y.tab.c

一个c语言开发的小型的dbms系统

		sqlnum++;
		ss=sql[sqlnum];
	}
	aword[awordnum]='\0';
}



yylex()
{
	char	ss;
	int	is_a_token;
	char	theword[256];	/*用于分解出输入行的一个单词*/
	while (sql[sqlnum]==' ')
		sqlnum++;
	ss=sql[sqlnum];
	if (ss=='\0') return(0);
	if (is_legal(ss)==0)	
	{	/*主要识别标点和运算符*/		
		sqlnum++;
		return(ss);
	}
	else	
	{	readaword(theword);
		 	/*主要识别保留字*/
		if (is_a_token=is_token(theword))	return(is_a_token);
			/*识别数字和标识符*/
		yylval.yych=(char *)malloc(strlen(theword)+1); 
		strcpy(yylval.yych,theword); 		
		if (is_number(theword)) 		return(NUMBER);
		if (is_identifier(theword))  	return(IDENTIFIER);
	}/*else*/	
	return(0);
}

void yyerror(char *s)
{
	printf("%s\n",s);
}

void check_sql()
{	
	int length=strlen(sql);
	if  (sql[length-1]!=';') 	/*如果用户没有在最后以'；'结束，就给他们加上一个'；'*/
		{		/*这样才可以把QUIT也加入词法分析中*/
		sql[length]=';';	/*这样可以使用户不用在QUIT后面也加入'；'就能被接受。*/
		sql[length+1]='\0';
		}
}


main()

{	extern	int yyparse();
	FILE	*fp;
	char    buf[256];
	int		seek_beg=0;
	char	*result;
	while(1)

	{

		read_dic(dic.tab, &(dic.tab_num), dic.col, &(dic.col_num));	/*读出字典表信息*/

		printf("\nSQL>");

		sqlnum=0;		/*每次将指向sql的指针返回到起点*/

		finish_flag=0;	/*将结束控制变量初始化*/

		gets(sql);	/*获取输入行*/

		if(sql[0]=='@')
		{
			strncpy(buf,sql+1,strlen(sql)-1);
			buf[strlen(sql)-1]='\0';
			fp=fopen(buf,"rb");
			if(fp==NULL)
			{
				printf("Can't open file %s\n",buf);
				continue;
			}
			while(!feof(fp))
			{
//				result=fseek(fp,';',seek_beg);
//				seek_beg=result;
				fgets(sql,1024,fp);

				printf("%s\n",sql);//asdfasadfasdf

				result=strchr(sql,';');
				strncpy(buf,sql,result-sql);
				buf[result-sql]='\0';
				strcpy(sql,buf);
				printf("%s\n",sql);
				check_sql(sql);	/*对输入行后面的'；'做处理*/
				if (yyparse()==0)
					printf("The command has been completed successfully!\n");
				if (finish_flag==1)	break;		/*如果用户输入了quit那么将结束程序*/
						read_dic(dic.tab, &(dic.tab_num), dic.col, &(dic.col_num));	/*读出字典表信息*/
				printf("\nSQL>");
				sqlnum=0;		/*每次将指向sql的指针返回到起点*/
				finish_flag=0;	/*将结束控制变量初始化*/
			}

		}
		else
		{
			check_sql(sql);	/*对输入行后面的'；'做处理*/
			if (yyparse()==0)
				printf("The command has been completed successfully!\n");
			if (finish_flag==1)	break;		/*如果用户输入了quit那么将结束程序*/
		}
	}			
}

#line 525 "no_help.c"
/* allocate initial stack or double stack size, up to YYMAXDEPTH */
static int yygrowstack()
{
    int newsize, i;
    short *newss;
    YYSTYPE *newvs;

    if ((newsize = yystacksize) == 0)
        newsize = YYINITSTACKSIZE;
    else if (newsize >= YYMAXDEPTH)
        return -1;
    else if ((newsize *= 2) > YYMAXDEPTH)
        newsize = YYMAXDEPTH;
    i = yyssp - yyss;
    newss = yyss ? (short *)realloc(yyss, newsize * sizeof *newss) :
      (short *)malloc(newsize * sizeof *newss);
    if (newss == NULL)
        return -1;
    yyss = newss;
    yyssp = newss + i;
    newvs = yyvs ? (YYSTYPE *)realloc(yyvs, newsize * sizeof *newvs) :
      (YYSTYPE *)malloc(newsize * sizeof *newvs);
    if (newvs == NULL)
        return -1;
    yyvs = newvs;
    yyvsp = newvs + i;
    yystacksize = newsize;
    yysslim = yyss + newsize - 1;
    return 0;
}

#define YYABORT goto yyabort
#define YYREJECT goto yyabort
#define YYACCEPT goto yyaccept
#define YYERROR goto yyerrlab

#ifndef YYPARSE_PARAM
#if defined(__cplusplus) || __STDC__
#define YYPARSE_PARAM_ARG void
#define YYPARSE_PARAM_DECL
#else	/* ! ANSI-C/C++ */
#define YYPARSE_PARAM_ARG
#define YYPARSE_PARAM_DECL
#endif	/* ANSI-C/C++ */
#else	/* YYPARSE_PARAM */
#ifndef YYPARSE_PARAM_TYPE
#define YYPARSE_PARAM_TYPE void *
#endif
#if defined(__cplusplus) || __STDC__
#define YYPARSE_PARAM_ARG YYPARSE_PARAM_TYPE YYPARSE_PARAM
#define YYPARSE_PARAM_DECL
#else	/* ! ANSI-C/C++ */
#define YYPARSE_PARAM_ARG YYPARSE_PARAM
#define YYPARSE_PARAM_DECL YYPARSE_PARAM_TYPE YYPARSE_PARAM;
#endif	/* ANSI-C/C++ */
#endif	/* ! YYPARSE_PARAM */

int
yyparse (YYPARSE_PARAM_ARG)
    YYPARSE_PARAM_DECL
{
    register int yym, yyn, yystate;
#if YYDEBUG
    register const char *yys;

    if ((yys = getenv("YYDEBUG")))
    {
        yyn = *yys;
        if (yyn >= '0' && yyn <= '9')
            yydebug = yyn - '0';
    }
#endif

    yynerrs = 0;
    yyerrflag = 0;
    yychar = (-1);

    if (yyss == NULL && yygrowstack()) goto yyoverflow;
    yyssp = yyss;
    yyvsp = yyvs;
    *yyssp = yystate = 0;

yyloop:
    if ((yyn = yydefred[yystate])) goto yyreduce;
    if (yychar < 0)
    {
        if ((yychar = yylex()) < 0) yychar = 0;
#if YYDEBUG
        if (yydebug)
        {
            yys = 0;
            if (yychar <= YYMAXTOKEN) yys = yyname[yychar];
            if (!yys) yys = "illegal-symbol";
            printf("%sdebug: state %d, reading %d (%s)\n",
                    YYPREFIX, yystate, yychar, yys);
        }
#endif
    }
    if ((yyn = yysindex[yystate]) && (yyn += yychar) >= 0 &&
            yyn <= YYTABLESIZE && yycheck[yyn] == yychar)
    {
#if YYDEBUG
        if (yydebug)
            printf("%sdebug: state %d, shifting to state %d\n",
                    YYPREFIX, yystate, yytable[yyn]);
#endif
        if (yyssp >= yysslim && yygrowstack())
        {
            goto yyoverflow;
        }
        *++yyssp = yystate = yytable[yyn];
        *++yyvsp = yylval;
        yychar = (-1);
        if (yyerrflag > 0)  --yyerrflag;
        goto yyloop;
    }
    if ((yyn = yyrindex[yystate]) && (yyn += yychar) >= 0 &&
            yyn <= YYTABLESIZE && yycheck[yyn] == yychar)
    {
        yyn = yytable[yyn];
        goto yyreduce;
    }
    if (yyerrflag) goto yyinrecovery;
#if defined(lint) || defined(__GNUC__)
    goto yynewerror;
#endif
yynewerror:
	printf("error22:XXXXXXXX\n");//???????
    yyerror("zhao:syntax error\n");
#if defined(lint) || defined(__GNUC__)
    goto yyerrlab;
#endif
yyerrlab:
    ++yynerrs;
yyinrecovery:
    if (yyerrflag < 3)
    {
        yyerrflag = 3;
        for (;;)
        {
            if ((yyn = yysindex[*yyssp]) && (yyn += YYERRCODE) >= 0 &&
                    yyn <= YYTABLESIZE && yycheck[yyn] == YYERRCODE)
            {
#if YYDEBUG
                if (yydebug)
                    printf("%sdebug: state %d, error recovery shifting\
 to state %d\n", YYPREFIX, *yyssp, yytable[yyn]);
#endif
                if (yyssp >= yysslim && yygrowstack())
                {
                    goto yyoverflow;
                }
                *++yyssp = yystate = yytable[yyn];
                *++yyvsp = yylval;
                goto yyloop;
            }
            else
            {
#if YYDEBUG
                if (yydebug)
                    printf("%sdebug: error recovery discarding state %d\n",
                            YYPREFIX, *yyssp);
#endif
                if (yyssp <= yyss) goto yyabort;
                --yyssp;
                --yyvsp;
            }
        }
    }
    else
    {
        if (yychar == 0) goto yyabort;
#if YYDEBUG
        if (yydebug)
        {
            yys = 0;
            if (yychar <= YYMAXTOKEN) yys = yyname[yychar];
            if (!yys) yys = "illegal-symbol";
            printf("%sdebug: state %d, error recovery discards token %d (%s)\n",
                    YYPREFIX, yystate, yychar, yys);
        }
#endif
        yychar = (-1);
        goto yyloop;
    }
yyreduce:
#if YYDEBUG
    if (yydebug)
        printf("%sdebug: state %d, reducing by rule %d (%s)\n",
                YYPREFIX, yystate, yyn, yyrule[yyn]);
#endif
    yym = yylen[yyn];
    yyval = yyvsp[1-yym];
    switch (yyn)
    {
case 1:
#line 81 "no_help.y"
{/*调用select对应的函数*/
		error_var=select_errorcheck(&dic,yyvsp[0].ss_var);
		if (strcmp(error_var,"")!=0) 
			{yyerror(error_var);
			return(1);
			}
		selectpro(yyvsp[0].ss_var,&dic);
		/*selectexe($1);*/
		}
break;
case 2:
#line 91 "no_help.y"
{/*调用createexe对应的函数*/
		error_var=create_errorcheck(&dic,yyvsp[0].cs_var);
		if (strcmp(error_var,"")!=0) 
			{yyerror(error_var);
			return(1);
			}
		createpro(yyvsp[0].cs_var,&dic);
		/*createexe($1);*/
		}
break;
case 3:
#line 101 "no_help.y"
{/*调用insertexe对应的函数*/
		error_var=insert_errorcheck(&dic,yyvsp[0].is_var);
		if (strcmp(error_var,"")!=0) 
			{yyerror(error_var);
			return(1);
			}
		insertpro(yyvsp[0].is_var,&dic);
		/*insertexe($1);*/
		}
break;
case 4:
#line 111 "no_help.y"
{/*调用deleteexe对应的函数*/
		error_var=delete_errorcheck(&dic,yyvsp[0].ds_var);
		if (strcmp(error_var,"")!=0) 
			{yyerror(error_var);
			return(1);
			}
		deletepro(yyvsp[0].ds_var,&dic);
		/*deleteexe($1);*/
		}
break;
case 5:
#line 121 "no_help.y"
{
		/*conditionsexe($1);*/
		}
break;
case 6:
#line 125 "no_help.y"
{
		finish_flag=1;	/*表示应当退出了*/
		}
break;
case 8:
#line 133 "no_help.y"
{
		yyval.ss_var=(_selectstruct_type *)malloc(sizeof(_selectstruct_type));
		yyval.ss_var->sf=yyvsp[-3].sf_var;
		yyval.ss_var->st=yyvsp[-1].st_var;
		yyval.ss_var->cons=NULL;
		}
break;
case 9:
#line 140 "no_help.y"
{
		yyval.ss_var=(_selectstruct_type *)malloc(sizeof(_selectstruct_type));
		yyval.ss_var->sf=yyvsp[-5].sf_var;
		yyval.ss_var->st=yyvsp[-3].st_var;
		yyval.ss_var->cons=yyvsp[-1].cons_var;
		}
break;
case 10:
#line 148 "no_help.y"
{
		yyval.sf_var=yyvsp[0].sf_var;
		}
break;
case 11:
#line 152 "no_help.y"
{
		yyval.sf_var=(_selectedfields_type *)malloc(sizeof(_selectedfields_type));
		yyval.sf_var->table=NULL;
		yyval.sf_var->field="*";
		yyval.sf_var->next_sf=NULL;
		}
break;
case 12:
#line 160 "no_help.y"
{