Currently htop does not support offline CPUs and hot-swapping, e.g. via
echo 0 > /sys/devices/system/cpu/cpu2/online
Split the current single cpuCount variable into activeCPUs and
existingCPUs.
Supersedes: #650
Related: #580
`RichString_appendnAscii()` avoids a `strlen(3)` call over
` RichString_appendAscii()`.
Use the former where the length is available from a previous checked
`snprintf(3)` call.
Keep `RichString_appendAscii()` when passing a string literal and
rely on compilers to optimize the `strlen(3)` call away.
Always show the number of kernel and userland threads, even when they
are disabled to not be shown in the process list.
The data is already available and might improve understanding the system
utilization.
Use a shadow color in case the kind of thread is hidden, else the normal
meter one.
RichString_writeFrom takes a top spot during performance analysis due to the
calls to mbstowcs() and iswprint().
Most of the time we know in advance that we are only going to print regular
ASCII characters.
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.
Reasoning:
- implementation was unsound -- broke down when I added a fairly
basic macro definition expanding to a struct initializer in a *.c
file.
- made it way too easy (e.g. via otherwise totally innocuous git
commands) to end up with timestamps such that it always ran
MakeHeader.py but never used its output, leading to overbuild noise
when running what should be a null 'make'.
- but mostly: it's just an awkward way of dealing with C code.
operation is not possible to be conducted in an atomic fashion, task
scheduling effects can lead to a count greater than the number of actual
processors; this is more easily noticed on machines with several CPUs
and under heavy workload.
This patch simply adds an upper bound on cpuCount to guarantee
consistent reports of the number of running tasks at any given time.
In all the cases where sprintf was being used within htop, snprintf
could have been used. This patch replaces all uses of sprintf with
snprintf which makes sure that if a buffer is too small to hold the
resulting string, the string is simply cut short instead of causing
a buffer overflow which leads to undefined behaviour.
`sizeof(variable)` was used in these cases, as opposed to `sizeof
variable` which is my personal preference because `sizeof(variable)`
was already used in one way or another in other parts of the code.
Rationale (copied from htop issue #471):
The function name "setValues" is misleading. For most OOP (object-
oriented programming) contexts, setXXX functions mean they will change
some member variables of an object into something specified in
function arguments. But in the *Meter_setValues() case, the new values
are not from the arguments, but from a hard-coded source. The caller
is not supposed to change the values[] to anything it likes, but
rather to "update" the values from the source. Hence, updateValues is
a better name for this family of functions.
Two changes in this commit:
- All meters now explicitly specify "maxItems" property, even for just
1 item. (Exception is "container" CPU meter classes, which use
CUSTOM_METERMODE.)
- "maxItems" being 0 is now allowed. This will let bar meters and graph
meters render an empty meter.
Fix subtree hiding
Fix reading of CPU values in hidden threads
Fix hiding of zombie processes as kernel threads
Remove "debug proc" code
Code cleanup in processElements
