save.c

基于stm32的MP3播放器

#include"FAT.h"

DWORD FirstDirClust;    //第一个目录簇号
DWORD FirstDataSector;	// 数据区的第一个扇区
WORD BytesPerSector;	// 每扇区字节数
DWORD FATsectors;		// 一个FAT表所占扇区数
WORD SectorsPerClust;	// 每簇扇区数
DWORD FirstFATSector;	// 第一个FAT表所在扇区
DWORD FirstDirSector;	// 第一个目录扇区
DWORD RootDirSectors;	// 根目录所在扇区
DWORD RootDirCount;		// 根目录下目录项数
BYTE FAT32_Enable;

BYTE TABLE_READ = 0;
DWORD START_CLUSTER = 0x0ffffff8;	//when the mcu has large ram
BYTE FAT_TABLE[512];				//when the mcu has large ram


BYTE LongNameBuffer[MAX_LONG_NAME_SIZE];
BYTE LongNameFlag = 0;

 					    
//显示一次数据流
void show_data(u8 *p,u16 num)
{			  
	u16 i=0;		  
	printf("TEMP DATA:\n");
	delay_ms(1000);		   
	for(i=0;i<num;i++)printf(" %x",*p++);
	printf("\ndata over\n");  
}	

struct FileInfoStruct FileInfo;//temporarily buffer for file information
 
//FAT初始化，不含SD的初始化，用之前应先调用sd的初始化
unsigned char FAT_Init()//Initialize of FAT  need initialize SD first
{  		   
	struct bootsector710 *bs  = 0;
	struct bpb710        *bpb = 0;
//	struct partsector    *ps  = 0;
	struct partrecord    *pr  = 0;

	BYTE buffer[512];
	DWORD hidsec=0;
	DWORD Capacity;
	
	Capacity = SD_GetCapacity();
	if(Capacity<0xff)return 1;


	if(SD_ReadSingleBlock(0,buffer))return 1;
	bs = (struct bootsector710 *)buffer;

	
	pr = (struct partrecord *)((struct partsector *)buffer)->psPart;//first partition
	hidsec = pr->prStartLBA;//the hidden sectors
	if(hidsec >= Capacity/512)
	{
		hidsec = 0;
	}
	else 
	{
		if(SD_ReadSingleBlock(pr->prStartLBA,buffer))return 1;//read the bpb sector
		bs = (struct bootsector710 *)buffer;
		if(bs->bsJump[0]!=0xE9 && bs->bsJump[0]!=0xEB)
		{
			hidsec = 0;
			if(SD_ReadSingleBlock(0,buffer))return 1;//read the bpb sector
			bs = (struct bootsector710 *)buffer;	
		}
	}

	if(bs->bsJump[0]!=0xE9 && bs->bsJump[0]!=0xEB)//对付没有bootsect的sd卡	//dead with the card which has no bootsect
	{
		return 1;
	}
	bpb = (struct bpb710 *)bs->bsBPB;

	
	if(bpb->bpbFATsecs)//detemine thd FAT type  //do not support FAT12
	{
		FAT32_Enable=0;	//FAT16
		FATsectors		= bpb->bpbFATsecs;//FAT表占用的扇区数 
		FirstDirClust = 2;
	}
	else
	{
		FAT32_Enable=1;	//FAT32
		FATsectors		= bpb->bpbBigFATsecs;//FAT占用的扇区数	//the sectors number occupied by one fat talbe
		FirstDirClust = bpb->bpbRootClust;
	}

	BytesPerSector	= bpb->bpbBytesPerSec;//每扇区字节数
	SectorsPerClust	= (BYTE)bpb->bpbSecPerClust;//每簇扇区数
	FirstFATSector	= bpb->bpbResSectors+hidsec;//第一个FAT表扇区
	RootDirCount	= bpb->bpbRootDirEnts;		//根目录项数
	RootDirSectors	= (RootDirCount*32)>>9;		//根目录占用的扇区数
	FirstDirSector	= FirstFATSector+bpb->bpbFATs*FATsectors;//第一个目录扇区
	FirstDataSector	= FirstDirSector+RootDirSectors;//第一个数据扇区
	return 0; 
}  

//读一个簇中的一个扇区
unsigned char FAT_LoadPartCluster(unsigned long cluster,unsigned part,BYTE * buffer)
{
	DWORD sector;
	sector=(DWORD)FirstDataSector+(DWORD)(cluster-2)*(DWORD)SectorsPerClust;//calculate the actual sector number
	if(SD_ReadSingleBlock(sector+part,buffer))return 1;
	else return 0;
}


//读整个簇
//Read the a cluster
//Not suitable for system which has few data RAM  
unsigned char FAT_LoadCluster(unsigned long cluster,BYTE * buffer)
{
	DWORD sector;
	unsigned char i;
	sector=FirstDataSector+(DWORD)(cluster-2)*(DWORD)SectorsPerClust;//calculate the actual sector number
	for(i=0;i<SectorsPerClust;i++)
	{
		if(SD_ReadSingleBlock(sector+i,buffer+(i<<9)))break;
	}
	if(i==SectorsPerClust)return 0;
	else return 1;
}

//读下一簇簇号
//Return the cluster number of next cluster of file
//Suitable for system which has limited RAM
unsigned long FAT_NextCluster(unsigned long cluster)
{
	BYTE buffer[512];
	DWORD sector;
	DWORD offset;
	if(FAT32_Enable)offset = cluster/128;
	else offset = cluster/256;
	if(cluster<2)return 0x0ffffff8;
	sector=FirstFATSector+offset;//calculate the actual sector
	if(SD_ReadSingleBlock(sector,buffer))return 0x0ffffff8;//read fat table / return 0xfff8 when error occured

	if(FAT32_Enable)
	{
		offset=cluster%128;//find the position
		sector=((unsigned long *)buffer)[offset];	
	}
	else
	{
		offset=cluster%256;//find the position
		sector=((unsigned int *)buffer)[offset];
	}
	return (unsigned long)sector;//return the cluste number
}    

//显示给定路径下的文件
//display the content of a foler , 0 as root directory
unsigned char FAT_DisDir(BYTE *dir)
{
	BYTE *buffer;
	DWORD sector;
	DWORD cluster;
	DWORD tempclust;
	unsigned int cnt;
	unsigned int offset;
	unsigned char i;
	struct direntry *item = 0;
	cluster = FAT_OpenDir(dir);
	if(cluster == 1)return 1;
	if(cluster==0 && FAT32_Enable==0)// root directory
	{
		buffer=malloc(512);//apply memory
		if(buffer==0)return 1;//if failed
		for(cnt=0;cnt<RootDirSectors;cnt++)
		{
			if(SD_ReadSingleBlock(FirstDirSector+cnt,buffer)){free(buffer);return 1;}
			for(offset=0;offset<512;offset+=32)
			{
				item=(struct direntry *)(&buffer[offset]);//pointer convert
				//find a valid item and display it
				if((item->deName[0] != '.') && (item->deName[0] != 0x00) && (item->deName[0] != 0xe5) && (item->deAttributes != 0x0f))
				{
					putchar(0x0d);
					putchar(0x0a);
					for(i=0;i<8;i++)//name
					{
						putchar(item->deName[i]);	
					}
					if((item->deAttributes & 0x10)==0)putchar('.');
					for(i=0;i<3;i++)//extention
					{
						putchar(item->deExtension[i]);
					}
				}
			}
		}
		free(buffer);//release
	}
	else//other folders
	{
		tempclust=cluster;
		while(1)
		{
			sector=(DWORD)FirstDataSector+(DWORD)(tempclust-2)*(DWORD)SectorsPerClust;//calculate the actual sector number
			buffer=malloc(512);//apply memory
			if(buffer==0)return 1;//if failed
			for(cnt=0;cnt<SectorsPerClust;cnt++)
			{
				if(SD_ReadSingleBlock(sector+cnt,buffer)){free(buffer);return 1;}
				for(offset=0;offset<512;offset+=32)
				{
					item=(struct direntry *)(&buffer[offset]);
					if((item->deName[0] != '.') && (item->deName[0] != 0x00) && (item->deName[0] != 0xe5) && (item->deAttributes != 0x0f))
					{
						putchar(0x0d);
						putchar(0x0a);
						for(i=0;i<8;i++)
						{
							putchar(item->deName[i]);	
						}
						if((item->deAttributes & 0x10)==0)putchar('.');
						for(i=0;i<3;i++)
						{
							putchar(item->deExtension[i]);
						}
					}
				}
			}
			free(buffer);//release
			tempclust=FAT_NextCluster(tempclust);//next cluster
			if( tempclust == 0x0ffffff8 )return 1;
			if((FAT32_Enable == 0 && tempclust == 0xffff) || tempclust == 0x0fffffff)break;
		}
	}
	return 0;
}
	 
//在给定目录下查找文件
//Find a item in the directory which specify by the parameter "cluster"
//Return the start cluster number
unsigned int FAT_FindItem(unsigned long cluster, BYTE *name, struct FileInfoStruct *FileInfo)
{
	BYTE *buffer;
	DWORD tempclust;
	DWORD sector;
	unsigned int cnt;
	unsigned int offset;
	unsigned char i;
	struct direntry *item = 0;
	if((cluster==0) && (FAT32_Enable == 0))// root directory
	{
		buffer=malloc(512);//apply memory
		if(buffer==0)return 1;//if failed
		for(cnt=0;cnt<RootDirSectors;cnt++)
		{
			if(SD_ReadSingleBlock(FirstDirSector+cnt,buffer)){free(buffer);return 1;}
			for(offset=0;offset<512;offset+=32)
			{
				item=(struct direntry *)(&buffer[offset]);
				if((item->deName[0] != 0x00) && (item->deName[0] != 0xe5) && (item->deAttributes != 0x0f))
				{
					for(i=0;i<11;i++)
					{
						if(buffer[offset+i]!=name[i])break;
					}
					if(i==11)
					{
						//return the parameter of the item
						FileInfo->StartCluster = item->deStartCluster + (((unsigned long)item->deHighClust)<<16);//don't care
						FileInfo->Size         = item->deFileSize;
						FileInfo->Attr         = item->deAttributes;
						FileInfo->Sector       = FirstDirSector+cnt;
						FileInfo->Offset       = offset;
						free(buffer);
						return 0;
					}
				}
			}
		}
		free(buffer);//release
	}
	else//other folders
	{
		tempclust=cluster;
		while(1)
		{
			sector=(DWORD)FirstDataSector+(DWORD)(tempclust-2)*(DWORD)SectorsPerClust;//calculate the actual sector number
			buffer=malloc(512);//apply memory
			if(buffer==0)return 1;//if failed
			for(cnt=0;cnt<SectorsPerClust;cnt++)
			{
				if(SD_ReadSingleBlock(sector+cnt,buffer)){free(buffer);return 1;}
				for(offset=0;offset<512;offset+=32)
				{
					item=(struct direntry *)(&buffer[offset]);
					if((item->deName[0] != 0x00) && (item->deName[0] != 0xe5) && (item->deAttributes != 0x0f))
					{
						for(i=0;i<11;i++)
						{
							if(buffer[offset+i]!=name[i])break;
						}
						if(i==11)
						{
							FileInfo->StartCluster = item->deStartCluster + (((unsigned long)item->deHighClust)<<16);//don't care
							FileInfo->Size         = item->deFileSize;
							FileInfo->Attr         = item->deAttributes;
							FileInfo->Sector       = sector+cnt;
							FileInfo->Offset       = offset;
							free(buffer);
							return 0;
						}
					}
				}
			}
			free(buffer);//release
			tempclust=FAT_NextCluster(tempclust);//next cluster
			if((FAT32_Enable == 0 && tempclust == 0xffff) || tempclust == 0x0ffffff8 || tempclust == 0x0fffffff)break;
		}
	}
	return 1;
}

  
// find the location with the given path
unsigned long FAT_Open(BYTE * dir)
{
	BYTE name[11];
	BYTE *p=dir;
	BYTE deep=0;
	BYTE i,j;
	DWORD cluster=0;
	if(FAT32_Enable)cluster=FirstDirClust;
	if(*p != '\\')return 1;//invalid path
	while(*p)
	{
		if(*p == '\\')
		{
			deep++;
		}
		p++;
	}
	p=dir;
	for(i=0;i<deep-1;i++)
	{
		p++;
		for(j=0;j<11;j++)name[j]=0x20;
		j=0;
		while(*p != '\\')
		{
			if((*p) >= 'a' && (*p) <= 'z')name[j] = (*p++)-0x20;
			else name[j] = *p++;
			j++;
		}
		if(FAT_FindItem(cluster,name, &FileInfo))return 1;//find the directory
		cluster = FileInfo.StartCluster;
	}
	p++;
	for(j=0;j<11;j++)name[j]=0x20;
	j=0;
	while(*p != '.')//file must have a extention
	{
		if(*p>='a' && *p<='z')name[j]=(*p++)-0x20;
		else name[j]=*p++;
		j++;
	}
	j=8;
	p++;
	while(*p)
	{
		if(*p>='a' && *p<='z')name[j]=(*p++)-0x20;
		else name[j]=*p++;
		j++;
	}
	if(FAT_FindItem(cluster,name, &FileInfo))return 1;//find the file
	cluster = FileInfo.StartCluster;
	return cluster;
}

// find a directory with the given path
unsigned long FAT_OpenDir(BYTE * dir)
{
	BYTE name[11];
	BYTE *p=dir;
	BYTE deep=0;
	BYTE i,j;
	DWORD cluster=0;
	if(FAT32_Enable)cluster = FirstDirClust;
	if(*p != '\\')return 1;//invalid path
	while(*p)
	{
		if(*p == '\\')
		{
			deep++;
		}
		p++;
	}
	p=dir;
	for(i=0;i<deep-1;i++)
	{
		p++;
		for(j=0;j<11;j++)name[j]=0x20;
		j=0;
		while(*p != '\\')
		{
			if((*p) >= 'a' && (*p) <= 'z')name[j] = (*p++)-0x20;
			else name[j] = *p++;
			j++;
		}
		if(FAT_FindItem(cluster,name, &FileInfo))return 1;//find the directory
		cluster = FileInfo.StartCluster;
	}
	p++;
	for(j=0;j<11;j++)name[j]=0x20;
	j=0;
	while(*p)
	{
		if(*p>='a' && *p<='z')name[j]=(*p++)-0x20;
		else name[j]=*p++;
		j++;
	}
	if(j == 0)return cluster;
	if(FAT_FindItem(cluster,name, &FileInfo))return 1;//find the final directory
	cluster = FileInfo.StartCluster;
	return cluster;
}
 /*
unsigned int FAT_Close(unsigned long * p)
{
	*p=1;
	return 0;
}

// Output the data of a file
// size 0 means read all of the file
unsigned char FAT_Read(unsigned long pointer, unsigned long size)
{
	DWORD sector;
	DWORD tempclust=pointer;
	BYTE *buffer;
	unsigned int i=0,j=0;
	sector=(DWORD)FirstDataSector+(DWORD)(tempclust-2)*(DWORD)SectorsPerClust;
	if(size==0)size = FileInfo.Size;//whether need to read all
	putchar(0x0d);
	putchar(0x0a);//new line
	while(size)
	{
		buffer=malloc(512);
		if(SD_ReadSingleBlock(sector+j,buffer)){free(buffer);return 1;}
		if(size<=512)
		{
			for(i=0;i<size;i++)
			{
				putchar(buffer[i]);//output
			}
			free(buffer);
			return 0;//file over
		}
		else
		{
			for(i=0;i<512;i++)
			{
				putchar(buffer[i]);
			}
			j++;
			if(j==SectorsPerClust)
			{
				j=0;
				free(buffer);
				tempclust=FAT_NextCluster(tempclust);//find the next cluster the data was stored
				if((FAT32_Enable == 0 && tempclust == 0xffff) || tempclust == 0x0ffffff8 || tempclust == 0x0fffffff)return 1;//error
				sector=(DWORD)FirstDataSector+(DWORD)(tempclust-2)*(DWORD)SectorsPerClust;//reculculate the sector
			}
			else free(buffer);
			size-=512;
			
		}
	}
	return 0;
}