沈阳专业做网站方案,网站的友情连接怎么做,上上上海网站设计,唐山网站快速排名提升由于C语言的正则表达式API相对比较简易.默认API只有regcomp/regerror/regexec/regfree这些函数.相对于其他的高级语言中正则表达式所所能实现的功能(如:查找/替换)有所欠缺.所以想着自己写下一些需要的函数以备后续需要使用.
#ifndef _E_REGEX_INCLUDE
#define _E_REGEX_INCLU…由于C语言的正则表达式API相对比较简易.默认API只有regcomp/regerror/regexec/regfree这些函数.相对于其他的高级语言中正则表达式所所能实现的功能(如:查找/替换)有所欠缺.所以想着自己写下一些需要的函数以备后续需要使用.
#ifndef _E_REGEX_INCLUDE
#define _E_REGEX_INCLUDE
#include regex.h
#include string.h
#include stdlib.h
#include stdio.h
#include stdbool.htypedef int errno_t;static size_t position 0;//functions prototype
char* regnext(regex_t* regex,char* content);
void _r_release(void);
bool regreplace(regex_t* regex,char** content,char* replacement);
void regreplaceAll(regex_t* regex,char** content,char* replacement);int main(void){char* content (char*)sjdlf12323ldjslfjsjf133334;char* pattern (char*)([[:digit:]][[:digit:]])\\1;regex_t regex;errno_t state regcomp(regex,pattern,REG_EXTENDED);if(state){char* errbuf calloc(20,sizeof(char));regerror(state,regex,errbuf,20);fprintf(stderr,Regex:%s compile failed.\nReason: %s\n,pattern,errbuf);free(errbuf);regfree(regex);exit(EXIT_FAILURE);}printf(content: %s\n,content);char* replacement (char*);regreplaceAll(regex,content,replacement);printf(content: %s\n,content);regfree(regex);
}//find next match
char* regnext(regex_t* regex,char* content){regmatch_t matches[regex-re_nsub 1];errno_t state regexec(regex,content,regex-re_nsub 1,matches,0);if(state REG_NOMATCH){_r_release();return NULL;}char* reval (char*)calloc(matches[0].rm_eo - matches[0].rm_so 1,sizeof(char));memcpy(reval,content position matches[0].rm_so,matches[0].rm_eo - matches[0].rm_so);position matches[0].rm_eo;return reval;
}//replace first
bool regreplace(regex_t* regex,char** content,char* replacement){regmatch_t matches[regex-re_nsub 1];errno_t state regexec(regex,*content,regex-re_nsub 1,matches,0);if(state REG_NOMATCH){return false;}char* newContent (char*)calloc(strlen(*content) strlen(replacement) - (matches[0].rm_eo - matches[0].rm_so),sizeof(char));size_t head matches[0].rm_so;size_t middle strlen(replacement);size_t end strlen(*content) - matches[0].rm_eo;memcpy(newContent,*content,head);memcpy(newContent head,replacement,middle);memcpy(newContent head middle,*content matches[0].rm_eo,end);*content newContent;return true;
}//replace all
void regreplaceAll(regex_t* regex,char** content,char* replacement){for(;regreplace(regex,content,replacement););
}void _r_release(void){position 0;
}#endif
