string-fuzzy matching in C + +

Demand:

Access authorization profiles are sometimes configured in several dimensions, such as Company|product|sys configuration in this format:

1. Configuration "Sina|weibo|pusher" means that Sina company Weibo product Pusher system can access, and "Sina|weibo|sign" does not allow access

2. Configuration "Sina|*|pusher" means that the pusher system of all products of Sina Company can access

3. The configuration "*|*|pusher" means that all pusher systems of all products of the company are able to access

...

There are a lot of scenes like this, okay, simple things don't pull the eggs.

Realize:

In the face of this demand I think the first time is how to design the pattern string, how to quickly implement the function, because I now write a C service, so I first out of my mind is a lot of strchr (XXX, ' * '), STRCHR (xxx, ' | ') And so on, later found that this thing is not necessary to build their own wheels, there are ready-made functions can be used, that is fnmatch.

Google a bit, found that Fnmatch is not a lot of information, most of them are talking about PHP functions, so there is no way, can only write their own test.

#include <iostream> #include <fnmatch.h> #include <vector> using namespace std;  
    int main () {const char* ORGIN_STR = "Sina|weibo|pusher"; Char Pattern_arr[][20] = {{"Sina|*|pusher"}, {"sina|*|*"}, {"*|weibo|*"},//cannot be matched {"Sina|pic|*"}, {"*|*|sign"}, {"*|weibo|sign"}, {"*|pic|sign"}, {"Sina  
    |pic|sign "}, {" *|*|* "}};  
       
    static int pattern_arr_size = sizeof (Pattern_arr)/sizeof (pattern_arr[0));  
    Vector<char *> Vec_str;  
    for (int i = 0; i < pattern_arr_size i + +) {Vec_str.push_back (pattern_arr[i]);  
    int ret;  
    int z = 0; while (Z < 1) {for (int i = 0; i < vec_str.size (); i++) {ret = Fnmatch (vec_st  
            r.at (i), orgin_str, fnm_pathname); if (Fnm_nomatch = = ret) {cout<< ' Sorry I 'M failed ["<< vec_str.at (i) <<"] "<<endl;     
    }} ++z; }  
}

Results:

Experiment one, the results are not bad, fully meet the needs:

The requirements are met, and I'm worried about a problem, which is performance, commenting out the cout output, and then tuning the while Z statement to 1,000,000 and recompiling and running:

Time./fnmatch

Seems to be a good efficiency, 2.1s 100W time matching, the average 2us once, performance requirements are met ...

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