When we want the entire file contents and its likely a very small
file (e.g. a ref, configuration file) NB.readFully(File) is an
easier method to get the content then using FileInputStream from
application code.
When looking at a file that we believe should contain only a SHA-1
or be a symbolic ref to another file within this repository,
we use a maximum read cap of 4096 bytes for the slurp, so that
we don't accidentally allocate a very large buffer and blow the
JVM heap up. This reasonableness cap is particularly important
for the RepositoryCache.FileKey.isGitRepository() test logic, in
case it comes across a file called HEAD that isn't really part of
a Git repository.
Signed-off-by: Shawn O. Pearce <spearce@xxxxxxxxxxx>
---
Due to the patch to RepositoryCache here, this applies on top of
my other 11 patch series that introduced the class.
.../src/org/spearce/jgit/lib/RefDatabase.java | 15 +++--
.../src/org/spearce/jgit/lib/ReflogReader.java | 32 ++++--------
.../src/org/spearce/jgit/lib/RepositoryCache.java | 20 +++----
.../org/spearce/jgit/lib/UnpackedObjectLoader.java | 15 +-----
org.spearce.jgit/src/org/spearce/jgit/util/NB.java | 52 ++++++++++++++++++++
5 files changed, 81 insertions(+), 53 deletions(-)
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
index 383877f..f7751c4 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
@@ -52,6 +52,8 @@
import org.spearce.jgit.errors.ObjectWritingException;
import org.spearce.jgit.lib.Ref.Storage;
import org.spearce.jgit.util.FS;
+import org.spearce.jgit.util.NB;
+import org.spearce.jgit.util.RawParseUtils;
class RefDatabase {
private static final String REFS_SLASH = "refs/";
@@ -494,12 +496,13 @@ protected void writeFile(String name, byte[] content) throws IOException {
private static String readLine(final File file)
throws FileNotFoundException, IOException {
- final BufferedReader br = openReader(file);
- try {
- return br.readLine();
- } finally {
- br.close();
- }
+ final byte[] buf = NB.readFully(file, 4096);
+ int n = buf.length;
+ if (n == 0)
+ return null;
+ if (buf[n - 1] == '\n')
+ n--;
+ return RawParseUtils.decode(buf, 0, n);
}
private static BufferedReader openReader(final File fileLocation)
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/ReflogReader.java b/org.spearce.jgit/src/org/spearce/jgit/lib/ReflogReader.java
index e86a723..5f2d28c 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/ReflogReader.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/ReflogReader.java
@@ -37,7 +37,6 @@
package org.spearce.jgit.lib;
import java.io.File;
-import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
@@ -157,31 +156,20 @@ public Entry getLastEntry() throws IOException {
* @throws IOException
*/
public List<Entry> getReverseEntries(int max) throws IOException {
- FileInputStream fileInputStream;
+ final byte[] log;
try {
- fileInputStream = new FileInputStream(logName);
+ log = NB.readFully(logName);
} catch (FileNotFoundException e) {
return Collections.emptyList();
}
- try {
- long logSize = fileInputStream.getChannel().size();
- if (logSize > Integer.MAX_VALUE) {
- // implementation limit, will suck with smaller files too
- throw new IOException("Cannot handle reflog larger than "
- + Integer.MAX_VALUE + " bytes");
- }
- byte[] log = new byte[(int) logSize];
- NB.readFully(fileInputStream, log, 0, log.length);
- int rs = RawParseUtils.prevLF(log, log.length);
- List<Entry> ret = new ArrayList<Entry>();
- while (rs >= 0 && max-- > 0) {
- rs = RawParseUtils.prevLF(log, rs);
- Entry entry = new Entry(log, rs < 0 ? 0 : rs + 2);
- ret.add(entry);
- }
- return ret;
- } finally {
- fileInputStream.close();
+
+ int rs = RawParseUtils.prevLF(log, log.length);
+ List<Entry> ret = new ArrayList<Entry>();
+ while (rs >= 0 && max-- > 0) {
+ rs = RawParseUtils.prevLF(log, rs);
+ Entry entry = new Entry(log, rs < 0 ? 0 : rs + 2);
+ ret.add(entry);
}
+ return ret;
}
}
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/RepositoryCache.java b/org.spearce.jgit/src/org/spearce/jgit/lib/RepositoryCache.java
index 50b4330..5f90b55 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/RepositoryCache.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/RepositoryCache.java
@@ -37,11 +37,8 @@
package org.spearce.jgit.lib;
-import java.io.BufferedReader;
import java.io.File;
-import java.io.FileInputStream;
import java.io.IOException;
-import java.io.InputStreamReader;
import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import java.util.Iterator;
@@ -50,6 +47,8 @@
import org.spearce.jgit.errors.RepositoryNotFoundException;
import org.spearce.jgit.util.FS;
+import org.spearce.jgit.util.NB;
+import org.spearce.jgit.util.RawParseUtils;
/** Cache of active {@link Repository} instances. */
public class RepositoryCache {
@@ -341,14 +340,13 @@ private static boolean isValidHead(final File head) {
private static String readFirstLine(final File head) {
try {
- final BufferedReader br = new BufferedReader(
- new InputStreamReader(new FileInputStream(head),
- Constants.CHARSET));
- try {
- return br.readLine();
- } finally {
- br.close();
- }
+ final byte[] buf = NB.readFully(head, 4096);
+ int n = buf.length;
+ if (n == 0)
+ return null;
+ if (buf[n - 1] == '\n')
+ n--;
+ return RawParseUtils.decode(buf, 0, n);
} catch (IOException e) {
return null;
}
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/UnpackedObjectLoader.java b/org.spearce.jgit/src/org/spearce/jgit/lib/UnpackedObjectLoader.java
index e2de41c..b5abeb9 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/UnpackedObjectLoader.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/UnpackedObjectLoader.java
@@ -39,7 +39,6 @@
package org.spearce.jgit.lib;
import java.io.File;
-import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.zip.DataFormatException;
@@ -74,19 +73,7 @@
*/
public UnpackedObjectLoader(final File path, final AnyObjectId id)
throws IOException {
- this(readCompressed(path), id);
- }
-
- private static byte[] readCompressed(final File path)
- throws FileNotFoundException, IOException {
- final FileInputStream in = new FileInputStream(path);
- try {
- final byte[] compressed = new byte[(int) in.getChannel().size()];
- NB.readFully(in, compressed, 0, compressed.length);
- return compressed;
- } finally {
- in.close();
- }
+ this(NB.readFully(path), id);
}
/**
diff --git a/org.spearce.jgit/src/org/spearce/jgit/util/NB.java b/org.spearce.jgit/src/org/spearce/jgit/util/NB.java
index 032997f..17b3398 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/util/NB.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/util/NB.java
@@ -38,6 +38,9 @@
package org.spearce.jgit.util;
import java.io.EOFException;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
@@ -46,6 +49,55 @@
/** Conversion utilities for network byte order handling. */
public final class NB {
/**
+ * Read an entire local file into memory as a byte array.
+ *
+ * @param path
+ * location of the file to read.
+ * @return complete contents of the requested local file.
+ * @throws FileNotFoundException
+ * the file does not exist.
+ * @throws IOException
+ * the file exists, but its contents cannot be read.
+ */
+ public static final byte[] readFully(final File path)
+ throws FileNotFoundException, IOException {
+ return readFully(path, Integer.MAX_VALUE);
+ }
+
+ /**
+ * Read an entire local file into memory as a byte array.
+ *
+ * @param path
+ * location of the file to read.
+ * @param max
+ * maximum number of bytes to read, if the file is larger than
+ * this limit an IOException is thrown.
+ * @return complete contents of the requested local file.
+ * @throws FileNotFoundException
+ * the file does not exist.
+ * @throws IOException
+ * the file exists, but its contents cannot be read.
+ */
+ public static final byte[] readFully(final File path, final int max)
+ throws FileNotFoundException, IOException {
+ final FileInputStream in = new FileInputStream(path);
+ try {
+ final long sz = in.getChannel().size();
+ if (sz > max)
+ throw new IOException("File is too large: " + path);
+ final byte[] buf = new byte[(int) sz];
+ readFully(in, buf, 0, buf.length);
+ return buf;
+ } finally {
+ try {
+ in.close();
+ } catch (IOException ignored) {
+ // ignore any close errors, this was a read only stream
+ }
+ }
+ }
+
+ /**
* Read the entire byte array into memory, or throw an exception.
*
* @param fd
--
1.6.4.rc1.186.g60aa0c
--
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