git/list[1] front-page[2] threads[3] people[4] search[5] about
 

git patch-id fails on long lines

From
APAndrew Pimlott <andrew@pimlott.net>
Date
Sep 20, 2011, 18:07 UTC
Message-ID
<1316541771-sup-9996@pimlott.net>

In patch-id.c, get_one_patchid uses a fixed 1000-char buffer to read a line.[1] This causes incorrect results on longer lines. Pasted below is a git commit (from git show) that demonstrates the problem. The result of running git patch-id on this commit is:

9220f380851be9cab1a760430e3be096dcbee8c6 9b96b6fde8f7df791a1490ae18e1fa75fbab3262 74b8ede07628a574fd586624e0c77a4b6c9967e0 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

The commit:
commit 9b96b6fde8f7df791a1490ae18e1fa75fbab3262
Author: Andrew Pimlott <andrew@pimlott.net>
Date:   Tue Sep 20 10:53:25 2011 -0700
    2
diff --git a/a b/a
index e69de29..2e6adac 100644
--- a/a
+++ b/a
@@ -0,0 +1 @@
+aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
diff --git a/b b/b
index e69de29..1425fcc 100644
--- a/b
+++ b/b
@@ -0,0 +1 @@
+b

Andrew

[1] https://github.com/git/git/blob/master/builtin/patch-id.c
Next: Junio C Hamano
Message 1 of 5 in “git patch-id fails on long lines”
  1. Andrew PimlottSep 20, 2011
  2. Junio C HamanoSep 20, 2011
  3. patch-id.c: use strbuf instead of a fixed bufferMichael Schubert, Sep 21, 2011
  4. Jeff KingSep 22, 2011
  5. Jeff KingSep 20, 2011

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.