Add a new DynamicMeter class for runtime Meter extension

This commit is based on exploratory work by Sohaib Mohamed.
The end goal is two-fold - to support addition of Meters we
build via configuration files for both the PCP platform and
for scripts ( https://github.com/htop-dev/htop/issues/526 )

Here, we focus on generic code and the PCP support.  A new
class DynamicMeter is introduced - it uses the special case
'param' field handling that previously was used only by the
CPUMeter, such that every runtime-configured Meter is given
a unique identifier.  Unlike with the CPUMeter this is used
internally only.  When reading/writing to htoprc instead of
CPU(N) - where N is an integer param (CPU number) - we use
the string name for each meter.  For example, if we have a
configuration for a DynamicMeter for some Redis metrics, we
might read and write "Dynamic(redis)".  This identifier is
subsequently matched (back) up to the configuration file so
we're able to re-create arbitrary user configurations.

The PCP platform configuration file format is fairly simple.
We expand configs from several directories, including the
users homedir alongside htoprc (below htop/meters/) and also
/etc/pcp/htop/meters.  The format will be described via a
new pcp-htop(5) man page, but its basically ini-style and
each Meter has one or more metric expressions associated, as
well as specifications for labels, color and so on via a dot
separated notation for individual metrics within the Meter.

A few initial sample configuration files are provided below
./pcp/meters that give the general idea.  The PCP "derived"
metric specification - see pmRegisterDerived(3) - is used
as the syntax for specifying metrics in PCP DynamicMeters.
This commit is contained in:
Nathan Scott
2021-06-23 17:44:56 +10:00
parent 865b85eb2d
commit f0ed0fdafb
48 changed files with 1044 additions and 68 deletions

View File

@ -50,6 +50,14 @@ static void CPUMeter_init(Meter* this) {
}
}
// Custom uiName runtime logic to include the param (processor)
static void CPUMeter_getUiName(const Meter* this, char* buffer, size_t length) {
if (this->param > 0)
xSnprintf(buffer, sizeof(length), "%s %u", Meter_uiName(this), this->param);
else
xSnprintf(buffer, sizeof(length), "%s", Meter_uiName(this));
}
static void CPUMeter_updateValues(Meter* this) {
unsigned int cpu = this->param;
if (cpu > this->pl->cpuCount) {
@ -326,6 +334,7 @@ const MeterClass CPUMeter_class = {
.display = CPUMeter_display
},
.updateValues = CPUMeter_updateValues,
.getUiName = CPUMeter_getUiName,
.defaultMode = BAR_METERMODE,
.maxItems = CPU_METER_ITEMCOUNT,
.total = 100.0,