Currently, except for tasks that have no parents, when
a process' children are collapsed the '+' indicator is
shown in the first position within that COMMAND field.
This commit simply provides for indenting the '+' char
so it displays next to that program name/command line.
Signed-off-by: Jim Warner <james.warner@comcast.net>
In that commit referenced below, a few edge cases were
addressed regarding vertical positioning involving any
'hidden' tasks. But, 2 additional edge cases remained.
In a running top, if the user employed 'other filters'
(o/O) or 'user filters' (u/U) proper vertical position
was not ensured. And, while this could be easily fixed
by striking the home/end or up/down arrow keys, it was
very poor etiquette to shift this burden to the users.
So, this patch plugs that gap, automating the process.
Reference(s):
commit c6e68e2fed
Signed-off-by: Jim Warner <james.warner@comcast.net>
Our newlib branch has already dropped support for such
old kernels. However, the master branch still supports
them. So this patch will correct a broken #define that
is used to influence the top Summary Area information.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Using Ctrl-V for the collapse children key now appears
as a mistake. First, it's too close to that Ctrl-C key
which would prematurely terminate top. Second, a lower
case 'v' was unused and perfectly compliments an upper
case 'V' which is used to toggle 'forest view' itself.
Reference(s):
https://gitlab.com/procps-ng/procps/issues/99
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit just addresses these miscellaneous issues:
. always use 'p' for pointers to that proc_t structure
. always match order of local #undef to parent #define
. forest_create use of array index made more efficient
Signed-off-by: Jim Warner <james.warner@comcast.net>
Now, when a parent's children have been collapsed, the
cpu used by those unseen tasks will disappear no more.
Instead such tics will be added to the parent's total.
[ if one wished a return to the 'land of lost tics', ]
[ the '#define TREE_VCPUOFF' directive is available. ]
------------------------------------------------------
Note: With collapsible parents now displaying children
cpu usage, it will eventually be noticed the cpu stats
for the summary area and task areas often vary widely.
It's worth a reminder that for top's summary area each
individual cpu and the cpu summary is limited to 100%,
regardless of how many tics a linux kernel may export.
An individual task is limited to 100% times the number
of threads. But, in no case will cpu usage ever exceed
100% times total number of processors. Such limits are
further reduced under 'Solaris' mode ('I' toggle off).
In this mode, a task cpu usage will never exceed 100%.
These limits will now also apply to collapsed parents.
In addition to those influences, results are subjected
to kernel timer sampling anomalies and the distortions
inherent in a small sample size, made worse by smaller
delay intervals. Often there is just 1 or 2 tics for a
few tasks at smaller intervals such as: 1/10th second.
Anyway, should questions on this subject arise, a good
starting point, beyond the reminders above, is the 1st
link listed below. Those other links were derivatives.
Reference(s):
. from the kernel documentation
https://www.kernel.org/doc/Documentation/cpu-load.txt
. as mentioned in the above kernel documentation
https://lkml.org/lkml/2007/2/12/6
. from above, with many more links on the subject
https://www.boblycat.org/~malc/apc/
Signed-off-by: Jim Warner <james.warner@comcast.net>
top: parent total cpu includes collapsed children, pgm
So that the impact (minimal) of the next commit can be
isolated, this commit just involves a little renaming,
reformat plus a refactor of some proc_t pointer logic.
[ renaming, relocation and changes to 'user_matched' ]
[ wasn't strictly necessary, but now mirrors newlib. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch just addresses some edge cases with respect
to 'unseen' tasks. Given the ability to preserve other
filters in the rcfile, it's entirely possible the very
first task(s) may not be visible at top startup. Also,
when switching between windows ('a'/'w') we should try
to always position its row #1 on some visible process.
Lastly, a window might have *NO* visible tasks at all.
Therefore, protect 'window_hlp' from an infinite loop.
Signed-off-by: Jim Warner <james.warner@comcast.net>
To my knowledge, nobody has ever complained about some
anomalies when scrolling vertically if tasks should be
hidden from view. This can happen with the user filter
('u/U') or other filter ('o/O') features. And although
some tasks are not shown, they still impact scrolling.
This is most apparent when that scroll coordinates msg
is on ('C') & up/down arrow keys used (vs. pgup/pgdn).
Now that we can collapse/expand forked children, there
is a potential for yet more of those hidden processes.
So this commit normalizes vertical scrolling providing
an expected behavior. In other words, the up/down keys
skip the unseen tasks to reposition on a visible task.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch is simply preparation for upcoming vertical
scrolling enhancements. With those changes, it will be
impossible to predict what the beginning task position
should be at the time the message is currently issued.
This patch will allow such a message to be shown after
the individual windows' tasks have all been displayed.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The issue cited below really dealt with preserving the
'Other filter' criteria in the rcfile. But as an aside
the htop 'F6' feature (collapsed children) was raised.
I took that as an implied challenge and decided to try
implementing a similar feature in top. So, this commit
will now provide a brand new forest view toggle ('^V')
which will be used to collapse/expand forked children.
[ this patch will also lead to additional patches in ]
[ support of more rational vertical scrolling, since ]
[ many more tasks might now be hidden in some window ]
Reference(s):
. where this secondary issue was raised
https://gitlab.com/procps-ng/procps/issues/99
Signed-off-by: Jim Warner <james.warner@comcast.net>
In anticipation of a new collapsible child feature, we
will have to make some forest view variables available
to that 'keys_task()' function. This commit just moves
the forest view logic ahead of tertiary input support.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Well, after the rearranging and refactoring, all those
active 'other filter' entries for each window will now
be preserved in the user's configuration file via 'W'.
For raising the issue below, thanks to Marco Ippolito.
Reference(s):
https://gitlab.com/procps-ng/procps/issues/99
Signed-off-by: Jim Warner <james.warner@comcast.net>
If we are to support preserving 'other filter' entries
in the rcfile, then the current logic setting up those
osel entries for a WIN_t must be shareable for startup
and when interacting with a user. So, this commit just
repositions this current code in a shareable function.
[ along the way, we give the prior guy a proper name ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
When we get around to saving that 'Other Filter' stuff
in the rcfile, we'll need access to the Fieldstab plus
the justify_pad() function. So this commit repositions
two 'osel' functions in anticipation of adding 1 more.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The 'config_file()' function was getting a little long
in the tooth, so this commit simply renames/rearranges
some stuff anticipating 'other filters' in the rcfile.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit moves some overhead to the Batch mode path
where it's needed. And given the new 'else if' test we
can delete some now redundant logic in the other path.
Reference(s):
. original qualys patch
0117-top-Prevent-out-of-bounds-writes-in-PUFF.patch
commit 059ae8b512
Signed-off-by: Jim Warner <james.warner@comcast.net>
While it's only documented (so far) in commit text and
an occasional email I've tried to maintain some coding
standards primarily for reference/navigation purposes.
They also served, I felt, as useful mental challenges.
Someday I will get around to formerly documenting them
but in the meantime here are the ones for this commit:
. functions are grouped into logical (i hope) sections
. functions & sections are ordered to avoid prototypes
. function names are alphabetical within every section
. all functions & sections must be referenced in top.h
This patch just attempts to honor the above standards,
while also covering this new behavior in the man page.
[ please note that the net result of these 2 patches ]
[ is simply to avoid pathname truncations should our ]
[ limit of 1024 be exceeded. they do not have a role ]
[ in solving the 'local privilege escalation' issue. ]
[ and we can never prevent a user from setting their ]
[ HOME var to a directory writable by some attacker! ]
[ the only real protection for that CVE-2018-1122 is ]
[ those soon to be enhanced rcfile integrity checks, ]
[ achieved through several of the following patches. ]
Reference(s):
. original qualys patch
0097-top-Do-not-default-to-the-cwd-in-configs_read.patch
commit b45c4803dd
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch prevents three problems:
1/ Because snprintf() returns "the number of characters (excluding the
terminating null byte) which would have been written to the final string
if enough space had been available", _eol may point past the end of _str
and write out-of-bounds (in Batch mode).
2/ _eol is never checked against _str, so "while (*(--_eol) == ' ');"
may point _eol below _str and write out-of-bounds (in Batch mode).
3/ Sanity-check Pseudo_row to protect the strcpy().
After wrestling with extra wide characters, supporting
languages like zh_CN, sometimes default/minimum column
widths might force a truncation of translated headers.
So, this commit explores one way that such truncations
could be avoided. It is designed so as to have minimal
impact on existing code, ultimately affecting just one
function. But it's off by default via its own #define.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Back when top was refactored to support UTF-8 encoding
it was acknowledged that languages like zh_CN were not
supported. That was because a single 'character' might
require more than a single 'column' when it's printed.
Well I've now figured out how to accommodate languages
like that. My adaptation is represented in this patch.
[ and just in case someone wishes to avoid the extra ]
[ runtime costs, a #define OFF_XTRAWIDE is included. ]
Along the way, I've cleaned up some miscellaneous code
supporting the 'Inspect' feature so that the rightmost
screen column was always used rather than being blank.
[ interestingly, my xterm & urxvt terminal emulators ]
[ are able to split extra wide characters then print ]
[ 1/2 of such graphics in the last column. the gnome ]
[ terminal emulator does not duplicate such behavior ]
[ but prints 1 extra character in same width window. ]
Reference(s):
. Sep, 2017 - original utf8 support
commit 7ef38420a4
Signed-off-by: Jim Warner <james.warner@comcast.net>
Those references below offer more detail regarding the
default startup changes beginning with version 3.3.10.
It is important to remember that all such changes were
supposed to impact only new users or users who had not
saved the personal config file (via that 'W' command).
However, I introduced a bug wherein the rcfile was not
fully honored. This gave the changes a bad reputation.
That bug was corrected in release 3.3.11 but the issue
of default startup options keeps resurfacing. And it's
clear there's no consensus on what should be included.
Our --disable-modern-top configure option is of little
help since it remains an all-or-nothing approach. What
we need is an answer offering unlimited customization.
So, this commit will provide distribution packagers or
system administrators with a much more flexible way to
set their own preferred startup default configuration.
A new rcfile is being introduced: '/etc/topdefaultrc',
whose format/content is the same as a personal rcfile.
Thus once a 'proper' enterprise configuration has been
established and saved via 'W', it can be copied to the
/etc/ directory. Thereafter, startup in the absence of
a saved rcfile will use that configuration as default.
Now if a distribution packager or system administrator
wishes to expose their users to some of top's advanced
capabilities they can do so gradually. Perhaps setting
up graph mode for summary area task and memory display
while retaining the %CPU sort could be tried. Or maybe
showing colors, but better customized for a particular
terminal emulator. Such possibilities are now endless.
[ in exploiting this new capability, i hope that the ]
[ other windows (alt display mode) aren't overlooked ]
Reference(s):
. Sep, 2014 - Not fully honoring rcfile bug discussed
https://www.freelists.org/post/procps/top-saved-rcfile-bug
. Oct, 2014 - Attempt to defend new startup defaults
https://bugzilla.redhat.com/show_bug.cgi?id=1153049
. Jul, 2015 - Forest vs. %CPU views discussion
https://gitlab.com/procps-ng/procps/issues/6
. Oct, 2017 - Question the use of --disable-modern-top
https://bugzilla.redhat.com/show_bug.cgi?id=1499410
. Oct, 2017 - Forest vs. %CPU views discussion again
https://www.freelists.org/post/procps/Forest-mode-by-default-in-top-seems-a-bit-strange
. Dec, 2017 - Rehash of 3.3.10 startup defaults change
https://gitlab.com/procps-ng/procps/issues/78
Signed-off-by: Jim Warner <james.warner@comcast.net>
Way back in November of 2011, the library was equipped
with an overridable error message handler function. It
was done expressly for a program like top which alters
the tty. But that support was withdrawn shortly after.
This was all done in the lead up to v3.3.2. That's the
release where NLS support was added and it represented
a hectic time. In hindsight, the changes went too far.
So this commit, in a minimal fashion, restores ability
to address a potential fatal library error. After all,
any properly behaving library would never unilaterally
subject a caller to a stderr message and then an exit.
[ when exposing 1 variable in libprocps.sym, 2 other ]
[ existing symbols were repositioned alphabetically. ]
Reference(s):
. generalized library memory provisions
commit 7126cc4491
. top exploit library memory provisions
commit 88087ec5a5
. library xalloc type functions made private
commit 2865ded64e
. restored prior top memory logic
commit 05f5deb97c
Signed-off-by: Jim Warner <james.warner@comcast.net>
With the help of our Swedish translator, hopefully the
final buglet has now been vanquished in the multi-byte
translation support. This one was a real nasty bugger.
Although it didn't occur with every terminal emulator,
occasionally random text lines were being chopped off.
As it turns out, those terminals were blameless. There
were two separate places in top's show_special routine
where potential multi-byte sequences were inadequately
addressed. Solution: exploit existing utf-8 functions.
[ it also became apparent that the translation hints ]
[ in the top_nls module were deficient. so a special ]
[ caution was added regarding the final line of txt. ]
Reference(s):
https://gitlab.com/procps-ng/procps/issues/68
Signed-off-by: Jim Warner <james.warner@comcast.net>
Since all the necessary utf-8 plumbing is now in place
this commit will extend multi-byte support to user and
group names. Now top will be on a par with the ps guy.
[ plus, it's also my way of showing appreciation for ]
[ all those investments silently made by translators ]
Reference(s):
https://gitlab.com/procps-ng/procps/issues/68
Signed-off-by: Jim Warner <james.warner@comcast.net>
The previous commit implemented multi-byte support for
the basic top user interaction and display provisions.
This commit completes multi-byte support by addressing
that 'Inspect Other Output' feature (the 'Y' command).
Few people probably exploit this very powerful feature
which allows the perusing of any file or piped output.
And even if nobody uses 'Y', someone will stumble over
it on the help screen and try it out. Assuming top was
not built with INSP_OFFDEMO defined, they'll end up on
the screen our translators have faithfully translated.
Without this patch, such a screen would display with a
bunch of 'unprintable' characters which will then show
in the standard (less-like) way as: '^A', '<C3>', etc.
In other words, those poor screens will be a big mess!
[ this program can even display an executable binary ]
[ while at that same time supporting Find/Find Next. ]
[ imagine, a file with no guarantee of real strings! ]
[ just try a Find using less with such binary files. ]
With this commit, the translated 'Y' demo screens will
now be properly shown, providing no invalid multi-byte
characters have been detected. Should that be the case
then they'll be displayed in that less-like way above.
And, if users go on to fully exploit this 'Y' command,
there is a good chance that a file or pipe might yield
output in a utf-8 multi-byte form. Should that be true
such output will thus be handled appropriately by top.
[ in many respects, this change was more challenging ]
[ than the basic support within the previous commit. ]
[ story of my life: least used = most effort needed. ]
Many thanks to our procps-ng translators which enabled
a proper test of these changed 'Y' command provisions:
. Vietnamese: Trần Ngọc Quân
. Polish: Jakub Bogusz
. German: Mario Blättermann
. French: Frédéric Marchal, Stéphane Aulery
[ and my sincerest apologies too, for my negligence! ]
Reference(s):
https://gitlab.com/procps-ng/procps/issues/68
Signed-off-by: Jim Warner <james.warner@comcast.net>
When this project first began implementing translation
support nearly 6 years ago, we overcame many 'gettext'
obstacles and limitations. And, of course, there were
not any actual translations at the time so our testing
was quite limited plus, in many cases, only simulated.
None of that, however, can justify or excuse the total
lack of attention to top's approach to NLS, especially
since some actual translations have existed for years.
When the issue referenced below was raised, I suffered
immediate feelings of anxiety, doubt and pending doom.
This was mostly because top strives to avoid line wrap
at all costs and that did not bode well for multi-byte
translated strings, using several bytes per character.
I was also concerned over possible performance impact,
assuming it was even possible to properly handle utf8.
But, after wrestling with the problem for several days
those initial feelings have now been replaced by guilt
over any trouble I initially caused those translators.
One can only imagine how frustrating it must have been
after the translation effort to then see top display a
misaligned column header and fields management page or
truncated screens like those of help or color mapping.
------------------------------------------------------
Ok, with that off my chest let's review these changes,
now that top properly handles UTF8 multi-byte strings.
. Performance - virtually all of this newly added cost
for multi-byte support is incurred during interactions
with the user. So, performance is not really an issue.
The one occasion when performance is impacted is found
during 'summary_show()' processing, due to an addition
of one new call to 'utf8_delta()' in 'show_special()'.
. Extra Wide Characters - I have not yet and may never
figure out a way to support languages like zh_CN where
the characters can be wider than most other languages.
. Translated User Name - at some future point we could
implement translation of user names. But as the author
of the issue acknowledged such names are non-standard.
Thus task display still incurs no new multi-byte costs
beyond those already incurred in that escape.c module.
For raising the issue I extend my sincerest thanks to:
Göran Uddeborg
Reference(s):
https://gitlab.com/procps-ng/procps/issues/68
Signed-off-by: Jim Warner <james.warner@comcast.net>
The top program already incorporated a modest delay at
startup so that some minimal process cpu history could
be established. However, Summary Area system level cpu
statistic history reflected usage since boot. As such,
unchanging % values would be shown with every restart.
This commit just adopts the same approach used in task
%CPU history for the Summary Area statistics. In other
words, it introduces a 'priming read' at startup as is
found in the newlib implementation for the <stat> API.
Reference(s):
https://gitlab.com/procps-ng/procps/merge_requests/42
Signed-off-by: Jim Warner <james.warner@comcast.net>
All of top's display was designed to fit into an 80x24
terminal. This includes the help screens plus both the
Summary and Task Areas, assuming no saved config file.
With release 3.3.10, the startup defaults were changed
assuming ./configure --disable-modern-top wasn't used.
This was done in the hope of introducing some users to
unknown capabilities such as colors, forest view, etc.
The purpose of this commit is to coax a few more users
into possibly exploring another capability: scrolling.
We do so by tweaking the default startup display so as
to show full command lines. Now, when things no longer
fit in 80x24, horizontal scrolling might be exploited.
[ of course, this can be reversed with the -c switch ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
In their 3.2.7 version of top, Redhat introduced an -M
switch to automatically scale Summary Area memory data
to avoid truncation (and the resulting '+' indicator).
The procps-ng top does not employ suffixes with memory
data nor does it allow for different scaling with each
separate value. Rather, scaling appears at line start.
If built without ./configure --disable-modern-top, the
Summary Area memory will be scaled at GiB which should
lessen chance of truncation. Otherwise KiB was used to
reflect such memory, increasing the truncation chance.
And while 'W' can be used to preserve some appropriate
scaling value, there are arguments against such rcfile
approaches as cited in the issue and bug report below.
So this commit will bump the Summary Area memory scale
factor from KiB to MiB when using --disable-modern-top
as a concession to that Redhat bug report noted below.
And it also introduces a new command line switch which
can force any desired scaling regardless of the rcfile
or which ./configure option might have been specified.
[ for top's help text we'll show 'E' as if it were a ]
[ switch without arguments in order to keep the help ]
[ text displayable without wrap in an 80x24 terminal ]
[ the man page, however, will show all k-e arguments ]
Reference(s):
https://gitlab.com/procps-ng/procps/issues/53https://bugzilla.redhat.com/show_bug.cgi?id=1034466
Signed-off-by: Jim Warner <james.warner@comcast.net>
After much reflection I've come to the conclusion that
displaying 3 decimal places (usually) when memory data
had been scaled is no longer optimal with today's ever
increasing amounts. And given that not all task memory
fields are the same widths, inconsistencies can easily
arise as illustrated and discussed in the issue below.
Instead of unilaterally reducing the number of decimal
places, this commit will sneak in such a change via an
existing configure option that was very likely unused.
The former 'disable-wide-memory' option has now become
'enable-wide-memory', which can be used if the current
behavior (3 decimal places) is preferred. Without that
option, whenever memory is scaled beyond KiB, just one
decimal place will be shown in Summary and Task areas.
And Task area field width will no longer be changed by
this revised configure option. Instead, all such field
widths will now be fixed at the former maximum values.
Reference(s):
https://gitlab.com/procps-ng/procps/issues/50
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit provides for raising the total displayable
fields from its current 70 to 86. It also bumps the id
in an rcfile representing the version from 'i' to 'j'.
The increase in number of fields will make sharing the
rcfile with an older top, once it's saved, impossible.
These changes are being done via a #define rather than
hard coded so any such sharing will still be possible.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch adapts the ps program to a newly add proc_t
field and provides for new support in that top program
along with his man document (ps was already ok there).
Signed-off-by: Jim Warner <james.warner@comcast.net>
Now that the conditional OOMEM_ENABLE has been removed
and all users exposed to those 'out of memory' fields,
it's about time we added them to the top man document.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit just tries to parallel the implementations
in the newlib branch. The config file Rc.zero_suppress
will be extended to include both out-of-memory fields.
And while we're at it, we'll also extend zero suppress
to that NI (nice value) field, which already should've
had it. Plus we trade those namespaces custom suppress
logic for our now slightly enhanced make_num function.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Since support already exists in the newlib branch this
represents an equivalent master branch implementation,
and this commit message is shared with 2 more patches.
Beginning with linux-4.5, the following new fields are
being added under that /proc/<pid>/status pseudo file:
. RssAnon - size of resident anonymous memory
. RssFile - size of resident file mappings
. RssShmem - size of resident shared memory
p.s. Locked resident memory support was also added but
isn't directly related to the kernel 4.5 enhancements.
p.p.s. Archlinux, Debian-stretch and Fedora-23 already
are currently using a 4.5 linux kernel (as of 6/2/16).
Signed-off-by: Jim Warner <james.warner@comcast.net>
A patch containing the following miscellaneous tweaks:
. remove a function that handled former library errors
[ that function should have gone bye-bye with 3.3.11 ]
[ when those 'wchan' provisions were much simplified ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jeeze, to correct spelling on one single word (incure)
you had to go and align the entire comments paragraph?
[ well, at least there's one other minor code change ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit just tweaks top in the following respects:
. for alphabetic integrity, change 'INSP_hdr...' names
. eliminate the -Wsometimes-uninitialized warning that
was found under OSX Yosemite (llvm 6.0/clang-600.0.56)
. update program 'comments' reflecting copyright dates
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent commit eliminated the potential for a storage
violation with forest view mode. It occurred when some
program (erroneously?) created a lengthy forking loop.
However, the associated commit message was misleading.
The message implied that an unexpected order following
a sort on start_time was the cause of storage overruns
and a 'char' used to track nesting level only distorts
the display when it goes negative. Actually, the truth
is really just the opposite. Any start_time sort quirk
causes no harm while that 'char' can yield corruption.
Should some child end up sorted ahead of its parent by
way of an extremely unlikely shared start_time the end
result is such a child will be displayed unnested just
like init or kthreadd along with all its own children.
However, if nesting levels exceeded 255 (and became 0)
a massive array overrun could be triggered when such a
task and *all* its children were added to an array for
the second time. Exactly how much storage was violated
depended on the number of children that zeroed process
had spawned (hinted at via either SIGSEGV or SIGABRT).
The earlier commit limited nested levels to 100 so the
root cause of the storage violation was already fixed.
The potential for distorted nesting levels due to sort
on start_time would seem to remain. But it's extremely
unlikely that 2 tasks would share the same start_time.
Even so, a new #define has been introduced which makes
top impervious to the order of tasks such that a qsort
is no longer necessary (providing an init/systemd task
exists & was harvested as the first task by readproc).
It can be utilized if distorted nesting ever becomes a
real issue. But since there is a 5-10% performance hit
with that, we'll continue using start_time as default.
References(s):
commit ce70017eb1
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit will eliminate a very nasty bug associated
with top's forest view mode. It addresses a potential
SIGSEGV/SIGABRT that was only encountered when another
program (erroneously?) creates a lengthy forking loop.
If the growing list of nested children is sufficiently
fast such that proc_t start_time is duplicated between
children then the sort upon which top relies might not
produce the expected order. That, in turn, could cause
the forest_adds function to initially miss some child.
But that missed child would be caught by forest_create
and eventually would cause our array boundary overrun.
Such overrun occurs when some child of that originally
*missed* child is found and a duplicate add attempted.
In correcting this bug we'll also use this opportunity
to prohibit a borrowed proc_t padding byte (char) from
going negative. If the nesting level exceeded 127, the
effect was an "unnesting" with the snprintf width then
viewed as flag+width also yielding left justification.
Henceforth, we'll limit nesting to 100 with subsequent
children shown as " + ", not the usual " `- " prefix.
References(s):
https://bugzilla.redhat.com/show_bug.cgi?id=1153642http://www.freelists.org/post/procps/Bug-in-the-forrest-view,6
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will cure a potential aberration associated
with a terminal's size (SIGWINCH) and top's new graphs
modes. The symptoms were a dangling tilde (~) plus the
potential loss of a graph's right-most visual content.
The condition was only apparent when a %Cpu approached
100% usage. Also the apparent loss of content affected
the 'block' graph only. With 'bar' graphs, that affect
became the loss of proper right-most bar graph colors.
The cause was determined to be a combination of: 1) an
unnecessary snprintf precision specification; and 2) a
rounding quirk for any graphs which displayed distinct
types of information (as for user/syst, used/unavail).
These could then combine to produce an extra bar/block
which, in turn, resulted in the truncation of a pseudo
termcap attribute used by the show_special() function.
What was originally interpreted as an intractable race
condition turns out to be just a self inflicted wound.
Reference(s):
http://www.freelists.org/post/procps/top-Possible-bug-in-the-graphs,1
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will trade a former pessimistic calculation
of free physical memory for a more optimistic one that
uses the newly added kb_main_available library export.
But in case one might wish to return to the old former
method, there's a new #define that was made available.
[ the new calculation will affect graphing mode only ]
Reference(s):
http://www.freelists.org/post/procps/systemd-support-to-library,9
Signed-off-by: Jim Warner <james.warner@comcast.net>
For over a decade top has used a startup configuration
mimicking the original redhat top. This decision dates
back to when the forked Sourceforge version was trying
to win over users in battles with that ancient kludge.
Will anybody deny that those defaults are coyote ugly?
Well, it is time that top presented a more modern look
at startup, providing that no saved rcfile exists. But
just in case some distro prefers that old, comfortable
look, there's the '--disable-modern-top' build option.
[ Pssst. With the widened memory fields it turns out ]
[ the 'Mem' default window had become almost useless ]
[ on an 80x24 terminal since %CPU & COMMAND were out ]
[ of view. So some other defaults were tweaked a bit ]
[ whether or not --disable-modern-top was specified. ]
Reference(s)
http://www.freelists.org/post/procps/tops-graph-mode-saga-continues,3
Signed-off-by: Jim Warner <james.warner@comcast.net>
