When having excessively long MANPATH env-vars I end up in a problem with this error:
$> man <any command>
man: manpath list too long
To figure out when the manpath list is too long I created this small script:
#!/bin/bash
export MANPATH=
for i in $(seq 50 10000)
do
export MANPATH=/usr:$MANPATH
man -k gcc > /dev/null
[ $? -ne 0 ] && echo "$i ${#MANPATH}" && exit 0
done
and it seems like it breaks at ${#MANPATH} close to 500.
Also man -d does not give me any information I can use... :(
I have never heard (nor found) a limitation to the number of entries in env-vars (besides the maximum length of the environment variables, from which I am far from).
Are there any fixes for this? Preferably a non-root fix ;)
I am running Debian 9.6.
EDIT: This was reported upstream and fixed!
Based on manp.c starting at line 786:
else if (sscanf (bp, "MANDATORY_MANPATH %511s", key) == 1)
add_mandatory (key);
else if (sscanf (bp, "MANPATH_MAP %511s %511s",
key, cont) == 2)
add_manpath_map (key, cont);
else if ((c = sscanf (bp, "MANDB_MAP %511s %511s",
key, cont)) > 0)
add_mandb_map (key, cont, c, user);
else if ((c = sscanf (bp, "DEFINE %511s %511[^\n]",
key, cont)) > 0)
add_def (key, cont, c, user);
else if (sscanf (bp, "SECTION %511[^\n]", cont) == 1)
add_sections (cont, user);
else if (sscanf (bp, "SECTIONS %511[^\n]", cont) == 1)
/* Since I keep getting it wrong ... */
...
I'd say the threshold is 511 characters. Interestingly there's a comment in the stating this should be fixed.
/* TODO: would like a (limited) replacement for sscanf()
* here that allocates its own memory. At that point check
* everything that sprintf()s manpath et al!
*/
References
man-db, the on-line manual database
man-db git repo
Related
I've written a couple production BPF agents, but my approach is very iterative until I please the verifier and can move on. I've reached my limit again.
Here's a program that works if I have one fewer && condition -- and breaks otherwise. The confusing part is that the warning implies that 103 insns is greater-than at most 4096 insns. There's obviously something I'm misunderstanding about how this is all strung together.
My ultimate goal is to do logging based on a process' environment -- so alternative approaches are welcome. :)
Error:
$ sudo python foo.py
bpf: Argument list too long. Program too large (103 insns), at most 4096 insns
Failed to load BPF program b'tracepoint__sched__sched_process_exec': Argument list too long
BPF Source:
#include <linux/mm_types.h>
#include <linux/sched.h>
#include <linux/version.h>
int tracepoint__sched__sched_process_exec(
struct tracepoint__sched__sched_process_exec* args
) {
struct task_struct* task = (typeof(task))bpf_get_current_task();
const struct mm_struct* mm = task->mm;
unsigned long env_start = mm->env_start;
unsigned long env_end = mm->env_end;
// Read up to 512 environment variables -- only way I could find to "limit"
// the loop to satisfy the verifier.
char var[12];
for (int n = 0; n < 512; n++) {
int result = bpf_probe_read_str(&var, sizeof var, (void*)env_start);
if (result <= 0) {
break;
}
env_start += result;
if (
var[0] == 'H' &&
var[1] == 'I' &&
var[2] == 'S' &&
var[3] == 'T' &&
var[4] == 'S' &&
var[5] == 'I' &&
var[6] == 'Z' &&
var[7] == 'E'
) {
bpf_trace_printk("Got it: %s\n", var);
break;
}
}
return 0;
}
Basic loader program for reproducing:
#!/usr/bin/env python3
import sys
from bcc import BPF
if __name__ == '__main__':
source = open("./foo.c").read()
try:
BPF(text=source.encode("utf-8")).trace_print()
except Exception as e:
error = str(e)
sys.exit(error)
bpf: Argument list too long. Program too large (103 insns), at most 4096 insns
Looking at the error message, my guess would be that your program has 103 instructions and it's rejected because it's too complex. That is, the verifier gave up before analyzing all instructions on all paths.
On Linux 5.15 with a privileged user, the verifier gives up after reading 1 million instructions (the complexity limit). Since it has to analyze all paths through the program, a program with a small number of instructions can have a very high complexity. That's particularly the case when you have loops and many conditions, as is your case.
Why is the error message confusing? This error message is coming from libbpf.c:
if (ret < 0 && errno == E2BIG) {
fprintf(stderr,
"bpf: %s. Program %s too large (%u insns), at most %d insns\n\n",
strerror(errno), attr->name, insns_cnt, BPF_MAXINSNS);
return -1;
}
Since the bpf(2) syscall returns E2BIG both when the program is too large and when its complexity is too high, libbpf prints the same error message for both cases, always with at most 4096 instructions. I'm confident upstream would accept a patch to improve that error message.
I am using Eclipse LDT for development, using the packaged Lua EE and Interpreter for Lua 5.2. I need to call the commandDatabase() method from my main method, though when I try, I receive the error:
"attempt to call global 'commandDatabase' (a nil value)".
I have looked up this error, and I am, as far as I can tell, defining methods in the right order.
Lua - attempt to call global 'contains' (a nil value)
When I view it in the debugger, the interpreter does not seem to find any methods I define between commandSystem and commandHelp. It shows each other function in the Variables area as e.g. ["commandSystem"] = function() but commandDatabase() does not appear
I have tried calling a wrapper method like so:
function commandDatabaseStep()
return commandDatabase()
end
... but this did not work either (same error)
The relevant code:
-- System command
function commandSystem()
...
end
-- Database command
function commandDatabase()
if arguments[2] == "no_arg1" then
print("The 'database' command must have at least one argument: [generate, wipe, dump, delete, get <system_name>]", true)
return 2
elseif arguments[2] == "generate" then
local file = io.open(database, "w+")
file:write("#ssmhub database")
file:close(file)
return 1
elseif arguments[2] == "dump" then
print("= DUMP START =")
for line in io.lines(database) do
print(line)
end
print("= DUMP END =")
return 1
-- 1+
elseif arguments[2] == "get" then
-- 2+
if isEmpty(arguments[3]) then
print("The 'database get' command must have a <name> parameter")
return 0
-- 2-
else -- 3+
local file = io.open(database, "r")
for line in io.lines(file) do -- 4+
local state = ""
local id = ""
local dividersFound = 0
line:gsub(".", function(c) -- 5+
if c == "|" then -- 6+
if dividersFound == 0 then -- 7+
state = state .. c
end -- 7-
if dividersFound == 1 then -- 8+
id = id .. c
end -- 8-
dividersFound = dividersFound + 1
end -- 6-
end) -- 5-
io.close(file)
end -- 4-
end -- 3-
else -- 9+
print("Illegal argument for command. Use 'help' for a list of commands and arguments.")
return 0
end -- 9-
end -- 2-
end -- 1-
function commandHelp()
...
end
-- Main
function main()
arguments = readProgramArguments()
commandArgument = arguments[1]
commandCompleteCode = 0
-- Process help and system commands
if commandArgument == "database" then
commandCompleteCode = commandDatabase()
end
end main()
As #luther pointed out, I had one-too-many end-s in commandDatabase.
This wasn't flagged in my IDE because I had not end-ed commandSystem, so commandSystem was nested inside of it.
To fix: add an end to commandSystem, and remove the end which I tagged '-- 1-'.
I have googled this a lot and I can only find answers that relate to conditions within the loop being met. I want this loop to run infinitely (Hence while 1==1) and I'm testing it at the moment by just leaving it running in Thonny. It runs for variable lengths of time and then just stops. It doesn't exit the program or stop running, it just behaves as if it's waiting for something but there's nothing that I can see that it's waiting for. The shell doesn't report any errors or report that it has stopped running, it simply stops printing the string in the fourth line print statement.
I am very new to python and Linux and I have no idea how to debug this problem or where to look for the stopping point. Even running it in debug mode doesn't render any helpful information. Has anyone got any suggestions please?
The only other thing that I have tried outside of what I have said is I have tried running it on a fresh install of Raspberry Pi OS on three different Raspberry Pi 4 Model B computers. It behaves exactly the same on all of them.
while 1==1:
time.sleep(1)
cnt = 1
print('One = One loop ' + str(datetime.today()) + ' CNT: ' + str(cnt))
while Decimal(target_temperature()) - Decimal(0.3) >= Decimal(actual_temperature()) and switch_state() == 'currently not running':
print('Before heating loop ' + str(datetime.today()))
try:
if cnt == 1:
if Decimal(target_temperature()) - Decimal(0.3) >= Decimal(actual_temperature()) and switch_state() == 'currently not running':
print('First heating loop ' + str(datetime.today()))
requests.get('http://192.168.1.167/4/on')
log_db('On', str(target_temperature()), str(actual_temperature()))
time.sleep(225)
requests.get('http://192.168.1.167/4/off')
log_db('Off', str(target_temperature()), str(actual_temperature()))
time.sleep(300)
cnt = cnt + 1
if(cnt != 1):
if Decimal(target_temperature()) - Decimal(0.3) >= Decimal(actual_temperature()) and switch_state() == 'currently not running':
print('Second heating loop ' + str(datetime.today()))
requests.get('http://192.168.1.167/4/on')
log_db('On', str(target_temperature()), str(actual_temperature()))
time.sleep(180)
requests.get('http://192.168.1.167/4/off')
log_db('Off', str(target_temperature()), str(actual_temperature()))
time.sleep(300)
except Exception as e:
print(e)
Bearing in mind i don't know anything about python i will try to help.
1 - The first thing i would do is put the whole program in a try catch block. That wasy if anything bad happens you should be told about it
try:
<all your code>
except Exception as e2:
print('The whole thing errored' + e2)
2 - The delays are in seconds? For testing i would change every sleep to (30) so you can see what is going on without getting too bored waiting, when you have it working then change the times back.
3 - I would add some more print('got here!') like where you have if(cnt == 1) add else print('first loop wasnt 1 it was ' + cnt)
4 - try and make the code easier for you to read, when it gets actually run it will be so optimized that it wont bear any relation to what you write. So write it in a way that is easiest for you
5 - You turn it on and then off, but if the off failed it would never be turned off, you should assume that it will go badly and that will be the day you get a big bill. Try and stop it if an error occurs by adding another check if actualTemp > targetTemp then turn it off?
6 - the http request might take ages, specify a time in seconds you are prepared to wait like , timeout=60
try:
while 1==1:
try:
time.sleep(30)
targetTemp = Decimal(target_temperature())
actualTemp = Decimal(actual_temperature())
switchState = switch_state()
print('Doing it at ' + str(datetime.now()) + ' target ' + str(targetTemp) + ' actual ' + str(actualTemp) + ' switch ' + switchState)
if targetTemp - Decimal(0.3) >= actualTemp and switchState == 'currently not running'
print('too cold turning it for a bit!')
requests.get('http://192.168.1.167/4/on', timeout=60)
log_db('On', targetTemp , actualTemp)
else if actualTemp > targetTemp and switchState != 'currently not running'
print('too hot turning it off!')
requests.get('http://192.168.1.167/4/off', timeout=60)
log_db('Off', targetTemp , actualTemp)
else
print('Not doing anything!')
except Exception as e1:
print('Loop errored -> ' + e1)
except Exception as e2:
print('Whole thing errored -> ' + e2)
Thanks Billy the Kid. You were right. Sometimes the devices that the loop uses via HTTPRequests just don't reapond (the two functions use HTTPRequests) and sometimes they create errors that aren't caught in the loop. Putting the whole thing in a try/catch oddly did identify that. Problem solved.
I am trying to write a configure.ac file to do these tasks:
The configure script should accept a --with-libuv parameter.
A variable with_libuv should be set to either yes, no or check (with check being the default value when nothing was passed on the command line).
When with_libuv == "yes" a mandatory PKG_CHECK_MODULES check for libuv >= 1.9.0 should be done and HAVE_LIBUV = 1 should be set on success (On error configure should abort).
When with_libuv == "no" nothing should be checked,
When with_libuv == "false" an optional PKG_CHECK_MODULES check (for the same library as in 3.) should be done and HAVE_LIBUV should be set to either 0 or 1 accordingly.
If with_libuv != "no" && HAVE_LIBUV == 1 AC_DEFINE should set -DUSE_LIBUV and AM_CONDITIONAL should set USE_LIBUV as a conditional for automake.
If not with_libuv != "no" && HAVE_LIBUV == 1 the preprocessor directive should not be set and the AM_CONDITIONAL should be set to 0.
I have figured out how to do steps 1-5, but I am struggeling with 6 and 7.
Here is my current attempt:
AC_INIT(
[mumble-pluginbot-plusplus],
[0.5],
[https://github.com/promi/mumble-pluginbot-plusplus/issues],
[],
[https://github.com/promi/mumble-pluginbot-plusplus])
AC_CONFIG_MACRO_DIR([m4])
AM_INIT_AUTOMAKE([foreign])
AM_SILENT_RULES([yes])
AC_PROG_CXX
LT_INIT
# Make sure that pkg-config is installed!
# The PKG_CHECK_MODULES macro prints a horrible error message when
# pkg-config is not installed at autogen time.
#
# It is also required when the first PKG_CHECK_MODULES is inside a conditional
PKG_PROG_PKG_CONFIG
PKG_CHECK_MODULES(OPUS, [opus >= 1.1])
PKG_CHECK_MODULES(OPENSSL, [openssl])
PKG_CHECK_MODULES(PROTOBUF, [protobuf])
PKG_CHECK_MODULES(MPDCLIENT, [libmpdclient])
AC_ARG_WITH(
[libuv],
[AS_HELP_STRING([--with-libuv], [support efficient MPD status polling #<:#default=check#:>#])],
[],
[with_libuv=check])
# if --with-libuv -> it must be installed
# elseif --without-libuv -> do nothing
# else -> check whether it is installed
AS_CASE(
["$with_libuv"],
[yes], [PKG_CHECK_MODULES(UV, [libuv >= 1.9.0], [HAVE_LIBUV=1])],
[no], [],
[PKG_CHECK_MODULES(UV, [libuv >= 1.9.0], [HAVE_LIBUV=1], [HAVE_LIBUV=0])])
if test "$with_libuv" != no -a "x$HAVE_LIBUV" -eq x1; then
AM_CONDITIONAL([USE_LIBUV], [1])
AC_DEFINE([USE_LIBUV], [1], [Define when libuv should be used.])
else
AM_CONDITIONAL([USE_LIBUV], [0])
fi
#AC_CONFIG_HEADERS([src/config.h])
AC_CONFIG_FILES([Makefile])
AC_OUTPUT
The problematic part is this:
if test "$with_libuv" != no -a "x$HAVE_LIBUV" -eq x1; then
AM_CONDITIONAL([USE_LIBUV], [1])
AC_DEFINE([USE_LIBUV], [1], [Define when libuv should be used.])
else
AM_CONDITIONAL([USE_LIBUV], [0])
fi
Here is an excerpt from the configure output:
checking pkg-config is at least version 0.9.0... yes
checking for OPUS... yes
checking for OPENSSL... yes
checking for PROTOBUF... yes
checking for MPDCLIENT... yes
checking for UV... yes
./configure: line 16467: test: x1: integer expression expected
./configure: line 16480: 0: command not found
checking that generated files are newer than configure... done
How can I implement steps 6 and 7 in a way that actually works?
You aren't aborting when yes fails (step 3). AM_CONDITIONAL should always be run. Step 6 says -DUSE_LIBUV, but your existing code will add -DUSE_LIBUV=1 to DEFS. Portable shell scripting considers test -a broken, so you shouldn't be using that. Your no case is equivalent to the check (or false) case where the search fails.
AS_CASE(
["$with_libuv"],
[yes], [PKG_CHECK_MODULES(UV, [libuv >= 1.9.0], [HAVE_LIBUV=1],
[AC_MSG_ERROR("libuv >= 1.9.0 is not installed")])],
[no], [HAVE_LIBUV=0],
[PKG_CHECK_MODULES(UV, [libuv >= 1.9.0], [HAVE_LIBUV=1],[HAVE_LIBUV=0])])
AS_IF([test "x$HAVE_LIBUV" = x1], [AC_DEFINE([USE_LIBUV])])
AM_CONDITIONAL([USE_LIBUV], [test "x$HAVE_LIBUV" = x1])
I think you should use = instead of -eq. The -eq is a relation between integers - the x1 isn't integer!
if test "$with_libuv" != no -a "x$HAVE_LIBUV" -eq x1; then
replace to
if test "$with_libuv" != no -a "x$HAVE_LIBUV" = x1; then
This should do the trick:
if test "$with_libuv" != no -a "x$HAVE_LIBUV" == x1; then
AC_DEFINE([USE_LIBUV], [1], [Define when libuv should be used.])
fi
AM_CONDITIONAL([USE_LIBUV], [test "$with_libuv" != no -a "x$HAVE_LIBUV" == x1])
It's a bit ugly, because the test is executed twice, but it seems to work ok.
I am quite an expert when it comes to programming in the MSL language, however I am unfamiliar with raw commands and whatnot.
I am in development of a new script. In this script I would like to check if $4 in what a user says is a registered nick or not but I do not know how to do this.
Thank you very much for any help and/or advice in advanced.
Best Regards,
Tim
Update:
raw 307:*:{ set $+(%,%chan,-,%CheckNick) Registered }
on *:TEXT:*:#:{
if ($1 == !regtest) {
set %chan $remove($chan,$chr(35))
set %CheckNick $4
whois $4
}
if ($($+(%,%chan,-,%CheckNick),$4),5) != $null) {
do this...
}
else {
else message...
}
}
I got this to work to check however my if statement to check if the variable has been set or not is being ignored...
Edit:
I tried using this:
checkNickReg $chan $2 $nick
...And echoing this:
echo -a Target: $1
echo -a Nick: $2
echo -a Status: $3
echo -a Chan: $3 - $chan
I'm trying to get a response to the channel such as; $nick $+ , $1 is not registered/registered/registered but not logged in.
What I've posted above is obviously wrong as it doesn't work, however I've tried a few methods and I'm actually not sure how the data is passed on with out the likes of tokenizing or setting variables...
Reply
[01:59:06] <~MrTIMarshall> !isReged mr-dynomite
[01:59:08] <&TornHQ> : mr-dynomite status is: NOTLOGGED
EDIT: mr-dynomite is not currently on, should this not = does not exist or does this check even when their not on, if so this is bloody brillant!!!
[02:00:04] <~MrTIMarshall> !isReged MrTIMarshall
[02:00:04] <&TornHQ> : MrTIMarshall status is: LOGGEDIN
$4 does not seem to work and what is the difference between 'exists, not logged in' and 'recognized, not logged in'?
Also, how does the data get passed on without setting variables or tokenizing?
(P.S. Thank you so much for the help you have dedicated so far!)
Another Edit:
I've been taking an in depth look today, am I correct in thinking if 0 or 1 the user is either not on-line or not registered (in the comments it says 0 = does not exists / not online, 1 = not logged in whereas 2 also says not logged in but recognized of which I'm unsure as what recognized means. Otherwise I'm very grateful for this script help and whatnot I'm just unclear on the numbers...
Since you have not specified any particular network I wrote an outline for some common networks around (that actually have user authentication systems). You should be able to add many other networks following the pattern.
Basically you execute /checkNickReg <target> <nick> [optional extra data] and when the server replays with the registration info (if applicable) use the on isReged signal event to handle the reply. Everything else is pretty much transparent.
EDIT: Looks like the specified network you are using (Torn) uses the standard anope services. So I updated the code to support that network.
; triggers when you get nick registration info back
; $1 = Target
; $2 = Nick
; $3 = Status, can be: LOGGEDIN, RECOGNIZED, NOTLOGGED
; $4- = Everything else passed
on *:signal:isReged:{
echo -a Target: $1
echo -a Nick: $2
echo -a Status: $3
echo -a Else: $4-
}
; reg lookup routines
alias checkNickReg {
set %reg. $+ $network 1
set %reg.target. $+ $network $1
set %reg.nick. $+ $network $2
set %reg.other. $+ $network $3-
; Freenode uses: NickServ ACC <nick>
if ($network == Freenode) msg NickServ ACC $2
; Rizon/SwiftIRC/OFTC/Torn use: NickServ STATUS <nick>
elseif ($istok(Rizon SwiftIRC OFTC Torn, $network, 32)) msg NickServ STATUS $2
}
; listen for replays
on *:notice:*:*:{
if ($($+(%, reg., $network),2)) {
;
var %target = $($+(%, reg.target., $network),2)
var %nick = $($+(%, reg.nick., $network),2)
var %other = $($+(%, reg.other., $network),2)
;
unset %reg*. $+ $network
if (($network == FreeNode) && ($2 == ACC)) $&
|| (($istok(Rizon SwiftIRC OFTC Torn, $network, 32)) && ($1 == STATUS)) {
; FreeNode:
; 0 = does not exist
; 1 = exists, not logged in
; 2 = recognized, not logged in
; 3 = logged in
; Rizon/SwiftIRC/OFTC/Torn:
; 0 = does not exists / not online
; 1 = not logged in
; 2 = recognized, not logged in
; 3 = logged in
if ($3 < 2) var %status = NOTLOGGED
elseif ($3 == 2) var %status = RECOGNIZED
else var %status = LOGGEDIN
}
;send status signal
.signal isReged %target %nick %status %other
}
}
(Extra Note: It might be useful to add an extra check to make sure $nick is AuthServ/NickServ for security reasons.)
A simple usage example is:
; Just a basic example of how to call it.
on *:text:!isReged &:#:{
checkNickReg $chan $2 $nick
}
on *:signal:isReged:{
msg $1 $4: $2 status is: $3
}
Type !isReged <nick>
Edit: The data gets passed to the on isReged event via global variables. I set them in the checkNickReg alias and I clean them up in the on notice event. So you never see them because they get cleaned up. They are passed to the isReged signal event in $1-.
On most IRCDs, it's only exposed in the WHOIS response for a user, if at all. Running a WHOIS every time a user says something is inadvisable, especially because server admins may receive a notification every time it happens.