Binary and CR-LF detection: lone CRs -> binary

C git considers not only files containing NUL bytes as binary but also
files containing lone CRs. Implement this also for JGit.

C git additionally counts printable vs. non-printable characters and
considers files that have non_printable_count > printable_count / 128
also as binary. This is not implemented because such counting probably
only makes sense if one looks at the full file or blob content. The
Auto[CR]LF* streams in JGit look only at the first few KiB of a stream
in order not to buffer too much.

For the C git implementation, see [1].

[1] https://github.com/git/git/blob/7e27bd589d/convert.c#L35

Bug: 576971
Change-Id: Ia169b59bdbf1477f32ee2014eeb8406f81d4b1ab
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

2 files changed, 3 insertions, 3 deletions

diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
index cd5d8f1bfe..a63387c24c 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
@@ -173,7 +173,7 @@ class DiffAlgorithms extends TextBuiltin {
 					} catch (LargeObjectException tooBig) {
 						continue;
 					}
-					if (RawText.isBinary(raw0))
+					if (RawText.isBinary(raw0, raw0.length, true))
 						continue;
 
 					byte[] raw1;
@@ -183,7 +183,7 @@ class DiffAlgorithms extends TextBuiltin {
 					} catch (LargeObjectException tooBig) {
 						continue;
 					}
-					if (RawText.isBinary(raw1))
+					if (RawText.isBinary(raw1, raw1.length, true))
 						continue;
 
 					RawText txt0 = new RawText(raw0);
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
index f777f277f4..1ca3034f4f 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
@@ -286,7 +286,7 @@ class TextHashFunctions extends TextBuiltin {
 					continue;
 				}
 
-				if (RawText.isBinary(raw))
+				if (RawText.isBinary(raw, raw.length, true))
 					continue;
 
 				RawText txt = new RawText(raw);