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 introduces an initial platform for extracting metrics
using the PCP performance metrics API - PMAPI(3). It can
be used via the --enable-pcp=yes configure option.
So far I've added support for live localhost metrics only,
and only using pre-defined metrics already found in htop.
If available, all sampling is performed by pmcd(1) - else,
we fallback to htop doing the metric sampling itself (all
below the PMAPI). When pmcd is used, it may be configured
to run children with elevated privileges, so htop does not
need to be setuid (authentication with pmcd is available).
Additionally, the PMAPI allows us to support archives (for
historical analysis and for automated regression tests in
htop). We'll need platform-specific command line argument
additions, which isn't yet feasible in htop (not difficult
to add though).
The goal of this first version is minimal impact in terms
of modifying the htop codebase, to introduce key ideas in
PCP (metric namespace, metadata, APIs and so on) and give
us something to discuss, experiment with and build on.
Refactor the sample time code to make one call to gettimeofday
(aka the realtime clock in clock_gettime, when available) and
one to the monotonic clock. Stores each in more appropriately
named ProcessList fields for ready access when needed. Every
platform gets the opportunity to provide their own clock code,
and the existing Mac OS X specific code is moved below darwin
instead of in Compat.
A couple of leftover time(2) calls are converted to use these
ProcessList fields as well, instead of yet again sampling the
system clock.
Related to https://github.com/htop-dev/htop/pull/574
One review request relating to the PCP platform is to have
a clearly separate binary from the regular htop so that we
have no confusion as to what is being requested to run, to
aid debugging, and a bunch of other good reasons.
This commit renames htop.c to CommandLine.c and provides a
minimal htop main function for 'native' platforms to use.
The PCP version of this will setup libpcp.so and then call
the same CommandLine_run function as regular htop.
Related to https://github.com/htop-dev/htop/pull/536
Code that is shared across some (but not all) platforms
is moved into a 'generic' home. Makefile.am cleanups to
match plus some minor alphabetic reordering/formatting.
As discussed in https://github.com/htop-dev/htop/pull/553
Several of our newer meters have merged coding concerns in terms
of extracting values and displaying those values. This commit
rectifies that for the SysArch and Hostname meters, allowing use
of this code with alternative front/back ends. The SysArch code
is also refined to detect whether the platform has an os-release
file at all and/or the sys/utsname.h header via configure.ac.
As SYSCONFDIR is a compile time string literal, use compile time string
concatenation instead of a runtime one.
Also drop related TODO, cause we indeed using the correct way of getting
$sysconfdir from autoconf
At start, SysArchMeter calls the uname function to obtain the kernel
version and architecture. If available, the distro version is obtained
by calling lsb_release. The obtained values are stored in static
variables and used when updating the meter.
- require autoconf version 2.69
was released in 2012 and one still can configure and build on older
systems (just not generate the configure script)
- use modern C99 compiler check
- drop obsolete checks: AC_C_CONST, AC_FUNC_CLOSEDIR_VOID, AC_FUNC_STAT
- drop AC_HEADER_STDBOOL in favor of C99 compatibility
Use only one enum instead of a global and a platform specific one.
Drop Platform_numberOfFields global variable.
Set known size of Process_fields array
taskstats is only checked on runtime if the column RCHAR, WCHAR, SYSCR,
SYSCW, RBYTES, WBYTES, CNCLWB, IO_READ_RATE, IO_WRITE_RATE or IO_RATE is
selected.
taskstats is currently enabled by default.
Drop the taskstats configuration switch, to reduce the maintenance cost.
cgroup is only checked on runtime if the column CGROUP is selected.
cgroup is currently disabled by default, but most distributions do
enable it.
Drop the cgroup configuration switch, to reduce the maintenance cost.
Add a date meter and sort header and source files in Makefile
Change the lists of header and source files sorted alphabetical and one
file per line. This way diffs become better readable and merges easier.
For a process with a very long command, especially with many long
command line arguments, inspecting the command and its arguments could
become inconvenient.
Meanwhile htop supports the concept of "screen", or window, which is
extended here to create a dedicated "CommandScreen", making it possible
to display the command of the selected process in a separate window
meanwhile being wrapped into multiple lines.
Another benefit of using a command screen is, the user can navigate
through the wrapped lines of the command and perform actions like
searching and filtering.
- enable warnings in autogen script
- drop unused m4/ directory usage
- drop AC_TYPE_SIGNAL:
C99 guarantees the signal return type to be void
- drop AC_CHECK_FILE of procdir:
most of the time compilation is done on a different system than htop is run
and there is a runtime check in place
- improve linux_affinity corss compile logic:
use fourth argument instead of pre-test
The MIN, MAX, CLAMP, MINIMUM, and MAXIMUM macros appear
throughout the codebase with many re-definitions. Make
a single copy of each in a common header file, and use
the BSD variants of MINIMUM/MAXIMUM due to conflicts in
the system <sys/param.h> headers.
Nathan Scott