[PATCH] erofs-utils: fix `--blobdev=X`

[Hongbo Li]

On 2025/4/27 15:17, Gao Xiang wrote:
> 
> 
> On 2025/4/27 15:04, Hongbo Li wrote:
>>
>>
>> On 2025/4/27 10:56, Gao Xiang wrote:
> 
> ...
> 
>>>>> diff --git a/lib/blobchunk.c b/lib/blobchunk.c
>>>>> index e6386d6..301f46a 100644
>>>>> --- a/lib/blobchunk.c
>>>>> +++ b/lib/blobchunk.c
>>>>> @@ -627,7 +627,8 @@ int erofs_blob_init(const char *blobfile_path, 
>>>>> erofs_off_t chunksize)
>>>>>           blobfile = erofs_tmpfile();
>>>>>           multidev = false;
>>>>>       } else {
>>>>> -        blobfile = open(blobfile_path, O_WRONLY | O_BINARY);
>>>>> +        blobfile = open(blobfile_path, O_WRONLY | O_CREAT |
>>>>> +                        O_TRUNC | O_BINARY, 0666);
>>>> To maintain consistency, is it better to set the default permission 
>>>> to 0644?
>>>
>>> I tend to switch all modes to 0666 around the codebase
>>> in the future, since umask(022) will mask them into 0644.
>>>
>> but 0644 can clearly show which permissions are set (the default umask 
>> 022 won't change anything). Or if we need to enforce a specific mode, 
>> can we umask to 0 at the beginning instead of relying on the default 
>> umask?
> 
> see fopen(3): https://man7.org/linux/man-pages/man3/fopen.3.html
> 
> In short, I'd like to change all 0644 to 0666 since
> there is no reason to mask off other permissions
> unless umask is also effective.
> 
> Or do you have other concerns?

ok, I have not other concerns.

Reviewed-by: Hongbo Li <lihongbo22 at huawei.com>

> 
>>
>> By the way, I have another doubt (just occurred to me when seeing 
>> O_TRUNC, though it might be unrelated to this change): the chunk-based 
>> format can't be used together with the "--increase" option. Should we 
>> add a warning for that?
> 
> Why?
> 
> Thanks,
> Gao Xiang
> 
>>
>> Thanks,
>> Hongbo
>>
>>> Thanks,
>>> Gao Xiang
>