In Yocto Dunfell, which recipe is writing out `/lib/systemd/system/getty#.service` - authentication

I would like to find the recipe writing out /lib/systemd/system/getty#.service so I can create an append.
First I tried to find out the creating package, which should be systemd:
$ oe-pkgdata-util find-path /lib/systemd/system/getty#.service
systemd: /lib/systemd/system/getty#.service
Thus, I looked up meta/recipes-core/systemd/systemd_244.3.bb (and the systemd.inc), but didn't find anything of value. Only the following line looked like a hit:
RDEPENDS_${PN} += "kmod dbus util-linux-mount util-linux-umount udev (= ${EXTENDPKGV}) util-linux-agetty util-linux-fsck"
This made the impression as if this file might get pulled in as a dependency, and is actually created by util-linux-agetty.
So I looked up the creating recipe:
$ oe-pkgdata-util lookup-recipe util-linux-agetty
util-linux
But in meta/recipes-core/util-linux/util-linux_2.35.1.bb and util-linux.inc I can't find creation of that file either.
I'm genuinely puzzled.
My image is equal to core-image-minimal except that it uses systemd as init manager.

Related

IntelliJ: Dynamically updated file header

By default, IntelliJ Idea will insert (something like) the following as the header of a new source file:
/**
* Created by JohnDoe on 2016-04-27.
*/
The corresponding template is:
/**
* Created by ${USER} on ${DATE}.
*/
Is it possible to update this template so that it inserts the last date of modification when the file is changed? For example:
/**
* Created by JohnDoe on 2016-03-27.
* Last modified by JaneDoe on 2016-04-27
*/
It is not supported out of the box. I suggest you do not include information about author and last edit/create time in file at all.
The reason is that your version control system (Git, SVN) contains the same information automatically. So the manual labelling is just duplicate of already existing info, but is only more error prone and needs to be manually updated.
Here's a working solution similar to what I'm using. Tested on mac os.
Create a bash script which will replace first occurrence of Last modified by JaneDoe on $DATE only if the exact value is not contained in the file:
#!/bin/bash
FILE=src/java/test/Test.java
DATE=`date '+%Y-%m-%d'`
PREFIX="Last modified by JaneDoe on "
STRING="$PREFIX.*$"
SUBSTITUTE="$PREFIX$DATE"
if ! grep -q "$SUBSTITUTE" "$FILE"; then
sed -i '' "1,/$(echo "$STRING")/ s/$(echo "$STRING")/$(echo "$SUBSTITUTE")/" $FILE
fi
Install File Watchers plugin.
Create a file watcher with appropriate scope (it may be this single file or any other scope, so that any change in project's source code will update modified date or version etc.) and put a path to your bash script into Program field.
Now every time the file changes the date will update. If you want to update date for each file separately, an argument $FilePath$ should be passed to the script.
This might have been just a comment to #oleg-mikhailov excellent idea, but the code snippet won't fit. Basically, I just tweaked his solution.
I needed a slightly different syntax but that's not the issue. The issue was that when the script ran automatically upon file save using the File Watchers plugin, if ran on a file which doesn't include PREFIX it would run over and over for ever.
I presume the that the issue is with the plugin itself, as it didn't happen when run from the shell, but I'm not sure why it happened.
Anyway, I ended up running the following script (as I said only a slight change with respect to the original). The new script also raises an error if the the prefix doesn't exist. For me this is a feature as Pycharm prompts me with the error, and I can fix the file.
Tested with PyCharm 2021.2.3 on macOS 11.6.
#!/bin/bash
FILE=$1
DATE=`date '+%Y-%m-%d'`
PREFIX="last_modified_date: "
STRING="$PREFIX.*$"
SUBSTITUTE="$PREFIX$DATE"
if ! grep -q "$SUBSTITUTE" "$FILE"; then
if grep -q "$PREFIX" "$FILE"; then
sed -i '' "s/$(echo "$STRING")/$(echo "$SUBSTITUTE")/" $FILE
else
echo "Error!"
echo "'$PREFIX' doesn't appear in $FILE"
exit 1
fi
fi
PHPStorm has not a "hook" for launching task after detect a change in file (just for uploading in server yes). Code templating is based on the creation of file not change.
The behaviour you want (automatic change file after manual change file) can be useful for lot of things but it's circular headhache for editor. Because if you change a file it must change file (and if a file is change ? it change file ?).
However, You can, perhaps, "enable Live Templates" when you launch a "reformat code" which able to rewrite your begin template code that way rewrite date modification.
Other solution is that use a tools with as grunt but I don't know if manage php file.

Testing net/http?

I am a little confused about how to structure a go web app and its tests. I have read the How to Write Go Code but still don't get it. For example, I have a go project called "beacon" with a beacon.go file at the root. Adding a trivial beacon_test.go file (copied verbatim from http://golang.org/pkg/net/http/httptest/#example_Server) causes this error:
$ go test
# github.com/jelder/beacon
./beacon_test.go:11: main redeclared in this block
previous declaration at ./beacon.go:216
FAIL github.com/jelder/beacon [build failed]
Sure enough, line 11 is func main(). If I instead change the package main line in my beacon_test.go to package hello, I get this error instead:
can't load package: package github.com/jelder/beacon: found packages main (beacon.go) and hello (beacon_test.go) in /Users/jacob/src/github.com/jelder/beacon
beacon_test.go has also a function called main() rename it to TestFirst (or any other name you like as long as it starts with Test, note the uppercase T is important). There is no need for that. Just run go test . from inside the package you are working on (the one containing the *.go files). Post the full files if you need more help.

How to add a user defined function in QDB Library?

QDB is a database provided by QNX Neutrino package. I went through the QDB documentation to add a user defined SQL function: http://www.qnx.com/developers/docs/6.5.0/topic/com.qnx.doc.qdb_en_dev_guide/writing_functions.html?cp=2_0_8
I created a source file which had my user define SQL function written in C and qdb_function structure definition. I built it with a make file to create libudf.so.
As suggested by QDB I added Function = udftag#libudf.so in the qdb.cfg. But while running the qdb in the shell prompt, it is giving the error (in bold):
qdb -I basic -V -R set -v -c /etc/sql/qdb.cfg -s de_DE#cldr -o tempstore=/fs/tmpfs
QDB: No script registered for handling corrupt database.
qdb: processing [TempMainAddressBook]Function - Can't access shared library
and qdb is getting exited immediately.
I have tried following things:
made sure sqlite3 library is added in the make file
source code is in strictly in C by using directive : extern "C" to avoid name mangling as the file extension is .cpp. I also tried with .c extension.
given the absolute path of the libudf.so in qdb.cfg as : Function = udftag#/usr/lib/libudf.so
qdb_funcion struct is properly defined in library's source code only.
tried without using the static declaration of function(mentioned in the qdb docs)
After trying all hits and trials also, I am getting the same error every time which is Can't access shared library
If any one has any idea to resolve this error please share.
Suggestion 1: run qdb by setting LD_DEBUG=1, like in:
LD_DEBUG=1 qdb command line options
This will output a lot of debug information from the dynamic loader as it attempts to locate and then load the .so files. Check what is the path that it output before the "Can't access" message is displayed.
Suggestion 2: obvious but make sure that the permissions are OK for the .so file. Do you have the execution permission set?
Suggestion 3: check if the error message is identical if you completely remove the .so file from the system
Suggestion 4: increase the number of lower-case 'v'-s. QDB likely supports more, with progressively more verbose information provided as you increase the numbers (6 should be enough for full verbosity)

How to force STORE (overwrite) to HDFS in Pig?

When developing Pig scripts that use the STORE command I have to delete the output directory for every run or the script stops and offers:
2012-06-19 19:22:49,680 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 6000: Output Location Validation Failed for: 'hdfs://[server]/user/[user]/foo/bar More info to follow:
Output directory hdfs://[server]/user/[user]/foo/bar already exists
So I'm searching for an in-Pig solution to automatically remove the directory, also one that doesn't choke if the directory is non-existent at call time.
In the Pig Latin Reference I found the shell command invoker fs. Unfortunately the Pig script breaks whenever anything produces an error. So I can't use
fs -rmr foo/bar
(i. e. remove recursively) since it breaks if the directory doesn't exist. For a moment I thought I may use
fs -test -e foo/bar
which is a test and shouldn't break or so I thought. However, Pig again interpretes test's return code on a non-existing directory as a failure code and breaks.
There is a JIRA ticket for the Pig project addressing my problem and suggesting an optional parameter OVERWRITE or FORCE_WRITE for the STORE command. Anyway, I'm using Pig 0.8.1 out of necessity and there is no such parameter.
At last I found a solution on grokbase. Since finding the solution took too long I will reproduce it here and add to it.
Suppose you want to store your output using the statement
STORE Relation INTO 'foo/bar';
Then, in order to delete the directory, you can call at the start of the script
rmf foo/bar
No ";" or quotations required since it is a shell command.
I cannot reproduce it now but at some point in time I got an error message (something about missing files) where I can only assume that rmf interfered with map/reduce. So I recommend putting the call before any relation declaration. After SETs, REGISTERs and defaults should be fine.
Example:
SET mapred.fairscheduler.pool 'inhouse';
REGISTER /usr/lib/pig/contrib/piggybank/java/piggybank.jar;
%default name 'foobar'
rmf foo/bar
Rel = LOAD 'something.tsv';
STORE Rel INTO 'foo/bar';
Once you use the fs command, there a lot of ways to do this. For an individual file, I wound up adding this to the beginning of my scripts:
-- Delete file (won't work for output, which will be a directory
-- but will work for a file that gets copied or moved during the
-- the script.)
fs -touchz top_100
rm top_100
For a directory
-- Delete dir
fs -rm -r out

Git - how do I view the change history of a method/function?

So I found the question about how to view the change history of a file, but the change history of this particular file is huge and I'm really only interested in the changes of a particular method. So would it be possible to see the change history for just that particular method?
I know this would require git to analyze the code and that the analysis would be different for different languages, but method/function declarations look very similar in most languages, so I thought maybe someone has implemented this feature.
The language I'm currently working with is Objective-C and the SCM I'm currently using is git, but I would be interested to know if this feature exists for any SCM/language.
Recent versions of git log learned a special form of the -L parameter:
-L :<funcname>:<file>
Trace the evolution of the line range given by "<start>,<end>" (or the function name regex <funcname>) within the <file>. You may not give any pathspec limiters. This is currently limited to a walk starting from a single revision, i.e., you may only give zero or one positive revision arguments. You can specify this option more than once.
...
If “:<funcname>” is given in place of <start> and <end>, it is a regular expression that denotes the range from the first funcname line that matches <funcname>, up to the next funcname line. “:<funcname>” searches from the end of the previous -L range, if any, otherwise from the start of file. “^:<funcname>” searches from the start of file.
In other words: if you ask Git to git log -L :myfunction:path/to/myfile.c, it will now happily print the change history of that function.
Using git gui blame is hard to make use of in scripts, and whilst git log -G and git log --pickaxe can each show you when the method definition appeared or disappeared, I haven't found any way to make them list all changes made to the body of your method.
However, you can use gitattributes and the textconv property to piece together a solution that does just that. Although these features were originally intended to help you work with binary files, they work just as well here.
The key is to have Git remove from the file all lines except the ones you're interested in before doing any diff operations. Then git log, git diff, etc. will see only the area you're interested in.
Here's the outline of what I do in another language; you can tweak it for your own needs.
Write a short shell script (or other program) that takes one argument -- the name of a source file -- and outputs only the interesting part of that file (or nothing if none of it is interesting). For example, you might use sed as follows:
#!/bin/sh
sed -n -e '/^int my_func(/,/^}/ p' "$1"
Define a Git textconv filter for your new script. (See the gitattributes man page for more details.) The name of the filter and the location of the command can be anything you like.
$ git config diff.my_filter.textconv /path/to/my_script
Tell Git to use that filter before calculating diffs for the file in question.
$ echo "my_file diff=my_filter" >> .gitattributes
Now, if you use -G. (note the .) to list all the commits that produce visible changes when your filter is applied, you will have exactly those commits that you're interested in. Any other options that use Git's diff routines, such as --patch, will also get this restricted view.
$ git log -G. --patch my_file
Voilà!
One useful improvement you might want to make is to have your filter script take a method name as its first argument (and the file as its second). This lets you specify a new method of interest just by calling git config, rather than having to edit your script. For example, you might say:
$ git config diff.my_filter.textconv "/path/to/my_command other_func"
Of course, the filter script can do whatever you like, take more arguments, or whatever: there's a lot of flexibility beyond what I've shown here.
The closest thing you can do is to determine the position of your function in the file (e.g. say your function i_am_buggy is at lines 241-263 of foo/bar.c), then run something to the effect of:
git log -p -L 200,300:foo/bar.c
This will open less (or an equivalent pager). Now you can type in /i_am_buggy (or your pager equivalent) and start stepping through the changes.
This might even work, depending on your code style:
git log -p -L /int i_am_buggy\(/,+30:foo/bar.c
This limits the search from the first hit of that regex (ideally your function declaration) to thirty lines after that. The end argument can also be a regexp, although detecting that with regexp's is an iffier proposition.
git log has an option '-G' could be used to find all differences.
-G Look for differences whose added or removed line matches the
given <regex>.
Just give it a proper regex of the function name you care about. For example,
$ git log --oneline -G'^int commit_tree'
40d52ff make commit_tree a library function
81b50f3 Move 'builtin-*' into a 'builtin/' subdirectory
7b9c0a6 git-commit-tree: make it usable from other builtins
The correct way is to use git log -L :function:path/to/file as explained in eckes answer.
But in addition, if your function is very long, you may want to see only the changes that various commit had introduced, not the whole function lines, included unmodified, for each commit that maybe touch only one of these lines. Like a normal diff does.
Normally git log can view differences with -p, but this not work with -L.
So you have to grep git log -L to show only involved lines and commits/files header to contextualize them. The trick here is to match only terminal colored lines, adding --color switch, with a regex. Finally:
git log -L :function:path/to/file --color | grep --color=never -E -e "^(^[\[[0-9;]*[a-zA-Z])+" -3
Note that ^[ should be actual, literal ^[. You can type them by pressing ^V^[ in bash, that is Ctrl + V, Ctrl + [. Reference here.
Also last -3 switch, allows to print 3 lines of output context, before and after each matched line. You may want to adjust it to your needs.
Show function history with git log -L :<funcname>:<file> as showed in eckes's answer and git doc
If it shows nothing, refer to Defining a custom hunk-header to add something like *.java diff=java to the .gitattributes file to support your language.
Show function history between commits with git log commit1..commit2 -L :functionName:filePath
Show overloaded function history (there may be many function with same name, but with different parameters) with git log -L :sum\(double:filepath
git blame shows you who last changed each line of the file; you can specify the lines to examine so as to avoid getting the history of lines outside your function.