compile.h

一个用c开发的小型数据库管理系统dbms

		{
            fread(&(from.join[j]),LENGTH,1,file_opened[i].currentfp);
		}
	/*	printf("\n*------------------------------------------------------------*\n");
		fseek(file_opened[i].currentfp,128*LENGTH+2,0);
		for(j=0;j<from.lines*from.fieldlenght;j++){
			fread(&values[0],VALUE_LENGTH,1,file_opened[i].currentfp);
			printf("%20s",values[0].fieldvalue);
			if((j+1)%from.fieldlenght==0) printf("\n|------------------------------------------------------------|\n");
		}
*/
		lll=0;
	}else
	{
		throwerror(13);
	}

	return lll;
}
////////////////////////////////////////////////////
/*
* INSERT Function 插入表元素
*/
///////////////////////////////////////////////////

int insert(char *temp)
{
	int lll=1;
	FILE *fp,*f;
	int i=0,j=0,k=0,m=0,n;
	int len=strlen(temp);
	int err=0;
    char token[20];
	char ch;
//	char *s="OPEN/d/,/w";
//	openrel(s);
	if(len==7){
		throwerror(3);
		return lll;
	}
//	puts(temp);
    i=7;
	j=0;
    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	token[j]='\0';
//	puts(token);
	/////////////if file opened?
    for(n=0;n<openfilenum;n++)
	{
		if(stricmp(token,file_opened[n].filename)==0)
		{
			m=1;
			break;
		}
	}
	if(m)
	{
		if(file_opened[n].station!=1)
		{
			throwerror(14);
			return lll;
		}
		if(file_opened[n].openstyle==0)
		{
			throwerror(15);
			return lll;
		}
		fp=file_opened[n].currentfp;

	}else
	{
		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,"VALUES")==0)
	{
		i++;
		if(i<len)
		{
			if(temp[i]=='(')
			{
				i=i+2;
				for(k=0;k<from.fieldlenght-1;k++)
				{
					if(from.join[k].typesign==2)
					{
						if(temp[i]!='\''){throwerror(16);return lll;}
						i=i+2;
						if(temp[i]=='\'')
						{
							strcpy(values[k].fieldvalue,"null");
							i=i+2;
						}else
						{
							j=0;
	                        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                        token[j]='\0';
//	                        puts(token);
							i++;
							if(temp[i]!='\''){throwerror(1);return lll;}
                            strcpy(values[k].fieldvalue,token);
							i=i+2;
						}
					}else
					{
						if(temp[i]==','){
							
							strcpy(values[k].fieldvalue,"null");
						}
						else{
							j=0;
	                        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                        token[j]='\0';
//	                        puts(token);
					    	strcpy(values[k].fieldvalue,token);
					    	i++;
						}
					}
					if(temp[i]!=',')
					{
						throwerror(1);
						return lll;
					}
					i=i+2;
				}
				if(from.join[from.fieldlenght-1].typesign==2)
				{
					if(temp[i]!='\''){throwerror(16);return lll;}
					i=i+2;
					if(temp[i]=='\'')
					{
						strcpy(values[from.fieldlenght-1].fieldvalue,"null");
						i=i+2;
					}
					else
					{
						j=0;
	                    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                    token[j]='\0';
//	                    puts(token);
				    	i++;
						if(temp[i]!='\''){throwerror(1);return lll;}
                        strcpy(values[from.fieldlenght-1].fieldvalue,token);
						i=i+2;
					}
				}
				else
				{
					if(temp[i]==')')
					{
						strcpy(values[k].fieldvalue,"null");
					}
					else
					{
						j=0;
	                    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                    token[j]='\0';
//	                    puts(token);
					    strcpy(values[k].fieldvalue,token);
					}
				}
				/*///////////
				add file
				///////////*/
				
			}//////if(temp[i]=='(')
		}//////////if(i<len)
		else
		{
			throwerror(1);
		    return lll;
		}
	}///////////if(strcmp(token,"VALUES")==0)
	else////////insert apart
	{
		for(j=0;j<from.fieldlenght;j++)
		{
			strcpy(values[j].fieldvalue,"null");
		}
		if(strcmp(token,"(")!=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);
		to.fieldlenght=1;
		strcpy(to.join[0].wordname,token);
		i++;
		while(i<=len)
		{
			if(temp[i]!=',')break;
			i=i+2;
			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);
			for(k=0;k<to.fieldlenght;k++)
			{
				if(strcmp(token,to.join[k].wordname)==0)
				{
					throwerror(22);
				    return lll;
				}
			}
	    	strcpy(to.join[to.fieldlenght].wordname,token);
            to.fieldlenght++;
	    	i++;
		}
		for(j=0;j<to.fieldlenght;j++)
		{
			for(m=0;m<from.fieldlenght;m++)
			{
				if(strcmp(to.join[j].wordname,from.join[m].wordname)==0)
				{
					to.join[j].locate=m;
			    	break;
				}
			}
		    if(m==from.fieldlenght){throwerror(17);return lll;}
		}
		if(i>=len){throwerror(1);return lll;}
		if(temp[i]!=')'){throwerror(1);return lll;}
		i=i+2;
		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,"VALUES")!=0){throwerror(1);return lll;}
		i++;
        if(i<len)
		{
			if(temp[i]=='(')
			{
				i=i+2;
				for(k=0;k<to.fieldlenght-1;k++)
				{
					m=to.join[k].locate;
					if(from.join[m].typesign==2)
					{
						if(temp[i]!='\''){throwerror(16);return lll;}
						i=i+2;
						if(temp[i]=='\'')
						{
							strcpy(values[k+from.fieldlenght].fieldvalue,"null");
							i=i+2;
						}else
						{
							j=0;
	                        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                        token[j]='\0';
//	                        puts(token);
							i++;
							if(temp[i]!='\''){throwerror(1);return lll;}
                            strcpy(values[k+from.fieldlenght].fieldvalue,token);
							i=i+2;
						}
					}else
					{
						if(temp[i]==','){	
							strcpy(values[k+from.fieldlenght].fieldvalue,"null");
						}
						else{
							j=0;
	                        while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                        token[j]='\0';
//	                        puts(token);
					    	strcpy(values[k+from.fieldlenght].fieldvalue,token);
					    	i++;
						}
					}
					if(temp[i]!=',')
					{
						break;
					}
					i=i+2;
				}
				if(from.join[to.fieldlenght-1].typesign==2)
				{
					if(temp[i]!='\''){throwerror(16);return lll;}
					i=i+2;
					if(temp[i]=='\'')
					{
						strcpy(values[from.fieldlenght-1+from.fieldlenght].fieldvalue,"null");
						i=i+2;
					}
					else
					{
						j=0;
	                    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                    token[j]='\0';
//	                    puts(token);
				    	i++;
						if(temp[i]!='\''){throwerror(1);return lll;}
                        strcpy(values[from.fieldlenght-1+from.fieldlenght].fieldvalue,token);
						i=i+2;
					}
				}
				else
				{
					if(temp[i]==')')
					{
						strcpy(values[k+from.fieldlenght].fieldvalue,"null");
					}
					else
					{
						j=0;
	                    while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	                    token[j]='\0';
//	                    puts(token);
					    strcpy(values[k+from.fieldlenght].fieldvalue,token);
					}
				}
				/*///////////
				add file
				///////////*/
				
			}//////if(temp[i]=='(')
		}//////////if(i<len)
		else
		{
			throwerror(1);
		    return lll;
		}
		for(j=0;j<to.fieldlenght;j++)
		{
			k=to.join[j].locate;
			strcpy(values[k].fieldvalue,values[j+from.fieldlenght].fieldvalue);
		}
	}
	///////////////////////////write file
	f=fopen("temp$","wb+");
	rewind(fp);
    fputc(fgetc(fp),f);
	fputc(fgetc(fp)+1,f);
	ch=fgetc(fp);
	while(ch!=EOF)
	{
		fputc(ch,f);
		ch=fgetc(fp);
	}
	fclose(f);
	fclose(fp);
	fp=fopen(file_opened[n].filename,"wb+");
	f=fopen("temp$","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+");
	fp=file_opened[n].currentfp;
	for(i=0;i<from.fieldlenght;i++)
	{
		fwrite(&values[i],sizeof(struct value),1,file_opened[n].currentfp);
	}
	fclose(file_opened[n].currentfp);
	file_opened[n].currentfp=fopen(file_opened[n].filename,"ab+");
	for(i=0;i<from.fieldlenght;i++)
	{
		lll=condition(from.join[i].key,i,file_opened[n].currentfp);
		if(lll) break;
	}
	if(lll)throwerror(26);
	return lll;
}
////////////////////////////////////////////////////
/*
* DELETE Function 删除表元祖
*/
///////////////////////////////////////////////////
int deleterel(char *temp)
{
	int lll=1;
	FILE *fp,*f;
	int i=0,j=0,k=0,m=0,err=1;
	int len=strlen(temp);
    char token[20];
	char ch;
	int seeklocation1=-1;

    seeklocation1=seeklocation;

//	printf("%d\n",seeklocation);
///////////////////////////////////////////if opened
    for(i=0;i<openfilenum;i++)
	{
		if(file_opened[i].station)
		{
			if(!file_opened[i].openstyle){throwerror(15);return lll;}
			fp=file_opened[i].currentfp;
			err=0;
		    break;
		}
	}

	if(err){throwerror(10);return lll;}
//////////////////////////////////////////
	if(len==7){		
		if(seeklocation1==-1)
		{
			throwerror(18);
			return lll;
		}else
		{
			
			/////////////////////
			
	/////////////////////
            f=fopen("temp$","wb+");
	        rewind(fp);
            fputc(fgetc(fp),f);
	        fputc(fgetc(fp)-1,f);
        	for(j=0;j<128;j++)
			{
				fread(&(from.join[j]),LENGTH,1,fp);
				fwrite(&(from.join[j]),LENGTH,1,f);
			}

            for(j=0;j<(seeklocation1-1)*from.fieldlenght;j++)
			{
				fread(&values[0],VALUE_LENGTH,1,fp);
				fwrite(&values[0],VALUE_LENGTH,1,f);
			}

			if(seeklocation1<from.lines)
			{
				fseek(fp,from.fieldlenght*VALUE_LENGTH,1);
				for(j=0;j<(from.lines-seeklocation1)*from.fieldlenght;j++)
				{
					fread(&values[0],VALUE_LENGTH,1,fp);
				    fwrite(&values[0],VALUE_LENGTH,1,f);
				}
			}

        	fclose(f);
        	fclose(fp);
        	fp=fopen(file_opened[i].filename,"wb+");
        	f=fopen("temp$","r");
        	ch=fgetc(f);
            while(ch!=EOF)
			{
        		fputc(ch,fp);
        		ch=fgetc(f);
			}
        	fclose(f);
        	fclose(fp);
            file_opened[i].currentfp=fopen(file_opened[i].filename,"ab+");
			seeklocation=-1;
			remove("temp$");
			lll=0;
		}
	}
	else
	{
		i=7;
		j=0;
		while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
    	token[j]='\0';
 //   	puts(token);
		if(stricmp(token,"where")!=0){throwerror(1);return lll;}
		////////////////////////////////////////////////////////
		i++;
		if(i>=len){throwerror(21);return lll;}
        j=0;
		while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
    	token[j]='\0';
//    	puts(token);
		m=0;
		for(k=0;k<from.fieldlenght;k++)
		{
			if(strcmp(token,from.join[k].wordname)==0)
			{
				m=1;
				break;
			}
		}
		if(!m){throwerror(17);return lll;}
        
		///////////////////////////////////////////////////////
        i++;
		if(i>=len){throwerror(1);return lll;}
		if(temp[i]!='='){	throwerror(1);return lll;}
		i=i+2;
        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);
		////////////////////
		/*   add if float/int         */
		////////////////////
        
		m=0;
		i=0;
		while(i<from.lines)
		{
			rewind(fp);
			fseek(fp,2+128*LENGTH,0);
			fseek(fp,(k+i*from.fieldlenght)*VALUE_LENGTH,1);
			fread(&values[0],VALUE_LENGTH,1,fp);
			if(strcmp(token,values[0].fieldvalue)==0) 
			{
				m=1;
				seeklocation=i+1;
		        strcpy(temp,"DELETE/");
		        deleterel(temp);
				from.lines--;
			}else
			{
				i++;
			}
		}
		if(!m){throwerror(19);return lll;}
		lll=0;
	}
	return lll;
}
////////////////////////////////////////////////////
/*
* PROJECT Function 投影表函数
*/
///////////////////////////////////////////////////
int project(char *temp)
{
	int lll=1;
	FILE *fp,*f;
	int i=0,j=0,k=0,m=0,err=1;
	int len=strlen(temp);
    char token[20];
    if(len==8){
		throwerror(20);
		return lll;
	}
	//////////////////file1
	i=8;
	j=0;
	while(i<=len&&temp[i]!='/'){token[j]=temp[i];i++;j++;}
	token[j]='\0';
//	puts(token);
	err=1;
	for(k=0;k<openfilenum;k++)
	{