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
pgrp and session might be -1
linux/LinuxProcessList.c:312:20: runtime error: implicit conversion from type 'unsigned long' of value 18446744073709551615 (64-bit, unsigned) to type 'unsigned int' changed the value to 4294967295 (32-bit, unsigned)
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior linux/LinuxProcessList.c:312:20 in
linux/LinuxProcessList.c:314:23: runtime error: implicit conversion from type 'unsigned long' of value 18446744073709551615 (64-bit, unsigned) to type 'unsigned int' changed the value to 4294967295 (32-bit, unsigned)
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior linux/LinuxProcessList.c:314:23 in
- avoid UBSAN conversions
- print N/A on no data (i.e. as unprivileged user)
- fix rate calculation to show bytes (instead of a thousandth)
- print bytes as human number (i.e. 8MB) instead of 8388608
- stabilize sorting by adjusting NAN values to very tiny negative number
It is only used on Linux to optimize memory handling in case the command
changes to a smaller-or-equal string.
This "optimization" however causes more code bloat and maintenance cost
on string handling issues than it gains.
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
This acheives two things:
- Allows for simple tie-breaking if values compare equal (needed to make sorting the tree-view stable)
- Allows for platform-dependent overriding of the sort-order for specific fields
Also fixes a small oversight on DragonFlyBSD when default-sorting.
* This removes duplicated code that adjusts the sort direction from every
OS-specific folder.
* Most fields in a regular htop screen are OS-independent, so trying
Process_compare first and only falling back to the OS-specific
compareByKey function if it's an OS-specific field makes sense.
* This will allow us to override the sortKey in a global way without having
to edit each OS-specific file.
- Add Settings forward declaration in Process.h
- Add assert.h include in XUitls.c
- Add conditional stdbool.h include in Object.h
- Drop unneeded stddef.h include in Richstring.c
- Drop unneeded unistd.h include in Process.h
- Drop unneeded string.h include in linux/Platform.c
- Use String_eq to avoid string.h include in Action.c
- Improve script to run custom iwyu version
man:sysconf(3) states:
The values obtained from these functions are system configuration constants.
They do not change during the lifetime of a process.
When building on a 32-bit system, the compiler warned that the
following line uses a constant whose value is the overflow result
of a compile-time computation:
Process.c (line 109): } else if (number < 10000 * ONE_M) {
Namely, this constant expression:
10000 * ONE_M
was intended to produce the following value:
10485760000
However, the result overflowed to produce:
1895825408
The reason for this overflow is as follows:
o The macros are expanded:
10000 * (ONE_K * ONE_K)
10000 * (1024L * 1024L)
o The untyped constant expression "10000" is typed:
10000U * (1024L * 1024L)
o The parenthesized expression is evaluated:
10000U * (1048576L)
o The left operand ("10000U") is converted:
10000L * (1048576L)
Unbound by integer sizes, that last multiplication
would produce the following value:
10485760000
However, on a 32-bit machine, where a long is 32 bits
(really 31 bits when talking about positive numbers),
the maximum value that can be computed is 2**31-1:
2147483647
Consequently, the computation overflows.
o The compiler produces a long int value that is the
the result of overflow (10485760000 % 2**31):
1895825408L
Actually, I think this overflow is implementation-defined,
so it's not even a portable description of what happens.
The solution is to use a long long int (or, even better,
an unsigned long long int) type for the constant expression;
the C standard mandates a sufficiently large maximum value
for such types.
Hence, the following change is made to the bad line:
- } else if (number < 10000 * ONE_M) {
+ } else if (number < 10000ULL * ONE_M) {
However, the whole line is now patently silly, because the
variable "number" is typed "unsigned long", and so it will
always be less than the constant expression (the compiler
will warn about this, too).
Hence, "number" must be typed "unsigned long long"; however,
this necessitates changing all of the string formats from
something like "%lu" to something like "%llu".
Et voila! This commit is born.
Then, for the sake of completeness, the declared types of the
constant-expression macros are updated:
o ONE_K is made unsigned (a "UL" instead of "L")
o ONE_T is computed by introducing "1ULL *"
o Similar changes are made for ONE_DECIMAL_{K,T}
Also, a non-portable overflow-conversion to a signed value
has been replaced with a portable comparison:
- if ((long long) number == -1LL) {
+ if (number == ULLONG_MAX) {
It might be worth reviewing the rest of the code for other
cases where overflows are not handled correctly; even at
runtime, it's often necessary to check for overflow unless
such behavior is expected (especially for signed integer
values, for which overflow has implementation-defined
behavior).
- `CRT_fatalError()` is declared twice in CRT.h
- `Process_pidFormat`, `Process_writeField()` and `Process_compare` are
declared twice in Process.h
- `btime` is defined in LinuxProcess.c and also declared in
LinuxProcess.h, so drop in LinuxProcessList.h
PR htop-dev/htop#70 got rid of the infrastructure for generating header
files, but it left behind some code duplication.
Some of cases are things that belong in the header file and don't need
to be repeated in the C file. Other cases are things that belong in the
C file and don't need to be in the header file.
In this commit I tried to fix all of these that I could find. When given
a choice I preferred keeping things out of the header file, unless they
were being used by someone else.
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.
Nathan Scott