c libhdfs書き込みデータを用いてblocksizeを構成する


 libhdfs   hdfswrite          namenode  ip   
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "hdfs.h" 

int main(int argc, char **argv) {

    if (argc != 4) {
        fprintf(stderr, "Usage: hdfs_write <filename> <filesize> <buffersize>
"); exit(-1); } hdfsFS fs = hdfsConnect("192.168.1.1", 8020); if (!fs) { fprintf(stderr, "Oops! Failed to connect to hdfs!
"); exit(-1); } const char* writeFileName = argv[1]; tSize fileTotalSize = strtoul(argv[2], NULL, 10); tSize bufferSize = strtoul(argv[3], NULL, 10); hdfsFile writeFile = hdfsOpenFile(fs, writeFileName, O_WRONLY, bufferSize, 0, 0); if (!writeFile) { fprintf(stderr, "Failed to open %s for writing!
", writeFileName); exit(-2); } // data to be written to the file char* buffer = malloc(sizeof(char) * bufferSize); if(buffer == NULL) { return -2; } int i = 0; for (i=0; i < bufferSize; ++i) { buffer[i] = 'a' + (i%26); } // write to the file tSize nrRemaining; for (nrRemaining = fileTotalSize; nrRemaining > 0; nrRemaining -= bufferSize ) { int curSize = ( bufferSize < nrRemaining ) ? bufferSize : (int)nrRemaining; hdfsWrite(fs, writeFile, (void*)buffer, curSize); } free(buffer); hdfsCloseFile(fs, writeFile); hdfsDisconnect(fs); return 0; } /** * vim: ts=4: sw=4: et: */

  HADOOP_HOME  JAVA_HOME HADOOP_CONF_DIR  CLASSPATH
HADOOP_HOME=/usr/home/hadoop
export HADOOP_HOME

for i in $HADOOP_HOME/*.jar ; do
    CLASSPATH=$CLASSPATH:$i
done

for i in $HADOOP_HOME/lib/*.jar ; do
    CLASSPATH=$CLASSPATH:$i
done

HADOOP_CONF_DIR=$HADOOP_HOME/conf
CLASSPATH=$CLASSPATH:$HADOOP_CONF_DIR
export  HADOOP_CONF_DIR CLASSPATH
  CLASSPATH     $HADOOP_CONF_DIR
blocksize         HADOOP_CONF_DIR   
     $HADOOP_HOME/src/c++/libhdfs  hdfs.c
hdfsFile hdfsOpenFile(hdfsFS fs, const char* path, int flags, 
                      int bufferSize, short replication, tSize blockSize){}

  hdfsJniHelper.c :
JNIEnv* getJNIEnv(void){}  


gcc  hdfs_write.c -I${HADOOP_HOME}/src/c++/libhdfs -I${JAVA_HOME}/include -I${JAVA_HOME}/include/linux -L${HADOOP_HOME}/libhdfs -lhdfs -o hdfs_write

hdfs_write <filename> <filesize> <buffersize>