[RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[Sidong Yang]

Remove a code that inserting new line in fmt_end() for text mode.
Old code made a failure in fstest btrfs/006.

Signed-off-by: Sidong Yang <realwakka@gmail.com>
---
Hi, I've just read mail that Filipe written that some failure about fstest.
I'm worried about this patch makes other problem. So make it RFC. Thanks.
---
 common/format-output.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/common/format-output.c b/common/format-output.c
index f5b12548..96e0dfef 100644
--- a/common/format-output.c
+++ b/common/format-output.c
@@ -124,9 +124,7 @@ void fmt_end(struct format_ctx *fctx)
 
 	/* Close, no continuation to print */
 
-	if (bconf.output_format & CMD_FORMAT_TEXT)
-		putchar('\n');
-	else if (bconf.output_format & CMD_FORMAT_JSON) {
+	if (bconf.output_format & CMD_FORMAT_JSON) {
 		fmt_dec_depth(fctx);
 		fmt_separator(fctx);
 		printf("}\n");
-- 
2.25.1

Re: [RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[Filipe Manana]

On Tue, Feb 16, 2021 at 4:28 PM Sidong Yang <realwakka@gmail.com> wrote:
>
> Remove a code that inserting new line in fmt_end() for text mode.
> Old code made a failure in fstest btrfs/006.
>
> Signed-off-by: Sidong Yang <realwakka@gmail.com>
> ---
> Hi, I've just read mail that Filipe written that some failure about fstest.
> I'm worried about this patch makes other problem. So make it RFC. Thanks.

Fixes the test failure indeed, thanks!

> ---
>  common/format-output.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/common/format-output.c b/common/format-output.c
> index f5b12548..96e0dfef 100644
> --- a/common/format-output.c
> +++ b/common/format-output.c
> @@ -124,9 +124,7 @@ void fmt_end(struct format_ctx *fctx)
>
>         /* Close, no continuation to print */
>
> -       if (bconf.output_format & CMD_FORMAT_TEXT)
> -               putchar('\n');
> -       else if (bconf.output_format & CMD_FORMAT_JSON) {
> +       if (bconf.output_format & CMD_FORMAT_JSON) {
>                 fmt_dec_depth(fctx);
>                 fmt_separator(fctx);
>                 printf("}\n");
> --
> 2.25.1
>


-- 
Filipe David Manana,

“Whether you think you can, or you think you can't — you're right.”

Re: [RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[David Sterba]

On Tue, Feb 16, 2021 at 04:28:40PM +0000, Sidong Yang wrote:
> Remove a code that inserting new line in fmt_end() for text mode.
> Old code made a failure in fstest btrfs/006.
> 
> Signed-off-by: Sidong Yang <realwakka@gmail.com>
> ---
> Hi, I've just read mail that Filipe written that some failure about fstest.
> I'm worried about this patch makes other problem. So make it RFC. Thanks.

I found the discussion under the device stats patch adding json, the
added line was known and "hopefully not causing problems", but the
fstests seem to notice.

I think we can fix that by removing the fmt_end newline but we also need
to update how the fmt_print is done for the text output. Ie. for json
there are some strict rules for line continuations  (",") but for the
textual output, each line ended by "\n" right away, without delaying
that to the next fmt_* call should work.

Re: [RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[Sidong Yang]

On Fri, Feb 19, 2021 at 10:56:11PM +0100, David Sterba wrote:
> On Tue, Feb 16, 2021 at 04:28:40PM +0000, Sidong Yang wrote:
> > Remove a code that inserting new line in fmt_end() for text mode.
> > Old code made a failure in fstest btrfs/006.
> > 
> > Signed-off-by: Sidong Yang <realwakka@gmail.com>
> > ---
> > Hi, I've just read mail that Filipe written that some failure about fstest.
> > I'm worried about this patch makes other problem. So make it RFC. Thanks.
> 
> I found the discussion under the device stats patch adding json, the
> added line was known and "hopefully not causing problems", but the
> fstests seem to notice.
> 
> I think we can fix that by removing the fmt_end newline but we also need
> to update how the fmt_print is done for the text output. Ie. for json
> there are some strict rules for line continuations  (",") but for the
> textual output, each line ended by "\n" right away, without delaying
> that to the next fmt_* call should work.

You mean that if this patch applied and the code prints device stats for
text format manually replaced to fmt_print(), there is no last new line
for text output? fmt_print() prints new line before print some value now.
I think that it should prints new line at the end of each fmt_print().
like below

diff --git a/common/format-output.c b/common/format-output.c
index f5b12548..9a9f5bf7 100644
--- a/common/format-output.c
+++ b/common/format-output.c
@@ -242,7 +239,6 @@ void fmt_print(struct format_ctx *fctx, const char* key, ...)
                const bool print_colon = row->out_text[0];
                int len;
 
-               putchar('\n');
                fmt_indent1(fctx->indent);
                len = strlen(row->out_text);
 
@@ -312,6 +308,8 @@ void fmt_print(struct format_ctx *fctx, const char* key, ...)
        }
 
        fmt_end_value(fctx, row);
+       if (bconf.output_format == CMD_FORMAT_TEXT)
+               putchar('\n');
        /* No newline here, the line is closed by next value or group end */
        va_end(args);
 }

Thanks,
Sidong

Re: [RFC] btrfs-progs: format-output: remove newline in fmt_end text mode

[David Sterba]

On Sat, Feb 20, 2021 at 04:42:38PM +0000, Sidong Yang wrote:
> On Fri, Feb 19, 2021 at 10:56:11PM +0100, David Sterba wrote:
> > On Tue, Feb 16, 2021 at 04:28:40PM +0000, Sidong Yang wrote:
> > > Remove a code that inserting new line in fmt_end() for text mode.
> > > Old code made a failure in fstest btrfs/006.
> > > 
> > > Signed-off-by: Sidong Yang <realwakka@gmail.com>
> > > ---
> > > Hi, I've just read mail that Filipe written that some failure about fstest.
> > > I'm worried about this patch makes other problem. So make it RFC. Thanks.
> > 
> > I found the discussion under the device stats patch adding json, the
> > added line was known and "hopefully not causing problems", but the
> > fstests seem to notice.
> > 
> > I think we can fix that by removing the fmt_end newline but we also need
> > to update how the fmt_print is done for the text output. Ie. for json
> > there are some strict rules for line continuations  (",") but for the
> > textual output, each line ended by "\n" right away, without delaying
> > that to the next fmt_* call should work.
> 
> You mean that if this patch applied and the code prints device stats for
> text format manually replaced to fmt_print(), there is no last new line
> for text output? fmt_print() prints new line before print some value now.
> I think that it should prints new line at the end of each fmt_print().
> like below
> 
> diff --git a/common/format-output.c b/common/format-output.c
> index f5b12548..9a9f5bf7 100644
> --- a/common/format-output.c
> +++ b/common/format-output.c
> @@ -242,7 +239,6 @@ void fmt_print(struct format_ctx *fctx, const char* key, ...)
>                 const bool print_colon = row->out_text[0];
>                 int len;
>  
> -               putchar('\n');
>                 fmt_indent1(fctx->indent);
>                 len = strlen(row->out_text);
>  
> @@ -312,6 +308,8 @@ void fmt_print(struct format_ctx *fctx, const char* key, ...)
>         }
>  
>         fmt_end_value(fctx, row);
> +       if (bconf.output_format == CMD_FORMAT_TEXT)
> +               putchar('\n');

Yeah effectively that, but inside fmt_end_value and removing it from
fmt_end. It's fixed in devel now with some comments updated as the plain
text and json are different.