > raw [ *(char_ - '\x03') ] > '\x03';
You could add the checksumming:
myrule = '\x02' > raw [ *(char_ - '\x03') ] [ _a = _checksum(_1) ] > '\x03' >> qi::word(_a);
Assuming
qi::locals<uint16_t>
_checksum
is a suitable Phoenix functor that takes a pair of source iterators and returnsuint16_t
Of course you might prefer to keep checksumming outside the parser.
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