Hadoop-2.6.0上调用C的API实现相似云盘的功能

Hadoop-2.6.0上调用C的API实现类似云盘的功能（上传。下载。删除，重命名）

測试系统：CentOS6.6， hadoop-2.6.0

本次測试是调用hadoop下的C的API来訪问HDFS实现类似云盘的上传。下载，删除，重命名的功能，其他功能还请有意者自行加入，废话少说。開始进入正题。

首先我们要能在hadoop-2.6.0上的C的API訪问HDFS

详情能够訪问：http://blog.csdn.net/u013930856/article/details/47660937

以下開始我们的云盘功能：

首先我们在主函数中连接到我们的hadoopserver，并创建一个用户自己的目录

int main(int argc, char **argv) 

{

char CreatDirName[30];
/*创建目录和路径*/

char DirNamePath[50];

int Create;



hdfsFS fs = hdfsConnect("10.25.100.130", 9000);     //连接到hadoopserver



printf("请输入你想创建的目录和路径:\n");

scanf("%s", CreatDirName);





Create = hdfsCreateDirectory(fs, CreatDirName);



printf("Create = %d\n", Create);

if(Create == -1)

{

printf("创建失败!\n");

exit(1);

}



while(1)

{

int num;



HdfsChoseMenu_Function();

scanf("%d", &num);

switch(num)

{

case 1:HdfsSendFile_Function(fs, CreatDirName);     //Hdfs上传文件Function

break;

case 2:HdfsDownFile_Function(fs, CreatDirName);      //下载文件Function

break;

case 3:HdfsDelete_Function(fs);
//HdfsDelete_Function

break;

case 4:HdfsRename_Function(fs);
//HdfsRename_Function

break;

case 0:HdfsQuit_Function(fs);

break;

default:printf("PLease input Error!!!\n");

}

}

}

上传文件到server：

void HdfsSendFile_Function(hdfsFS fs, char CreatDirName[])     //Hdfs上传文件Function

{

char SendFileName[30];
//FileName

char SendFilePath[50];
//FilePath

char buffer[LENGTH];
//BufferFile



printf("请输入要上传的文件名称: ");

scanf("%s", SendFileName);

sprintf(SendFilePath, "%s/%s", CreatDirName, SendFileName);

hdfsFile OpenFileName = hdfsOpenFile(fs, SendFilePath, O_WRONLY|O_CREAT, 0, 0, 0);





FILE *fp = fopen(SendFileName, "r");   





if(NULL == fp)      

{        

printf("File:%s Not Found\n", SendFileName);      

}    

else

{

bzero(buffer, LENGTH);

tSize length = 0;

while((length = fread(buffer, sizeof(char), LENGTH, fp)) > 0)        

{ 

printf("length = %d\n", length);

tSize num_written_bytes = hdfsWrite(fs, OpenFileName, buffer, length);

printf("num_written_bytes = %d\n", num_written_bytes);

if (hdfsFlush(fs, OpenFileName)) 

{

fprintf(stderr, "Failed to 'flush' %s\n", SendFilePath);

exit(-1);

}

bzero(buffer, LENGTH);

}

fclose(fp);  

hdfsCloseFile(fs, OpenFileName);

printf("\n>>>上传文件成功!!!\n\n");

}

}

下载文件：

void HdfsDownFile_Function(hdfsFS fs, char CreatDirName[])      //下载文件Function

{

char DownFileName[30];
//DownFileName

char DownFilePath[50];
//DownFilePath

char buffer[LENGTH];
//BufferFile



printf("请输入要下载的文件名称: ");

scanf("%s", DownFileName);



sprintf(DownFilePath, "%s/%s", CreatDirName, DownFileName);

hdfsFile DownOpenFile = hdfsOpenFile(fs, DownFilePath, O_RDONLY, 0, 0, 0);

if(NULL == DownOpenFile)

{

printf("打开文件失败!\n");

exit(1);

}

else

{

FILE *fp = fopen(DownFileName, "w");    

if(NULL == fp)    

{      

printf("File:\t%s Can Not Open To Write\n", DownFileName);      

exit(1);    

}  

else

{

tSize D_length = 0;


while((D_length = hdfsRead(fs, DownOpenFile, buffer, LENGTH)) > 0)


{

printf("D_length = %d\n", D_length);





if(fwrite(buffer, sizeof(char), D_length, fp) < D_length)      

{        

printf("File:\t%s Write Failed\n", DownFileName);        

break;      

}   

bzero(buffer, LENGTH);

}//sleep(1);

fclose(fp);  

hdfsCloseFile(fs, DownOpenFile);


printf("\n>>>下载文件成功!!!\n\n");


}

}

}

删除文件：

void HdfsDelete_Function(hdfsFS fs)       //HdfsDelete_Function

{

int num_Delete;

char delete_HdfsFilePath[50];



printf("请输入你要删除的文件的名字和路径: ");

scanf("%s", delete_HdfsFilePath);

num_Delete = hdfsDelete(fs, delete_HdfsFilePath, 0);

printf("num_Delete = %d\n", num_Delete);



}

文件重命名：

void HdfsRename_Function(hdfsFS fs) //HdfsRename_Function

{

int num_Rename;

char HdfsFilePath[30] = {0};

char oldHdfsFileName[30] = {0};

char newHdfsFileName[30] = {0};

char oldHdfsFilePath[50] = {0};

char newHdfsFilePath[50] = {0};



printf("请输入要更改的文件路径和文件名称: ");  //中间用空格隔开  example:/xiaodai 1.jpg

scanf("%s%s", HdfsFilePath, oldHdfsFileName);

printf("请输入更改后的文件名称: ");

scanf("%s", newHdfsFileName);



sprintf(oldHdfsFilePath, "%s/%s", HdfsFilePath, oldHdfsFileName);

sprintf(newHdfsFilePath, "%s/%s", HdfsFilePath, newHdfsFileName);



num_Rename = hdfsRename(fs, oldHdfsFilePath, newHdfsFilePath);

printf("num_Rename = %d\n", num_Rename);

}

这仅仅是简单的实现其功能。假设想继续加入其很多其它更能，还请开发人员继续努力

这仅仅是实现其功能的函数核心代码，其完整代码和操作文档详见：

http://download.csdn.net/detail/u013930856/9012061