I'm building OpenWrt from source to run in QEMU for a research project. I want to use an x86-64 build since it will be a little easier for my purposes. when I go through the process of downloading and building all is successful except it won't run in qemu as the default CPU type is "pentium4".
As I understand OpenWrt the build configuration is stored in .config. The .config file is created/modified one of three ways:
make menuconfig
make kernel_config
make defconfig
I've used the search option in menuconfig and kernel_config and I see no setting for CONFIG_CPU_TYPE. I manually changed the setting as well as the associated options and get a successful build with target_i386_i486_musl.
I'd rather not modify .config directly if I don't have to. What is the correct way to change this setting?
Manually changing/adding parameter in .config won't help, as those parameters are not defined in the framework.
If you want to build it from the source then may be start by selecting
Target System (x86)
Subtarget (x86_64)
Target Profile (Generic)
in make menuconfig. OR
You can directly download the x86 image and use it(external links).
Related
According to How does AOSP 9.0 build system link the executable? and What does # mean in this clang command in AOSP build log? , when linking a module, AOSP seems to produce a .rsp file that contains all the obj files that the module need,and pass the file name as a parameter to the link command, for example:
prebuilts/clang/host/linux-x86/clang-4691093/bin/clang++ /OpenSource/Build/Android/9.0.0_r30/soong/.intermediates/bionic/libc/crtbegin_so/android_x86_64_core/crtbegin_so.o #/OpenSource/Build/Android/9.0.0_r30/soong/.intermediates/frameworks/base/libs/hwui/libhwui/android_x86_64_core_shared/libhwui.so.rsp ......
But the .rsp files seems to be removed after build.
The question is, how are these file generated and how to get these files? This may require to learn and modify the build scripts which is out of reach for me.
There maybe the answer for you, read the ninja build manual , in that manual .rsp file mentioned.
https://ninja-build.org/manual.html
the following is info that I copy out.
rspfile, rspfile_content
if present (both), Ninja will use a response file for the given command, i.e. write the selected string (rspfile_content) to the given file (rspfile) before calling the command and delete the file after successful execution of the command.
This is particularly useful on Windows OS, where the maximal length of a command line is limited and response files must be used instead.
I have cloned and built the waf script using:
./waf-light configure
Then to build my project (provided by Gomspace) I need to add waf and the eclipse.py to my path. So far I haven't found better than this setenv script:
WAFROOT=~/git/waf/
export PYTHONPATH=$WAFROOT/waflib/extras/:$PYTHONPATH
export PATH=~/git/waf/:$PATH
Called with:
source setenv
This is somehow a pretty ugly solution. Is there a more elegant way to install waf?
You don't install waf. The command you found correctly builds waf: /waf-light configure build Then for each project you create, you put the built waf script into that projects root directory. I can't find a reference, but this is the way in which waf:s primary author Thomas Nagy wants the tool to be used. Projects that repackage waf to make the tool installable aren't "officially sanctioned."
There are advantages and disadvantages with non-installation:
Disadvantages:
You have to add the semi-binary 100kb large waf file to your repository.
Because the file contains binary code, people can have legal objections to distributing it.
Advantages:
It doesn't matter if new versions of waf break the old API.
Users don't need to install waf before compiling the project -- having Python on the system is enough.
Fedora (at least Fedora 22) has a yum package for waf, so you could see that it's possible to do a system install of waf, albeit with a hack.
After you run something like python3 ./waf-light configure build, you'll get a file called waf that's actually a Python script with some binary data at the end. If you put it into /usr/bin and run it as non-root, you'll get an error because it fails to create a directory in /usr/bin. If you run it as root, you'll get the new directory and /usr/bin/waf runs normally.
Here's the trick that I learned from examining the find_lib() function in the waf Python script.
Copy the waf to /usr/bin/waf
As root, run /usr/bin/waf. Notice that it creates a directory. You'll see something like /usr/bin/.waf-2.0.19-b2f63c807a4215294bf6005410c74c18
mv that directory to /usr/lib, dropping the . in the directory name, e.g. mv /usr/bin/.waf-2.0.19-b2f63c807a4215294bf6005410c74c18 /usr/lib/waf-2.0.19-b2f63c807a4215294bf6005410c74c18
If you want to use waf with Python3, repeat Steps 2-3 running the Python script /usr/bin/waf under Python3. Under Python3, the directory names will start with .waf3-/waf3- instead instead of .waf-/waf-.
(Optional) Remove the binary data at the end of /usr/bin/waf.
Now, non-root should be able to just use /usr/bin/waf.
That said, here's something to consider, like what another answer said: I believe waf's author intended waf to be embedded in projects so that each project can use its own version of waf without fear that a project will fail to build when there are newer versions of waf. Thus, the one-global-version use case seems to be not officially supported.
I am working on a project that is transitioning from CMake to Bazel. One critical feature that we are apparently losing in the bargain is the ability to install the project, so that it can be used by other (not necessarily Bazel) projects.
AFAICT, there is currently no built in support for installing a project?!
I need to create a portable (must work on at least Linux and MacOS) way to install the project. Specifically:
I need to be able to specify libraries, headers, executables, and other files (e.g. LICENSE) that need to be installed.
The user needs to be able to specify an absolute prefix where things should be installed.
I really, really should be able to execute the "install" step more than once, giving different prefixes each time, without Bazel getting confused (i.e. it must not try to "remember" what files it already installed, or if it does, must understand when the prefix is different from last time).
Libraries should be installed to the right place (e.g. lib64), or at least it should be possible for the user to specify the correct libdir.
The install step MUST NOT touch the time stamp on any file from a previous install that has not changed. (Ideally, Bazel itself would handle this; using the install command is tricky and has potential portability issues. Note platform requirements, above.)
What is the best way to go about doing this?
Unless you want to do specific package (e.g. deb or rpm), you probably want to create an executable rule that does the install for you.
You can create a rule that would create an executable (e.g. a shell script) that does the install for you (e.g. do checksums to check if there are change to the installed file and does the actual copy of the files if they have changed). You would have to use the extension language to do, that would look similar to what the docker rules does to load an image with the incremental loader
Addition: I forgot to say that the install itself would be run by using the run command: bazel run install if the rule is named install in the top level BUILD file.
I'm building a Yocto image for a project but it's a long process. On my powerful dev machine it takes around 3 hours and can consume up to 100 GB of space.
The thing is that the final image is not "necessarily" the end goal; it's my application that runs on top of it that is important. As such, the yocto recipes don't change much, but my application does.
I would like to run continuous integration (CI) for my app and even continuous delivery (CD). But both are quite hard for now because of the size of the yocto build.
Since the build does not change much, I though of "caching" it in some way and use it for my application's CI/CD and I though of Docker. That would be quite interesting as I could maintain that image and share it with colleagues who need to work on the project and use it in CI/CD.
Could a custom Docker image be built for that kind of use?
Would it be possible to build such an image completely offline? I don't want to have to upload the 100GB and have to re-download it on build machines...
Thanks!
1. Yes.
I've used docker to build Yocto images for many different reasons, always with positive results.
2. Yes, with some work.
You want to take advantage of the fact that Yocto caches all the stuff you need to do your build in what it calls "Shared State Cache". This is normally located in your build directory under ${BUILDDIR}/sstate-cache, and it contains exactly what you are looking for in this case. There are a couple of options for how to get these files to your build machines.
Option 1 is using sstate mirrors:
This isn't completely offline, but lets you download a much smaller cache and build from that cache, rather than from source.
Here's what's in my local.conf file:
SSTATE_MIRRORS ?= "\
file://.* http://my.shared-computer.com/some-folder/PATH"
Don't forget the PATH at the end. That is required. The build system substitutes the correct path within the directory structure.
Option 2 lets you keep a local copy of your sstate-cache and build from that locally.
In your dockerfile, create the sstate-cache directory (location isn't important here, I like /opt for my purposes):
RUN mkdir -p /opt/yocto/sstate-cache
Then be sure to bindmount these directories when you run your build in order to preserve the contents, like this:
docker run ... -v /place/to/save/cache:/opt/yocto/sstate-cache
Edit the local.conf in your build directory so that it points at these folders:
SSTATE_DIR ?= "/opt/yocto/sstate-cache"
In this way, you can get your cache onto your build machines in whatever way is best for you (scp, nfs, sneakernet).
Hope this helps!
I'd like to know if there is any way to develop continuously with Trigger.io and avoid the forge build step with every file change I want to test in my browser or simulator.
I was faced with the same problem and I've got a working solution that uses watchr and watch to automatically rebuild each time I make a change to a source file. If you are running a "web" version of your app you can make a change to a source file and go directly to your browser and see the effect of your changes fairly quickly depending on how long the build takes.
Prerequisites: Ruby, watchr, Unix 'watch', and a terminal.
gem install watchr.
create a new ruby file for watchr to know what files to monitor and what to do when it sees a change. I named my file 'my_watch.rb': https://gist.github.com/3153167
open two terminals. Terminal 1 will run watchr and Terminal two will run 'forge build ...'.
In terminal 1 run 'watchr my_watch.rb' making sure the path to my_watch.rb is correct and make sure you've edited my_watch.rb according to your setup so that the path inside watch(...) reflects the files to be watched. My example watches all files in the same directory (and beneath) as the my_watch.rb script. You can place my_watch.rb in the 'src' folder of your Trigger.io app if you want to match my example and run watchr my_watch.rb directly from the src folder. Also not the shell command and path in the block need to be updated to reflect your environment. Again, in my example 'my_watch.rb' is inside 'src/' so when a change is detected we go up one directory and call 'forge build'.
I tend to develop actively with the 'web' version of my app so I can just open terminal 2 to my forge project directory and 'forge run web'. When I am testing in simulators and on devices, yes I have to run forge build every time I want to see a change. However, I typically don't have to wait for forge build to finish because watchr kicked off the build as soon as I made a change and it happens pretty quickly.
I know this is not an ideal solution but so far developing new features in the 'web' version first and then implementing in mobile versions has been very smooth for me. I've never needed to kill the 'web' version after a build but I maybe just lucky. As for running build each time you want to test the mobile versions if you are good with your keyboard shortcuts it really isn't bad at all. XCode makes you build and run after changes are made to source code when creating native iOS apps so I don't think Trigger is unique in requiring this build step.
I hope this helps and that my answer isn't too specific to me and my setup.
The build phase makes some changes to your source to enable the forge.* APIs - therefore, trying to just use the raw files in your src directory won't work.
You may be tempted to change files directly in the development directory, but this is a pretty bad idea: we delete those files with impunity when we need to!
We have plans on our medium-term roadmap to add a file-system watcher to start builds automatically when changes have occurred.
In the meantime, I just use forge build && forge run PLATFORM which tends to only take a few seconds...
while not perfect... this works for me.
go into development/web
rm src
link to your root src, ie ln -s ../../src src
copy the all.js from the web/forge and add to your index.html
ie
start nodemon web.js
open in browser.
note you will need to comment out the all.js script tag for non web builds.