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The Qbicc builder for the java.base JDK module
/*
* Copyright (c) 2020, Red Hat Inc.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package jdk.internal.platform;
import java.io.IOException;
import java.io.UncheckedIOException;
import java.math.BigInteger;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import java.util.function.Function;
import java.util.stream.Stream;
/**
* Cgroup version agnostic controller logic
*
*/
public interface CgroupSubsystemController {
public static final String EMPTY_STR = "";
public String path();
/**
* getStringValue
*
* Return the first line of the file "param" argument from the controller.
*
* TODO: Consider using weak references for caching BufferedReader object.
*
* @param controller
* @param param
* @return Returns the contents of the file specified by param or null if
* an error occurs.
*/
public static String getStringValue(CgroupSubsystemController controller, String param) {
if (controller == null) return null;
try {
return CgroupUtil.readStringValue(controller, param);
}
catch (IOException e) {
return null;
}
}
/**
* Get an entry from file "param" within the "controller" directory path
* which matches string "match". Applies "conversion" to the matching line.
*
* @param controller
* @param param
* @param match
* @param conversion
* @param defaultRetval
* @return The long value as derived by applying "conversion" to the matching
* line or "defaultRetval" if there was an error or no match found.
*/
public static long getLongValueMatchingLine(CgroupSubsystemController controller,
String param,
String match,
Function conversion,
long defaultRetval) {
long retval = defaultRetval;
if (controller == null) {
return retval;
}
try {
Path filePath = Paths.get(controller.path(), param);
List lines = CgroupUtil.readAllLinesPrivileged(filePath);
for (String line : lines) {
if (line.startsWith(match)) {
retval = conversion.apply(line);
break;
}
}
} catch (IOException e) {
// Ignore. Default is unlimited.
}
return retval;
}
/**
* Get a long value from directory "controller" and file "param", by
* applying "conversion" to the string value within the file.
*
* @param controller
* @param param
* @param conversion
* @param defaultRetval
* @return The converted long value or "defaultRetval" if there was an
* error.
*/
public static long getLongValue(CgroupSubsystemController controller,
String param,
Function conversion,
long defaultRetval) {
String strval = getStringValue(controller, param);
if (strval == null) return defaultRetval;
return conversion.apply(strval);
}
/**
* Get a double value from file "param" within "controller".
*
* @param controller
* @param param
* @param defaultRetval
* @return The double value or "defaultRetval" if there was an error.
*/
public static double getDoubleValue(CgroupSubsystemController controller, String param, double defaultRetval) {
String strval = getStringValue(controller, param);
if (strval == null) return defaultRetval;
double retval = Double.parseDouble(strval);
return retval;
}
/**
* getLongEntry
*
* Return the long value from the line containing the string "entryname"
* within file "param" in the "controller".
*
* TODO: Consider using weak references for caching BufferedReader object.
*
* @param controller
* @param param
* @param entryname
* @return long value or "defaultRetval" if there was an error or no match
* was found.
*/
public static long getLongEntry(CgroupSubsystemController controller, String param, String entryname, long defaultRetval) {
if (controller == null) return defaultRetval;
try (Stream lines = CgroupUtil.readFilePrivileged(Paths.get(controller.path(), param))) {
Optional result = lines.map(line -> line.split(" "))
.filter(line -> (line.length == 2 &&
line[0].equals(entryname)))
.map(line -> line[1])
.findFirst();
return result.isPresent() ? Long.parseLong(result.get()) : defaultRetval;
} catch (UncheckedIOException e) {
return defaultRetval;
} catch (IOException e) {
return defaultRetval;
}
}
/**
* stringRangeToIntArray
*
* Convert a string in the form of 1,3-4,6 to an array of
* integers containing all the numbers in the range.
*
* @param range
* @return int[] containing a sorted list of numbers as represented by
* the string range. Returns null if there was an error or the input
* was an empty string.
*/
public static int[] stringRangeToIntArray(String range) {
if (range == null || EMPTY_STR.equals(range)) return null;
ArrayList results = new ArrayList<>();
String strs[] = range.split(",");
for (String str : strs) {
if (str.contains("-")) {
String lohi[] = str.split("-");
// validate format
if (lohi.length != 2) {
continue;
}
int lo = Integer.parseInt(lohi[0]);
int hi = Integer.parseInt(lohi[1]);
for (int i = lo; i <= hi; i++) {
results.add(i);
}
}
else {
results.add(Integer.parseInt(str));
}
}
// sort results
results.sort(null);
// convert ArrayList to primitive int array
int[] ints = new int[results.size()];
int i = 0;
for (Integer n : results) {
ints[i++] = n;
}
return ints;
}
/**
* Convert a number from its string representation to a long.
*
* @param strval
* @param overflowRetval
* @param defaultRetval
* @return The converted long value. "overflowRetval" is returned if the
* string representation exceeds the range of type long.
* "defaultRetval" is returned if another type of error occurred
* during conversion.
*/
public static long convertStringToLong(String strval, long overflowRetval, long defaultRetval) {
long retval = defaultRetval;
if (strval == null) return retval;
try {
retval = Long.parseLong(strval);
} catch (NumberFormatException e) {
// For some properties (e.g. memory.limit_in_bytes, cgroups v1) we may overflow
// the range of signed long. In this case, return overflowRetval
BigInteger b = new BigInteger(strval);
if (b.compareTo(BigInteger.valueOf(Long.MAX_VALUE)) > 0) {
return overflowRetval;
}
}
return retval;
}
}
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