# [JGIT PATCH 2/2] improve the handling of empty lines 2 messages from 2009-09-02 to 2009-09-02. Participants: Mark Struberg. Thread: https://gitlist.dev/t/20827 ## Mark Struberg, 2009-09-02 18:00 Subject: [JGIT PATCH 1/2] fixed error in whitespace handling of RefDatabase#readLine Message-ID: <1251914428-1687-1-git-send-email-struberg@yahoo.de> URL: https://gitlist.dev/e/1251914428-1687-1-git-send-email-struberg%40yahoo.de ``` jgit fails with "cannot checkout; no HEAD advertised by remote" in guessHEAD on some repositories. JGIT used to work on my test repo for the maven-scm-providers-git until a few weeks. I tracked it down with git bisect and found commit 72b1f0d334729a49cc52e4762093148be62bea39 to be the bad one. I glimpsed at the code and it appears that the new code in RefDatabase#readLine is not Windows CR+LF aware. (This hits me although I use Linux because our SVN at apache.org seems to have it stored with CR+LF.) Fixed by subsequently removing all Character.isWhitespaceChar() from the end of the buffer Signed-off-by: Mark Struberg --- .../src/org/spearce/jgit/lib/RefDatabase.java | 6 +++++- 1 files changed, 5 insertions(+), 1 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 ba4b654..477dc62 100644 --- a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java +++ b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java @@ -500,8 +500,12 @@ private static String readLine(final File file) int n = buf.length; if (n == 0) return null; - if (buf[n - 1] == '\n') + + // remove trailing whitespaces + while (n > 0 && Character.isWhitespace(buf[n - 1])) { n--; + } + return RawParseUtils.decode(buf, 0, n); } -- 1.6.2.5 ``` ## Mark Struberg, 2009-09-02 18:00 Subject: [JGIT PATCH 2/2] improve the handling of empty lines Message-ID: <1251914428-1687-2-git-send-email-struberg@yahoo.de> URL: https://gitlist.dev/e/1251914428-1687-2-git-send-email-struberg%40yahoo.de In-Reply-To: <1251914428-1687-1-git-send-email-struberg@yahoo.de> ``` Move the 'empty-line' check in RefDatabase#readLine down a bit after we removed all the whitespaces. This way we consistently return null regardless if the line is empty or if it does only contain whitespaces. Signed-off-by: Mark Struberg --- .../src/org/spearce/jgit/lib/RefDatabase.java | 7 ++++--- 1 files changed, 4 insertions(+), 3 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 477dc62..acc835b 100644 --- a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java +++ b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java @@ -498,14 +498,15 @@ private static String readLine(final File file) throws FileNotFoundException, IOException { final byte[] buf = NB.readFully(file, 4096); int n = buf.length; - if (n == 0) - return null; // remove trailing whitespaces while (n > 0 && Character.isWhitespace(buf[n - 1])) { n--; } - + + if (n == 0) + return null; + return RawParseUtils.decode(buf, 0, n); } -- 1.6.2.5 ```