I am trying to use device mapper in Android, but still stuck on the command "dmsetup" didn't found in Android.
I have loaded the linear.ko and zero.ko which are target device classes successfully in my Android device, but cannot create a virtual device by device mapper because "dmsetup" cannot be found. If anyone know how to get one for Android or have any other methods to create a virtual device?
By the way, I saw a file "device-mapper" in /dev folder, what is used for?
I am really appreciate who can help me on this.
BR,
-Wenji
There is an API that you can use programatically to talk to the device mapper: http://lwn.net/Articles/35077/
This is based around ioctl(), so it's not the friendliest, but it's pretty well documented: http://androidxref.com/4.4.4_r1/xref/bionic/libc/kernel/common/linux/dm-ioctl.h
There is a great example of its use at: https://github.com/nelenkov/cryptsetup, albeit focussed on dm-verity.
Related
I have a K1 Plus android box which have a built-in dvb-t2` and dvb-s2 tuner in it. I want to create an app that gets and shows the channels from those tuners.
At first, I found about android's TV Input Framework(TIF). The sample app keeps crashing by calling a method that gets the available inputs of the device. Then, found out that it only work for real Android TVs. I looked for android libraries for that android box but didn't find anything. I looked for c libraries that can access the tuners but didn't find anything as well. I looked for code on how to access the hardware components of an android device and didn't find anything. I recently found about https://opencv.org/. I haven't read everything about it yet so I don't really know how to use it.
I found about https://git.linuxtv.org/v4l-utils.git from an answer to a SO question but it seems like it can only be used after installing it to an OS. I was able to compile it using CMake on android but it got missing header files.
I also found http://android4tv.iwedia.com. Unfortunately, it's also using TIF.
I'm trying to create something like kodi but I found out that it isn't really the one that gets the channels but kodi is getting it from a supported iptv box. I have zero knowledge about writing C but I'll try to make the code.
This is the box btw. http://www.videostrong.com/S905D+DVB(KI%20PLUS)/55.html
From my research, I found about HAL(Hardware Abstraction Layer). Do I need that for making my C code?
Update:
After months of research and not finding any quick way to implement a tv tuner library, I returned to my bookmarks from previous research. One of them is this. The first step from that SO answer is do a ls /dev/dvb/ on the device. Because I need to do it on the android box itself, I researched about android terminal apps and found Termux. Then I did the ls /dev/dvb/ command on Termux and it told that the resource was not found or it did not exist. Then I tried to just do a ls /dev/ command and luckily I got results. There's quite a lot of them and I found something related to dvb.
The dvb related results were:
dvb0.demux0
dvb0.demux1
dvb0.demux2
dvb0.dsc0
dvb0.dsc1
dvb0.dvr0
dvb0.dvr1
dvb0.dvr2
dvb0.net0
dvb0.net1
dvb0.net2
I can post the whole list but I'll post this more related (I think) results.
The results are quite different than the example of the link above because they only used dvb and not dvb0.
UPDATE:
I might use a usb tv tuner now based on a suggestion to me.
UPDATE:
Is there a list of standard and tv tuner related usb byte[] commands that I can look at? I already saw some but they are mostly for FTDI, serial or the really standard commands which I don't have really have any use.
It will probably take a lot of reverse engineering or a leaked documentation to achieve what you are trying to do.
Devices like the one you are working on usually use proprietery hardware with proprietery drivers for things like DVB, so making a third party app for a TV tuner is very hard.
First, you need to find out what kind of DVB chip / card this Android box has.
Then, you need to figure out how (on what kind of BUS) it is connected to the system.
If it is something generic, you may be able to talk to its driver, if not, you would need to write your own driver.
This is too complicated to explain in a SO post, but you could start by opening the box and looking at the components or by running commands like lsusb through ADB to try and identify the DVB component.
If the device already has a DVB app, you could try disassembling it, to find out how it works.
Good luck!
In my Android application, I let the user choose a Wifi connection for the device. Using WifiConfiguration, I am able to deal with WEP as well as WPA2-PSK networks. However, it appears WPA2-EAP requires one more field - username. Browsing the net, I came across a system class WifiEnterpriseConfig that seems promising. However, this API is available only for OS 4.3+. I am wondering if there is any other way to achieve saving EAP network config that would work for 4.1 and above. Any pointer is appreciated. Regards.
You can just copypaste source code of this class into your project, it should resolve your problem.
How to connect Wii balance board with android?
Is there are any useful Library in android and how to use it?
My goal now is to connect it together and can receive data from it.
I'm new with android and Bluetooth development
I found this answer useful: Is it possible for an android device to read information from the wii controller and nunchuck? (quoted below with thanks to #Ben Mordue)
Have a look at this open source project:
http://code.google.com/p/android-bluez-ime/
Update:
I first installed the APK file on Galaxy Nexus and it works. I have checked the code out of the repo, and it builds fine, and it relatively easy to understand.
It comes in 3 projects - to use Wiimote, you need to install all 3 projects. The one is just used as a flag to allow the service to try for a Wiimote (considering not all ROMs support that level of HID interaction).
I also found these resources on WiiBrew.org:
http://wiibrew.org/wiki/Wiimote
http://wiibrew.org/wiki/Wii_Balance_Board
I used the Wiimote link to understand the Bluez-IME code.
Update 2:
Last night I got the board to communicate with my Android phone correctly. I did this by starting with the Bluez-IME code linked above, and modifying it based on the wiibrew.org info.
The trick is that the Balance Board is like a wiimote with an Extension. So its like a Nunchuk or Classic Controller, but just with a different device ID to look for.
For my initial demo, I just searched for all code that uses a Nunchuk, and duplicated it for a Balance Board. Then to initialise the MODE to use channel 0x32, as per the wiibrew Balance Board page.
Update 3:
I just stumbled across this app on the store: FitScales
And the developer has shared his code on github: paulburton / fitscales
I m looking for info about ndk so to read network data (neightbor cell, ec/io, bcch) for galaxy s . Any1 know some hidden api to write something ?
I know api exist, because there is some professional app used in tlc to use galaxy in netfield process (see qualipoc app for android)
thanks
You don't need hidden API to access telephony information. And NDK is not going to help you in this. See for example http://developer.android.com/reference/android/telephony/NeighboringCellInfo.html
Is there any neat way of accessing screenshot of android device
programatically. I am looking for some 15-20fps.
I found one code
android\generic\frameworks\base\services\surfaceflinger\tests\screencap\scr eencap.cpp,
i built the executable and put it in /data and changed the mode 777
but when i tried to execute it using adb shell it gives the below error.
# chmod 777 test-screencap
chmod 777 test-screencap
# ./test-screencap test
./test-screencap test
screen capture failed: Function not implemented
I also know that we can access fb0 but its not a right method as suggested
by android team. Is it possible to access the screen shot at the frameworks
layer. I beleive surface flinger composes individual layers and gives it to
framebuffer.Where exactly this is done ? Can a application be able to access
such codes.
There are some java apps also which use ddms to actually capture this
framebuffer data without root access. But the fps is really poor.
I beleive there should be some or the other way of doing the above job.
Please suggest me some neat way of doing it. Suggestions are welcome.
What you are trying to do is not possible if you don't have a rooted phone, there is an app out there that does what you are trying, Screenshot ER. The latest OEM's are putting it into their /system/apps now... so you may be able to use their apps, check out this article for devices that have enabled this feature. Other than that your really stuck but there are implications with screen captures enabled as this could lead apps saving screen captures and sending that info out, enabling virus type apps...
Information for others .....Through Eclipse you can get a screen capture usig the DDMS perspective. If you take a look at the Eclipse DDMS code base its actually a stand-alone app too. You might be able to use this Java code then.
AdbHelper.getFrameBuffer(AndroidDebugBridge.getSocketAddress(), this);
Take a look at droid VNC Server
This is an open source project which you can clone the source code to your private PC. (http://github.com/oNaiPs/droid-VNC-server). I am investigating how VNC can do but It's really hard to do the same.
Read framebuffer content is an good solution also. But it just work with android <3.x only. I don't know how to fix it to work on android 4.x. If you know how (after see my suggestion) please share it here. Through my researching, I see that there are a lot of people looking for this.
Hope this helps.
nguyenminhbinh1602#gmail.com.
Android Freelancer.