compile.h

一个用c开发的小型数据库管理系统dbms

		tmp.fieldlenght=fgetc(f1);
		tmp.lines=fgetc(f1);
		for(j=0;j<tmp.fieldlenght;j++)
		{
            fread(&(tmp.join[j]),LENGTH,1,f1);
		}
        for(j=0;j<from1.fieldlenght;j++)
		{
			for(m=0;m<tmp.fieldlenght;m++)
			{
		//		puts(to.join[j].wordname);
			    if(strcmp(from1.join[j].wordname,tmp.join[m].wordname)==0)
				{
					from1.join[j].locate=m;
			    	break;
				}
			}
		    if(m==tmp.fieldlenght){throwerror(17);return lll;}
		}
		rewind(f2);
		l=tmp.fieldlenght;
		tmp.fieldlenght=fgetc(f2);
		tmp.lines=fgetc(f2);
		for(j=0;j<tmp.fieldlenght;j++)
		{
            fread(&(tmp.join[j]),LENGTH,1,f2);
		}
        for(j=0;j<from1.fieldlenght;j++)
		{
			for(m=0;m<tmp.fieldlenght;m++)
			{
		//		puts(to.join[j].wordname);
			    if(strcmp(to.join[j].wordname,tmp.join[m].wordname)==0)
				{
					to.join[j].locate=m+l;
			    	break;
				}
			}
		    if(m==tmp.fieldlenght){throwerror(17);return lll;}
		}
		///////////////////////////////////////////
        if(i>=len){throwerror(1);return lll;}
        j=0;
        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	    token[j]='\0';
//	    puts(token);
		if(stricmp(token,"to")!=0){throwerror(1);return lll;}
		i++;
		if(i>=len){throwerror(1);return lll;}
        j=0;
        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	    token[j]='\0';
//	    puts(token);
		if((fp=fopen(token,"r"))!=NULL)
		{
			throwerror(4);
		    fclose(fp);
	    	return lll;
		}
        f=fopen("temp$","r");
        fp=fopen(token,"wb+");
		ch=fgetc(f);
        while(ch!=EOF)
		{
        	fputc(ch,fp);
        	ch=fgetc(f);
		}
		fclose(f);
		remove("temp$");
		fclose(fp);
		/////////////////////////////////////////////
		strcpy(temp,"OPEN/");
		strcat(temp,token);
		strcat(temp,"/,/w/");
		openrel(temp);
		fclose(fp);
		fp=fopen(token,"ab+");
		rewind(fp);
		tmp.fieldlenght=fgetc(fp);
		tmp.lines=fgetc(fp);
		for(i=0;i<tmp.fieldlenght;i++)
		{
			fread(&tmp.join[i],LENGTH,1,fp);
		}
		i=0;
		while(i<tmp.lines)
		{
			for(j=0;j<from1.fieldlenght;j++)
			{
				///////////////////////////////////data1
				k=from1.join[j].locate;
		    	rewind(fp);
		    	fseek(fp,2+128*LENGTH,0);
		    	fseek(fp,(k+i*tmp.fieldlenght)*VALUE_LENGTH,1);
				fread(&values[0],VALUE_LENGTH,1,fp);
				///////////////////////////////////data2
				k=to.join[j].locate;
		    	rewind(fp);
		    	fseek(fp,2+128*LENGTH,0);
		    	fseek(fp,(k+i*tmp.fieldlenght)*VALUE_LENGTH,1);
				fread(&values[1],VALUE_LENGTH,1,fp);
				///////////////////////////////////
				m=0;
				if(strcmp(values[0].fieldvalue,values[1].fieldvalue)!=0)
				{
					seeklocation=i+1;
		            strcpy(temp,"DELETE/");
		            deleterel(temp);
					m=1;
					tmp.lines--;
					break;
				}
			}
			if(!m) i++;
		}
		///////////////////////////////////
		fclose(fp);
		fclose(f);
		f=fopen("temp$","wb+");
		fp=fopen(token,"r");
		rewind(fp);
        fieldnum=fgetc(fp);
		line=fgetc(fp);
		from.fieldlenght=fieldnum;
		from.lines=line;
		for(i=0;i<from.fieldlenght-1;i++)
		{
			for(j=i+1;j<from.fieldlenght;j++)
			{
				if(strcmp(from.join[i].wordname,from.join[j].wordname)==0)
				{
					from.join[j].locate=-1;
					fieldnum--;
				}
			}
		}
		fputc(fieldnum,f);
		fputc(line,f);
        for(i=0;i<from.fieldlenght;i++)
		{
			if(from.join[i].locate!=-1)
			{
				fwrite(&(from.join[i]),LENGTH,1,f);
			}
		}
		for(i=fieldnum;i<128;i++)
		{
			fwrite(&(from.join[i]),LENGTH,1,f);
		}
		rewind(fp);
		fseek(fp,2+128*LENGTH,0);
		for(i=0;i<from.lines;i++)
		{
			for(j=0;j<from.fieldlenght;j++)
			{
				fread(&values[0],VALUE_LENGTH,1,fp);
				if(from.join[j].locate!=-1)
				{
					fwrite(&values[0],VALUE_LENGTH,1,f);
				}
			}
		}
		fclose(f);
		fclose(fp);
		remove(token);
		rename("temp$",token);
		fp=fopen(token,"ab+");
		rewind(fp);
		from.fieldlenght=fgetc(fp);
		from.lines=fgetc(fp);
		for(i=0;i<from.fieldlenght;i++)
		{
			fread(&from.join[i],LENGTH,1,fp);
		}
		file_opened[openfilenum-1].currentfp=fp;
		///////////////////////////////////
		lll=0;
	}
	else
	{
		throwerror(1);
		return lll;
	}
    
	///////////////////////////////////////////////file end
	///////////////////////////////////////////////////////
	return lll;
}
////////////////////////////////////////////////////
/*
* ALTER Function 添加字段函数
*/
///////////////////////////////////////////////////
int alter(char *temp)
{
	int lll=1;
	FILE *fp,*f;
	int i=0,j=0,k=0,m=0,l,line,fieldnum,n;
	int len=strlen(temp);
	int err=0;
    char token[20];
	char ch;
	if(len==6){
		throwerror(3);
		return lll;
	}
//	puts(temp);
    i=6;
	j=0;
    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	token[j]='\0';
//	puts(token);
    err=1;
	for(n=0;n<openfilenum;n++)
	{
		if(stricmp(token,file_opened[n].filename)==0)
		{
			if(file_opened[n].station)
			{
				if(!file_opened[n].openstyle){throwerror(15);return lll;}
				fp=file_opened[n].currentfp;
				err=0;
			    break;	
			}else
			{
				throwerror(14);
	            return lll;
			}	
		}
	}
	if(err){throwerror(13);return lll;}
	///////////////////////////////////////////
	i++;
	if(i>=len){throwerror(1);return lll;}
    j=0;
    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	token[j]='\0';
//	puts(token);
	if(stricmp(token,"add")!=0){throwerror(1);return lll;}
        i++;
		if(temp[i]!='('){throwerror(1);return lll;}
		i=i+2;
        j=0;
		rewind(fp);
		fieldnum=fgetc(fp);
		line=fgetc(fp);
		for(k=0;k<fieldnum;k++) fread(&rel[k],LENGTH,1,fp);
        while(i<=len)
		{
			j=0;
			l=i;
            while(l<=len&&temp[l]!='/'){
				token[j]=temp[l];
				j++;
				l++;
			}
			token[j]='\0';
            for(m=0;m<k;m++)
			{
				if(strcmp(token,rel[m].wordname)==0)
				{
					throwerror(5);
					return lll;
				}
			}
			strcpy(rel[k].wordname,token);
			rel[k].key=0;
//				puts(rel[k].wordname);
				///////////////////////////
			l++;
			j=0;
            while(l<=len&&temp[l]!='/'){
				token[j]=temp[l];
				j++;
				l++;
			}
			token[j]='\0';
			strlwr(token);
//			puts(token);
			if(strcmp(token,"int")==0)
			{
				rel[k].typesign=0;
				rel[k].length=16;
				l++;
			}else if(strcmp(token,"float")==0){
                rel[k].typesign=1;
				rel[k].length=16;
				l++;
			}else if(strcmp(token,"char")==0){
                rel[k].typesign=2;
				l++;
				if(temp[l]!='('){throwerror(1);return lll;}
				else
				{
					l++;
					l++;
                    j=0;
                    while(l<=len&&temp[l]!='/'){
					        token[j]=temp[l];
				           	j++;
				        	l++;
					}
				    token[j]='\0';
                    rel[k].length=atoi(token);
//					  printf("%d\n",rel[k].length);
				   l++;
				 }
				if(temp[l]!=')'){throwerror(1);return lll;}
				else{l++;l++;}
                }else{throwerror(1);return lll;}
				if(temp[l]=='P'||temp[l]=='N'||temp[l]=='U'){
					j=0;
					while(l<=len&&temp[l]!='/'){
					token[j]=temp[l];
					j++;
					l++;
					}
				    token[j]='\0';
				    strlwr(token);
//				    puts(token);
                    if(strcmp(token,"primarykey")==0)
					{
						rel[k].key=1;
						l++;
					}
					if(strcmp(token,"notnull")==0)
					{
						rel[k].key=2;
						l++;
					}
					if(strcmp(token,"unique")==0)
					{
						rel[k].key=3;
						l++;
					}
					if(strcmp(token,"notnullunique")==0)
					{
						rel[k].key=4;
						l++;
					}
				}
				if(temp[l]==')')
				{
					l++;
					l++;
					k++;
					i=l;
					break;
				}else if(temp[l]==',')
				{
					k++;
				    i=l;
					i++;
					i++;
				    continue;
				}else{
					throwerror(1);return lll;
				}
				///////////////////////////
			}
			 
			if((f=fopen("temp$","wb+"))!=NULL)
			{ 
				fputc(k,f);
				from.fieldlenght=k;

			    fputc(line,f);
				fseek(fp,2+128*LENGTH,0);
			    for(j=0;j<k;j++)
				{
					strcpy(from.join[j].wordname,rel[j].wordname);
					rel[j].locate=j+1;
				}
                for(j=0;j<128;j++)
				fwrite(&rel[j],LENGTH,1,f);
                for(i=0;i<line;i++)
				{
					for(j=0;j<k-1;j++)
					{
						fread(&values[0],VALUE_LENGTH,1,fp);
					    fwrite(&values[0],VALUE_LENGTH,1,f);
					}
					strcpy(values[0].fieldvalue,"null");
					fwrite(&values[0],VALUE_LENGTH,1,f);
				}
		        fclose(f);
            	fclose(fp);
            	fp=fopen(file_opened[n].filename,"wb+");
            	f=fopen("temp$","r");
            	ch=fgetc(f);
                while(ch!=EOF)
				{
        	    	fputc(ch,fp);
             		ch=fgetc(f);
				}
             	fclose(f);
				remove("temp$");
            	fclose(fp);
                file_opened[n].currentfp=fopen(file_opened[n].filename,"ab+");

			    lll=0;
				}else
				{
				     throwerror(2);
				}
	///////////////////////////////////////////
	return lll;
}
////////////////////////////////////////////////////
/*
* SEEK Function 按行号查找数据函数
*/
///////////////////////////////////////////////////
int seek(char *temp)
{
	int lll=1;
	FILE *fp;
	int i=0,j=0,m=0,err=1;
	int len=strlen(temp);
    char token[20];
	int seeklocation1;

	seeklocation=-1;

	if(len==5){
		throwerror(1);
		return lll;
	}
	puts(temp);
	i=5;
	j=0;
    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	token[j]='\0';
//	puts(token);
	for(i=0;i<j;i++)
	{
		if(!isNum(token[i]))
		{
			throwerror(1);
			return lll;
		}
	}
	m=atoi(token);
    for(i=0;i<openfilenum;i++)
	{
		if(file_opened[i].station)
		{
			fp=file_opened[i].currentfp;
			err=0;
			break;
		}
	}
	if(err){throwerror(10);return lll;}
	if(m>from.lines)
	{
		m=from.lines;
		printf("\nExceeded to limit!\n");
	}
	if(m<1)
	{
		m=1;
		printf("\nExceeded to limit!\n");
	}
		for(i=0;i<from.fieldlenght;i++)
		{
			printf("%20s",from.join[i].wordname);
		}
		printf("\n*");
        for(j=0;j<from.fieldlenght;j++) printf("--------------------");
	    printf("*\n");
		seeklocation1=128*LENGTH+2+from.fieldlenght*(m-1)*VALUE_LENGTH;
		seeklocation=m;
		fseek(fp,seeklocation1,0);
		for(i=0;i<from.fieldlenght;i++){
			fread(&values[0],VALUE_LENGTH,1,fp);
		    printf("%20s",values[0].fieldvalue);
		}
        printf("\n|");
        for(j=0;j<from.fieldlenght;j++) printf("--------------------");
	    printf("|\n");	    
		fseek(fp,seeklocation1,0);
		lll=0;
	return lll;
}
////////////////////////////////////////////////////
/*
* Condition Function 根据表属性判断实体完整性函数
*/
///////////////////////////////////////////////////

int condition(int con,int id,FILE *f)
{
	int lll=0;
	int i,j,k,line,num;
	char *temp="DELETE/";
	rewind(f);
	num=fgetc(f);
	line=fgetc(f);
	if(con==1)
	{
		k=0;
		i=0;
		while(i<line-1)
		{
			rewind(f);
			fseek(f,2+128*LENGTH,0);
			fseek(f,(id+i*num)*VALUE_LENGTH,1);
			fread(&values[0],VALUE_LENGTH,1,f);
			j=i+1;
			while(j<line)
			{
				rewind(f);
				fseek(f,2+128*LENGTH,0);
			    fseek(f,(id+j*num)*VALUE_LENGTH,1);
			    fread(&values[1],VALUE_LENGTH,1,f);
				if(strcmp(values[0].fieldvalue,values[1].fieldvalue)==0)
				{
					seeklocation=j+1;
					deleterel(temp);
					line--;
					printf("\n%s is key,not allow duplicate!\n",from.join[id].wordname);
					k=1;
				}
				else
				{
					j++;
				}
			}
			i++;
		}
		i=0;
		while(i<line)
		{
			rewind(f);
			fseek(f,2+128*LENGTH,0);
			fseek(f,(id+i*num)*VALUE_LENGTH,1);
			fread(&values[0],VALUE_LENGTH,1,f);
			if(strcmp(values[0].fieldvalue,"null")==0)
			{
				seeklocation=i+1;
				deleterel(temp);
				line--;
				printf("\n%s is key,not allow null!\n",from.join[id].wordname);
				k=1;
			}
			else
			{
				i++;
			}
		}
		if(k)
		{
			lll=1;
		}
	}
	else if(con==2)
	{