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Posted to commits@hbase.apache.org by mi...@apache.org on 2016/02/12 22:25:44 UTC
[19/51] [partial] hbase-site git commit: Published site at
85e1d9a109341c5f4aabb0e82c96ab52e99a6d72.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/526c7822/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.WALHdrContext.html
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diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.WALHdrContext.html b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.WALHdrContext.html
index 4dfc99f..98a2d4e 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.WALHdrContext.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/ProtobufLogReader.WALHdrContext.html
@@ -53,373 +53,374 @@
<span class="sourceLineNo">045</span>import org.apache.hadoop.hbase.wal.WAL.Entry;<a name="line.45"></a>
<span class="sourceLineNo">046</span><a name="line.46"></a>
<span class="sourceLineNo">047</span>import com.google.protobuf.CodedInputStream;<a name="line.47"></a>
-<span class="sourceLineNo">048</span><a name="line.48"></a>
-<span class="sourceLineNo">049</span>/**<a name="line.49"></a>
-<span class="sourceLineNo">050</span> * A Protobuf based WAL has the following structure:<a name="line.50"></a>
-<span class="sourceLineNo">051</span> * <p><a name="line.51"></a>
-<span class="sourceLineNo">052</span> * &lt;PB_WAL_MAGIC&gt;&lt;WALHeader&gt;&lt;WALEdits&gt;...&lt;WALEdits&gt;&lt;Trailer&gt;<a name="line.52"></a>
-<span class="sourceLineNo">053</span> * &lt;TrailerSize&gt; &lt;PB_WAL_COMPLETE_MAGIC&gt;<a name="line.53"></a>
-<span class="sourceLineNo">054</span> * </p><a name="line.54"></a>
-<span class="sourceLineNo">055</span> * The Reader reads meta information (WAL Compression state, WALTrailer, etc) in<a name="line.55"></a>
-<span class="sourceLineNo">056</span> * ProtobufLogReader#initReader(FSDataInputStream). A WALTrailer is an extensible structure<a name="line.56"></a>
-<span class="sourceLineNo">057</span> * which is appended at the end of the WAL. This is empty for now; it can contain some meta<a name="line.57"></a>
-<span class="sourceLineNo">058</span> * information such as Region level stats, etc in future.<a name="line.58"></a>
-<span class="sourceLineNo">059</span> */<a name="line.59"></a>
-<span class="sourceLineNo">060</span>@InterfaceAudience.LimitedPrivate({HBaseInterfaceAudience.COPROC, HBaseInterfaceAudience.PHOENIX,<a name="line.60"></a>
-<span class="sourceLineNo">061</span> HBaseInterfaceAudience.CONFIG})<a name="line.61"></a>
-<span class="sourceLineNo">062</span>public class ProtobufLogReader extends ReaderBase {<a name="line.62"></a>
-<span class="sourceLineNo">063</span> private static final Log LOG = LogFactory.getLog(ProtobufLogReader.class);<a name="line.63"></a>
-<span class="sourceLineNo">064</span> // public for WALFactory until we move everything to o.a.h.h.wal<a name="line.64"></a>
-<span class="sourceLineNo">065</span> @InterfaceAudience.Private<a name="line.65"></a>
-<span class="sourceLineNo">066</span> public static final byte[] PB_WAL_MAGIC = Bytes.toBytes("PWAL");<a name="line.66"></a>
-<span class="sourceLineNo">067</span> // public for TestWALSplit<a name="line.67"></a>
-<span class="sourceLineNo">068</span> @InterfaceAudience.Private<a name="line.68"></a>
-<span class="sourceLineNo">069</span> public static final byte[] PB_WAL_COMPLETE_MAGIC = Bytes.toBytes("LAWP");<a name="line.69"></a>
-<span class="sourceLineNo">070</span> /**<a name="line.70"></a>
-<span class="sourceLineNo">071</span> * Configuration name of WAL Trailer's warning size. If a waltrailer's size is greater than the<a name="line.71"></a>
-<span class="sourceLineNo">072</span> * configured size, providers should log a warning. e.g. this is used with Protobuf reader/writer.<a name="line.72"></a>
-<span class="sourceLineNo">073</span> */<a name="line.73"></a>
-<span class="sourceLineNo">074</span> static final String WAL_TRAILER_WARN_SIZE = "hbase.regionserver.waltrailer.warn.size";<a name="line.74"></a>
-<span class="sourceLineNo">075</span> static final int DEFAULT_WAL_TRAILER_WARN_SIZE = 1024 * 1024; // 1MB<a name="line.75"></a>
-<span class="sourceLineNo">076</span><a name="line.76"></a>
-<span class="sourceLineNo">077</span> protected FSDataInputStream inputStream;<a name="line.77"></a>
-<span class="sourceLineNo">078</span> protected Codec.Decoder cellDecoder;<a name="line.78"></a>
-<span class="sourceLineNo">079</span> protected WALCellCodec.ByteStringUncompressor byteStringUncompressor;<a name="line.79"></a>
-<span class="sourceLineNo">080</span> protected boolean hasCompression = false;<a name="line.80"></a>
-<span class="sourceLineNo">081</span> protected boolean hasTagCompression = false;<a name="line.81"></a>
-<span class="sourceLineNo">082</span> // walEditsStopOffset is the position of the last byte to read. After reading the last WALEdit<a name="line.82"></a>
-<span class="sourceLineNo">083</span> // entry in the wal, the inputstream's position is equal to walEditsStopOffset.<a name="line.83"></a>
-<span class="sourceLineNo">084</span> private long walEditsStopOffset;<a name="line.84"></a>
-<span class="sourceLineNo">085</span> private boolean trailerPresent;<a name="line.85"></a>
-<span class="sourceLineNo">086</span> protected WALTrailer trailer;<a name="line.86"></a>
-<span class="sourceLineNo">087</span> // maximum size of the wal Trailer in bytes. If a user writes/reads a trailer with size larger<a name="line.87"></a>
-<span class="sourceLineNo">088</span> // than this size, it is written/read respectively, with a WARN message in the log.<a name="line.88"></a>
-<span class="sourceLineNo">089</span> protected int trailerWarnSize;<a name="line.89"></a>
-<span class="sourceLineNo">090</span> private static List<String> writerClsNames = new ArrayList<String>();<a name="line.90"></a>
-<span class="sourceLineNo">091</span> static {<a name="line.91"></a>
-<span class="sourceLineNo">092</span> writerClsNames.add(ProtobufLogWriter.class.getSimpleName());<a name="line.92"></a>
-<span class="sourceLineNo">093</span> }<a name="line.93"></a>
-<span class="sourceLineNo">094</span> <a name="line.94"></a>
-<span class="sourceLineNo">095</span> // cell codec classname<a name="line.95"></a>
-<span class="sourceLineNo">096</span> private String codecClsName = null;<a name="line.96"></a>
-<span class="sourceLineNo">097</span><a name="line.97"></a>
-<span class="sourceLineNo">098</span> enum WALHdrResult {<a name="line.98"></a>
-<span class="sourceLineNo">099</span> EOF, // stream is at EOF when method starts<a name="line.99"></a>
-<span class="sourceLineNo">100</span> SUCCESS,<a name="line.100"></a>
-<span class="sourceLineNo">101</span> UNKNOWN_WRITER_CLS // name of writer class isn't recognized<a name="line.101"></a>
-<span class="sourceLineNo">102</span> }<a name="line.102"></a>
-<span class="sourceLineNo">103</span> <a name="line.103"></a>
-<span class="sourceLineNo">104</span> // context for WALHdr carrying information such as Cell Codec classname<a name="line.104"></a>
-<span class="sourceLineNo">105</span> static class WALHdrContext {<a name="line.105"></a>
-<span class="sourceLineNo">106</span> WALHdrResult result;<a name="line.106"></a>
-<span class="sourceLineNo">107</span> String cellCodecClsName;<a name="line.107"></a>
-<span class="sourceLineNo">108</span> <a name="line.108"></a>
-<span class="sourceLineNo">109</span> WALHdrContext(WALHdrResult result, String cellCodecClsName) {<a name="line.109"></a>
-<span class="sourceLineNo">110</span> this.result = result;<a name="line.110"></a>
-<span class="sourceLineNo">111</span> this.cellCodecClsName = cellCodecClsName;<a name="line.111"></a>
-<span class="sourceLineNo">112</span> }<a name="line.112"></a>
-<span class="sourceLineNo">113</span> WALHdrResult getResult() {<a name="line.113"></a>
-<span class="sourceLineNo">114</span> return result;<a name="line.114"></a>
-<span class="sourceLineNo">115</span> }<a name="line.115"></a>
-<span class="sourceLineNo">116</span> String getCellCodecClsName() {<a name="line.116"></a>
-<span class="sourceLineNo">117</span> return cellCodecClsName;<a name="line.117"></a>
-<span class="sourceLineNo">118</span> }<a name="line.118"></a>
-<span class="sourceLineNo">119</span> }<a name="line.119"></a>
-<span class="sourceLineNo">120</span><a name="line.120"></a>
-<span class="sourceLineNo">121</span> public ProtobufLogReader() {<a name="line.121"></a>
-<span class="sourceLineNo">122</span> super();<a name="line.122"></a>
-<span class="sourceLineNo">123</span> }<a name="line.123"></a>
-<span class="sourceLineNo">124</span><a name="line.124"></a>
-<span class="sourceLineNo">125</span> @Override<a name="line.125"></a>
-<span class="sourceLineNo">126</span> public void close() throws IOException {<a name="line.126"></a>
-<span class="sourceLineNo">127</span> if (this.inputStream != null) {<a name="line.127"></a>
-<span class="sourceLineNo">128</span> this.inputStream.close();<a name="line.128"></a>
-<span class="sourceLineNo">129</span> this.inputStream = null;<a name="line.129"></a>
-<span class="sourceLineNo">130</span> }<a name="line.130"></a>
-<span class="sourceLineNo">131</span> }<a name="line.131"></a>
-<span class="sourceLineNo">132</span><a name="line.132"></a>
-<span class="sourceLineNo">133</span> @Override<a name="line.133"></a>
-<span class="sourceLineNo">134</span> public long getPosition() throws IOException {<a name="line.134"></a>
-<span class="sourceLineNo">135</span> return inputStream.getPos();<a name="line.135"></a>
-<span class="sourceLineNo">136</span> }<a name="line.136"></a>
-<span class="sourceLineNo">137</span><a name="line.137"></a>
-<span class="sourceLineNo">138</span> @Override<a name="line.138"></a>
-<span class="sourceLineNo">139</span> public void reset() throws IOException {<a name="line.139"></a>
-<span class="sourceLineNo">140</span> String clsName = initInternal(null, false);<a name="line.140"></a>
-<span class="sourceLineNo">141</span> initAfterCompression(clsName); // We need a new decoder (at least).<a name="line.141"></a>
-<span class="sourceLineNo">142</span> }<a name="line.142"></a>
-<span class="sourceLineNo">143</span><a name="line.143"></a>
-<span class="sourceLineNo">144</span> @Override<a name="line.144"></a>
-<span class="sourceLineNo">145</span> public void init(FileSystem fs, Path path, Configuration conf, FSDataInputStream stream)<a name="line.145"></a>
-<span class="sourceLineNo">146</span> throws IOException {<a name="line.146"></a>
-<span class="sourceLineNo">147</span> this.trailerWarnSize = conf.getInt(WAL_TRAILER_WARN_SIZE, DEFAULT_WAL_TRAILER_WARN_SIZE);<a name="line.147"></a>
-<span class="sourceLineNo">148</span> super.init(fs, path, conf, stream);<a name="line.148"></a>
-<span class="sourceLineNo">149</span> }<a name="line.149"></a>
-<span class="sourceLineNo">150</span><a name="line.150"></a>
-<span class="sourceLineNo">151</span> @Override<a name="line.151"></a>
-<span class="sourceLineNo">152</span> protected String initReader(FSDataInputStream stream) throws IOException {<a name="line.152"></a>
-<span class="sourceLineNo">153</span> return initInternal(stream, true);<a name="line.153"></a>
-<span class="sourceLineNo">154</span> }<a name="line.154"></a>
-<span class="sourceLineNo">155</span><a name="line.155"></a>
-<span class="sourceLineNo">156</span> /*<a name="line.156"></a>
-<span class="sourceLineNo">157</span> * Returns names of the accepted writer classes<a name="line.157"></a>
-<span class="sourceLineNo">158</span> */<a name="line.158"></a>
-<span class="sourceLineNo">159</span> public List<String> getWriterClsNames() {<a name="line.159"></a>
-<span class="sourceLineNo">160</span> return writerClsNames;<a name="line.160"></a>
-<span class="sourceLineNo">161</span> }<a name="line.161"></a>
-<span class="sourceLineNo">162</span> <a name="line.162"></a>
-<span class="sourceLineNo">163</span> /*<a name="line.163"></a>
-<span class="sourceLineNo">164</span> * Returns the cell codec classname<a name="line.164"></a>
-<span class="sourceLineNo">165</span> */<a name="line.165"></a>
-<span class="sourceLineNo">166</span> public String getCodecClsName() {<a name="line.166"></a>
-<span class="sourceLineNo">167</span> return codecClsName;<a name="line.167"></a>
-<span class="sourceLineNo">168</span> }<a name="line.168"></a>
-<span class="sourceLineNo">169</span><a name="line.169"></a>
-<span class="sourceLineNo">170</span> protected WALHdrContext readHeader(Builder builder, FSDataInputStream stream)<a name="line.170"></a>
-<span class="sourceLineNo">171</span> throws IOException {<a name="line.171"></a>
-<span class="sourceLineNo">172</span> boolean res = builder.mergeDelimitedFrom(stream);<a name="line.172"></a>
-<span class="sourceLineNo">173</span> if (!res) return new WALHdrContext(WALHdrResult.EOF, null);<a name="line.173"></a>
-<span class="sourceLineNo">174</span> if (builder.hasWriterClsName() &&<a name="line.174"></a>
-<span class="sourceLineNo">175</span> !getWriterClsNames().contains(builder.getWriterClsName())) {<a name="line.175"></a>
-<span class="sourceLineNo">176</span> return new WALHdrContext(WALHdrResult.UNKNOWN_WRITER_CLS, null);<a name="line.176"></a>
-<span class="sourceLineNo">177</span> }<a name="line.177"></a>
-<span class="sourceLineNo">178</span> String clsName = null;<a name="line.178"></a>
-<span class="sourceLineNo">179</span> if (builder.hasCellCodecClsName()) {<a name="line.179"></a>
-<span class="sourceLineNo">180</span> clsName = builder.getCellCodecClsName();<a name="line.180"></a>
-<span class="sourceLineNo">181</span> }<a name="line.181"></a>
-<span class="sourceLineNo">182</span> return new WALHdrContext(WALHdrResult.SUCCESS, clsName);<a name="line.182"></a>
-<span class="sourceLineNo">183</span> }<a name="line.183"></a>
-<span class="sourceLineNo">184</span><a name="line.184"></a>
-<span class="sourceLineNo">185</span> private String initInternal(FSDataInputStream stream, boolean isFirst)<a name="line.185"></a>
-<span class="sourceLineNo">186</span> throws IOException {<a name="line.186"></a>
-<span class="sourceLineNo">187</span> close();<a name="line.187"></a>
-<span class="sourceLineNo">188</span> long expectedPos = PB_WAL_MAGIC.length;<a name="line.188"></a>
-<span class="sourceLineNo">189</span> if (stream == null) {<a name="line.189"></a>
-<span class="sourceLineNo">190</span> stream = fs.open(path);<a name="line.190"></a>
-<span class="sourceLineNo">191</span> stream.seek(expectedPos);<a name="line.191"></a>
-<span class="sourceLineNo">192</span> }<a name="line.192"></a>
-<span class="sourceLineNo">193</span> if (stream.getPos() != expectedPos) {<a name="line.193"></a>
-<span class="sourceLineNo">194</span> throw new IOException("The stream is at invalid position: " + stream.getPos());<a name="line.194"></a>
-<span class="sourceLineNo">195</span> }<a name="line.195"></a>
-<span class="sourceLineNo">196</span> // Initialize metadata or, when we reset, just skip the header.<a name="line.196"></a>
-<span class="sourceLineNo">197</span> WALProtos.WALHeader.Builder builder = WALProtos.WALHeader.newBuilder();<a name="line.197"></a>
-<span class="sourceLineNo">198</span> WALHdrContext hdrCtxt = readHeader(builder, stream);<a name="line.198"></a>
-<span class="sourceLineNo">199</span> WALHdrResult walHdrRes = hdrCtxt.getResult();<a name="line.199"></a>
-<span class="sourceLineNo">200</span> if (walHdrRes == WALHdrResult.EOF) {<a name="line.200"></a>
-<span class="sourceLineNo">201</span> throw new EOFException("Couldn't read WAL PB header");<a name="line.201"></a>
-<span class="sourceLineNo">202</span> }<a name="line.202"></a>
-<span class="sourceLineNo">203</span> if (walHdrRes == WALHdrResult.UNKNOWN_WRITER_CLS) {<a name="line.203"></a>
-<span class="sourceLineNo">204</span> throw new IOException("Got unknown writer class: " + builder.getWriterClsName());<a name="line.204"></a>
-<span class="sourceLineNo">205</span> }<a name="line.205"></a>
-<span class="sourceLineNo">206</span> if (isFirst) {<a name="line.206"></a>
-<span class="sourceLineNo">207</span> WALProtos.WALHeader header = builder.build();<a name="line.207"></a>
-<span class="sourceLineNo">208</span> this.hasCompression = header.hasHasCompression() && header.getHasCompression();<a name="line.208"></a>
-<span class="sourceLineNo">209</span> this.hasTagCompression = header.hasHasTagCompression() && header.getHasTagCompression();<a name="line.209"></a>
-<span class="sourceLineNo">210</span> }<a name="line.210"></a>
-<span class="sourceLineNo">211</span> this.inputStream = stream;<a name="line.211"></a>
-<span class="sourceLineNo">212</span> this.walEditsStopOffset = this.fileLength;<a name="line.212"></a>
-<span class="sourceLineNo">213</span> long currentPosition = stream.getPos();<a name="line.213"></a>
-<span class="sourceLineNo">214</span> trailerPresent = setTrailerIfPresent();<a name="line.214"></a>
-<span class="sourceLineNo">215</span> this.seekOnFs(currentPosition);<a name="line.215"></a>
-<span class="sourceLineNo">216</span> if (LOG.isTraceEnabled()) {<a name="line.216"></a>
-<span class="sourceLineNo">217</span> LOG.trace("After reading the trailer: walEditsStopOffset: " + this.walEditsStopOffset<a name="line.217"></a>
-<span class="sourceLineNo">218</span> + ", fileLength: " + this.fileLength + ", " + "trailerPresent: " + trailerPresent);<a name="line.218"></a>
-<span class="sourceLineNo">219</span> }<a name="line.219"></a>
-<span class="sourceLineNo">220</span> <a name="line.220"></a>
-<span class="sourceLineNo">221</span> codecClsName = hdrCtxt.getCellCodecClsName();<a name="line.221"></a>
-<span class="sourceLineNo">222</span> <a name="line.222"></a>
-<span class="sourceLineNo">223</span> return hdrCtxt.getCellCodecClsName();<a name="line.223"></a>
-<span class="sourceLineNo">224</span> }<a name="line.224"></a>
-<span class="sourceLineNo">225</span><a name="line.225"></a>
-<span class="sourceLineNo">226</span> /**<a name="line.226"></a>
-<span class="sourceLineNo">227</span> * To check whether a trailer is present in a WAL, it seeks to position (fileLength -<a name="line.227"></a>
-<span class="sourceLineNo">228</span> * PB_WAL_COMPLETE_MAGIC.size() - Bytes.SIZEOF_INT). It reads the int value to know the size of<a name="line.228"></a>
-<span class="sourceLineNo">229</span> * the trailer, and checks whether the trailer is present at the end or not by comparing the last<a name="line.229"></a>
-<span class="sourceLineNo">230</span> * PB_WAL_COMPLETE_MAGIC.size() bytes. In case trailer is not present, it returns false;<a name="line.230"></a>
-<span class="sourceLineNo">231</span> * otherwise, sets the trailer and sets this.walEditsStopOffset variable up to the point just<a name="line.231"></a>
-<span class="sourceLineNo">232</span> * before the trailer.<a name="line.232"></a>
-<span class="sourceLineNo">233</span> * <ul><a name="line.233"></a>
-<span class="sourceLineNo">234</span> * The trailer is ignored in case:<a name="line.234"></a>
-<span class="sourceLineNo">235</span> * <li>fileLength is 0 or not correct (when file is under recovery, etc).<a name="line.235"></a>
-<span class="sourceLineNo">236</span> * <li>the trailer size is negative.<a name="line.236"></a>
-<span class="sourceLineNo">237</span> * </ul><a name="line.237"></a>
-<span class="sourceLineNo">238</span> * <p><a name="line.238"></a>
-<span class="sourceLineNo">239</span> * In case the trailer size > this.trailerMaxSize, it is read after a WARN message.<a name="line.239"></a>
-<span class="sourceLineNo">240</span> * @return true if a valid trailer is present<a name="line.240"></a>
-<span class="sourceLineNo">241</span> * @throws IOException<a name="line.241"></a>
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-<span class="sourceLineNo">243</span> private boolean setTrailerIfPresent() {<a name="line.243"></a>
-<span class="sourceLineNo">244</span> try {<a name="line.244"></a>
-<span class="sourceLineNo">245</span> long trailerSizeOffset = this.fileLength - (PB_WAL_COMPLETE_MAGIC.length + Bytes.SIZEOF_INT);<a name="line.245"></a>
-<span class="sourceLineNo">246</span> if (trailerSizeOffset <= 0) return false;// no trailer possible.<a name="line.246"></a>
-<span class="sourceLineNo">247</span> this.seekOnFs(trailerSizeOffset);<a name="line.247"></a>
-<span class="sourceLineNo">248</span> // read the int as trailer size.<a name="line.248"></a>
-<span class="sourceLineNo">249</span> int trailerSize = this.inputStream.readInt();<a name="line.249"></a>
-<span class="sourceLineNo">250</span> ByteBuffer buf = ByteBuffer.allocate(ProtobufLogReader.PB_WAL_COMPLETE_MAGIC.length);<a name="line.250"></a>
-<span class="sourceLineNo">251</span> this.inputStream.readFully(buf.array(), buf.arrayOffset(), buf.capacity());<a name="line.251"></a>
-<span class="sourceLineNo">252</span> if (!Arrays.equals(buf.array(), PB_WAL_COMPLETE_MAGIC)) {<a name="line.252"></a>
-<span class="sourceLineNo">253</span> LOG.trace("No trailer found.");<a name="line.253"></a>
-<span class="sourceLineNo">254</span> return false;<a name="line.254"></a>
-<span class="sourceLineNo">255</span> }<a name="line.255"></a>
-<span class="sourceLineNo">256</span> if (trailerSize < 0) {<a name="line.256"></a>
-<span class="sourceLineNo">257</span> LOG.warn("Invalid trailer Size " + trailerSize + ", ignoring the trailer");<a name="line.257"></a>
-<span class="sourceLineNo">258</span> return false;<a name="line.258"></a>
-<span class="sourceLineNo">259</span> } else if (trailerSize > this.trailerWarnSize) {<a name="line.259"></a>
-<span class="sourceLineNo">260</span> // continue reading after warning the user.<a name="line.260"></a>
-<span class="sourceLineNo">261</span> LOG.warn("Please investigate WALTrailer usage. Trailer size > maximum configured size : "<a name="line.261"></a>
-<span class="sourceLineNo">262</span> + trailerSize + " > " + this.trailerWarnSize);<a name="line.262"></a>
-<span class="sourceLineNo">263</span> }<a name="line.263"></a>
-<span class="sourceLineNo">264</span> // seek to the position where trailer starts.<a name="line.264"></a>
-<span class="sourceLineNo">265</span> long positionOfTrailer = trailerSizeOffset - trailerSize;<a name="line.265"></a>
-<span class="sourceLineNo">266</span> this.seekOnFs(positionOfTrailer);<a name="line.266"></a>
-<span class="sourceLineNo">267</span> // read the trailer.<a name="line.267"></a>
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