/*
* Copyright (C) 2012, Google Inc.
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* - Neither the name of the Eclipse Foundation, Inc. nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.eclipse.jgit.http.server;
import static org.eclipse.jgit.http.server.ServletUtils.isChunked;
import javax.servlet.http.HttpServletRequest;
/** Parses Git client User-Agent strings. */
public class ClientVersionUtil {
private static final int[] v1_7_5 = { 1, 7, 5 };
private static final int[] v1_7_8_6 = { 1, 7, 8, 6 };
private static final int[] v1_7_9 = { 1, 7, 9 };
/** @return maximum version array, indicating an invalid version of Git. */
public static int[] invalidVersion() {
return new int[] { Integer.MAX_VALUE };
}
/**
* Parse a Git client User-Agent header value.
*
* @param version
* git client version string, of the form "git/1.7.9".
* @return components of the version string. {@link #invalidVersion()} if
* the version string cannot be parsed.
*/
public static int[] parseVersion(String version) {
if (version != null && version.startsWith("git/"))
return splitVersion(version.substring("git/".length()));
return invalidVersion();
}
private static int[] splitVersion(String versionString) {
char[] str = versionString.toCharArray();
int[] ver = new int[4];
int end = 0;
int acc = 0;
for (int i = 0; i < str.length; i++) {
char c = str[i];
if ('0' <= c && c <= '9') {
acc *= 10;
acc += c - '0';
} else if (c == '.') {
if (end == ver.length)
ver = grow(ver);
ver[end++] = acc;
acc = 0;
} else if (c == 'g' && 0 < i && str[i - 1] == '.' && 0 < end) {
// Non-tagged builds may contain a mangled git describe output.
// "1.7.6.1.45.gbe0cc". The 45 isn't a valid component. Drop it.
ver[end - 1] = 0;
acc = 0;
break;
} else if (c == '-' && (i + 2) < str.length
&& str[i + 1] == 'r' && str[i + 2] == 'c') {
// Release candidates aren't the same as a final release.
if (acc > 0)
acc--;
break;
} else
break;
}
if (acc != 0) {
if (end == ver.length)
ver = grow(ver);
ver[end++] = acc;
} else {
while (0 < end && ver[end - 1] == 0)
end--;
}
if (end < ver.length) {
int[] n = new int[end];
System.arraycopy(ver, 0, n, 0, end);
ver = n;
}
return ver;
}
private static int[] grow(int[] tmp) {
int[] n = new int[tmp.length + 1];
System.arraycopy(tmp, 0, n, 0, tmp.length);
return n;
}
/**
* Compare two version strings for natural ordering.
*
* @param a
* first parsed version string.
* @param b
* second parsed version string.
* @return < 0 if a is before b; 0 if a equals b; >0 if a is after b.
*/
public static int compare(int[] a, int[] b) {
for (int i = 0; i < a.length && i < b.length; i++) {
int cmp = a[i] - b[i];
if (cmp != 0)
return cmp;
}
return a.length - b.length;
}
/**
* Convert a parsed version back to a string.
*
* @param ver
* the parsed version array.
* @return a string, e.g. "1.6.6.0".
*/
public static String toString(int[] ver) {
StringBuilder b = new StringBuilder();
for (int v : ver) {
if (b.length() > 0)
b.append('.');
b.append(v);
}
return b.toString();
}
/**
* Check if a Git client has the known push status bug.
* <p>
* These buggy clients do not display the status report from a failed push
* over HTTP.
*
* @param version
* parsed version of the Git client software.
* @return true if the bug is present.
*/
public static boolean hasPushStatusBug(int[] version) {
int cmp = compare(version, v1_7_8_6);
if (cmp < 0)
return true; // Everything before 1.7.8.6 is known broken.
else if (cmp == 0)
return false; // 1.7.8.6 contained the bug fix.
if (compare(version, v1_7_9) <= 0)
return true; // 1.7.9 shipped before 1.7.8.6 and has the bug.
return false; // 1.7.9.1 and later are fixed.
}
/**
* Check if a Git client has the known chunked request body encoding bug.
* <p>
* Git 1.7.5 contains a unique bug where chunked requests are malformed.
* This applies to both fetch and push.
*
* @param version
* parsed version of the Git client software.
* @param request
* incoming HTTP request.
* @return true if the client has the chunked encoding bug.
*/
public static boolean hasChunkedEncodingRequestBug(
int[] version, HttpServletRequest request) {
return compare(version, v1_7_5) == 0 && isChunked(request);
}
private ClientVersionUtil() {
}
}