plxcompile.cs

编译器

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

namespace PlxCompiler
{

    class PlxCompile
    {
        //一些数组的上界
        const int MAX_LINECHAR = 1024;
        const int MAX_NUMBERSIZE = 14;
        const int MAX_ANSICNUMBER = 128;
        const int MAX_INDENTFIERLEN = 36;
        const int MAX_INDENTNUMBER = 1024;
        const int MAX_CODENUMBER = 2048;
        const int MAX_STACKLIMIT = 2048;
        const int MAX_KEYWORD = 32;
        const int MAX_ERROR = 100;

        //
        const int plus = 0;                 //    +     
        const int minus = 1;                //    -     
        const int times = 2;                //    *    
        const int slash = 3;                //    /     
        const int remainder = 42;           //    %
        const int cifang = 43;                 //    x^y  ^
        const int lparen = 4;               //    (     
        const int rparen = 5;               //    )     
        const int eql = 6;                  //    =     
        const int comma = 7;                //    ,     
        const int semicolon = 8;            //    ;     
        const int period = 9;               //    .     
        const int lss = 10;                 //    <    
        const int gtr = 11;                 //    >    
        const int ident = 12;               //         
        const int number = 14;              //         
        const int becomes = 15;             //    :=    
        const int geq = 16;                 //    >=   
        const int leq = 17;                 //    <=   
        const int neql = 18;                //    /=   
        const int nul = 19;                 //         

        const int progsym = 20;
        const int intesym = 21;
        const int logisym = 22;
        const int constsym = 23;
        const int ifsym = 24;
        const int thensym = 25;
        const int elsesym = 26;
        const int whilesym = 27;
        const int repeasym = 28;
        const int beginsym = 29;
        const int endsym = 30;
        const int orsym = 31;
        const int andsym = 32;
        const int xorsym = 42;
        const int notsym = 33;
        const int truesym = 34;
        const int falsesym = 35;
        const int dosym = 36;
        const int untilsym = 37;
        const int writesym = 38;
        const int procsym = 39;
        const int callsym = 40;
        const int term = 41;            /*  结束    */
        const int commentsym = 100;

        public Form1 form1;
        //构造函数
        public PlxCompile(Form1 parent)
        {
            cc = ll = 0;
            tx = 0;                   /* 用0专门来做查询 */
            cx = 0;
            dx = 0;
            lev = 0;

            errornum = 0;

            lineIndex = 1;
            //各种数组的实例化
            id = "";
            word = new string[MAX_KEYWORD];
            line = "";          //当前行字符  
            wsym = new int[MAX_KEYWORD];            //关键字索引  
            a = "";        //标识符缓存  
            ssym = new int[MAX_ANSICNUMBER];        //运算符索引  
            s = new int[MAX_STACKLIMIT];            //运行栈      
            code = new CODE[MAX_CODENUMBER];        //存储代码的数组
            table = new TABLE[MAX_INDENTNUMBER];
            errorMax = MAX_ERROR;
            form1 = parent;


            word[0] = "program";
            word[1] = "integer";
            word[2] = "logical";
            word[3] = "const";
            word[4] = "if";
            word[5] = "then";
            word[6] = "else";
            word[7] = "while";
            word[8] = "repeat";
            word[9] = "begin";
            word[10] = "end";
            word[11] = "or";
            word[12] = "and";
            word[13] = "not";
            word[14] = "true";
            word[15] = "false";
            word[16] = "do";
            word[17] = "until";
            word[18] = "write";
            word[19] = "procedure";
            word[20] = "call";
            word[21] = "xor";

            wsym[0] = progsym;
            wsym[1] = intesym;
            wsym[2] = logisym;
            wsym[3] = constsym;
            wsym[4] = ifsym;
            wsym[5] = thensym;
            wsym[6] = elsesym;
            wsym[7] = whilesym;
            wsym[8] = repeasym;
            wsym[9] = beginsym;
            wsym[10] = endsym;
            wsym[11] = orsym;
            wsym[12] = andsym;
            wsym[13] = notsym;
            wsym[14] = truesym;
            wsym[15] = falsesym;
            wsym[16] = dosym;
            wsym[17] = untilsym;
            wsym[18] = writesym;
            wsym[19] = procsym;
            wsym[20] = callsym;
            wsym[21] = xorsym;

            for (int i = 0; i < 128; i++)
                ssym[i] = -1;

            ssym['+'] = plus;
            ssym['-'] = minus;
            ssym['*'] = times;
            ssym['/'] = slash;
            ssym['%'] = remainder;
            ssym['^'] = cifang;
            ssym['('] = lparen;
            ssym[')'] = rparen;
            ssym['='] = eql;
            ssym[','] = comma;
            ssym[';'] = semicolon;
            ssym['.'] = period;
            ssym['<'] = lss;
            ssym['>'] = gtr;
            ssym['$'] = term;

        }

        // 文件操作
        public void FileOpen(string filename)
        {
            try
            {
                FileIn = File.OpenText(filename);
            }
            catch (Exception e)
            {
                error(0);
            }
        }
        public void FileOpen()
        {
            try
            {
                FileIn = File.OpenText(FilePath);
            }
            catch (IOException e)
            {
                error(0);
            }
        }
        public bool FileClose()
        {
            try
            {
                FileIn.Close();
                return true;
            }
            catch (IOException e)
            {
                error(-1);
                return false;
            }
        }
        private string FilePath;
        private StreamReader FileIn;

        private void error(string a)
        {
            errornum++;
            if (errornum > errorMax) return;
            form1.outerror("ERROR"+errornum+" 行号: "+(lineIndex-1)+":列号: "+ll+" "+line+ch+ " "+  a+"\r\n");
            
        }
        private void error(string a, int b)
        {
            errornum++;
            if (errornum > errorMax) return;
            form1.outerror("ERROR" + errornum + " 行号-" + (lineIndex - 1) + ":列号-" + ll + " " + line + a + "\r\n");
        }
        private void error(int errorNo)
        {
            errornum++;
            if (errornum > errorMax) return;

        }

        // 词法分析  
        int cc;                         //当前字符号  
        int ll;                         //当前行数目  
        string line;                    //当前行字符  
        char ch;                        //当前读取字符
        int lineIndex;                  //当前行号    

        string[] word;                  //关键字串   
        int[] wsym;                     //关键字索引 
        string a;                       //标识符缓存  
        int[] ssym;                     //运算符索引  

        string id;                      //三种变量缓存
        int sym;
        int num;

        void getch()
        {
            if (cc != ll)
            {
                ch = line[cc++];
                return;

            }
            else
            {
                if (FileIn.EndOfStream)
                {
                    ch = '$';
                    return;
                }
            }

            cc = ll = 0;

            lineIndex++;
            //char[] temp = (FileIn.ReadLine()).ToCharArray();
            line = FileIn.ReadLine() + " "; //temp;
            ll = line.Length;
            //line[ll++] = ' ';

            ch = line[cc++];
        }
        void getsym()
        {
            while (ch == ' ' || ch == 9) getch();

            /* 字符串识别 */
            if (ch <= 'z' && ch >= 'a')
            {
                int i = 0;
                a = "";

                do
                {
                    if (i < MAX_INDENTFIERLEN - 1)
                    {
                        //a.Insert(i++,ch+"");
                        a = a + ch;
                        i++;

                    }
                    else
                    {
                        break;
                    }
                    getch();
                }
                while ((ch <= 'z' && ch >= 'a') || (ch <= '9' && ch >= '0'));
                id = String.Copy(a);
                sym = ident;

                for (i = 0; i < MAX_KEYWORD; i++)
                {

                    if (id.Equals(word[i]))
                    {
                        sym = wsym[i]; break;
                    }
                }
            }
            else
            {
                /* 数字识别 */
                if (ch <= '9' && ch >= '0')
                {
                    int i = 0;
                    num = 0;

                    do
                    {
                        i++;
                        num = 10 * num + ((int)ch - '0');
                        getch();
                    }
                    while (ch <= '9' && ch >= '0');

                    if (i > MAX_NUMBERSIZE)
                    {
                        error("数字的位数超出范围!");
                    }

                    sym = number;

                }
                else
                {
                    /* 赋值号识别 */
                    if (ch == ':')
                    {
                        getch();

                        if (ch == '=')
                        {
                            getch();

                            sym = becomes;
                        }
                        else
                        {
                            error("赋值符号缺少 '=' 符号!");
                        }
                    }
                    else
                    {
                        /* 小于号识别 */
                        if (ch == '<')
                        {
                            getch();

                            if (ch == '=')
                            {
                                sym = leq;
                                getch();
                            }
                            else
                            {
                                sym = lss;
                            }
                        }
                        else
                        {
                            /* 大于号识别 */
                            if (ch == '>')
                            {
                                getch();

                                if (ch == '=')
                                {
                                    getch();
                                    sym = geq;
                                }
                                else
                                {
                                    sym = gtr;
                                }
                            }
                            else
                            {
                                if (ch == '/')
                                {
                                    getch();

                                    /*注释处理 */
                                    if (ch == '/')
                                    {
                                        getch();

                                        cc = ll;
                                        sym = commentsym;

                                        getch();

                                        getsym();

                                        return;
                                    }
                                    else
                                    {
                                        /* C注释处理 */
                                        if (ch == '*')
                                        {
                                            getch();

                                            while (true)
                                            {
                                                while (ch != '*')
                                                {
                                                    getch();

                                                    if (ch == '$')
                                                    {
                                                        sym = term;
                                                        error("缺少注释边界!");

                                                        return;
                                                    }
                                                }

                                                getch();

                                                if (ch == '/')
                                                {
                                                    getch();
                                                    sym = commentsym;

                                                    getsym();

                                                    break;
                                                }
                                            }
                                        }
                                        /* 不等于处理 */
                                        else
                                        {
                                            if (ch == '=')
                                            {
                                                getch();
                                                sym = neql;

                                            }
                                            else
                                            {
                                                sym = slash;
                                            }
                                        }
                                    }
                                }
                                else
                                {
                                    if (ch > 0 && ch < 129)
                                    {
                                        sym = ssym[ch];

                                        if (sym == -1)
                                        {
                                            error("使用不合法标识符!");
                                        }

                                        getch();
                                    }
                                    else
                                    {
                                        error("未知名的字符! ");
                                        getch();
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
        //public static void Main()
        //{
        //    PlxCompile plx = new PlxCompile();
        //    plx.FileOpen("D:\\C#\\procedure.plx");
        //    plx.Compiler();
        //    plx.showCode();
        //    plx.interpret();
        //    Console.WriteLine(plx.lineIndex);
        //}


        /*  语法分析  */
        public enum vartype : int { varConst, varInteger, varLogical, varProc };
        //typedef enum _kind  _kind;

        /* 变量，过程存储数据结构 */
        public struct TABLE
        {
            public string name;
            public vartype kind;
            public int adr;
            public int level;
            public int size;
            public int val;
        };
        TABLE[] table;                          //  存储区       
        int tx;                                 //  table表指针 

        int lev;                                //  静态层次计数 
        int dx;                                 //  局部变量指针 
        public int errornum;                    //  语法错误数目 
        public int errorMax;

        //enter
        void enter(vartype indent) /*  变量入表函数 */
        {
            if (position(id) != 0)
            {
                error("重复定义!");

            }
            else
            {
                tx++;

                table[tx].name = String.Copy(id);
                table[tx].kind = indent;

                switch (indent)