From: Sascha Hauer <s.hauer@pengutronix.de>
To: Marco Felsch <m.felsch@pengutronix.de>
Cc: Barebox List <barebox@lists.infradead.org>
Subject: Re: [PATCH 2/5] dmesg: error out on unknown loglevels
Date: Tue, 13 Jun 2023 08:49:22 +0200 [thread overview]
Message-ID: <20230613064922.GE18491@pengutronix.de> (raw)
In-Reply-To: <20230613063439.qrzzbp55m3333lp2@pengutronix.de>
On Tue, Jun 13, 2023 at 08:34:39AM +0200, Marco Felsch wrote:
> Hi Sascha,
>
> On 23-06-12, Sascha Hauer wrote:
> > The user deserves an error when an unknown loglevel is given, so
> > print an error instead of silently ignoring unknown loglevels.
> >
> > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> > ---
> > commands/dmesg.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/commands/dmesg.c b/commands/dmesg.c
> > index 339910bb76..2a36710b98 100644
> > --- a/commands/dmesg.c
> > +++ b/commands/dmesg.c
> > @@ -32,6 +32,8 @@ static int str_to_loglevel(const char *str)
> > if (!strcmp(str, "emerg"))
> > return MSG_EMERG;
> >
> > + printf("dmesg: unknown loglevel %s\n", str);
> > +
> > return -EINVAL;
> > }
> >
> > @@ -51,6 +53,8 @@ static unsigned dmesg_get_levels(const char *__args)
> > level = str_to_loglevel(str);
> > if (level >= 0)
> > flags |= BIT(level);
> > + else
> > + return 0;
>
> This is more explicit but wouldn't be required since we initialized
> 'flags = 0'.
It is required as flags might be != 0 already and we want to return 0
in error case. Nevertheless this needs fixing as this return looses
memory allocated with xstrdup above.
>
> > }
> >
> > free(args);
> > @@ -81,7 +85,7 @@ static int do_dmesg(int argc, char *argv[])
> > case 'l':
> > levels = dmesg_get_levels(optarg);
> > if (!levels)
> > - return COMMAND_ERROR_USAGE;
> > + return COMMAND_ERROR;
>
> Out of curiosity what's the difference between COMMAND_ERROR and
> COMMAND_ERROR_USAGE?
When a command returns with COMMAND_ERROR_USAGE then the usage
for the command is printed. COMMAND_ERROR just returns an error
without printing the commands usage.
When a command prints a meaningful error message then I often
find it confusing when the usage is printed, because the error
is often buried in the long help text.
Sascha
---------------------------8<------------------------------
>From adadd6c0fcfd6b11076e0110497dd7ecdb44f99c Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Mon, 12 Jun 2023 14:12:11 +0200
Subject: [PATCH] dmesg: error out on unknown loglevels
The user deserves an error when an unknown loglevel is given, so
print an error instead of silently ignoring unknown loglevels.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
commands/dmesg.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/commands/dmesg.c b/commands/dmesg.c
index 339910bb76..0d46353fb5 100644
--- a/commands/dmesg.c
+++ b/commands/dmesg.c
@@ -32,6 +32,8 @@ static int str_to_loglevel(const char *str)
if (!strcmp(str, "emerg"))
return MSG_EMERG;
+ printf("dmesg: unknown loglevel %s\n", str);
+
return -EINVAL;
}
@@ -49,8 +51,12 @@ static unsigned dmesg_get_levels(const char *__args)
break;
level = str_to_loglevel(str);
- if (level >= 0)
- flags |= BIT(level);
+ if (level < 0) {
+ flags = 0;
+ break;
+ }
+
+ flags |= BIT(level);
}
free(args);
@@ -81,7 +87,7 @@ static int do_dmesg(int argc, char *argv[])
case 'l':
levels = dmesg_get_levels(optarg);
if (!levels)
- return COMMAND_ERROR_USAGE;
+ return COMMAND_ERROR;
break;
case 'r':
flags |= BAREBOX_LOG_PRINT_RAW | BAREBOX_LOG_PRINT_TIME;
--
2.39.2
--
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next prev parent reply other threads:[~2023-06-13 6:50 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-12 12:32 [PATCH 0/5] implement dmesg -n Sascha Hauer
2023-06-12 12:32 ` [PATCH 1/5] dmesg: factor out str_to_loglevel() Sascha Hauer
2023-06-13 6:41 ` Marco Felsch
2023-06-12 12:32 ` [PATCH 2/5] dmesg: error out on unknown loglevels Sascha Hauer
2023-06-13 6:34 ` Marco Felsch
2023-06-13 6:49 ` Sascha Hauer [this message]
2023-06-13 6:57 ` Marco Felsch
2023-06-12 12:32 ` [PATCH 3/5] dmesg: allow loglevels specified as numbers Sascha Hauer
2023-06-13 6:41 ` Marco Felsch
2023-06-12 12:32 ` [PATCH 4/5] dmesg: implement dmesg -n Sascha Hauer
2023-06-13 6:45 ` Marco Felsch
2023-06-13 6:54 ` Sascha Hauer
2023-06-12 12:32 ` [PATCH 5/5] dmesg: udpate help Sascha Hauer
2023-06-13 6:40 ` Marco Felsch
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