diff mbox series

[1/1] add: respect `--ignore-errors` when `lstat()` reports errors

Message ID fd022f88f54f6cf0feb61965b2dc47bca64c0937.1572127149.git.gitgitgadget@gmail.com (mailing list archive)
State New, archived
Headers show
Series add: respect --ignore-errors when lstat() reports errors | expand

Commit Message

Johannes Schindelin via GitGitGadget Oct. 26, 2019, 9:59 p.m. UTC 
From: qusielle <31454380+qusielle@users.noreply.github.com>

"git add --ignore-errors" command fails immediately when lstat returns
an error, despite the ignore errors' flag is enabled.

There could be files that triggers an error on stat(), when other files
proceed correctly.
Issue can be reproduced when running git under Cygwin and some target files
have utf-8 long names (200+ utf chars). Windows can handle them, but all
operations on them failed under Cygwin.
Issue can not be reproduced with usual latin/numeric only names.
For example, create a file with 220 'й' letters by Windows Explorer,
then in Cygwin:

 # Here and below "ййй..." means the line of й copied 220 times.
$ echo -n 'ййй...' | wc -c  # check the real size
440

$ ls -la
ls: cannot access 'ййй...'$'\320': No such file or directory
-????????? ? ?              ?        ?            ? 'ййй...'$'\320'

$ ls й*
ls: cannot access 'ййй...'$'\320': No such file or directory

$ stat й*
stat: cannot stat 'ййй...'$'\320': No such file or directory

In my perspective, it's okay to skip these problematic files when ignore
error flag is specified, but official Git terminates entire git add command
when such files come up. But with proposed patch it is the desired behavior:

$ git add --ignore-errors .
error: ййй... can only add regular files, symbolic links or git-directories
 # All other files have been added correctly.

Signed-off-by: Qusielle <qusielle@gmail.com>
---
 read-cache.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Junio C Hamano Oct. 28, 2019, 2:03 a.m. UTC | #1 
"qusielle via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: qusielle <31454380+qusielle@users.noreply.github.com>
>
> "git add --ignore-errors" command fails immediately when lstat returns
> an error, despite the ignore errors' flag is enabled.
> ...
> diff --git a/read-cache.c b/read-cache.c
> index 133f790fa4..67237ecd29 100644
> --- a/read-cache.c
> +++ b/read-cache.c
> @@ -801,7 +801,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
>  int add_file_to_index(struct index_state *istate, const char *path, int flags)
>  {
>  	struct stat st;
> -	if (lstat(path, &st))
> +	if (lstat(path, &st) && !(flags & ADD_CACHE_IGNORE_ERRORS))
>  		die_errno(_("unable to stat '%s'"), path);
>  	return add_to_index(istate, path, &st, flags);
>  }

The only callers of this function that matter calls it and then
responds to an error return like so:

(in builtin/add.c::update_callback())

	if (add_file_to_index(&the_index, path,	data->flags)) {
		if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
			die(_("updating files failed"));


(in builtin/add.c::add_files(), where ignore_add_errors was used to
set the ADD_CACHE_IGNORE_ERRORS to flags in its caller)

	if (add_file_to_index(&the_index, dir->entries[i]->name, flags)) {
		if (!ignore_add_errors)
			die(_("adding files failed"));

So you correctly identified what is the right place to fix.  We
should not "die_errno()"; we should give the control back to the
caller instead.

But after a failed stat, the code with your patch still calls
add_to_index() using the now undefined stat data, which would
contaminate the in-core index with wrong data.  

I think we should instead return without touching the index for the
path we had trouble lstat()ing.

IOW

	if (lstat(path, &st)) {
		if (flags & ADD_CACHE_IGNORE_ERRORS)
			return -1;
		else
			die_errno(_("unable to ..."));
	}
	return add_to_index(...);
qusielle@gmail.com Nov. 3, 2019, 8:17 p.m. UTC | #2 
Dear Junio,

Thank you for reviewing my patch. I completely agree with you, that 
add_to_index() should not be called with undefined data.

I will amend patch now with proposed changes.

Thank you!

Best regards,
Qusielle


On 28.10.2019 03:03, Junio C Hamano wrote:
> "qusielle via GitGitGadget" <gitgitgadget@gmail.com> writes:
>
>> From: qusielle <31454380+qusielle@users.noreply.github.com>
>>
>> "git add --ignore-errors" command fails immediately when lstat returns
>> an error, despite the ignore errors' flag is enabled.
>> ...
>> diff --git a/read-cache.c b/read-cache.c
>> index 133f790fa4..67237ecd29 100644
>> --- a/read-cache.c
>> +++ b/read-cache.c
>> @@ -801,7 +801,7 @@ int add_to_index(struct index_state *istate, const char *path, struct stat *st,
>>   int add_file_to_index(struct index_state *istate, const char *path, int flags)
>>   {
>>   	struct stat st;
>> -	if (lstat(path, &st))
>> +	if (lstat(path, &st) && !(flags & ADD_CACHE_IGNORE_ERRORS))
>>   		die_errno(_("unable to stat '%s'"), path);
>>   	return add_to_index(istate, path, &st, flags);
>>   }
> The only callers of this function that matter calls it and then
> responds to an error return like so:
>
> (in builtin/add.c::update_callback())
>
> 	if (add_file_to_index(&the_index, path,	data->flags)) {
> 		if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
> 			die(_("updating files failed"));
>
>
> (in builtin/add.c::add_files(), where ignore_add_errors was used to
> set the ADD_CACHE_IGNORE_ERRORS to flags in its caller)
>
> 	if (add_file_to_index(&the_index, dir->entries[i]->name, flags)) {
> 		if (!ignore_add_errors)
> 			die(_("adding files failed"));
>
> So you correctly identified what is the right place to fix.  We
> should not "die_errno()"; we should give the control back to the
> caller instead.
>
> But after a failed stat, the code with your patch still calls
> add_to_index() using the now undefined stat data, which would
> contaminate the in-core index with wrong data.
>
> I think we should instead return without touching the index for the
> path we had trouble lstat()ing.
>
> IOW
>
> 	if (lstat(path, &st)) {
> 		if (flags & ADD_CACHE_IGNORE_ERRORS)
> 			return -1;
> 		else
> 			die_errno(_("unable to ..."));
> 	}
> 	return add_to_index(...);
>
>
diff mbox series

Patch

diff --git a/read-cache.c b/read-cache.c
index 133f790fa4..67237ecd29 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -801,7 +801,7 @@  int add_to_index(struct index_state *istate, const char *path, struct stat *st,
 int add_file_to_index(struct index_state *istate, const char *path, int flags)
 {
 	struct stat st;
-	if (lstat(path, &st))
+	if (lstat(path, &st) && !(flags & ADD_CACHE_IGNORE_ERRORS))
 		die_errno(_("unable to stat '%s'"), path);
 	return add_to_index(istate, path, &st, flags);
 }