The safety of the critical function task_show() depends on the sanity of
Screen_cols. Just copy the tests on w_cols to Screen_cols (from the same
function adj_geometry()).
The default action for SIGURG is to ignore the signal, for example.
This is very similar to the patch "ps/display.c: Always exit from
signal_handler()."
Otherwise they may lead to out-of-bounds writes (snprintf() returns the
number of characters which would have been written if enough space had
been available).
Also, make sure buf is null-terminated after COLPLUSCH has been written.
0097-top: Do not default to the cwd in configs_read().
If the HOME environment variable is not set, or not absolute, use the
home directory returned by getpwuid(getuid()), if set and absolute
(instead of the cwd "."); otherwise, set p_home to NULL.
To keep the changes to a minimum, we rely on POSIX, which requires that
fopen() fails with ENOENT if the pathname (Rc_name) is an empty string.
This integrates well into the existing code, and makes write_rcfile()
work without a change.
Also, it makes the code in configs_read() easier to follow: only set and
use p_home if safe, and only set Rc_name if safe (in all the other cases
it is the empty string, and the fopen() calls fail). Plus, check for
snprintf() truncation (and if it happens, reset Rc_name to the empty
string).
Important note: top.1 should probably be updated, since it mentions the
fallback to the current working directory.
0084-proc/readproc.c: Work around a design flaw in readeither().
readeither() caches (in new_p) a pointer to the proc_t of a task-group
leader, but readeither()'s callers can do pretty much anything with the
proc_t structure passed to and/or returned by this function. For
example, they can 1/ free it or 2/ recycle it (by passing it to
readeither() as x).
1/ leads to a use-after-free, and 2/ leads to unexpected behavior when
taskreader()/simple_readtask() is called with new_p equal to x (this is
not a theoretical flaw: 2/ happens in readproctab3() when want_task()
returns false and p is a group leader).
As a workaround, we keep a copy of new_p's first member (tid) in static
storage, and the next times we enter readeither() we check this "canary"
against the tid in new_p: if they differ, we reset new_p to NULL, which
forces the allocation of a new proc_t (the new "leader", or reference).
This always detects 2/ (because free_acquired(x,1) memsets x and hence
new_p); always detects 1/ if freed via free_acquired() and/or freeproc()
(very likely, otherwise memory may be leaked); probably detects 1/ even
if freed directly via free() (because the canary is the first member of
proc_t, likely to be overwritten by free()); but can not detect 1/ if
free() does not write to new_p's chunk at all.
Moreover, accessing new_p->tid to check the canary in case 1/ is itself
a use-after-free, so a better long-term solution should be implemented
at some point (we wanted to avoid intrusive and backward-incompatible
changes in this library function, hence this imperfect workaround).
---------------------------- adapted for newlib branch
. adapted via 'patch' (rejected due to 'xcalloc' ref)
. with loss of both readproctab functions, most no longer true
Signed-off-by: Jim Warner <james.warner@comcast.net>
0082-proc/readproc.c: Fix double-free()s in readtask().
If QUICK_THREADS is not defined (it is not by default, but most
distributions enable it) and task_dir_missing is true (only on very old
kernels), then readtask() forgets to reset some of the struct proc_t t's
members, which later results in double-free()s in free_acquired().
For now, we simply synchronized the list of members to be reset with the
list of members freed in free_acquired().
---------------------------- adapted for newlib branch
. now 'cmd' is also dynamic
. just synchronized with those freed in free_acquired
. QUICK_THREADS is now FALSE_THREADS, serving different purpose
. entire patch will be effectively reverted with upcoming refactor
Signed-off-by: Jim Warner <james.warner@comcast.net>
Check the return value of snprintf(), otherwise dst may point
out-of-bounds when it reaches the end of the dst_buffer (the snprintf()
always returns 1 in that case, even if there is not enough space left),
and vMAX becomes negative and is passed to snprintf() as a size_t.
---------------------------- adapted for newlib branch
. adapted via 'patch (without rejections)
Signed-off-by: Jim Warner <james.warner@comcast.net>
This detects an integer overflow of "strlen + 1", prevents an integer
overflow of "tot + adj + (2 * pSZ)", and avoids calling snprintf with a
string longer than INT_MAX. Truncate rather than fail, since the callers
do not expect a failure of this function.
---------------------------- adapted for newlib branch
. logic is now in pids.c
. former 'vectorize_this_str' is now 'pids_vectorize_this'
Signed-off-by: Jim Warner <james.warner@comcast.net>
2/ Limit sz to INT_MAX, because the return value is an int, not an
unsigned int (and because if INT_MAX is equal to SSIZE_MAX, man 2 read
says "If count is greater than SSIZE_MAX, the result is unspecified.")
3/ Always null-terminate dst (unless sz is 0), because a return value of
0 because of an open() error (for example) is indistinguishable from a
return value of 0 because of an empty file.
4/ Use an unsigned int for i (just like n), not an int.
5/ Check for snprintf() truncation.
---------------------------- adapted for newlib branch
. adapted via 'patch (without rejections)
Signed-off-by: Jim Warner <james.warner@comcast.net>
0074-proc/readproc.c: Fix bugs and overflows in file2strvec().
Note: this is by far the most important and complex patch of the whole
series, please review it carefully; thank you very much!
For this patch, we decided to keep the original function's design and
skeleton, to avoid regressions and behavior changes, while fixing the
various bugs and overflows. And like the "Harden file2str()" patch, this
patch does not fail when about to overflow, but truncates instead: there
is information available about this process, so return it to the caller;
also, we used INT_MAX as a limit, but a lower limit could be used.
The easy changes:
- Replace sprintf() with snprintf() (and check for truncation).
- Replace "if (n == 0 && rbuf == 0)" with "if (n <= 0 && tot <= 0)" and
do break instead of return: it simplifies the code (only one place to
handle errors), and also guarantees that in the while loop either n or
tot is > 0 (or both), even if n is reset to 0 when about to overflow.
- Remove the "if (n < 0)" block in the while loop: it is (and was) dead
code, since we enter the while loop only if n >= 0.
- Rewrite the missing-null-terminator detection: in the original
function, if the size of the file is a multiple of 2047, a null-
terminator is appended even if the file is already null-terminated.
- Replace "if (n <= 0 && !end_of_file)" with "if (n < 0 || tot <= 0)":
originally, it was equivalent to "if (n < 0)", but we added "tot <= 0"
to handle the first break of the while loop, and to guarantee that in
the rest of the function tot is > 0.
- Double-force ("belt and suspenders") the null-termination of rbuf:
this is (and was) essential to the correctness of the function.
- Replace the final "while" loop with a "for" loop that behaves just
like the preceding "for" loop: in the original function, this would
lead to unexpected results (for example, if rbuf is |\0|A|\0|, this
would return the array {"",NULL} but should return {"","A",NULL}; and
if rbuf is |A|\0|B| (should never happen because rbuf should be null-
terminated), this would make room for two pointers in ret, but would
write three pointers to ret).
The hard changes:
- Prevent the integer overflow of tot in the while loop, but unlike
file2str(), file2strvec() cannot let tot grow until it almost reaches
INT_MAX, because it needs more space for the pointers: this is why we
introduced ARG_LEN, which also guarantees that we can add "align" and
a few sizeof(char*)s to tot without overflowing.
- Prevent the integer overflow of "tot + c + align": when INT_MAX is
(almost) reached, we write the maximal safe amount of pointers to ret
(ARG_LEN guarantees that there is always space for *ret = rbuf and the
NULL terminator).
---------------------------- adapted for newlib branch
. there were many formatting differences
. i introduced several myself (especially comments)
. stdlib 'realloc' used, not that home grown xrealloc
. stdlib 'realloc' required extra 'return NULL' statement
Signed-off-by: Jim Warner <james.warner@comcast.net>
1/ Replace sprintf() with snprintf() (and check for truncation).
2/ Prevent an integer overflow of ub->siz. The "tot_read--" is needed to
avoid an off-by-one overflow in "ub->buf[tot_read] = '\0'". It is safe
to decrement tot_read here, because we know that tot_read is equal to
ub->siz (and ub->siz is very large).
We believe that truncation is a better option than failure (implementing
failure instead should be as easy as replacing the "tot_read--" with
"tot_read = 0").
---------------------------- adapted for newlib branch
. no real changes, patch refused due to mem alloc & failure return
Signed-off-by: Jim Warner <james.warner@comcast.net>
1/ Use a "size_t num" instead of an "unsigned num" (also, do not store
the return value of sscanf() into num, it was unused anyway).
2/ Check the return value of strchr() and strrchr().
3/ Never jump over the terminating null byte with "S = tmp + 2".
---------------------------- adapted for newlib branch
. newlib doesn't use that 'unlikely' crap
. the cmd field is now also dynamic (like cmdline)
. thus we must account for potential ENOMEM
Signed-off-by: Jim Warner <james.warner@comcast.net>
2/ Avoid an infinite loop if s contains characters other than comma,
spaces, +, -, and digits.
3/ Handle all possible return values of snprintf().
---------------------------- adapted for newlib branch
. we can't use xrealloc(), so we use realloc() instead
. and must account for a mem failure via a return of 1
Signed-off-by: Jim Warner <james.warner@comcast.net>
1/ Do not read past the terminating null byte when hashing the name.
2/ S[x] is used as an index, but S is "char *S" (signed) and hence may
index the array out-of-bounds. Bit-mask S[x] with 127 (the array has 128
entries).
3/ Use a size_t for j, not an int (strlen() returns a size_t).
Notes:
- These are (mostly) theoretical problems, because the contents of
/proc/PID/status are (mostly) trusted.
- The "name" member of the status_table_struct has 8 bytes, and
"RssShmem" occupies exactly 8 bytes, which means that "name" is not
null-terminated. This is fine right now, because status2proc() uses
memcmp(), not strcmp(), but it is worth mentioning.
---------------------------- adapted for newlib branch
. newlib doesn't use that 'unlikely' crap
. newlib also had a '#ifdef FALSE_THREADS'
Signed-off-by: Jim Warner <james.warner@comcast.net>
This function is unused (SIGNAL_STRING is defined by default, and if it
is not, procps does not compile -- for example, there is no "outbuf" in
help_pr_sig()) but fix it anyway. There are two bugs:
- it accepts non-hexadecimal characters (anything >= 0x30);
- "(c - (c>0x57) ? 0x57 : 0x30)" is always equal to 0x57.
---------------------------- adapted for newlib branch
. newlib doesn't use that 'unlikely' crap
Signed-off-by: Jim Warner <james.warner@comcast.net>
0051-proc/escape.c: Prevent buffer overflows in escape_command().
This solves several problems:
1/ outbuf[1] was written to, but not outbuf[0], which was left
uninitialized (well, SECURE_ESCAPE_ARGS() already fixes this, but do it
explicitly as well); we know it is safe to write one byte to outbuf,
because SECURE_ESCAPE_ARGS() guarantees it.
2/ If bytes was 1, the write to outbuf[1] was an off-by-one overflow.
3/ Do not call escape_str() with a 0 bufsize if bytes == overhead.
4/ Prevent various buffer overflows if bytes <= overhead.
This should never happen, because wcwidth() is called only if iswprint()
returns nonzero. But belt-and-suspenders, and make it visually clear
(very important for the next patch).
0048-proc/escape.c: Make sure all escape*() arguments are safe.
The SECURE_ESCAPE_ARGS() macro solves several potential problems
(although we found no problematic calls to the escape*() functions in
procps's code-base, but had to thoroughly review every call; and this is
library code):
1/ off-by-one overflows if the size of the destination buffer is 0;
2/ buffer overflows if this size (or "maxroom") is negative;
3/ integer overflows (for example, "*maxcells+1");
4/ always null-terminate the destination buffer (unless its size is 0).
---------------------------- adapted for newlib branch
. the escape.c now has just a single exported function
. thus SECURE_ESCAPE_ARGS() is needed in only 2 places
. unlike that original patch, macro is executed 1 time
( not like 'escape_command' calling 'escape_strlist' )
( which might then call 'escape_str' multiple times! )
Signed-off-by: Jim Warner <james.warner@comcast.net>
In the human_readable case; otherwise the strcat() that follows may
append bytes to the previous contents of buf.
Also, slightly enlarge buf, as it was a bit too tight.
Could also replace all sprintf()s with snprintf()s, but all the calls
here output a limited number of characters, so they should be safe.
---------------------------- adapted for newlib branch
. the source file is now proc/uptime.c
. function is now named 'procps_uptime_sprint()'
. new human readable function 'procps_uptime_sprint_short()'
. both were already initialized, so just raised size of 2 buffers
Signed-off-by: Jim Warner <james.warner@comcast.net>
0042-proc/slab.h: Fix off-by-one overflow in sscanf().
In proc/slab.c, functions parse_slabinfo20() and parse_slabinfo11(),
sscanf() might overflow curr->name, because "String input conversions
store a terminating null byte ('\0') to mark the end of the input; the
maximum field width does not include this terminator."
Add one byte to name[] for this terminator.
---------------------------- adapted for newlib branch
. file is now proc/slabinfo.c (not .h)
. manifest constant renamed SLABINFO_NAME_LEN
. older parse_slabinfo11() function no longer present
Signed-off-by: Jim Warner <james.warner@comcast.net>
---------------------------- adapted for newlib branch
. file has been moved to: lib/signals.c
. only 'signal_name_to_number()' was impacted
. function 'print_given_signals()' no longer exists
. thus the bulk of original patch no longer applicable
Signed-off-by: Jim Warner <james.warner@comcast.net>
Do not use "sizeof(converted)" in snprintf(), since "converted" is a
"char *" (luckily, 8 >= sizeof(char *)). Also, remove "sizeof(char)"
which is guaranteed to be 1 by the C standard, and replace 8 with 12,
which is enough to hold any stringified int and does not consume more
memory (in both cases, the glibc malloc()ates a minimum-sized chunk).
---------------------------- adapted for newlib branch
. no longer in library, logic now found in lib/signals.c
. craig already addressed "copy" memleak in commit beloww
Craig Small [Thu, 3 May 2018 11:06:05 +0000 (21:06 +1000)]
library: check not undef SIGLOST
sig.c had this odd logic where on non-Hurd systems it would undefine
SIGLOST. Fine for Hurd or amd64 Linux systems. Bad for a sparc which
has SIGLOST defined *and* is not Hurd.
Jim Warner [Wed, 11 Apr 2018 05:00:00 +0000 (00:00 -0500)]
misc: Add some link examples to sysctl.conf (catch up)
--------------- Original Master Branch Commit Message:
Adds both examples to the sample sysctl.conf configuration file
to enable link protection for both hard and soft links.
Jim Warner [Wed, 11 Apr 2018 05:00:00 +0000 (00:00 -0500)]
docs: Note limitation of pidof find scripts (catch up)
--------------- Original Master Branch Commit Message:
pidof will miss scripts that are run a certain way due to how
they appear in procfs. This is just a note to say it might miss
them.
References:
procps-ng/procps#17
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Wed, 11 Apr 2018 05:00:00 +0000 (00:00 -0500)]
watch: use sysconf() for hostname length __ (catch up)
--------------- Original Master Branch Commit Message:
Hurd doesn't have HOST_NAME_MAX, neither does Solaris.
An early fix just checked for this value and used 64 instead.
This change uses sysconf which is the correct method, possibly until
this compiles on some mis-behaving OS which doesn't have this value.
Jim Warner [Wed, 11 Apr 2018 05:00:00 +0000 (00:00 -0500)]
docs: Reword --exec option in watch.1 _____ (catch up)
--------------- Original Master Branch Commit Message:
The manual page for watch for the exec option was confusing and
backwards. Hopefully this one makes more sense.
References:
procps-ng/procps#75
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Fri, 6 Apr 2018 05:00:00 +0000 (00:00 -0500)]
library: replace the troublesome '__BEGIN_DECLS' macro
When 'newlib' was introduced, in the commit referenced
below, the use of that glibc '__BEGIN_DECLS' macro was
standardized. However, as issue #88 revealed, this may
result in a fatal build error with other environments.
So, this patch just trades that macro for the standard
'#ifdef __cplusplus' conventions (thus avoiding use of
all those '#include <features.h>' directives as well).
This patch simply eliminates that glibc specific macro
from all header files which contain no public callable
functions. After all, if user code can't link to them,
then protection from C++ name mangling is unnecessary.
[ we also remove any related '#include <features.h>' ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Mon, 2 Apr 2018 06:00:00 +0000 (00:00 -0600)]
procio: remove glibc dependency & make a proper header
Duplicate that <libio.h> change made in master branch.
While we're at it, let's remove an unnecessary include
from procio.h and reflect in its single prototype what
those 'const char *' params are really supposed to be.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Sun, 1 Apr 2018 06:00:00 +0000 (00:00 -0600)]
sysctl: relocate the procio code to a more proper home
Now that the procio logic was removed from the library
we must move the header file, lest we break make dist.
In the process, we will relocate that source file too.
[ we'll take a slightly different approach than that ]
[ used under the master branch by exploiting those 2 ]
[ non-library directories 'include' and 'lib', while ]
[ avoiding any sysctl hard coded function prototype. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
By default pgrep/pkill should not kill processes in a namespace it is not
part of. If this is allowed, it allows callers to break namespaces they did
not expect to affect, requiring rewrite of all callers to fix.
So by default, we should work in the current namespace. If --ns 0 is
specified, they we look at all namespaces, and if any other pid is specified
we continue to look in only that namespace.
Jim Warner [Wed, 28 Feb 2018 06:00:00 +0000 (00:00 -0600)]
top: show that truncation indicator ('+') consistently
With a little luck, this should be the final tweak for
our support of extra wide characters. Currently, those
characters don't always display the '+' indicator when
they've been truncated. Now, it should always be seen.
[ plus it's done a tad more efficiently via snprintf ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Masatake YAMATO [Sat, 24 Feb 2018 09:03:11 +0000 (18:03 +0900)]
pidof: allow to change a separator put between pids
I frequency use pidof command with strace system call tracer.
strace can trace MULTIPLE processes specified with "-p $PID"
arguments like:
strace -p 1 -p 1030 -p 3043
Sometimes I want to do as following
strace -p $(pidof httpd)
However, above command line doesn't work because -p option
is needed for specifying a pid. pidof uses a whitespace as
a separator. For passing the output to strace, the separator
should be replaced with ' -p '.
This maybe not a special to my use case.
This commit introduces -S option that allows a user to specify a
separator the one wants.
Craig Small [Thu, 1 Mar 2018 10:25:04 +0000 (21:25 +1100)]
sysctl: Bring procio functions out of library
The procio functions that were in the library have been
moved into sysctl. sysctl is not linked to libprocps in
newlib and none of the other procps binaries would need
to read/write large data to the procfs.
Werner Fink [Thu, 18 Jan 2018 10:26:37 +0000 (11:26 +0100)]
Add flexible buffered I/O based on fopencookie(3)
to be able to read and write large buffers below /proc.
The buffers and file offsets are handled dynamically
on the required buffer size at read, that is lseek(2)
is used to determine this size. Large buffers at
write are split at a delimeter into pieces and also
lseek(2) is used to write each of them.
Jim Warner [Sun, 11 Feb 2018 07:11:11 +0000 (01:11 -0600)]
library: expanded to provide for the UID used at login
This patch represents the newlib implementation of Jan
Rybar's merge request referenced below. It essentially
moves that code out of the ps program and into our new
library where it's available via the <pids> interface.
Jim Warner [Fri, 26 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: avoid potential truncation with 'Inspect' feature
As it turns out, that Ukrainian 'demo' text supporting
the '=' command was 152 bytes long, up from an English
version of 80 bytes. Unfortunately, the buffer used to
format all such strings was insufficient at 128 bytes.
Depending on the width of one's terminal, some strange
result could be experienced when a multi-byte sequence
was truncated. So, this just makes that buffer bigger.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Thu, 25 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: allow translated field headers to determine width
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>
Jim Warner [Tue, 23 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: an efficiency tweak to extra wide character logic
When I recently added extra wide character support for
locales like zh_CN, I didn't worry about some overhead
associated with the new calls to 'mbtowc' & 'wcwidth'.
That's because such overhead was usually incurred with
user interactions, not a normal iterative top display.
There was, however, one area where this overhead would
impact the normal iterative top mode - that's with the
Summary display. So I peeked at the glibc source code.
As it turns out, the costs of executing those 'mbtowc'
and 'wcwidth' functions were not at all insignificant.
So, this patch will avoid them in the vast majority of
instances, while still enabling extra wide characters.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Mon, 22 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: standardize width of the %CPU & %MEM columns at 5
There is (should be) no justification for changing the
width of the percentage columns (%CPU, %MEM) depending
on the BOOST_PERCNT #define. So this patch will ensure
that both columns are fixed at their former maximum 5.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Jim Warner [Sat, 13 Jan 2018 06:00:00 +0000 (00:00 -0600)]
library: account for idle state ('I') threads in total
With the documentation update in the commit referenced
below, we should also account for such threads as they
will already be represented in the task/thread totals.
[ and do it in a way that might avoid future changes ]
Jim Warner [Mon, 8 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: adapt utf8 logic to support extra wide characters
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. ]
Jim Warner [Sun, 7 Jan 2018 06:00:00 +0000 (00:00 -0600)]
top: tweak that recent enhancement to startup defaults
When the new approach for startup defaults was adopted
in the reference below, a file might be left open that
technically should be closed. This situation arises in
the unlikely event the #define RCFILE_NOERR is active.
Without that #define, the program will exit early thus
rendering the open file issue moot. However, even with
that #define there was no real harm with an open file.
It simply meant a 2nd FILE struct would have been used
when, or if, the rcfile was written via a 'W' command.
Anyway, this patch ensures such a file will be closed.
Craig Small [Sat, 13 Jan 2018 05:09:54 +0000 (16:09 +1100)]
free: Update tests and fix for previous patch
The previous two patches updated free, but needed a tweak and the tests
also needed to be updated. I've hand-calculated the results using bc and
both the testsuite and bc results equal what free prints out.
Craig Small [Sat, 13 Jan 2018 00:18:09 +0000 (11:18 +1100)]
docs: Document I idle state in ps and top
Linux 4.2 provided a new process state of I which is used for an idle
kernel thread. This new state means that kernel threads do not
contribute to the loadavg as they are no longer state D or S but I.
While both ps and top displayed this state, it wasn't documented in
either manual page until now.
Craig Small [Sun, 7 Jan 2018 01:25:35 +0000 (12:25 +1100)]
sysctl: Don't crash file fopen fails
The commit referenced below put a setvbuf() before checking what
fopen() returned. If the file could not be opened then the file
handle was NULL at setvbuf() crashed.
setvbuf() is now called after checking what fopen() returns and only
when it was successful.
Jan Rybar [Fri, 29 Dec 2017 04:37:49 +0000 (15:37 +1100)]
docs: Mention in sysctl.8 that a filename is read once
Added note into sysctl.8 manpage about directory precedence.
This information may be important for users who create new config files at several destinations. Especially the information about files to be omitted in directories with lower priority shall be given.
Craig Small [Sat, 23 Dec 2017 07:01:38 +0000 (18:01 +1100)]
library: Move runtime signal count check to compile time
Since the value of number_of_signals is known at compile time, we can
use a compile-time check instead. This also adds SIGLOST for the Hurd,
uses the correct signal counts for the Hurd and FreeBSD, and only gives
a compile-time warning when compiled on an unknown platform that it does
not know whether the number of signals is correct.
Jim Warner [Sun, 17 Dec 2017 06:00:00 +0000 (00:00 -0600)]
top: allow more flexible approach for startup defaults
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>
Jim Warner [Sat, 16 Dec 2017 06:00:00 +0000 (00:00 -0600)]
top: let's exploit the new standardized errno handling
With the library having now normalized errno handling,
perhaps it is time at least one program took advantage
of it. So, instead of printing just a message with the
programs's line number, top will now also provide that
associated errno string text, compliments of strerror.
[ with those newlib functions returning NULL, we can ]
[ use errno directly in strerror. for the ones which ]
[ yield an int, all we need do is invert such return ]
[ values before passing it to the strerror function. ]
Reference(s):
Signed-off-by: Jim Warner <james.warner@comcast.net>