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收集整理的這篇文章主要介紹了
C++写的一个简单的词法分析器（分析C语言）
小編覺得挺不錯的,現在分享給大家,幫大家做個參考.
實驗用：
幾點注意：
1.代碼又長又臭，時間關系，沒有優化，冗余項多（我都看不下去了。囧）
2.加了一下簡單的錯誤檢測。（在mapping.h中定義了錯誤類型，可以查閱）
3.使用頭文件宏定義來表示單詞的各種屬性，也可以用文件
4.對于標志符的入口地址，無非是為了唯一識別，只要名字相同，都作為一個，使用自增的Int來模擬入口地址，即唯一標識。不考慮變量類型。
5.最后輸出有三個表：Token表，錯誤表，標志符表。
6.一個字符一個字符的讀文件，其實可以每次讀到一個固定長度的緩沖區，雙緩沖區進行分析。也可以讀每一行。
代碼：
mapping.h:
[cpp] view plaincopy
????????#define?AUTO?1??#define?BREAK?2??#define?CASE?3??#define?CHAR?4??#define?CONST?5??#define?CONTINUE?6??#define?DEFAULT?7??#define?DO?8??#define?DOUBLE?9??#define?ELSE?10??#define?ENUM?11??#define?EXTERN?12??#define?FLOAT?13??#define?FOR?14??#define?GOTO?15??#define?IF?16??#define?INT?17??#define?LONG?18??#define?REGISTER?19??#define?RETURN?20??#define?SHORT?21??#define?SIGNED?22??#define?SIZEOF?23??#define?STATIC?24??#define?STRUCT?25??#define?SWITCH?26??#define?TYPEDEF?27??#define?UNION?28??#define?UNSIGNED?29??#define?VOID?30??#define?VOLATILE?31??#define?WHILE?32??#define?KEY_DESC?"關鍵字"??????#define?IDENTIFER?40??#define?IDENTIFER_DESC?"標志符"??????#define?INT_VAL?51?//整形常量??#define?CHAR_VAL?52?//字符常量??#define?FLOAT_VAL?53?//浮點數常量??#define?STRING_VAL?54?//雙精度浮點數常量??#define?MACRO_VAL?55?//宏常量??#define?CONSTANT_DESC?"常量"??????#define?NOT?61???//?!??#define?BYTE_AND?62?//&??#define?COMPLEMENT?63?//?~??#define?BYTE_XOR??64?//?^??#define?MUL?65?//?*??#define?DIV?66//?/??#define?MOD?67?//?%??#define?ADD?68?//?+??#define?SUB?69?//?-??#define?LES_THAN?70?//?<??#define?GRT_THAN?71?//?>??#define?ASG?72?//?=??#define?ARROW?73?//?->??#define?SELF_ADD?74?//?++??#define?SELF_SUB?75?//?--??#define?LEFT_MOVE?76?//?<<??#define?RIGHT_MOVE?77?//?>>??#define?LES_EQUAL?78?//?<=??#define?GRT_EQUAL?79?//?>=??#define?EQUAL?80?//?==??#define?NOT_EQUAL?81?//?!=??#define?AND?82?//?&&??#define?OR?83?//?||??#define?COMPLETE_ADD?84?//?+=??#define?COMPLETE_SUB?85?//?-=??#define?COMPLETE_MUL?86?//?*=??#define?COMPLETE_DIV?87?//?/=??#define?COMPLETE_BYTE_XOR?88?//?^=??#define?COMPLETE_BYTE_AND?89?//?&=??#define?COMPLETE_COMPLEMENT?90?//?~=??#define?COMPLETE_MOD?91?//%=??#define?BYTE_OR?92?//?|????#define?OPE_DESC?"運算符"??????#define?LEFT_BRA?100?//?(??#define?RIGHT_BRA?101?//?)??#define?LEFT_INDEX?102?//?[??#define?RIGHT_INDEX?103?//?]??#define?L_BOUNDER?104?//??{??#define?R_BOUNDER?105?//?}??#define?POINTER?106?//?.??#define?JING?107?//?#??#define?UNDER_LINE?108?//?_??#define?COMMA?109?//?,??#define?SEMI?110?//?;??#define?SIN_QUE?111?//?'??#define?DOU_QUE?112?//?"????#define?CLE_OPE_DESC?"限界符"????#define?NOTE1?120?//?"/**/"注釋??#define?NOTE2?121?//?"//"注釋??#define?NOTE_DESC?"注釋"??????#define?HEADER?130?//頭文件??#define?HEADER_DESC?"頭文件"??????#define?FLOAT_ERROR?"float表示錯誤"??#define?FLOAT_ERROR_NUM?1??#define?DOUBLE_ERROR?"double表示錯誤"??#define?DOUBLE_ERROR_NUM?2??#define?NOTE_ERROR?"注釋沒有結束符"??#define?NOTE_ERROR_NUM?3??#define?STRING_ERROR?"字符串常量沒有結束符"??#define?STRING_ERROR_NUM?4??#define?CHARCONST_ERROR?"字符常量沒有結束符"??#define?CHARCONST_ERROR_NUM?5??#define?CHAR_ERROR?"非法字符"??#define?CHAR_ERROR_NUM?6??#define?LEFT_BRA_ERROR?"'('沒有對應項"??#define?LEFT_BRA_ERROR_NUM?7??#define?RIGHT_BRA_ERROR?"')'沒有對應項"??#define?RIGHT_BRA_ERROR_NUM?8??#define?LEFT_INDEX_ERROR?"'['沒有對應項"??#define?LEFT_INDEX_ERROR_NUM?9??#define?RIGHT_INDEX_ERROR?"']'沒有對應項"??#define?RIGHT_INDEX_ERROR_NUM?10??#define?L_BOUNDER_ERROR?"'{'沒有對應項"??#define?L_BOUNDER_ERROR_NUM?11??#define?R_BOUNDER_ERROR?"'}'沒有對應項"??#define?R_BOUNDER_ERROR_NUM?12??#define?PRE_PROCESS_ERROR?"預處理錯誤"?//頭文件或者宏定義錯誤??#define?PRE_PROCESS_ERROR_NUM??13????#define?_NULL?"無"??
main.cpp:
[cpp] view plaincopy
????#include?<iostream>??#include?<fstream>??#include?<stdio.h>??#include?<stdlib.h>??#include?<string.h>??#include?<iomanip>??#include?"mapping.h"????using?namespace?std;????const?char?*?key[]?=?{"auto","break","case","char","const","continue","default","do","double",????????????????????????"else","enum","extern","float","for","goto","if","int","long","register",????????????????????????"return","short","signed","sizeof","static","struct","switch","typedef",????????????????????????"union","unsigned","void","volatile","while"???????????????????????};??int?leftSmall?=?0;??int?rightSmall?=?0;??int?leftMiddle?=?0;??int?rightMiddle?=?0;??int?leftBig?=?0;??int?rightBig?=?0;??int?lineBra[6][1000]?=?{0};??int?static_iden_number?=?0;????struct?NormalNode??{??????char?content[30];??????char?describe[30];??????int?type;??????int?addr;??????int?line;??????NormalNode?*?next;??};????NormalNode?*?normalHead;??????struct?ErrorNode??{??????char?content[30];??????char?describe[30];??????int?type;??????int?line;??????ErrorNode?*?next;??};????ErrorNode?*?errorHead;??????struct?IdentiferNode??{??????char?content[30];??????char?describe[30];??????int?type;??????int?addr;??????int?line;??????IdentiferNode?*?next;??};??IdentiferNode?*?idenHead;??????void?initNode()??{??????normalHead?=?new?NormalNode();??????strcpy(normalHead->content,"");??????strcpy(normalHead->describe,"");??????normalHead->type?=?-1;??????normalHead->addr?=?-1;??????normalHead->line?=?-1;??????normalHead->next?=?NULL;????????errorHead?=?new?ErrorNode();??????strcpy(errorHead->content,"");??????strcpy(errorHead->describe,"");??????errorHead->line?=?-1;??????errorHead->next?=?NULL;????????idenHead?=?new?IdentiferNode();??????strcpy(idenHead->content,"");??????strcpy(idenHead->describe,"");??????idenHead->type?=?-1;??????idenHead->addr?=?-1;??????idenHead->line?=?-1;??????idenHead->next?=?NULL;??}????void?createNewNode(char?*?content,char?*descirbe,int?type,int?addr,int?line)??{??????NormalNode?*?p?=?normalHead;??????NormalNode?*?temp?=?new?NormalNode();????????while(p->next!=NULL)??????{??????????p?=?p->next;??????}????????strcpy(temp->content,content);??????strcpy(temp->describe,descirbe);??????temp->type?=?type;??????temp->addr?=?addr;??????temp->line?=?line;??????temp->next?=?NULL;????????p->next?=?temp;??}??void?createNewError(char?*?content,char?*descirbe,int?type,int?line)??{??????ErrorNode?*?p?=?errorHead;??????ErrorNode?*?temp?=?new?ErrorNode();????????strcpy(temp->content,content);??????strcpy(temp->describe,descirbe);??????temp->type?=?type;??????temp->line?=?line;??????temp->next?=?NULL;??????while(p->next!=NULL)??????{??????????p?=?p->next;??????}??????p->next?=?temp;??}????int?createNewIden(char?*?content,char?*descirbe,int?type,int?addr,int?line)??{??????IdentiferNode?*?p?=?idenHead;??????IdentiferNode?*?temp?=?new?IdentiferNode();??????int?flag?=?0;??????int?addr_temp?=?-2;??????while(p->next!=NULL)??????{??????????if(strcmp(content,p->next->content)?==?0)??????????{??????????????flag?=?1;??????????????addr_temp?=?p->next->addr;??????????}??????????p?=?p->next;??????}??????if(flag?==?0)??????{??????????addr_temp?=?++static_iden_number;??????}??????strcpy(temp->content,content);??????strcpy(temp->describe,descirbe);??????temp->type?=?type;??????temp->addr?=?addr_temp;??????temp->line?=?line;??????temp->next?=?NULL;??????p->next?=?temp;??????return?addr_temp;??}????void?printNodeLink()??{??????NormalNode?*?p?=?normalHead;??????p?=?p->next;??????cout<<"************************************分析表******************************"<<endl<<endl;??????cout<<setw(30)<<"內容"<<setw(10)<<"描述"<<"\t"<<"種別碼"<<"\t"<<"地址"<<"\t"<<"行號"<<endl;??????while(p!=NULL)??????{??????????if(p->type?==?IDENTIFER)??????????{??????????????cout<<setw(30)<<p->content<<setw(10)<<p->describe<<"\t"<<p->type<<"\t"<<p->addr<<"\t"<<p->line<<endl;??????????}??????????else??????????{??????????????cout<<setw(30)<<p->content<<setw(10)<<p->describe<<"\t"<<p->type<<"\t"<<"\t"<<p->line<<endl;??????????}??????????p?=?p->next;??????}??????cout<<endl<<endl;??}??????????????void?printErrorLink()??{??????ErrorNode?*?p?=?errorHead;??????p?=?p->next;??????cout<<"************************************錯誤表******************************"<<endl<<endl;??????cout<<setw(10)<<"內容"<<setw(30)<<"描述"<<"\t"<<"類型"<<"\t"<<"行號"<<endl;??????while(p!=NULL)??????{??????????cout<<setw(10)<<p->content<<setw(30)<<p->describe<<"\t"<<p->type<<"\t"<<p->line<<endl;??????????p?=?p->next;??????}??????cout<<endl<<endl;??}????void?printIdentLink()??{??????IdentiferNode?*?p?=?idenHead;??????p?=?p->next;??????cout<<"************************************標志符表******************************"<<endl<<endl;??????cout<<setw(30)<<"內容"<<setw(10)<<"描述"<<"\t"<<"種別碼"<<"\t"<<"地址"<<"\t"<<"行號"<<endl;??????while(p!=NULL)??????{??????????cout<<setw(30)<<p->content<<setw(10)<<p->describe<<"\t"<<p->type<<"\t"<<p->addr<<"\t"<<p->line<<endl;??????????p?=?p->next;??????}??????cout<<endl<<endl;??}??int?mystrlen(char?*?word)??{??????if(*word?==?'\0')??????{??????????return?0;??????}??????else??????{??????????return?1+mystrlen(word+1);??????}??}????void?preProcess(char?*?word,int?line)??{??????const?char?*?include_temp?=?"include";??????const?char?*?define_temp?=?"define";??????char?*?p_include,*p_define;??????int?flag?=?0;??????p_include?=?strstr(word,include_temp);??????if(p_include!=NULL)??????{??????????flag?=?1;??????????int?i;??????????for(i=7;;)??????????{??????????????if(*(p_include+i)?==?'?'?||?*(p_include+i)?==?'\t')??????????????{??????????????????i++;??????????????}??????????????else??????????????{??????????????????break;??????????????}??????????}??????????createNewNode(p_include+i,HEADER_DESC,HEADER,-1,line);??????}??????else??????{??????????p_define?=?strstr(word,define_temp);??????????if(p_define!=NULL)??????????{??????????????flag?=?1;??????????????int?i;??????????????for(i=7;;)??????????????{??????????????????if(*(p_define+i)?==?'?'?||?*(p_define+i)?==?'\t')??????????????????{??????????????????????i++;??????????????????}??????????????????else??????????????????{??????????????????????break;??????????????????}??????????????}??????????????createNewNode(p_define+i,CONSTANT_DESC,MACRO_VAL,-1,line);??????????}??????}??????if(flag?==?0)??????{??????????createNewError(word,PRE_PROCESS_ERROR,PRE_PROCESS_ERROR_NUM,line);??????}??}????void?close()??{??????delete?idenHead;??????delete?errorHead;??????delete?normalHead;??}????int?seekKey(char?*?word)??{??????for(int?i=0;?i<32;?i++)??????{??????????if(strcmp(word,key[i])?==?0)??????????{??????????????return?i+1;??????????}??????}??????return?IDENTIFER;??}????void?scanner()??{??????char?filename[30];??????char?ch;??????char?array[30];??????char?*?word;??????int?i;??????int?line?=?1;??????????FILE?*?infile;??????printf("請輸入要進行語法分析的C語言程序：\n");??????scanf("%s",filename);??????infile?=?fopen(filename,"r");??????while(!infile)??????{??????????printf("打開文件失敗！\n");??????????return;??????}??????ch?=?fgetc(infile);??????while(ch!=EOF)??????{????????????i?=?0;????????????????????if((ch>='A'?&&?ch<='Z')?||?(ch>='a'?&&?ch<='z')?||?ch?==?'_')??????????{??????????????while((ch>='A'?&&?ch<='Z')||(ch>='a'?&&?ch<='z')||(ch>='0'?&&?ch<='9')?||?ch?==?'_')??????????????{??????????????????array[i++]?=?ch;??????????????????ch?=?fgetc(infile);??????????????}??????????????word?=?new?char[i+1];??????????????memcpy(word,array,i);??????????????word[i]?=?'\0';??????????????int?seekTemp?=?seekKey(word);??????????????if(seekTemp!=IDENTIFER)??????????????{??????????????????createNewNode(word,KEY_DESC,seekTemp,-1,line);??????????????}??????????????else??????????????{??????????????????int?addr_tmp?=?createNewIden(word,IDENTIFER_DESC,seekTemp,-1,line);??????????????????createNewNode(word,IDENTIFER_DESC,seekTemp,addr_tmp,line);??????????????}??????????????fseek(infile,-1L,SEEK_CUR);??????????}????????????????????else?if(ch?>='0'?&&?ch<='9')??????????{??????????????int?flag?=?0;??????????????int?flag2?=?0;????????????????????????????while(ch?>='0'?&&?ch<='9')??????????????{??????????????????array[i++]?=?ch;??????????????????ch?=?fgetc(infile);??????????????}????????????????????????????if(ch?==?'.')??????????????{??????????????????flag2?=?1;??????????????????array[i++]?=?ch;??????????????????ch?=?fgetc(infile);??????????????????if(ch>='0'?&&?ch<='9')??????????????????{??????????????????????while(ch>='0'?&&?ch<='9')??????????????????????{??????????????????????????array[i++]?=?ch;??????????????????????????ch?=?fgetc(infile);??????????????????????}??????????????????}??????????????????else??????????????????{??????????????????????flag?=?1;??????????????????}??????????????????????????????????????if(ch?==?'E'?||?ch?==?'e')??????????????????{??????????????????????array[i++]?=?ch;??????????????????????ch?=?fgetc(infile);??????????????????????if(ch?==?'+'?||?ch?==?'-')??????????????????????{??????????????????????????array[i++]?=?ch;??????????????????????????ch?=?fgetc(infile);??????????????????????}??????????????????????if(ch?>='0'?&&?ch<='9')??????????????????????{??????????????????????????array[i++]?=?ch;??????????????????????????ch?=?fgetc(infile);??????????????????????}??????????????????????else??????????????????????{??????????????????????????flag?=?2;??????????????????????}??????????????????}????????????????}??????????????word?=?new?char[i+1];??????????????memcpy(word,array,i);??????????????word[i]?=?'\0';??????????????if(flag?==?1)??????????????{??????????????????createNewError(word,FLOAT_ERROR,FLOAT_ERROR_NUM,line);??????????????}??????????????else?if(flag?==?2)??????????????{??????????????????createNewError(word,DOUBLE_ERROR,DOUBLE_ERROR_NUM,line);??????????????}??????????????else??????????????{??????????????????if(flag2?==?0)??????????????????{??????????????????????createNewNode(word,CONSTANT_DESC,INT_VAL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode(word,CONSTANT_DESC,FLOAT_VAL,-1,line);??????????????????}??????????????}??????????????fseek(infile,-1L,SEEK_CUR);??????????}????????????????????else?if(ch?==?'/')??????????{??????????????ch?=?fgetc(infile);????????????????????????????if(ch?==?'=')??????????????{??????????????????createNewNode("/=",OPE_DESC,COMPLETE_DIV,-1,line);??????????????}????????????????????????????else?if(ch?==?'*')??????????????{??????????????????ch?=??fgetc(infile);??????????????????while(1)??????????????????{??????????????????????while(ch?!=?'*')??????????????????????{??????????????????????????if(ch?==?'\n')??????????????????????????{??????????????????????????????line++;??????????????????????????}??????????????????????????ch?=?fgetc(infile);??????????????????????????if(ch?==?EOF)??????????????????????????{??????????????????????????????createNewError(_NULL,NOTE_ERROR,NOTE_ERROR_NUM,line);??????????????????????????????return;??????????????????????????}??????????????????????}??????????????????????ch?=?fgetc(infile);??????????????????????if(ch?==?'/')??????????????????????{??????????????????????????break;??????????????????????}??????????????????????if(ch?==?EOF)??????????????????????{??????????????????????????createNewError(_NULL,NOTE_ERROR,NOTE_ERROR_NUM,line);??????????????????????????return;??????????????????????}??????????????????}??????????????????createNewNode(_NULL,NOTE_DESC,NOTE1,-1,line);??????????????}????????????????????????????else?if(ch?==?'/')??????????????{??????????????????while(ch!='\n')??????????????????{??????????????????????ch?=?fgetc(infile);??????????????????????if(ch?==?EOF)??????????????????????{??????????????????????????createNewNode(_NULL,NOTE_DESC,NOTE2,-1,line);??????????????????????????return;??????????????????????}??????????????????}??????????????????line++;??????????????????createNewNode(_NULL,NOTE_DESC,NOTE2,-1,line);??????????????????if(ch?==?EOF)??????????????????{??????????????????????return;??????????????????}??????????????}????????????????????????????else??????????????{??????????????????createNewNode("/",OPE_DESC,DIV,-1,line);??????????????}??????????}????????????????????else?if(ch?==?'"')??????????{??????????????createNewNode("\"",CLE_OPE_DESC,DOU_QUE,-1,line);??????????????ch?=?fgetc(infile);??????????????i?=?0;??????????????while(ch!='"')??????????????{??????????????????array[i++]?=?ch;??????????????????if(ch?==?'\n')??????????????????{??????????????????????line++;??????????????????}??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?EOF)??????????????????{??????????????????????createNewError(_NULL,STRING_ERROR,STRING_ERROR_NUM,line);??????????????????????return;??????????????????}??????????????}??????????????word?=?new?char[i+1];??????????????memcpy(word,array,i);??????????????word[i]?=?'\0';??????????????createNewNode(word,CONSTANT_DESC,STRING_VAL,-1,line);??????????????createNewNode("\"",CLE_OPE_DESC,DOU_QUE,-1,line);??????????}????????????????????else?if(ch?==?'\'')??????????{??????????????createNewNode("\'",CLE_OPE_DESC,SIN_QUE,-1,line);??????????????ch?=?fgetc(infile);??????????????i?=?0;??????????????while(ch!='\'')??????????????{??????????????????array[i++]?=?ch;??????????????????if(ch?==?'\n')??????????????????{??????????????????????line++;??????????????????}??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?EOF)??????????????????{??????????????????????createNewError(_NULL,CHARCONST_ERROR,CHARCONST_ERROR_NUM,line);??????????????????????return;??????????????????}??????????????}??????????????word?=?new?char[i+1];??????????????memcpy(word,array,i);??????????????word[i]?=?'\0';??????????????createNewNode(word,CONSTANT_DESC,CHAR_VAL,-1,line);??????????????createNewNode("\'",CLE_OPE_DESC,SIN_QUE,-1,line);??????????}??????????else?if(ch?==?'?'?||?ch?==?'\t'?||?ch?==?'\r'?||?ch?==?'\n')??????????{??????????????if(ch?==?'\n')??????????????{??????????????????line++;??????????????}??????????}??????????else??????????{??????????????if(ch?==?EOF)??????????????{??????????????????return;??????????????}????????????????????????????else?if(ch?==?'#')??????????????{??????????????????while(ch!='\n'?&&?ch!=EOF)??????????????????{??????????????????????array[i++]?=?ch;??????????????????????ch?=?fgetc(infile);??????????????????}??????????????????word?=?new?char[i+1];??????????????????memcpy(word,array,i);??????????????????word[i]?=?'\0';??????????????????preProcess(word,line);????????????????????fseek(infile,-1L,SEEK_CUR);??????????????}????????????????????????????else?if(ch?==?'-')??????????????{??????????????????array[i++]?=?ch;??????????????????ch?=?fgetc(infile);??????????????????if(ch?>='0'?&&?ch<='9')??????????????????{??????????????????????int?flag?=?0;??????????????????????int?flag2?=?0;????????????????????????????????????????????while(ch>='0'?&&?ch<='9')??????????????????????{??????????????????????????array[i++]?=?ch;??????????????????????????ch?=?fgetc(infile);??????????????????????}????????????????????????????????????????????if(ch?==?'.')??????????????????????{??????????????????????????flag2?=?1;??????????????????????????array[i++]?=?ch;??????????????????????????ch?=?fgetc(infile);??????????????????????????if(ch>='0'?&&?ch<='9')??????????????????????????{??????????????????????????????while(ch>='0'?&&?ch<='9')??????????????????????????????{??????????????????????????????????array[i++]?=?ch;??????????????????????????????????ch?=?fgetc(infile);??????????????????????????????}??????????????????????????}??????????????????????????else??????????????????????????{??????????????????????????????flag?=?1;??????????????????????????}????????????????????????????????????????????????????if(ch?==?'E'?||?ch?==?'e')??????????????????????????{??????????????????????????????array[i++]?=?ch;??????????????????????????????ch?=?fgetc(infile);??????????????????????????????if(ch?==?'+'?||?ch?==?'-')??????????????????????????????{??????????????????????????????????array[i++]?=?ch;??????????????????????????????????ch?=?fgetc(infile);??????????????????????????????}??????????????????????????????if(ch?>='0'?&&?ch<='9')??????????????????????????????{??????????????????????????????????array[i++]?=?ch;??????????????????????????????????ch?=?fgetc(infile);??????????????????????????????}??????????????????????????????else??????????????????????????????{??????????????????????????????????flag?=?2;??????????????????????????????}??????????????????????????}??????????????????????}??????????????????????word?=?new?char[i+1];??????????????????????memcpy(word,array,i);??????????????????????word[i]?=?'\0';??????????????????????if(flag?==?1)??????????????????????{??????????????????????????createNewError(word,FLOAT_ERROR,FLOAT_ERROR_NUM,line);??????????????????????}??????????????????????else?if(flag?==?2)??????????????????????{??????????????????????????createNewError(word,DOUBLE_ERROR,DOUBLE_ERROR_NUM,line);??????????????????????}??????????????????????else??????????????????????{??????????????????????????if(flag2?==?0)??????????????????????????{??????????????????????????????createNewNode(word,CONSTANT_DESC,INT_VAL,-1,line);??????????????????????????}??????????????????????????else??????????????????????????{??????????????????????????????createNewNode(word,CONSTANT_DESC,FLOAT_VAL,-1,line);??????????????????????????}??????????????????????}??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????????else?if(ch?==?'>')??????????????????{??????????????????????createNewNode("->",OPE_DESC,ARROW,-1,line);??????????????????}??????????????????else?if(ch?==?'-')??????????????????{??????????????????????createNewNode("--",OPE_DESC,SELF_SUB,-1,line);??????????????????}??????????????????else?if(ch?==?'=')??????????????????{??????????????????????createNewNode("--",OPE_DESC,SELF_SUB,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("-",OPE_DESC,SUB,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'+')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'+')??????????????????{??????????????????????createNewNode("++",OPE_DESC,SELF_ADD,-1,line);??????????????????}??????????????????else?if(ch?==?'=')??????????????????{??????????????????????createNewNode("+=",OPE_DESC,COMPLETE_ADD,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("+",OPE_DESC,ADD,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'*')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("*=",OPE_DESC,COMPLETE_MUL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("*",OPE_DESC,MUL,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'^')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("^=",OPE_DESC,COMPLETE_BYTE_XOR,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("^",OPE_DESC,BYTE_XOR,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'%')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("%=",OPE_DESC,COMPLETE_MOD,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("%",OPE_DESC,MOD,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'&')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("&=",OPE_DESC,COMPLETE_BYTE_AND,-1,line);??????????????????}??????????????????else?if(ch?==?'&')??????????????????{??????????????????????createNewNode("&&",OPE_DESC,AND,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("&",OPE_DESC,BYTE_AND,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'~')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("~=",OPE_DESC,COMPLETE_COMPLEMENT,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("~",OPE_DESC,COMPLEMENT,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'!')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("!=",OPE_DESC,NOT_EQUAL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("!",OPE_DESC,NOT,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'<')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'<')??????????????????{??????????????????????createNewNode("<<",OPE_DESC,LEFT_MOVE,-1,line);??????????????????}??????????????????else?if(ch?==?'=')??????????????????{??????????????????????createNewNode("<=",OPE_DESC,LES_EQUAL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("<",OPE_DESC,LES_THAN,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'>')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'>')??????????????????{??????????????????????createNewNode(">>",OPE_DESC,RIGHT_MOVE,-1,line);??????????????????}??????????????????else?if(ch?==?'=')??????????????????{??????????????????????createNewNode(">=",OPE_DESC,GRT_EQUAL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode(">",OPE_DESC,GRT_THAN,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}????????????????????????????else?if(ch?==?'|')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'|')??????????????????{??????????????????????createNewNode("||",OPE_DESC,OR,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("|",OPE_DESC,BYTE_OR,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}??????????????else?if(ch?==?'=')??????????????{??????????????????ch?=?fgetc(infile);??????????????????if(ch?==?'=')??????????????????{??????????????????????createNewNode("==",OPE_DESC,EQUAL,-1,line);??????????????????}??????????????????else??????????????????{??????????????????????createNewNode("=",OPE_DESC,ASG,-1,line);??????????????????????fseek(infile,-1L,SEEK_CUR);??????????????????}??????????????}??????????????else?if(ch?==?'(')??????????????{??????????????????leftSmall++;??????????????????lineBra[0][leftSmall]?=?line;??????????????????createNewNode("(",CLE_OPE_DESC,LEFT_BRA,-1,line);??????????????}??????????????else?if(ch?==?')')??????????????{??????????????????rightSmall++;??????????????????lineBra[1][rightSmall]?=?line;??????????????????createNewNode(")",CLE_OPE_DESC,RIGHT_BRA,-1,line);??????????????}??????????????else?if(ch?==?'[')??????????????{??????????????????leftMiddle++;??????????????????lineBra[2][leftMiddle]?=?line;??????????????????createNewNode("[",CLE_OPE_DESC,LEFT_INDEX,-1,line);??????????????}??????????????else?if(ch?==?']')??????????????{??????????????????rightMiddle++;??????????????????lineBra[3][rightMiddle]?=?line;??????????????????createNewNode("]",CLE_OPE_DESC,RIGHT_INDEX,-1,line);??????????????}??????????????else?if(ch?==?'{')??????????????{??????????????????leftBig++;??????????????????lineBra[4][leftBig]?=?line;??????????????????createNewNode("{",CLE_OPE_DESC,L_BOUNDER,-1,line);??????????????}??????????????else?if(ch?==?'}')??????????????{??????????????????rightBig++;??????????????????lineBra[5][rightBig]?=?line;??????????????????createNewNode("}",CLE_OPE_DESC,R_BOUNDER,-1,line);??????????????}??????????????else?if(ch?==?'.')??????????????{??????????????????createNewNode(".",CLE_OPE_DESC,POINTER,-1,line);??????????????}??????????????else?if(ch?==?',')??????????????{??????????????????createNewNode(",",CLE_OPE_DESC,COMMA,-1,line);??????????????}??????????????else?if(ch?==?';')??????????????{??????????????????createNewNode(";",CLE_OPE_DESC,SEMI,-1,line);??????????????}??????????????else??????????????{??????????????????char?temp[2];??????????????????temp[0]?=?ch;??????????????????temp[1]?=?'\0';??????????????????createNewError(temp,CHAR_ERROR,CHAR_ERROR_NUM,line);??????????????}??????????}??????????ch?=?fgetc(infile);??????}??}??void?BraMappingError()??{??????if(leftSmall?!=?rightSmall)??????{??????????int?i?=?(leftSmall>rightSmall)???(leftSmall-rightSmall)?:?(rightSmall?-?leftSmall);??????????bool??flag?=?(leftSmall>rightSmall)???true?:?false;??????????if(flag)??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,LEFT_BRA_ERROR,LEFT_BRA_ERROR_NUM,lineBra[0][i+1]);??????????????}??????????}??????????else??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,RIGHT_BRA_ERROR,RIGHT_BRA_ERROR_NUM,lineBra[1][i+1]);??????????????}??????????}??????}??????if(leftMiddle?!=?rightMiddle)??????{??????????int?i?=?(leftMiddle>rightMiddle)???(leftMiddle-rightMiddle)?:?(rightMiddle?-?leftMiddle);??????????bool?flag?=?(leftMiddle>rightMiddle)???true?:?false;??????????if(flag)??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,LEFT_INDEX_ERROR,LEFT_INDEX_ERROR_NUM,lineBra[2][i+1]);??????????????}??????????}??????????else??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,RIGHT_INDEX_ERROR,RIGHT_INDEX_ERROR_NUM,lineBra[3][i+1]);??????????????}??????????}??????}??????if(leftBig?!=?rightBig)??????{??????????int?i?=?(leftBig>rightBig)???(leftBig-rightBig)?:?(rightBig?-?leftSmall);??????????bool?flag?=?(leftBig>rightBig)???true?:?false;??????????if(flag)??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,L_BOUNDER_ERROR,L_BOUNDER_ERROR_NUM,lineBra[4][i+1]);??????????????}??????????}??????????else??????????{??????????????while(i--)??????????????{??????????????????createNewError(_NULL,R_BOUNDER_ERROR,R_BOUNDER_ERROR_NUM,lineBra[5][i+1]);??????????????}??????????}??????}??}????int?main()??{??????initNode();??????scanner();??????BraMappingError();??????printNodeLink();??????printErrorLink();??????printIdentLink();??????close();??????return?0;??}??
測試的C文件：test.c(一個錯誤很多的C程序)
[cpp] view plaincopy
#include??????????<stdio.h>??#include?"my.h"??#define?max?90??#de?some????int?char?main()??{??????8888char?yn;??????do??????{??????int?9801;??????float?9.;??????double?9.ef;??????float?-9.876;??????double?hello.8.9;??????float?7.9e-5;??????int?e-5;??????a?/=?6;??????????init();???????????scanner();??????????printf("Are?You?continue(y/n)\n");??????????yn=getch();??????if(a?==?7)??????{????????????????}??????else??????{????????????????}??@????????}??????while(yn=='y'||yn=='Y');????????????return?0;??[hello????????????????????????????????printf("hello");??????/*我是頭豬????????
程序運行結果：
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請輸入要進行語法分析的C語言程序：??test.c??************************************分析表******************************??????????????????????????????內容??????描述????????種別碼??地址????行號???????????????????????<stdio.h>????頭文件????????130?????????????1??????????????????????????"my.h"????頭文件????????130?????????????2??????????????????????????max?90??????常量????????55??????????????3?????????????????????????????int????關鍵字????????17??????????????6????????????????????????????char????關鍵字????????4???????????????6????????????????????????????main????標志符????????40??????1???????6???????????????????????????????(????限界符????????100?????????????6???????????????????????????????)????限界符????????101?????????????6???????????????????????????????{????限界符????????104?????????????7????????????????????????????8888??????常量????????51??????????????8????????????????????????????char????關鍵字????????4???????????????8??????????????????????????????yn????標志符????????40??????2???????8???????????????????????????????;????限界符????????110?????????????8??????????????????????????????do????關鍵字????????8???????????????9???????????????????????????????{????限界符????????104?????????????10?????????????????????????????int????關鍵字????????17??????????????11????????????????????????????9801??????常量????????51??????????????11???????????????????????????????;????限界符????????110?????????????11???????????????????????????float????關鍵字????????13??????????????12???????????????????????????????;????限界符????????110?????????????12??????????????????????????double????關鍵字????????9???????????????13???????????????????????????????f????標志符????????40??????3???????13???????????????????????????????;????限界符????????110?????????????13???????????????????????????float????關鍵字????????13??????????????14??????????????????????????-9.876??????常量????????53??????????????14???????????????????????????????;????限界符????????110?????????????14??????????????????????????double????關鍵字????????9???????????????15???????????????????????????hello????標志符????????40??????4???????15???????????????????????????????.????限界符????????106?????????????15?????????????????????????????8.9??????常量????????53??????????????15???????????????????????????????;????限界符????????110?????????????15???????????????????????????float????關鍵字????????13??????????????16??????????????????????????7.9e-5??????常量????????53??????????????16???????????????????????????????;????限界符????????110?????????????16?????????????????????????????int????關鍵字????????17??????????????17???????????????????????????????e????標志符????????40??????5???????17??????????????????????????????-5??????常量????????51??????????????17???????????????????????????????;????限界符????????110?????????????17???????????????????????????????a????標志符????????40??????6???????18??????????????????????????????/=????運算符????????87??????????????18???????????????????????????????6??????常量????????51??????????????18???????????????????????????????;????限界符????????110?????????????18????????????????????????????init????標志符????????40??????7???????19???????????????????????????????(????限界符????????100?????????????19???????????????????????????????)????限界符????????101?????????????19???????????????????????????????;????限界符????????110?????????????19??????????????????????????????無??????注釋????????120?????????????19?????????????????????????scanner????標志符????????40??????8???????20???????????????????????????????(????限界符????????100?????????????20???????????????????????????????)????限界符????????101?????????????20???????????????????????????????;????限界符????????110?????????????20??????????????????????????????無??????注釋????????121?????????????21??????????????????????????printf????標志符????????40??????9???????21???????????????????????????????(????限界符????????100?????????????21???????????????????????????????"????限界符????????112?????????????21?????????Are?You?continue(y/n)\n??????常量????????54??????????????21???????????????????????????????"????限界符????????112?????????????21???????????????????????????????)????限界符????????101?????????????21???????????????????????????????;????限界符????????110?????????????21??????????????????????????????yn????標志符????????40??????2???????22???????????????????????????????=????運算符????????72??????????????22???????????????????????????getch????標志符????????40??????10??????22???????????????????????????????(????限界符????????100?????????????22???????????????????????????????)????限界符????????101?????????????22???????????????????????????????;????限界符????????110?????????????22??????????????????????????????if????關鍵字????????16??????????????23???????????????????????????????(????限界符????????100?????????????23???????????????????????????????a????標志符????????40??????6???????23??????????????????????????????==????運算符????????80??????????????23???????????????????????????????7??????常量????????51??????????????23???????????????????????????????)????限界符????????101?????????????23???????????????????????????????{????限界符????????104?????????????24???????????????????????????????}????限界符????????105?????????????26????????????????????????????else????關鍵字????????10??????????????27???????????????????????????????{????限界符????????104?????????????28???????????????????????????????}????限界符????????105?????????????30???????????????????????????????}????限界符????????105?????????????33???????????????????????????while????關鍵字????????32??????????????34???????????????????????????????(????限界符????????100?????????????34??????????????????????????????yn????標志符????????40??????2???????34??????????????????????????????==????運算符????????80??????????????34???????????????????????????????'????限界符????????111?????????????34???????????????????????????????y??????常量????????52??????????????34???????????????????????????????'????限界符????????111?????????????34??????????????????????????????||????運算符????????83??????????????34??????????????????????????????yn????標志符????????40??????2???????34??????????????????????????????==????運算符????????80??????????????34???????????????????????????????'????限界符????????111?????????????34???????????????????????????????Y??????常量????????52??????????????34???????????????????????????????'????限界符????????111?????????????34???????????????????????????????)????限界符????????101?????????????34???????????????????????????????;????限界符????????110?????????????34??????????????????????????return????關鍵字????????20??????????????36???????????????????????????????0??????常量????????51??????????????36???????????????????????????????;????限界符????????110?????????????36???????????????????????????????[????限界符????????102?????????????37???????????????????????????hello????標志符????????40??????4???????37??????????????????????????????無??????注釋????????121?????????????43??????????????????????????????無??????注釋????????121?????????????45??????????????????????????????無??????注釋????????121?????????????46??????????????????????????printf????標志符????????40??????9???????47???????????????????????????????(????限界符????????100?????????????47???????????????????????????????"????限界符????????112?????????????47???????????????????????????hello??????常量????????54??????????????47???????????????????????????????"????限界符????????112?????????????47???????????????????????????????)????限界符????????101?????????????47???????????????????????????????;????限界符????????110?????????????47??????************************************錯誤表******************************??????????內容??????????????????????????描述????????類型????行號????#de?some????????????????????預處理錯誤????????13??????4??????????9.?????????????????float表示錯誤????????1???????12?????????9.e????????????????double表示錯誤????????2???????13???????????@??????????????????????非法字符????????6???????31??????????無????????????????注釋沒有結束符????????3???????49??????????無?????????????????'['沒有對應項????????9???????37??????????無?????????????????'{'沒有對應項????????11??????7??????************************************標志符表******************************??????????????????????????????內容??????描述????????種別碼??地址????行號????????????????????????????main????標志符????????40??????1???????6??????????????????????????????yn????標志符????????40??????2???????8???????????????????????????????f????標志符????????40??????3???????13???????????????????????????hello????標志符????????40??????4???????15???????????????????????????????e????標志符????????40??????5???????17???????????????????????????????a????標志符????????40??????6???????18????????????????????????????init????標志符????????40??????7???????19?????????????????????????scanner????標志符????????40??????8???????20??????????????????????????printf????標志符????????40??????9???????21??????????????????????????????yn????標志符????????40??????2???????22???????????????????????????getch????標志符????????40??????10??????22???????????????????????????????a????標志符????????40??????6???????23??????????????????????????????yn????標志符????????40??????2???????34??????????????????????????????yn????標志符????????40??????2???????34???????????????????????????hello????標志符????????40??????4???????37??????????????????????????printf????標志符????????40??????9???????47????????Process?returned?0?(0x0)???execution?time?:?5.629?s??Press?any?key?to?continue.?
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