/*
* 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.
*/
package org.apache.felix.gogo.shell;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.URI;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.felix.gogo.options.Option;
import org.apache.felix.gogo.options.Options;
import org.apache.felix.service.command.CommandSession;
/**
* Posix-like utilities.
*
* @see http://www.opengroup.org/onlinepubs/009695399/utilities/contents.html
*/
public class Posix
{
static final String[] functions = { "cat", "echo", "grep" };
public void cat(CommandSession session, String[] args) throws Exception
{
if (args.length == 0)
{
copy(System.in, System.out);
return;
}
URI cwd = Shell.cwd(session);
for (String arg : args)
{
copy(cwd.resolve(arg), System.out);
}
}
public void echo(Object[] args)
{
StringBuilder buf = new StringBuilder();
if (args == null)
{
System.out.println("Null");
return;
}
for (Object arg : args)
{
if (buf.length() > 0)
buf.append(' ');
buf.append(String.valueOf(arg));
}
System.out.println(buf);
}
public boolean grep(CommandSession session, String[] argv) throws IOException
{
final String[] usage = {
"grep - search for PATTERN in each FILE or standard input.",
"Usage: grep [OPTIONS] PATTERN [FILES]",
" -? --help show help",
" -i --ignore-case ignore case distinctions",
" -n --line-number prefix each line with line number within its input file",
" -q --quiet, --silent suppress all normal output",
" -v --invert-match select non-matching lines" };
Option opt = Options.compile(usage).parse(argv);
if (opt.isSet("help"))
{
opt.usage();
return true;
}
List<String> args = opt.args();
if (args.size() == 0)
{
throw opt.usageError("no pattern supplied.");
}
String regex = args.remove(0);
if (opt.isSet("ignore-case"))
{
regex = "(?i)" + regex;
}
if (args.isEmpty())
{
args.add(null);
}
StringBuilder buf = new StringBuilder();
if (args.size() > 1)
{
buf.append("%1$s:");
}
if (opt.isSet("line-number"))
{
buf.append("%2$s:");
}
buf.append("%3$s");
String format = buf.toString();
Pattern pattern = Pattern.compile(regex);
boolean status = true;
boolean match = false;
for (String arg : args)
{
InputStream in = null;
try
{
URI cwd = Shell.cwd(session);
in = (arg == null) ? System.in : cwd.resolve(arg).toURL().openStream();
BufferedReader rdr = new BufferedReader(new InputStreamReader(in));
int line = 0;
String s;
while ((s = rdr.readLine()) != null)
{
line++;
Matcher matcher = pattern.matcher(s);
if (!(matcher.find() ^ !opt.isSet("invert-match")))
{
match = true;
if (opt.isSet("quiet"))
break;
System.out.println(String.format(format, arg, line, s));
}
}
if (match && opt.isSet("quiet"))
{
break;
}
}
catch (IOException e)
{
System.err.println("grep: " + e.getMessage());
status = false;
}
finally
{
if (arg != null && in != null)
{
in.close();
}
}
}
return match && status;
}
public static void copy(URI source, OutputStream out) throws IOException {
InputStream in = source.toURL().openStream();
try {
copy(in, out);
} finally {
in.close();
}
}
public static void copy(InputStream in, OutputStream out) throws IOException {
byte buf[] = new byte[10240];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
out.flush();
}
}