Hadoop-2.6.0 up the C API for cloud-like functions

Source: Internet
Author: User
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Hadoop-2.6.0 C API to implement cloud-like functions (upload, download, delete, rename)

Test system: CentOS6.6, hadoop-2.6.0

The test is to call the C API under Hadoop to access the HDFS implementation of similar cloud disk upload, download, delete, rename the function, other functions also please the intention to add themselves, nonsense less, start to get to the point.

First we need to be able to access HDFs on the C API on hadoop-2.6.0.

Details can be accessed: http://blog.csdn.net/u013930856/article/details/47660937

Let's start with our cloud disk features:

First we connect to our Hadoop server in the main function and create a user's own folder

int main (int argc, char **argv)
{
Char creatdirname[30];/* Create folders and Paths */
Char dirnamepath[50];
int Create;

Hdfsfs fs = Hdfsconnect ("10.25.100.130", 9000); Connect to a Hadoop server

printf ("Please enter the folder and path you want to create: \ n");
scanf ("%s", creatdirname);


Create = Hdfscreatedirectory (FS, creatdirname);

printf ("Create =%d\n", create);
if (Create = =-1)
{
printf ("Create failed!\n");
Exit (1);
}

while (1)
{
int num;

Hdfschosemenu_function ();
scanf ("%d", &num);
Switch (NUM)
{
Case 1:hdfssendfile_function (FS, creatdirname); HDFs Upload file function
Break
Case 2:hdfsdownfile_function (FS, creatdirname); Download file 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 ");
}
}
}

Uploading files to the server:

void Hdfssendfile_function (Hdfsfs FS, char creatdirname[])//hdfs upload file Function
{
Char sendfilename[30];FileName
Char sendfilepath[50];FilePath
Char Buffer[length];Bufferfile

printf ("Please enter the file name to upload:");
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>>> uploaded file successfully!!! \ n ");
}
}

Download file:

void Hdfsdownfile_function (Hdfsfs FS, char creatdirname[])//download file Function
{
Char downfilename[30];Downfilename
Char downfilepath[50];Downfilepath
Char Buffer[length];Bufferfile

printf ("Please enter the file name to download:");
scanf ("%s", downfilename);

sprintf (Downfilepath, "%s/%s", Creatdirname, Downfilename);
Hdfsfile downopenfile = Hdfsopenfile (FS, Downfilepath, o_rdonly, 0, 0, 0);
if (NULL = = downopenfile)
{
printf ("Open file failed!\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>>> download file successfully!!! \ n ");
}
}
}

To delete a file:

void Hdfsdelete_function (Hdfsfs fs)//hdfsdelete_function
{
int num_delete;
Char delete_hdfsfilepath[50];

printf ("Please enter the name and path of the file you want to delete:");
scanf ("%s", Delete_hdfsfilepath);
Num_delete = Hdfsdelete (FS, Delete_hdfsfilepath, 0);
printf ("Num_delete =%d\n", num_delete);

}

File Rename:

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 ("Please enter the file path and filename to change:"); Middle space separated by Example:/xiaodai 1.jpg
scanf ("%s%s", Hdfsfilepath, Oldhdfsfilename);
printf ("Please enter the changed file name:");
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);
}

This is just a simple implementation of its functionality, if you want to continue to add more and more can, also ask the developer to continue to work

This is just the function core code that implements its function, and its complete code and operating documentation are detailed below:

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

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

Hadoop-2.6.0 up the C API for cloud-like functions

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