Neil Fuller | 56166d3 | 2017-06-12 12:57:10 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2017 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
Neil Fuller | 86e72c5 | 2017-06-12 15:36:06 +0100 | [diff] [blame] | 16 | |
| 17 | import java.io.*; |
| 18 | import java.util.*; |
| 19 | |
| 20 | // usage: java ZoneCompiler <setup file> <data directory> <output directory> <tzdata version> |
| 21 | // |
| 22 | // Compile a set of tzfile-formatted files into a single file containing an index. |
| 23 | // |
| 24 | // The compilation is controlled by a setup file, which is provided as a |
| 25 | // command-line argument. The setup file has the form: |
| 26 | // |
| 27 | // Link <toName> <fromName> |
| 28 | // ... |
| 29 | // <zone filename> |
| 30 | // ... |
| 31 | // |
| 32 | // Note that the links must be declared prior to the zone names. |
| 33 | // A zone name is a filename relative to the source directory such as |
| 34 | // 'GMT', 'Africa/Dakar', or 'America/Argentina/Jujuy'. |
| 35 | // |
| 36 | // Use the 'zic' command-line tool to convert from flat files |
| 37 | // (such as 'africa' or 'northamerica') to a directory |
| 38 | // hierarchy suitable for this tool (containing files such as 'data/Africa/Abidjan'). |
| 39 | // |
| 40 | |
| 41 | public class ZoneCompactor { |
| 42 | // Maximum number of characters in a zone name, including '\0' terminator. |
| 43 | private static final int MAXNAME = 40; |
| 44 | |
| 45 | // Zone name synonyms. |
| 46 | private Map<String,String> links = new HashMap<String,String>(); |
| 47 | |
| 48 | // File offsets by zone name. |
| 49 | private Map<String,Integer> offsets = new HashMap<String,Integer>(); |
| 50 | |
| 51 | // File lengths by zone name. |
| 52 | private Map<String,Integer> lengths = new HashMap<String,Integer>(); |
| 53 | |
| 54 | // Concatenate the contents of 'inFile' onto 'out'. |
| 55 | private static void copyFile(File inFile, OutputStream out) throws Exception { |
| 56 | byte[] ret = new byte[0]; |
| 57 | |
| 58 | InputStream in = new FileInputStream(inFile); |
| 59 | byte[] buf = new byte[8192]; |
| 60 | while (true) { |
| 61 | int nbytes = in.read(buf); |
| 62 | if (nbytes == -1) { |
| 63 | break; |
| 64 | } |
| 65 | out.write(buf, 0, nbytes); |
| 66 | |
| 67 | byte[] nret = new byte[ret.length + nbytes]; |
| 68 | System.arraycopy(ret, 0, nret, 0, ret.length); |
| 69 | System.arraycopy(buf, 0, nret, ret.length, nbytes); |
| 70 | ret = nret; |
| 71 | } |
| 72 | out.flush(); |
| 73 | } |
| 74 | |
| 75 | public ZoneCompactor(String setupFile, String dataDirectory, String zoneTabFile, String outputDirectory, String version) throws Exception { |
| 76 | // Read the setup file and concatenate all the data. |
| 77 | ByteArrayOutputStream allData = new ByteArrayOutputStream(); |
| 78 | BufferedReader reader = new BufferedReader(new FileReader(setupFile)); |
| 79 | String s; |
| 80 | int offset = 0; |
| 81 | while ((s = reader.readLine()) != null) { |
| 82 | s = s.trim(); |
| 83 | if (s.startsWith("Link")) { |
| 84 | StringTokenizer st = new StringTokenizer(s); |
| 85 | st.nextToken(); |
| 86 | String to = st.nextToken(); |
| 87 | String from = st.nextToken(); |
| 88 | links.put(from, to); |
| 89 | } else { |
| 90 | String link = links.get(s); |
| 91 | if (link == null) { |
| 92 | File sourceFile = new File(dataDirectory, s); |
| 93 | long length = sourceFile.length(); |
| 94 | offsets.put(s, offset); |
| 95 | lengths.put(s, (int) length); |
| 96 | |
| 97 | offset += length; |
| 98 | copyFile(sourceFile, allData); |
| 99 | } |
| 100 | } |
| 101 | } |
| 102 | reader.close(); |
| 103 | |
| 104 | // Fill in fields for links. |
| 105 | Iterator<String> it = links.keySet().iterator(); |
| 106 | while (it.hasNext()) { |
| 107 | String from = it.next(); |
| 108 | String to = links.get(from); |
| 109 | |
| 110 | offsets.put(from, offsets.get(to)); |
| 111 | lengths.put(from, lengths.get(to)); |
| 112 | } |
| 113 | |
| 114 | // Create/truncate the destination file. |
| 115 | RandomAccessFile f = new RandomAccessFile(new File(outputDirectory, "tzdata"), "rw"); |
| 116 | f.setLength(0); |
| 117 | |
| 118 | // Write the header. |
| 119 | |
| 120 | // byte[12] tzdata_version -- 'tzdata2012f\0' |
| 121 | // int index_offset -- so we can slip in extra header fields in a backwards-compatible way |
| 122 | // int data_offset |
| 123 | // int zonetab_offset |
| 124 | |
| 125 | // tzdata_version |
| 126 | f.write(toAscii(new byte[12], version)); |
| 127 | |
| 128 | // Write dummy values for the three offsets, and remember where we need to seek back to later |
| 129 | // when we have the real values. |
| 130 | int index_offset_offset = (int) f.getFilePointer(); |
| 131 | f.writeInt(0); |
| 132 | int data_offset_offset = (int) f.getFilePointer(); |
| 133 | f.writeInt(0); |
| 134 | int zonetab_offset_offset = (int) f.getFilePointer(); |
| 135 | f.writeInt(0); |
| 136 | |
| 137 | int index_offset = (int) f.getFilePointer(); |
| 138 | |
| 139 | // Write the index. |
| 140 | ArrayList<String> sortedOlsonIds = new ArrayList<String>(); |
| 141 | sortedOlsonIds.addAll(offsets.keySet()); |
| 142 | Collections.sort(sortedOlsonIds); |
| 143 | it = sortedOlsonIds.iterator(); |
| 144 | while (it.hasNext()) { |
| 145 | String zoneName = it.next(); |
| 146 | if (zoneName.length() >= MAXNAME) { |
| 147 | throw new RuntimeException("zone filename too long: " + zoneName.length()); |
| 148 | } |
| 149 | |
| 150 | // Follow the chain of links to work out where the real data for this zone lives. |
| 151 | String actualZoneName = zoneName; |
| 152 | while (links.get(actualZoneName) != null) { |
| 153 | actualZoneName = links.get(actualZoneName); |
| 154 | } |
| 155 | |
| 156 | f.write(toAscii(new byte[MAXNAME], zoneName)); |
| 157 | f.writeInt(offsets.get(actualZoneName)); |
| 158 | f.writeInt(lengths.get(actualZoneName)); |
| 159 | f.writeInt(0); // Used to be raw GMT offset. No longer used. |
| 160 | } |
| 161 | |
| 162 | int data_offset = (int) f.getFilePointer(); |
| 163 | |
| 164 | // Write the data. |
| 165 | f.write(allData.toByteArray()); |
| 166 | |
| 167 | int zonetab_offset = (int) f.getFilePointer(); |
| 168 | |
| 169 | // Copy the zone.tab. |
| 170 | reader = new BufferedReader(new FileReader(zoneTabFile)); |
| 171 | while ((s = reader.readLine()) != null) { |
| 172 | if (!s.startsWith("#")) { |
| 173 | f.writeBytes(s); |
| 174 | f.write('\n'); |
| 175 | } |
| 176 | } |
| 177 | reader.close(); |
| 178 | |
| 179 | // Go back and fix up the offsets in the header. |
| 180 | f.seek(index_offset_offset); |
| 181 | f.writeInt(index_offset); |
| 182 | f.seek(data_offset_offset); |
| 183 | f.writeInt(data_offset); |
| 184 | f.seek(zonetab_offset_offset); |
| 185 | f.writeInt(zonetab_offset); |
| 186 | |
| 187 | f.close(); |
| 188 | } |
| 189 | |
| 190 | private static byte[] toAscii(byte[] dst, String src) { |
| 191 | for (int i = 0; i < src.length(); ++i) { |
| 192 | if (src.charAt(i) > '~') { |
| 193 | throw new RuntimeException("non-ASCII string: " + src); |
| 194 | } |
| 195 | dst[i] = (byte) src.charAt(i); |
| 196 | } |
| 197 | return dst; |
| 198 | } |
| 199 | |
| 200 | public static void main(String[] args) throws Exception { |
| 201 | if (args.length != 5) { |
| 202 | System.err.println("usage: java ZoneCompactor <setup file> <data directory> <zone.tab file> <output directory> <tzdata version>"); |
| 203 | System.exit(0); |
| 204 | } |
| 205 | new ZoneCompactor(args[0], args[1], args[2], args[3], args[4]); |
| 206 | } |
| 207 | } |