/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed 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.
*/
import java.io.*;
import java.util.*;
// usage: java ZoneCompiler <setup file> <data directory> <output directory> <tzdata version>
//
// Compile a set of tzfile-formatted files into a single file containing an index.
//
// The compilation is controlled by a setup file, which is provided as a
// command-line argument. The setup file has the form:
//
// Link <toName> <fromName>
// ...
// <zone filename>
// ...
//
// Note that the links must be declared prior to the zone names.
// A zone name is a filename relative to the source directory such as
// 'GMT', 'Africa/Dakar', or 'America/Argentina/Jujuy'.
//
// Use the 'zic' command-line tool to convert from flat files
// (such as 'africa' or 'northamerica') to a directory
// hierarchy suitable for this tool (containing files such as 'data/Africa/Abidjan').
//
public class ZoneCompactor {
// Maximum number of characters in a zone name, including '\0' terminator.
private static final int MAXNAME = 40;
// Zone name synonyms.
private Map<String,String> links = new HashMap<String,String>();
// File offsets by zone name.
private Map<String,Integer> offsets = new HashMap<String,Integer>();
// File lengths by zone name.
private Map<String,Integer> lengths = new HashMap<String,Integer>();
// Concatenate the contents of 'inFile' onto 'out'.
private static void copyFile(File inFile, OutputStream out) throws Exception {
byte[] ret = new byte[0];
InputStream in = new FileInputStream(inFile);
byte[] buf = new byte[8192];
while (true) {
int nbytes = in.read(buf);
if (nbytes == -1) {
break;
}
out.write(buf, 0, nbytes);
byte[] nret = new byte[ret.length + nbytes];
System.arraycopy(ret, 0, nret, 0, ret.length);
System.arraycopy(buf, 0, nret, ret.length, nbytes);
ret = nret;
}
out.flush();
}
public ZoneCompactor(String setupFile, String dataDirectory, String zoneTabFile, String outputDirectory, String version) throws Exception {
// Read the setup file and concatenate all the data.
ByteArrayOutputStream allData = new ByteArrayOutputStream();
BufferedReader reader = new BufferedReader(new FileReader(setupFile));
String s;
int offset = 0;
while ((s = reader.readLine()) != null) {
s = s.trim();
if (s.startsWith("Link")) {
StringTokenizer st = new StringTokenizer(s);
st.nextToken();
String to = st.nextToken();
String from = st.nextToken();
links.put(from, to);
} else {
String link = links.get(s);
if (link == null) {
File sourceFile = new File(dataDirectory, s);
long length = sourceFile.length();
offsets.put(s, offset);
lengths.put(s, (int) length);
offset += length;
copyFile(sourceFile, allData);
}
}
}
reader.close();
// Fill in fields for links.
Iterator<String> it = links.keySet().iterator();
while (it.hasNext()) {
String from = it.next();
String to = links.get(from);
offsets.put(from, offsets.get(to));
lengths.put(from, lengths.get(to));
}
// Create/truncate the destination file.
RandomAccessFile f = new RandomAccessFile(new File(outputDirectory, "tzdata"), "rw");
f.setLength(0);
// Write the header.
// byte[12] tzdata_version -- 'tzdata2012f\0'
// int index_offset -- so we can slip in extra header fields in a backwards-compatible way
// int data_offset
// int zonetab_offset
// tzdata_version
f.write(toAscii(new byte[12], version));
// Write dummy values for the three offsets, and remember where we need to seek back to later
// when we have the real values.
int index_offset_offset = (int) f.getFilePointer();
f.writeInt(0);
int data_offset_offset = (int) f.getFilePointer();
f.writeInt(0);
int zonetab_offset_offset = (int) f.getFilePointer();
f.writeInt(0);
int index_offset = (int) f.getFilePointer();
// Write the index.
ArrayList<String> sortedOlsonIds = new ArrayList<String>();
sortedOlsonIds.addAll(offsets.keySet());
Collections.sort(sortedOlsonIds);
it = sortedOlsonIds.iterator();
while (it.hasNext()) {
String zoneName = it.next();
if (zoneName.length() >= MAXNAME) {
throw new RuntimeException("zone filename too long: " + zoneName.length());
}
// Follow the chain of links to work out where the real data for this zone lives.
String actualZoneName = zoneName;
while (links.get(actualZoneName) != null) {
actualZoneName = links.get(actualZoneName);
}
f.write(toAscii(new byte[MAXNAME], zoneName));
f.writeInt(offsets.get(actualZoneName));
f.writeInt(lengths.get(actualZoneName));
f.writeInt(0); // Used to be raw GMT offset. No longer used.
}
int data_offset = (int) f.getFilePointer();
// Write the data.
f.write(allData.toByteArray());
int zonetab_offset = (int) f.getFilePointer();
// Copy the zone.tab.
reader = new BufferedReader(new FileReader(zoneTabFile));
while ((s = reader.readLine()) != null) {
if (!s.startsWith("#")) {
f.writeBytes(s);
f.write('\n');
}
}
reader.close();
// Go back and fix up the offsets in the header.
f.seek(index_offset_offset);
f.writeInt(index_offset);
f.seek(data_offset_offset);
f.writeInt(data_offset);
f.seek(zonetab_offset_offset);
f.writeInt(zonetab_offset);
f.close();
}
private static byte[] toAscii(byte[] dst, String src) {
for (int i = 0; i < src.length(); ++i) {
if (src.charAt(i) > '~') {
throw new RuntimeException("non-ASCII string: " + src);
}
dst[i] = (byte) src.charAt(i);
}
return dst;
}
public static void main(String[] args) throws Exception {
if (args.length != 5) {
System.err.println("usage: java ZoneCompactor <setup file> <data directory> <zone.tab file> <output directory> <tzdata version>");
System.exit(0);
}
new ZoneCompactor(args[0], args[1], args[2], args[3], args[4]);
}
}