threads / bug / 24775

BUG?: git-apply sometimes says "corrupt patch" when adding single lines

Subject: BUG?: git-apply sometimes says "corrupt patch" when adding single lines

## tl;dr

5 messages between Aug 17, 2010 and Aug 18, 2010.

replies: 4people: 3as markdown or json

Tor Arvid Lund· Aug 17, 2010, 23:27 UTC · lore

Hi.

I often use git-gui when staging commits, and I noticed that if the file I'm working with has a:

\ No newline at end of file

... as the last line of the diff, and I try to "Stage lines for commit", then git-gui (or really git-apply, as I understand it) says that I have a "corrupt patch at line <so-and-so>".

I don't really know the git-gui code or the git C code well, but it seems that I got around the error with this small patch:

diff --git a/builtin/apply.c b/builtin/apply.c
index 12ef9ea..124791f 100644
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -1335,6 +1335,8 @@ static int parse_fragment(char *line, unsigned long size,
 		 * l10n of "\ No newline..." is at least that long.
 		 */
 		case '\\':
+			if (newlines == oldlines == 1)
+				newlines = oldlines = 0;
 			if (len < 12 || memcmp(line, "\\ ", 2))
 				return -1;
 			break;




Is this a bug? Or is it maybe git-gui that sends something wrong to
git-apply? I don't know... :-/

(I'm using msysGit on Windows, if that matters)

-Tor Arvid-

Jonathan Nieder· Aug 17, 2010, 23:43 UTC · re: Tor Arvid Lund · lore

Re: BUG?: git-apply sometimes says "corrupt patch" when adding single lines

Tor Arvid Lund wrote:

Show 12 quoted lines

> I don't really know the git-gui code or the git C code well, but it
> seems that I got around the error with this small patch:
> 
> diff --git a/builtin/apply.c b/builtin/apply.c
> index 12ef9ea..124791f 100644
> --- a/builtin/apply.c
> +++ b/builtin/apply.c
> @@ -1335,6 +1335,8 @@ static int parse_fragment(char *line, unsigned long size,
>  		 * l10n of "\ No newline..." is at least that long.
>  		 */
>  		case '\\':
> +			if (newlines == oldlines == 1)

[...]

Heh. This code is a roundabout way to say "if (newlines == oldlines)", rather than "if (newlines == 1 && oldlines == 1)" that might have been intended.

Unfortunately I do not have any more insight than that. If you can give an example reproducing this with git apply from the command line, that would be very helpful.

Thanks, Jonathan

Tor Arvid Lund· Aug 18, 2010, 01:37 UTC · re: Jonathan Nieder · lore

Re: BUG?: git-apply sometimes says "corrupt patch" when adding single lines

On Wed, Aug 18, 2010 at 1:43 AM, Jonathan Nieder <jrnieder@gmail.com> wrote:

Show 19 quoted lines

> Tor Arvid Lund wrote:
>
>> I don't really know the git-gui code or the git C code well, but it
>> seems that I got around the error with this small patch:
>>
>> diff --git a/builtin/apply.c b/builtin/apply.c
>> index 12ef9ea..124791f 100644
>> --- a/builtin/apply.c
>> +++ b/builtin/apply.c
>> @@ -1335,6 +1335,8 @@ static int parse_fragment(char *line, unsigned long size,
>>                * l10n of "\ No newline..." is at least that long.
>>                */
>>               case '\\':
>> +                     if (newlines == oldlines == 1)
> [...]
>
> Heh.  This code is a roundabout way to say "if (newlines == oldlines)",
> rather than "if (newlines == 1 && oldlines == 1)" that might have been
> intended.

Right you are, good sir ;-)

> Unfortunately I do not have any more insight than that.  If you can
> give an example reproducing this with git apply from the command
> line, that would be very helpful.

I'll try to do that tomorrow.. My brain needs sleep before it will function :)

-Tor Arvid-

Johannes Sixt· Aug 18, 2010, 07:29 UTC · re: Tor Arvid Lund · lore

Re: BUG?: git-apply sometimes says "corrupt patch" when adding single lines

Am 8/18/2010 1:27, schrieb Tor Arvid Lund:

Show 11 quoted lines

> I often use git-gui when staging commits, and I noticed that if the
> file I'm working with has a:
> 
> \ No newline at end of file
> 
> ... as the last line of the diff, and I try to "Stage lines for
> commit", then git-gui (or really git-apply, as I understand it) says
> that I have a "corrupt patch at line <so-and-so>".
> 
> Is this a bug? Or is it maybe git-gui that sends something wrong to
> git-apply? I don't know... :-/

This is really a bug in git-gui, not in git-apply: The big while loop in lib/diff.tcl, function apply_range_or_line, must be taught about "\ No newline...".

-- Hannes

Tor Arvid Lund· Aug 18, 2010, 09:15 UTC · re: Johannes Sixt · lore

Re: BUG?: git-apply sometimes says "corrupt patch" when adding single lines

On Wed, Aug 18, 2010 at 9:29 AM, Johannes Sixt <j.sixt@viscovery.net> wrote:

Show 16 quoted lines

> Am 8/18/2010 1:27, schrieb Tor Arvid Lund:
>> I often use git-gui when staging commits, and I noticed that if the
>> file I'm working with has a:
>>
>> \ No newline at end of file
>>
>> ... as the last line of the diff, and I try to "Stage lines for
>> commit", then git-gui (or really git-apply, as I understand it) says
>> that I have a "corrupt patch at line <so-and-so>".
>>
>> Is this a bug? Or is it maybe git-gui that sends something wrong to
>> git-apply? I don't know... :-/
>
> This is really a bug in git-gui, not in git-apply: The big while loop in
> lib/diff.tcl, function apply_range_or_line, must be taught about "\ No
> newline...".

Ok, thanks for tracking it down. I suspected this, since the tests for git-apply seemed to have example patches for "\ No newline...". Ultimately, this doesn't scratch me enough that I want to learn (or guess) how to fix the Tcl stuff...

-Tor Arvid-