Change the comment character in Boost Program Options? - php

I have an app that has components in both PHP and C++. They need to share some configuration options, and I'd like to use one file to share these -- a simple config file.
Fortunately, PHP has parse_ini_file() and Boost has Program Options and they share virtually identical semantics. They can both can read all the options I need.
The one "gotcha" here is that PHP's function supports semicolon (";") as the comment character, and Boost supports hash ("#"). PHP used to support hash, but now it throws a deprecated error on it.
I'm pretty sure I can't easily change the comment character in PHP. Anyone know if I can change the Boost comment character? I'd love to not have to rewrite all this functionality just for comments.

Figured out a solution to this problem.
Given that Boost is reasonably robust, I couldn't see a reasonable way to replace the comment character, and the # is a fairly accepted comment character in config files, I solved it in PHP.
I load the config file using file_get_contents, use a preg_replace to remove the lines that begin with #, then pass the result through parse_ini_string.

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Does a reliable way to capitalize Unicode text exist?

I recently had to deal with some complex problems working with Unicode string (using PHP, a language I know pretty well). The mbstring extension was not really working properly and we had huge pains trying to capitalize Unicode letters, which with ASCII text is a trivial problem, already solved in a variety of ways.
If I had to solve this problem with ASCII text, I would probably just take the character, check if it is a letter and then subtract 32 from its ASCII value, for example! But as for now, I could not find anything explaining how the problem of capitalization of Unicode text has been solved: do I need to store a complete associative table to map every lowercase character to its related uppercase version? I suppose (and hope) I will hear a huge NO!
The heart of the question: does any method to correctly convert lowercases into uppercases (and back) exist when operating with Unicode characters? And if this is the case, which strategies are applied?
For this test suppose you do not have any, but really ANY module available: no mbstring, no iconv, nothing. Moreover, for the sake of simplicity suppose to have the problem of recognizing individual characters already solved, our String object has a nextChar() method which can be used to find the next character, independently from its byte-length. Suppose that what you want to do is taking a string, iterate over it with nextChar() and, for each character, capitalize it if possible.
If unclear or in the need of more information simply comment, I will try to answer your doubts, if they are not even bigger than mine at the moment ;)
You can try PortableUTF8 library, written as alternative to mbstring and iconv.
http://pageconfig.com/post/portable-utf8
Another interesting library is Stringy. It works by default with mbstring but if module is not located it will use polyfill package .
https://github.com/danielstjules/Stringy
In order to improve knowledge of the problem it's interesting to read:
What factors make PHP Unicode-incompatible?
I hope it will be useful for you.

How to remove question mark garbage data, dynamically, from files?

I have an unknown number of files with garbage data interspersed and I want to remove said garbage data dynamically, perhaps using regex.
It'll usually look something like this in an HTML file in a browser:
this is the beginning of the file, ��
In the file, it'll appear as like this:
this is the beginning of the file, xE2xA0
I tried using a regex editor to remove it, but it was to no avail, it cannot find it at all. How can I remove this garbage data? Again, some of the files have all kinds of HTML markup.
Thank you for any help.
Those appear because something is wrong with a character set on your site.
For example, your files are stored in Unicode, but your Content-Type is set as text/html; charset=ISO-8859-1. The problem could also be how text is stored in your database, or with how text is represented internally by your programming language.
Rather than try to strip them out, it is better to get the character set correct. This is generally a frustrating process because there are so many points where the problem could have been introduced.
You don't say what technologies you use. Generally you can search for how to solve character set issues with specific technologies such as "character set problems mysql" to find solutions.
I recommend using command line tools like file to examine what character set a text file is stored in and iconv to convert text files from one character set to another.
There are two possibilities. The first, unlikely, one is that you are getting 0xe2 0xa0 ... because there are Braille patterns in the document.
As for the second possibility, 0xa0 is NBSP. 0xe2 makes me think of ISO-8859-5.
Is there any chance someone copied & pasted stuff from a Russian version of some software package?
Also, you can get & use iconv on Windows.

PHP string functions vs mbstring functions

I have an application that has so far been in English only. Content encoding throughout templates and database has been UTF-8. I am now looking to internationalize/translate the application into languages that have character sets absolutely needing UTF-8.
The application uses various PHP string functions such as strlen(), strpos(), substr(), etc, and my understanding is that I should switch these for multi-byte string functions such as mb_strlen(), mb_strlen(), mb_substr(), etc, in order for multi-byte characters to be handled correctly. I've tried to read around this topic a little but virtually everything I can find goes deep into "encoding theory" and doesn't provide a simple answer to the question: If I'm using UTF-8 throughout, can I switch from using strlen() to mb_strlen() and expect things to work normally in for example both English and Arabic, or is there something else I still need to look out for?
Any insight would be welcome, and apologies if I'm offending someone who has encoding close to their heart with my relative ignorance.
No. Since bytearrays are also strings in PHP, a simple replacement of the 8-bit string functions with their mb_* counterparts will cause nothing but trouble. Functions like strlen() and substr() are probably more frequently used with bytes than actual text strings.
At the place I last worked, we managed to build a multilingual web-site (Arabic, Hindi, among other languages) in PHP without using the mbstring library at all. Text string manipulation actually doesn't happen that often. When it does, it would require far more care than just changing a function name. Most of the challenges, I've found, lie on the HTML side. Getting a page layout to work with a RTL language is the non-trivial part.
I don't know if you're just using Arabic as an example. The difficulty of internationalization can vary quite substantially depending on whether "international" means European languages only (plus Russian), or if it's inclusive of Middle-Eastern, South-Asian, and Far-East languages.
Check the status of the mbstring.func_overload flag in php.ini
If (ini_get('mbstring.func_overload') & 2) then functions like strlen() (as listed here) are already overloaded by the mb_strlen() function, so there is no need for you to call the mb_* functions explicitly.
The number of multibyte functions really needed are under 10, so create 3 or 5 questions whether the usage of the function or logic is good. This quesiton is obsecure and hard to answer. Small questions can get quick answers. Concrete questions can bring out good answers. let me know when you create other questions.
If you need use cases, see the fallback functions in CMSes such as Wordpress, MediaWiki, Drupal.
When you decide to start using mbstring, You should avoid using mbstring.func_overload directive. Mbstring maintainers are going to deprecate mbstring.func_overload in PHP 5.5 or 5.6 (see PHP core mailing list in 2012 April). mbstring.func_overload breaks the codebases that are not expected to use mbstring.func_overload. you can see the cases in CakePHP, Zend Framework 1x in caliculating Content-Length by using strlen().
I answerd the similar question in another place: Should i refactor all my framework to use mbstring functions?

how to check if a php file is obfuscated?

is there any way we can check if a php file has been obfuscated, using php? I was thinking regex maybe (for instance ioncube's encoded file contains a very long alphabet string, etc.
One idea is to check for whitespace. The first thing that an obfuscator will do is to remove extra whitespace. Another thing you can look for is the number of characters per line, as obfuscators will put all the code into few (one?) lines.
Often, obsfuscators initialize very large arrays to translate variables into less meaningful names (eg. see obsfucator article
One technique may be to search for these super-large arrays, close to the top of the class/file etc. You may be able to hook xdebug up to examine/look for these. The whole thing of course depends on the obsfuscation technique used. Check the source code, there may be patterns they've used that you can search on.
I think you can use token_get_all() to parse the file - then compute some statistics. For example check for number of function calls(in calse obfuscator uses some eval() string and nothing else) and calculate average function length - for obfuscators it will usually be about 3-5 chars, for normal PHP code it should be much bigger. You can also use dictionary lookup for function/variable names, check for comments etc. I think if you know all obfuscator formats that you want to detect - it will be easy.

How do I create a regular expression that disallows symbols?

I got a question regarding regexp in general. I'm currently building a register form where you can enter the full name (given name and family name) however I cant use [a-zA-Z] as a validation check because that would exclude everyone with a "foreign" character.
What is the best way to make sure that they don't enter a symbol, in both php and javascript?
Thanks in advance!
The correct solution to this problem (in general) is POSIX character classes. In particular, you should be able to use [:alpha:] (or [:alphanum:]) to do this.
Though why do you want to prevent users from entering their name exactly as they type it? Are you sure you're in a position to tell them exactly what characters are allowed to be in their names?
You first need to conceptually distinguish between a "foreign" character and a "symbol." You may need to clarify here.
Accounting for other languages means accounting for other code pages and that is really beyond the scope of a simple regexp. It can be done, but on a higher level, the codepages have to work.
If you strictly wanted your regexp to fail on punctuation and symbols, you could use [^[:punct:]], but I'm not sure how the [:punct:] POSIX class reacts to some of the weird unicode symbols. This would of course stop some one from putting in "John Smythe-Jones" as their name though (as '-' is a punctuation character), so I would probably advise against using it.
I don’t think that’s a good idea. See How to check real names and surnames - PHP
I don't know how you would account for what is valid or not, and depending on your global reach, you will probably not be able to remove anything without locking out somebody. But a Google search turned this up which may be helpful.
http://nadeausoftware.com/articles/2007/09/php_tip_how_strip_symbol_characters_web_page
You could loop through the input string and use the String.charCodeAt() function to get the integer character code for each character. Set yourself up with a range of acceptable characters and do your comparison.
As noted POSIX character classes are likely the best bet. But the details of their support (and alternatives) vary very much with the details of the specific regex variant.
PHP apparently does support them, but JavaScript does not.
This means for JavaScript you will need to use character ranges: /[\u0400-\u04FF]/ matches any one Cyrillic character. Clearly this will take some writing, but not the XML 1.0 Recommendation (from W3C) includes a listing of a lot of ranges, albeit a few years old now.
One approach might be to have a limited check on the client in JavaScript, and the full check only server side.

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