Mercurial > hg > Applications > Grep
view c/regexParser/createRegexTree.cc @ 88:7809fb223dc9
fix Makefile
author | masa |
---|---|
date | Fri, 23 Oct 2015 15:38:49 +0900 |
parents | aef2546cd130 |
children | 50a146c05192 |
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#include <stdlib.h> #include "regexParser.h" NodePtr createNode(unsigned char,NodePtr,NodePtr); NodePtr charClass(RegexInfoPtr); NodePtr group(RegexInfoPtr); void token(RegexInfoPtr); NodePtr regexAtom(RegexInfoPtr); NodePtr regex(RegexInfoPtr); /** * Create a node of regex parse tree. * tokenType * regexPosition(state) * stateTransitionTable */ NodePtr createNode(unsigned char character, NodePtr left, NodePtr right) { NodePtr n = (NodePtr)malloc(sizeof(Node)); n->self = n; n->Value.character = character; n->left = left; n->right = right; return n; } // <charClass> ::= '['<literal>'-'<literal>']' NodePtr charClass(RegexInfoPtr ri) { NodePtr n = (NodePtr)malloc(sizeof(Node)); unsigned char startChar = ri->ptr[0]; while (ri->ptr[0] == '-') { ri->ptr++; } unsigned char endChar = ri->ptr[0]; unsigned char *charTable = (unsigned char*)malloc(sizeof(char)*256); return n; } // <literal> ::= [a-z][A-Z][0-9] NodePtr literal(RegexInfoPtr ri) { unsigned char *top = ri->ptr; NodePtr n = createNode(ri->ptr[0],0,0); ri->ptr++; return n; } // <group> ::= '('<regex>')' NodePtr group(RegexInfoPtr ri) { return regex(ri); } void token(RegexInfoPtr ri) { while (ri->ptr[0] != '\0') { if (ri->ptr[0] == '('){ ri->ptr++; ri->tokenType = '('; ri->tokenValue = 0; if (ri->ptr[1] == ')') { ri->ptr++; } return; } else if (ri->ptr[0] == ')') { ri->ptr++; ri->tokenType = ')'; ri->tokenValue = ri->ptr[0]; return; } else if (ri->ptr[0] == '[') { ri->ptr++; ri->tokenType = '['; ri->tokenValue = ri->ptr[0]; if (ri->ptr[1] == ']') { ri->ptr++; } return; } else if (ri->ptr[0] == '|'){ ri->ptr++; ri->tokenType = '|'; ri->tokenValue = 0; return; } else if (ri->ptr[0] == '*'){ ri->ptr++; ri->tokenType = '*'; ri->tokenValue = 0; return; } else if (ri->ptr[0] == '\\'){ // need more proccesing /* \277 \0xa5 \[ \\ \utf-8 etc... */ } else { ri->tokenType = 'a'; ri->tokenValue = ri->ptr[0]; return; } } ri->tokenType = 0; ri->tokenValue = 0; return; } // <regexAtom> ::= <literal>|<charClass>|<group> NodePtr regexAtom(RegexInfoPtr ri) { token(ri); NodePtr n = NULL; if (ri->tokenType == 'a') n = literal(ri); else if (ri->tokenType == '[') n = charClass(ri); else if (ri->tokenType == '(') n = group(ri); return n; } // <regex> ::= <regexAtom>|<regexAtom>'*'|<regexAtom>'|'<regex>|<regexAtom><regex> NodePtr regex(RegexInfoPtr ri) { NodePtr n = regexAtom(ri); while (ri->ptr[0]) { token(ri); if (ri->tokenType == '*') { n = createNode('*',n,0); } else if (ri->tokenType == '|') { NodePtr n1 = regex(ri); n = createNode('|',n,n1); } else if (ri->tokenType == ')') { return n; } else { NodePtr n1 = regex(ri); n = createNode('+',n,n1); } } return n; }