Mercurial > jhg
diff src/org/tmatesoft/hg/internal/DataAccessProvider.java @ 158:b413b16d10a5
Integer offsets and file length explictly, rather than casts throughout code. Inflater may benefit from total length hint, but shall calculate it by its own if needed
author | Artem Tikhomirov <tikhomirov.artem@gmail.com> |
---|---|
date | Wed, 09 Mar 2011 13:16:37 +0100 |
parents | d5268ca7715b |
children | 981f9f50bb6c |
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--- a/src/org/tmatesoft/hg/internal/DataAccessProvider.java Wed Mar 09 05:22:17 2011 +0100 +++ b/src/org/tmatesoft/hg/internal/DataAccessProvider.java Wed Mar 09 13:16:37 2011 +0100 @@ -23,6 +23,8 @@ import java.nio.MappedByteBuffer; import java.nio.channels.FileChannel; +import org.tmatesoft.hg.core.HgBadStateException; + /** * * @author Artem Tikhomirov @@ -48,16 +50,20 @@ } try { FileChannel fc = new FileInputStream(f).getChannel(); - if (fc.size() > mapioMagicBoundary) { + int flen = (int) fc.size(); + if (fc.size() - flen != 0) { + throw new HgBadStateException("Files greater than 2Gb are not yet supported"); + } + if (flen > mapioMagicBoundary) { // TESTS: bufLen of 1024 was used to test MemMapFileAccess - return new MemoryMapFileAccess(fc, fc.size(), mapioMagicBoundary); + return new MemoryMapFileAccess(fc, flen, mapioMagicBoundary); } else { // XXX once implementation is more or less stable, // may want to try ByteBuffer.allocateDirect() to see // if there's any performance gain. boolean useDirectBuffer = false; - // TESTS: bufferSize of 100 was used to check buffer underflow states when readBytes reads chunks bigger than bufSize - return new FileAccess(fc, fc.size(), bufferSize, useDirectBuffer); + // TESTS: bufferSize of 100 was used to check buffer underflow states when readBytes reads chunks bigger than bufSize + return new FileAccess(fc, flen, bufferSize, useDirectBuffer); } } catch (IOException ex) { // unlikely to happen, we've made sure file exists. @@ -69,12 +75,12 @@ // DOESN'T WORK YET private static class MemoryMapFileAccess extends DataAccess { private FileChannel fileChannel; - private final long size; + private final int size; private long position = 0; // always points to buffer's absolute position in the file private final int memBufferSize; private MappedByteBuffer buffer; - public MemoryMapFileAccess(FileChannel fc, long channelSize, int /*long?*/ bufferSize) { + public MemoryMapFileAccess(FileChannel fc, int channelSize, int /*long?*/ bufferSize) { fileChannel = fc; size = channelSize; memBufferSize = bufferSize; @@ -86,7 +92,7 @@ } @Override - public long length() { + public int length() { return size; } @@ -97,7 +103,7 @@ } @Override - public void seek(long offset) { + public void seek(int offset) { assert offset >= 0; // offset may not necessarily be further than current position in the file (e.g. rewind) if (buffer != null && /*offset is within buffer*/ offset >= position && (offset - position) < buffer.limit()) { @@ -181,14 +187,14 @@ // (almost) regular file access - FileChannel and buffers. private static class FileAccess extends DataAccess { private FileChannel fileChannel; - private final long size; + private final int size; private ByteBuffer buffer; - private long bufferStartInFile = 0; // offset of this.buffer in the file. + private int bufferStartInFile = 0; // offset of this.buffer in the file. - public FileAccess(FileChannel fc, long channelSize, int bufferSizeHint, boolean useDirect) { + public FileAccess(FileChannel fc, int channelSize, int bufferSizeHint, boolean useDirect) { fileChannel = fc; size = channelSize; - final int capacity = size < bufferSizeHint ? (int) size : bufferSizeHint; + final int capacity = size < bufferSizeHint ? size : bufferSizeHint; buffer = useDirect ? ByteBuffer.allocateDirect(capacity) : ByteBuffer.allocate(capacity); buffer.flip(); // or .limit(0) to indicate it's empty } @@ -199,7 +205,7 @@ } @Override - public long length() { + public int length() { return size; } @@ -210,7 +216,7 @@ } @Override - public void seek(long offset) throws IOException { + public void seek(int offset) throws IOException { if (offset > size) { throw new IllegalArgumentException(); }