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>
Might as well use the newly exposed sysinfo.h variable
'page_bytes' rather than our own. Plus, in the process
we can avoid incurring yet one more function call hit.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Gosh, just because most of us might run with some swap
file allocated, not every system might. I only wish my
testing methodology was as sophisticated as Jaromir's.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements,7
Signed-off-by: Jim Warner <james.warner@comcast.net>
When startup argument parsing was recently enhanced to
account for LC_NUMERIC settings, some user input logic
dealing with numbers fails to exploit that capability.
This patch extends such enhancements to a running top.
Reference(s):
commit f7b84f45c7http://www.freelists.org/post/procps/topwatch-floating-point-input,2
Signed-off-by: Jim Warner <james.warner@comcast.net>
When those new cpu/memory graphs modes were introduced
they had global impact. In other words, the modes that
were chosen for a 'current' window affect Summary Area
appearance for every other window as well, even though
each window sets unique View_STATES/View_MEMORY flags.
I do not know how widespread the use of top's separate
window provisions is, but I do know that documentation
promises every window (field group) provides "a unique
separately configurable summary area". And even though
that promise does not include memory scaling (separate
'E' command) the graph modes are integral to 't' & 'm'
and those were already observed on a per window basis.
So this patch just takes the cpu and memory graph mode
values out of global scope in the configuration file &
gives each window its own unique pair of graph values.
Reference(s):
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
Boy I hate locale stuff. For code I thought was pretty
robust, Jaromir sure proved that it wasn't. Anyway, me
thinks this commit closes some gaps and will cause top
to behave appropriately under various locale settings.
It does *not* permit top to respond to the ',' and '.'
floating point separator without regard to the locale.
It does, however, enforce proper LC_NUMERIC responses.
Let's look on this commit as an interim solution until
Jaromir can create that proposed 'fp_decode' function.
Who knows, he might even borrow some of our mkfloat().
[ An aside: the coreutils sleep and timeout programs ]
[ claim to permit floating point arguments. However, ]
[ neither one will accept the comma separator should ]
[ the locale be a country that in fact uses a comma. ]
[ In other words, with this commit we are way ahead! ]
Reference(s):
http://www.freelists.org/post/procps/topwatch-floating-point-inputhttp://www.freelists.org/post/procps/topwatch-floating-point-input,1
Signed-off-by: Jim Warner <james.warner@comcast.net>
While there was no harm done setting a handler for the
above two signals, they are in fact uncatchable. Thus,
whenever we ran with valgrind we're politely reminded.
Signed-off-by: Jim Warner <james.warner@comcast.net>
When the beginning of the Mem/Swap graphs was variable
scaling them to the current terminal's width was a bit
of a costly nightmare. So the graph size was fixed and
subject to truncation. However now that the start of a
graph can be easily predicted, I've revisited scaling.
As it turns out, any cost is minimal & mostly incurred
at an opportune time, at SIGWINCH or user interaction.
Plus, most of the apparent arithmetic is actually just
a means of documenting and will disappear thru compile
time constants in the ultimate generated machine code.
Note: those graphs will now behave just like any other
Summary Area element - they will scale from full sized
down to a terminal width of 80 columns, at which point
those displayed graphs are then subject to truncation.
Signed-off-by: Jim Warner <james.warner@comcast.net>
While the 'b' toggle remains window based (vs. global)
it should no longer require that the window be visible
and either the 'x' or 'y' toggles to be on. Previously
those requirements were intended to remind a user that
there must be something for this command to highlight.
With the introduction of graph modes (specifically the
the bar graph) the 'bold/reverse' toggle has important
implications beyond highlighting some columns or rows.
The %Cpu(s) graph and Mem portion of the memory graphs
are designed to offer a visual clue as to the separate
elements comprising them. But that separation could be
lost under some X color schemes or when top is running
without color (in monochrome mode) and the block graph
is selected. But, if the graph is then changed to bars
any separation always becomes visible whenever the 'b'
toggle is turned off. Portions then show in 'reverse'.
So from now on we'll check nothing, we'll just toggle.
[ Besides, with all the code thrown at restricting a ]
[ 'b' toggle use, it might have all been for naught. ]
[ That toggle could still be set/unset using the 'Z' ]
[ command and the color mapping screen. Geez Louise! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
My original graph modes implementation made no attempt
to align the Cpu & Mem/Swap graphs. I thought, rather,
that such alignment could be best achieved by the user
using top's 'E' memory scaling command toggle. In that
way Mem/Swap prefixes could be reduced by 3 positions,
bringing the beginning '[' into line with the %Cpu(s).
If that proved to be too cumbersome a #define could be
enabled making the Mem/Swap prefix static while adding
a few padding bytes to the %Cpu line(s) for alignment.
It was those waisted bytes that were the most concern.
What I had not counted on was the fact that the memory
lines themselves might become misaligned & that became
likely with more physical memory present. That too can
be cured with the 'E' command but as scaling is raised
we soon reach a meaningless total such as '0.003' even
though the displayed % remains valid (and unchanging).
So this commit implements unconditionally what used to
be conditional. But, instead of waisting padding bytes
we'll put that space to good use with a new 'total %'.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements,1
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
My first blush graphs modes implementation went just a
tad overboard on identifier lengths. As a result, some
program lines were getting quite long. So, this commit
will simply shorten some excessively long identifiers.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch makes 't' (View_STATES) & 'm' (View_MEMORY)
commands into 4-way toggles. The two new modes provide
for two different graphs of the cpu and/or memory use.
These new capabilities are similar to those offered by
the 'htop' program. However they're aesthetically more
pleasing (to me) plus the scalings are more authentic.
Poor ol' top has long been troubled by the comparisons
offered up by the 'htop' program. Many of those things
were only true of the original redhat top while others
are no longer true of this current top program. So let
me use this commit msg to begin to correct the record.
Corrected comparisons between 'htop' & 'top' programs:
------------------------------------------------------
+ htop does not start faster, actually reverse is true
+ top offers scrolling vertically and horizontally too
. (and top offers better <Home> and <End> key support)
+ unassigned keystrokes don't subject top to any delay
. (but htop suffers that annoying ncurses <Esc> delay)
+ in top one need not type the PID to kill the process
+ in top one need not type the PID to renice a process
Some things the 'htop' program was not bragging about:
------------------------------------------------------
+ top can outperform the htop program by a wide margin
+ htop + SIGWINCH = corrupted display + restart likely
+ htop cannot preserve its screen data at suspend/exit
+ the htop column management scheme is very cumbersome
+ htop allows columns to be duplicated again and again
+ htop displays only full command lines, not pgm names
. (and that 'Command' column must always be displayed)
. (and it must always remain as the last column shown)
+ htop does not provide for any sort of command recall
+ htop's search feature does not highlight any matches
+ there is no 'find next' outside of htop search modes
+ htop does not allow Header or Process memory scaling
+ htop provides no flexibility on column justification
+ htop does not provide the means to change col widths
+ htop provides less control over colors configuration
+ htop always overwrites the rcfile with any UI change
Someday, maybe we'll provide a better comparison as an
addendum for (or replacement of) that README.top file.
Signed-off-by: Jim Warner <james.warner@comcast.net>
In anticipation of upcoming memory graphing provisions
the abbreviations 'Mem' and 'Swap' are being made into
individual translatable strings in order to be reused.
Additionally, the Mem 'used' amount will now no longer
included the 'buffers' and 'cached' values. Thus, each
Mem category becomes unique. This is the approach used
by tools such as 'htop' or the gnome 'System Monitor'.
Lastly, with that change to the 'used' category it has
been repositioned after 'free' on the Mem & Swap lines
making a comparison between 'total' and 'free' easier.
Signed-off-by: Jim Warner <james.warner@comcast.net>
For some time now, top has refrained from updating the
current number of cpus and memory totals with each and
every refresh cycle. Rather, to lessen overhead costs,
such values are updated periodically (5 min & 3 secs).
The delay in updating the cpu count was only important
with the addition of a cpu, since any loss is detected
immediately. And the large interval was chosen because
of the costs once associated with a glibc sysconf call
and an unlikely scenario of physically adding the cpu.
But the ease with which cpus can be taken offline then
placed back online under linux suggests that 5 minutes
may be too high. So, without addressing the likelihood
of that act, top is now more responsive in these ways:
1) that 5 minute interval has been reduced to 1 minute
2) any key, not just Enter/Space, refreshes cpus & mem
Note: we leave the man document as is, suggesting that
only the Enter/Space keys force an update for hotplug.
Signed-off-by: Jim Warner <james.warner@comcast.net>
. prevent any input recall overrun if window downsized
. adjust translation notes for true column hdr maximum
Signed-off-by: Jim Warner <james.warner@comcast.net>
In release 3.3.6, some commands were equipped with the
concept of a 'default pid'. The initial implementation
meant that the intuitive <Esc> key would not always be
treated as one would expect under any well behaved UI.
This patch ensures the expected <Esc> key behavior of:
terminating user input while still making possible the
necessary distinction between 'no input' & 'defaults'.
Reference(s):
http://www.freelists.org/post/procps/top-Escape-doesnt-abort-kill-command
Signed-off-by: Jim Warner <james.warner@comcast.net>
The granularity of /proc/uptime is fixed at hundredths
of a second. And, since we can cycle faster than that,
we are exposed to 'nan' when calculating elapsed time.
This commit will protect us from that outcome when the
delay interval has been set to an extremely low value.
Signed-off-by: Jim Warner <james.warner@comcast.net>
If a system's time is adjusted backwards, then elapsed
time could appear as negative. This yielded a negative
%CPU value. Alternately if zeros were suppressed ('0')
the result was a blank %CPU column. In both cases that
distortion would last for one display cycle or until a
user forced a display refresh via some keyboard input.
The original recommendation was trading gettimeofday()
for clock_gettime() using CLOCK_MONOTONIC. But on some
systems that might not be possible, forcing the use of
CLOCK_REALTIME instead. Not only would that complicate
the build system, but it may leave us with minus %CPU.
Another approach was to ensure that elapsed time could
never be negative. Of course, this produced distortion
of %CPU values but it would be proportionally correct.
This wasn't dissimilar to a distortion already present
should the time be adjusted forward or backward within
any 'remaining' top delay intervals. These aberrations
would be avoided with clock_gettime & CLOCK_MONOTONIC,
but that is a less than ideal solution as noted above.
This final solution, which originated down under, will
simply rely on the /proc/uptime seconds, which will be
immune to *any* tampering with the system clock. Thus,
we now have a fix for the distortion we didn't know we
suffered plus a negative %CPU that began this odyssey.
Thanks to:
sk.alvin.x@gmail.com, for the original effort
jcapik@redhat.com, for a heads up on CLOCK_MONOTONIC
csmall-procps@enc.com.au, for the best suggestion of all
Reference(s):
. original post/patch
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday
. heads up on CLOCK_MONOTONIC
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday,2
. the final solution
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday,11
Signed-off-by: Jim Warner <james.warner@comcast.net>
Minor fixes that the translator (Yuri) has found in some of the
strings. You only know how many typos and thinkos you have when
someone is trying to translate it.
Signed-off-by: Craig Small <csmall@enc.com.au>
Since its inception top has always used enumerators to
identify displayable fields. They've taken the form of
P_PID, etc. As it turns out, something has changed for
libc6-dev versions beyond 2.17-93 wherein 'P_PID' will
now be exposed via stdlib.h. I have not pinpointed the
exact cause but it may depend on header include order.
This patch just trades top's long standing 'P_' prefix
convention for that of 'EU_' (short for enumerator). I
cannot find *any* header under /usr/include/ currently
utilizing this particular three character combination.
And as a further safeguard top will henceforth include
'system' specific headers after the standard includes.
Reference(s):
http://www.freelists.org/post/procps/top-wont-compile-anymore
Signed-off-by: Jim Warner <james.warner@comcast.net>
When top originally responded to the potential libnuma
stderr write, the library was consistently called with
each refresh cycle. That, in turn, guaranteed that any
warning message would be seen at program end by virtue
of: 1) having been issued before the 2nd refresh cycle
and; 2) benefiting from inherited /dev/null buffering.
A later efficiency refactor meant the numa library may
not always be called with every refresh cycle. Rather,
it was only called if top was in one of two numa views
(the '2' or '3' toggles). That, in turn, resulted in a
loss of any warning message at program end unless numa
mode had been preserved in the rcfile. In other words,
if top was started normally then a single cycle stderr
redirect would have long passed by the time the '2' or
'3' toggle was activated. The warning message actually
was spewed but quickly lost to the full screen refresh
which follows all keyboard interactions with the user.
This commit simply moves the restoration of our stderr
redirect to program end (instead of that first display
refresh). Now, any libnuma stderr warning message will
appear as the concluding output line upon quitting top
without regard to when any numa mode view was invoked.
And since this technique might be useful in some other
context (as an example of how to 'buffer' stderr) it's
been generalized with its own #define. But to maximize
its usefulness, the original redirect should be issued
much earlier in pgm startup than top has chosen to do.
Reference(s):
. original libnuma stderr response (msg seen)
commit 35dc6dcc49
. numa refractoring for efficiency (msg lost)
commit f12c0d5c6e
Signed-off-by: Jim Warner <james.warner@comcast.net>
Apparently there are occasions when NUMA nodes may not
always be contiguous. Under such conditions nodes that
were not used would still occupy precious Summary Area
space showing 100% idle, under the '2' command toggle.
With this commit top will no longer display numa nodes
that have no associated cpu when the '2' toggle is on.
But just in case we wish to return to former behavior,
a new #define called OFF_NUMASKIP has been introduced.
And as an aside, a recent refactor mentioned below set
the stage for this patch to be 'self-tuning'. In other
words, if an inactive/non-displayed node should become
active (if even possible), then top will begin showing
such a node automatically with the next screen update.
Unfortunately, all inactive nodes now 'suppressed' are
still accessible via the '3' command. Those nodes will
just be displayed as empty (no associated cpus shown).
This is not really a top problem but more of a libnuma
and/or user deficiency. The library lacks the means to
validate a node id and the user then input a node that
was not even shown under a '2' toggle Summary display.
( too bad libnuma does not offer an 'is_node_active' )
( type function so top could warn a user when such a )
( discontinuous node was requested using his '3' cmd )
( sure, top could achieve this objective himself but )
( that would require making yet another array global )
( which i'm just not in the mood to do - besides, we )
( have already made enough concessions to libnuma.so )
Lastly, an existing #define (PRETEND_NUMA) was changed
to 'disable' node #1 so as to simulate a discontinuous
node. This allows testing of the '2' and '3' commands.
Reference(s):
http://www.spinics.net/lists/util-linux-ng/msg08671.html
. set stage for self tuning
commit f12c0d5c6e
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent change involving a one cycle stderr redirect,
to handle a libnuma potential transgression, failed to
follow normal global variable naming conventions. This
patch will capitalize the 1st letter of 'Stderr_save'.
Reference(s):
commit 35dc6dcc49
Signed-off-by: Jim Warner <james.warner@comcast.net>
Excluding those special X_XON/X_XOF enums, which might
not even be present, restore strict collating order of
all the case labels in the task_show switch statement.
Also, adjust a few sort callbacks for the same reason.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The recent addition of namespaces, combined with those
potential suse out-of-memory fields, means that we are
close to the maximum number of fields poor ol' top can
display. Imagine, the really old top was limited to 26
fields (28 with the suse hack) and this top had neared
the version 'g' rcfile limits which were a healthy 55.
This patch adds another 15 fields to the maximum while
making it even easier to increase in the future. Also,
top still silently accommodates older config files all
the way back to the original pre-ng version top-3.2.8!
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch is inspired by the 'minimize numa overhead'
patch. It trades the use of subscripts for pointers to
avoid gcc repeated subscript offset calculation bloat.
Now, throughout the cpus_refresh function, a subscript
will be resolved just once & this will (dramatically?)
reduce the path-length taken for each and every frame!
For example, a non-optimized compilation could produce
400+ fewer machine instructions through pointer usage.
[ ok, optimized compiles only save 18+ instructions! ]
Lastly, any residual 'symmetry only' crap is now gone!
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent libnuma potential corruption problem solution
has caused me to reevaluate some associated numa logic
for efficiency. Here is a summary of the problems that
exist with current libnuma/user possible interactions:
. Whenever the numa library was present extra overhead
would always be incurred in maintaining the node stats
even when the '2' or '3' commands were not being used.
. As part of such overhead a separate loop was used to
reinitialize each cpu/node structure with each display
cycle so that prior accumulated totals were preserved.
Again, it didn't matter if numa data was really shown.
This commit attempts to refocus on the 'critical path'
costs in a running top by optimizing for the occasions
when numa node data is not being displayed. Under such
conditions, no extra overhead will be incurred whether
or not a distribution has the libnuma library present.
To achieve this goal, some additional overhead will be
incurred, but only when actually displaying numa data.
And all such new costs have been minimized in spite of
the gcc inclination to duplicate subscript resolution.
Reference(s):
commit 24bd950cb2e1722d459461f0f9c0c30a4b9ffdaa
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent libnuma potential corruption problem solution
suggests that libnuma could change in the future so as
to not spew to stderr. This then raises a question how
top could exploit any such library change since we are
currently locked into version #1 of the library by way
of our dlopen("libnuma.so.1", RTLD_LAZY) runtime call.
While not an ultimate solution, this commit will first
try for the most recent version of that library during
top's startup before trying the original libnuma.so.1.
We do this via the unqualified library soname symlink.
For this new dlopen() call to succeed, technically the
numa 'devel' package would usually have been required,
but that's not always true with every distro. And when
the libnuma.so symlink isn't present, it can always be
manually added should a newer & better behaved library
arrive & users tire of the stderr warning at top exit.
Reference(s):
commit 24bd950cb2e1722d459461f0f9c0c30a4b9ffdaa
Signed-off-by: Jim Warner <james.warner@comcast.net>
There is a chance that the libnuma library may corrupt
top's display with some stderr warning messages in the
event something under /sys/devices/system/node/ cannot
be accessed. And, while 2 overridable 'weak' functions
are provided to alter such behavior, we can't use them
since top dynamically links to the library via dlopen.
This commit will redirect stderr to '/dev/null' during
just the first screen display cycle. Thus we can avoid
the corruption which would have remained visible until
the underlining screen row's data had finally changed.
Lastly, this patch should allow such a library warning
to actually appear when one finally exits our program.
[ i think the libnuma folks should consider changing ]
[ the error/warning interfaces to accommodate dlopen ]
[ rather than forcing something like the ugly kludge ]
[ we have employed or libnuma dependency on everyone ]
Reference(s):
https://bugzilla.redhat.com/show_bug.cgi?id=998678
Signed-off-by: Jim Warner <james.warner@comcast.net>
When Other filtering was introduced the nature of what
constituted a displayed row changed. No longer would a
task_show() call guarantee that another line is shown.
Rather, a non-empty string must have also been tested.
Unfortunately, when any task window was being filtered
for 'idle' mode or a particular 'user', the proc index
was incremented twice due to the perils of copy/paste.
Combining such an index increment with the new test of
task_show results works fine if filtering is inactive.
This was a particularly insidious bug which meant that
an adjacent task would be skipped whenever the current
task met 'idle' and/or 'user' filter criteria, and was
not otherwise excluded due to 'Other' filter criteria.
And, since it was the very next task that was ignored,
the bug was very susceptible to a window's sort order.
This could be illustrated when filtering on some user,
while sorting on PID. Then, toggling Forest View could
make otherwise unseen tasks appear and then disappear.
User workarounds are possible via interactive commands
trading the 'i' and 'u'/'U' provisions for the 'o'/'O'
other filtering capability thus avoiding an extra i++.
But that is certainly less than ideal and doesn't help
the 3.3.7 and 3.3.8 distorted command line provisions.
( this little buggie may end up costing me my pocket )
( protector, my coding badge & maybe even my cubicle )
Reference(s):
http://www.freelists.org/post/procps/Idle-elides-nonidle-processes
. bug originated with 'Other' filtering
commit 5edc6fb317
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch adds the final newline when exiting 'Batch'
mode. Interestingly, it has been missing since release
3.3.5 but undetected until the Redhat bugzilla report.
Reference(s):
https://bugzilla.redhat.com/show_bug.cgi?id=1008674
Signed-off-by: Jim Warner <james.warner@comcast.net>
Normally, the internally tracked 'Screen_cols' can not
exceed the lessor of 512 or actual screen width. There
was one case, however, where that 512 byte upper limit
was no longer properly imposed as it should have been.
When operating in 'Batch' mode the actual screen width
was allowed to be exceeded when the optional -w switch
was also used. But, it should never have exceeded 512.
This patch ensures the upper limit is always observed.
Reference(s):
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=721204
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch addresses the four '-Wunused-result' errors
generated whenever an optimized compile is invoked. It
also made the configs_read() guy a little more robust.
In the process, some logic was rearranged slightly and
some comments were re-indented simply for consistency.
Reference(s):
warning: ignoring return value of 'fgets', declared with attribute warn_unused_result [-Wunused-result]
warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result]
Signed-off-by: Jim Warner <james.warner@comcast.net>
When the final solution for cursor positioning for all
^Z or ^C cases was introduced the revised placement of
message line management introduced with the window mgr
'screen' refactor was retained. Those two commits mean
that a former tgoto was no longer needed when clearing
that msg line or displaying the scroll coordinate msg.
This patch eliminates the tgoto employed by frame_make
while assimilating a now defunct show_scroll function.
Reference(s):
. final cursor positioning for ^Z or ^C
commit 46a1356219
. 'screen' window manager refactor
commit 0fe393ff27
Signed-off-by: Jim Warner <james.warner@comcast.net>
Some more (very obscure) conditions where a suspension
or program end might embed the shell prompt within top
output have been uncovered beyond the 2 already known.
We had already covered some suspend/end contingencies:
1. the users were using the 'fields management' screen
2. the users were prompted for any line oriented input
However, there remained some situations where ^Z or ^C
could still produce a misplaced cursor + shell prompt:
3. the 'g' command while waiting for the window choice
4. the 'W' command if about to overwrite an old rcfile
5. the '=' command when exploiting the Inspect feature
6. the period during which any error message was shown
But, even when all those bases are covered there still
remains a remote possibility that such interrupts will
occur during a top repaint cycle. So rather than throw
yet more code at these self-inflicted problems perhaps
it is better if we just throw in the proverbial towel.
Thus, I'll take the only sane approach and restore the
results expected ever since top's inception and before
scrollback buffers entered the picture. Namely, with a
^Z or ^C the cursor will be placed on the final screen
row. That usually means it will immediately follow the
last output line but it may follow many blank lines if
the user interrupts top when *not* on the main screen.
Reference(s):
. expanded repositioning (for line oriented input)
commit 33104a2bcc
. introduced repositioning (for fields management)
commit 5c974ff44d
. scrollback buffers (the cursor handling changes)
commit dedaf6e1a8
Signed-off-by: Jim Warner <james.warner@comcast.net>
An obscure bug has been discovered where a 'W' with an
old rcfile, warning against overwrite, would display a
cursor that should normally be hidden. This followed a
user's reply. So some logic was rearranged just a bit.
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent patch introduced the ability to recognize the
need to reposition the cursor at suspension or program
end. There remained unmet 1 additional potential need.
This commit extends that ability to embrace line input
so that if a user issues ^Z or ^C while being prompted
the resulting shell output will no longer be embedded.
Reference(s):
http://www.freelists.org/post/procps/top-library-miscellaneous-tweaks,7
commit 5c974ff44d
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit mostly justs renames a few identifiers but
it also will now suppress any end-of-job report if top
wasn't ended via the 'q' key convention (i.e. signal).
Signed-off-by: Jim Warner <james.warner@comcast.net>
The title of this commit is actually quite misleading.
Were it more accurate, it would at least mention a tty
emulator's scrollback buffer, which was the cumulation
of a long pursuit to reduce the SIGWINCH overhead when
a window manager carelessly floods an application with
that signal *while* a user is still resizing a window!
Disabling and enabling that scrollback buffer resulted
in the final top display replaced with original screen
contents, a phenomenon acknowledged at the time but it
also represented a user interface change which has now
produced the first request for return to old behavior.
After the SIGWINCH dust settled, another problem arose
regarding behaviors under the 'screen' window manager.
In response, top was refactored a bit to avoid display
corruption. That was before discovering 'screen' could
duplicate the scrollback buffer behavior top expected.
As it turns out, the 'screen' refactoring had probably
made scrollback buffer manipulation unnecessary. Still
one could argue that a window should not be allowed to
scroll while a constantly updating program was active.
The solution represented in this commit returns former
behavior at program end (retaining top's last screen).
And if we ever wish to disable scrollback buffers, the
associated logic was retained but made conditional. It
is not reflected in configure.ac but might be someday.
Lastly, this commit corrects cursor positioning when a
^C is issued under 'Fields Management' at any terminal
that didn't have a scrollback buffer (i.e. a console).
Reference(s):
https://bugzilla.redhat.com/show_bug.cgi?id=977561http://www.freelists.org/post/procps/top-library-miscellaneous-tweaks,1
. screen program refactor
commit 0fe393ff27
. scrollback buffer disabled
commit dedaf6e1a8
. sigwinch management defines
commit adca737758
commit 4f33b6b8c5
Signed-off-by: Jim Warner <james.warner@comcast.net>
