On Wed, Feb 15, 2017 at 1:13 AM, Junio C Hamano <gitster@xxxxxxxxx> wrote:
> Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx> writes:
>
>> All these warning() calls are preceded by a system call. Report the
>> actual error to help the user understand why we fail to remove
>> something.
>>
>> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx>
>> ---
>> v2 dances with errno
>
> Thanks.
>
>>
>> builtin/clean.c | 19 ++++++++++++++-----
>> 1 file changed, 14 insertions(+), 5 deletions(-)
>>
>> diff --git a/builtin/clean.c b/builtin/clean.c
>> index d6bc3aaae..3569736f6 100644
>> --- a/builtin/clean.c
>> +++ b/builtin/clean.c
>> @@ -154,6 +154,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
>> struct strbuf quoted = STRBUF_INIT;
>> struct dirent *e;
>> int res = 0, ret = 0, gone = 1, original_len = path->len, len;
>> + int saved_errno;
>> struct string_list dels = STRING_LIST_INIT_DUP;
>>
>> *dir_gone = 1;
>> @@ -173,9 +174,11 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
>> if (!dir) {
>> /* an empty dir could be removed even if it is unreadble */
>> res = dry_run ? 0 : rmdir(path->buf);
>> + saved_errno = errno;
>> if (res) {
>> quote_path_relative(path->buf, prefix, "ed);
>
> I think this part should be more like
>
> res = ... : rmdir(...);
> if (res) {
> int saved_errno = errno;
> ... do other things that can touch errno ...
> errno = saved_errno;
> ... now we know what the original error was ...
>
> The reason to store the errno in saved_errno here is not because we
> want to help code after "if (res) {...}", but the patch sent as-is
> gives that impression and is confusing to the readers.
>
> Perhaps all hunks of this patch share the same issue? I could
> locally amend, of course, but I'd like to double check before doing
> so myself---perhaps you did it this way for a good reason that I am
> missing?
One thing I like about putting saved_errno right next to the related
syscall is, the syscall is visible from the diff (previously some are
out of context). This is really minor though. I briefly thought of
introducing rmdir_errno() and friends that return -errno on error, so
we could do
res = ... : rmdir_errno(..);
if (res) {
errno = -res;
warning_errno(...);
}
But that's more work and the errno = -res is not particularly pleasing
to read. I'm fine with moving saved_errno in the error handling
blocks.
--
Duy