[LEDE-DEV] odhcpd: [PATCH 1/3] enable loglevel setting via envvar ODHCPD_LOG_LEVEL

From: Karl Palsson <karlp@etactica.com>

Currently the loglevel is hardcoded to LOG_WARNING, even though there is
debug log messages.  Allow an env var to control the log threshold.

Signed-off-by: Karl Palsson <karlp@etactica.com>
---
 src/odhcpd.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

On 22/09/2016 19:32, Karl Palsson wrote:
> From: Karl Palsson <karlp@etactica.com>
> 
> Currently the loglevel is hardcoded to LOG_WARNING, even though there is
> debug log messages.  Allow an env var to control the log threshold.
> 
> Signed-off-by: Karl Palsson <karlp@etactica.com>
> ---
>  src/odhcpd.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/src/odhcpd.c b/src/odhcpd.c
> index 74830ac..c51cfa1 100644
> --- a/src/odhcpd.c
> +++ b/src/odhcpd.c
> @@ -58,7 +58,21 @@ static void sighandler(_unused int signal)
>  int main()
>  {
>  	openlog("odhcpd", LOG_PERROR | LOG_PID, LOG_DAEMON);
> -	setlogmask(LOG_UPTO(LOG_WARNING));
> +	char *env_log_level = getenv("ODHCPD_LOG_LEVEL");
> +	int log_level = LOG_WARNING;
> +	if (env_log_level) {
> +		char *end;
> +		errno = 0;
> +		long temp = strtol(env_log_level, &end, 0);
> +		if (end == env_log_level || *end != '\0'
> +			|| ((temp == LONG_MIN || temp == LONG_MAX) && errno == ERANGE)
> +			|| (log_level > LOG_DEBUG) || log_level < LOG_EMERG) {
> +			syslog(LOG_ERR, "ODHCPD_LOG_LEVEL envvar was invalid");
> +		} else {
> +			log_level = temp;
> +		}
> +	}
> +	setlogmask(LOG_UPTO(log_level));
>  	uloop_init();

this is pretty bloaty. i am also not sure if using an env var is the
right way to solve this.

	John

>  
>  	if (getuid() != 0) {
>

John Crispin <john@phrozen.org> wrote:
> 
> 
> On 22/09/2016 19:32, Karl Palsson wrote:
> > From: Karl Palsson <karlp@etactica.com>
> > 
> > Currently the loglevel is hardcoded to LOG_WARNING, even though there is
> > debug log messages.  Allow an env var to control the log threshold.
> > 
> > Signed-off-by: Karl Palsson <karlp@etactica.com>
> > ---
> >  src/odhcpd.c | 16 +++++++++++++++-
> >  1 file changed, 15 insertions(+), 1 deletion(-)
> > 
> > diff --git a/src/odhcpd.c b/src/odhcpd.c
> > index 74830ac..c51cfa1 100644
> > --- a/src/odhcpd.c
> > +++ b/src/odhcpd.c
> > @@ -58,7 +58,21 @@ static void sighandler(_unused int signal)
> >  int main()
> >  {
> >  	openlog("odhcpd", LOG_PERROR | LOG_PID, LOG_DAEMON);
> > -	setlogmask(LOG_UPTO(LOG_WARNING));
> > +	char *env_log_level = getenv("ODHCPD_LOG_LEVEL");
> > +	int log_level = LOG_WARNING;
> > +	if (env_log_level) {
> > +		char *end;
> > +		errno = 0;
> > +		long temp = strtol(env_log_level, &end, 0);
> > +		if (end == env_log_level || *end != '\0'
> > +			|| ((temp == LONG_MIN || temp == LONG_MAX) && errno == ERANGE)
> > +			|| (log_level > LOG_DEBUG) || log_level < LOG_EMERG) {
> > +			syslog(LOG_ERR, "ODHCPD_LOG_LEVEL envvar was invalid");
> > +		} else {
> > +			log_level = temp;
> > +		}
> > +	}
> > +	setlogmask(LOG_UPTO(log_level));
> >  	uloop_init();
> 
> this is pretty bloaty. i am also not sure if using an env var
> is the right way to solve this.

sure, strol sucks. But that's "the" way of checking. I could use
atoi, and just convert nulls to some sort of default maybe. As
for an env var, sure, they suck too, I just copied procd, was
trying to be consistent. I'm open to other suggestions. I don't
_need_ the logging anymore, after adding more for the fixing the
"ignore" problem, and with logging feasible, there's probably
more debug that would be relevant, so this patch could be dropped
entirely if it's too much of a headache.

Cheers,
Karl P

On 27/09/2016 01:33, Karl Palsson wrote:
> 
> John Crispin <john@phrozen.org> wrote:
>>
>>
>> On 22/09/2016 19:32, Karl Palsson wrote:
>>> From: Karl Palsson <karlp@etactica.com>
>>>
>>> Currently the loglevel is hardcoded to LOG_WARNING, even though there is
>>> debug log messages.  Allow an env var to control the log threshold.
>>>
>>> Signed-off-by: Karl Palsson <karlp@etactica.com>
>>> ---
>>>  src/odhcpd.c | 16 +++++++++++++++-
>>>  1 file changed, 15 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/src/odhcpd.c b/src/odhcpd.c
>>> index 74830ac..c51cfa1 100644
>>> --- a/src/odhcpd.c
>>> +++ b/src/odhcpd.c
>>> @@ -58,7 +58,21 @@ static void sighandler(_unused int signal)
>>>  int main()
>>>  {
>>>  	openlog("odhcpd", LOG_PERROR | LOG_PID, LOG_DAEMON);
>>> -	setlogmask(LOG_UPTO(LOG_WARNING));
>>> +	char *env_log_level = getenv("ODHCPD_LOG_LEVEL");
>>> +	int log_level = LOG_WARNING;
>>> +	if (env_log_level) {
>>> +		char *end;
>>> +		errno = 0;
>>> +		long temp = strtol(env_log_level, &end, 0);
>>> +		if (end == env_log_level || *end != '\0'
>>> +			|| ((temp == LONG_MIN || temp == LONG_MAX) && errno == ERANGE)
>>> +			|| (log_level > LOG_DEBUG) || log_level < LOG_EMERG) {
>>> +			syslog(LOG_ERR, "ODHCPD_LOG_LEVEL envvar was invalid");
>>> +		} else {
>>> +			log_level = temp;
>>> +		}
>>> +	}
>>> +	setlogmask(LOG_UPTO(log_level));
>>>  	uloop_init();
>>
>> this is pretty bloaty. i am also not sure if using an env var
>> is the right way to solve this.
> 
> sure, strol sucks. But that's "the" way of checking. I could use
> atoi, and just convert nulls to some sort of default maybe. As
> for an env var, sure, they suck too, I just copied procd, was
> trying to be consistent. I'm open to other suggestions. I don't
> _need_ the logging anymore, after adding more for the fixing the
> "ignore" problem, and with logging feasible, there's probably
> more debug that would be relevant, so this patch could be dropped
> entirely if it's too much of a headache.
> 
> Cheers,
> Karl P

being able to set the debug level is good but not like this. why not use
the normal config code path or a commandline option ?

	John