Programming Category - Page 39 of 43 - CNX Software

April 5, 2011 by Jean-Luc Aufranc (CNXSoft) - No Comments

C Code to get MAC Address and IP Address

Function in C to return the MAC Address:

/* Returns the MAC Address
   Params: int iNetType - 0: ethernet, 1: Wifi
           char chMAC[6] - MAC Address in binary format
   Returns: 0: success
           -1: Failure
    */
int getMACAddress(int iNetType, char chMAC[6]) {
  struct ifreq ifr;
  int sock;
  char *ifname=NULL;

  if (!iNetType) {
    ifname="eth0"; /* Ethernet */
  } else {
    ifname="wlan0"; /* Wifi */
  }
  sock=socket(AF_INET,SOCK_DGRAM,0);
  strcpy( ifr.ifr_name, ifname );
  ifr.ifr_addr.sa_family = AF_INET;
  if (ioctl( sock, SIOCGIFHWADDR, &amp;ifr ) &lt; 0) {
    return -1;
  }
  memcpy(chMAC, ifr.ifr_hwaddr.sa_data, 6)
  close(sock);
  return 0;
}

/* Returns the MAC Address

Params: int iNetType - 0: ethernet, 1: Wifi

char chMAC[6] - MAC Address in binary format

Returns: 0: success

-1: Failure

int getMACAddress(int iNetType, char chMAC[6]) {

struct ifreq ifr;

int sock;

char *ifname=NULL;

if (!iNetType) {

ifname="eth0"; /* Ethernet */

} else {

ifname="wlan0"; /* Wifi */

}

sock=socket(AF_INET,SOCK_DGRAM,0);

strcpy( ifr.ifr_name, ifname );

ifr.ifr_addr.sa_family = AF_INET;

if (ioctl( sock, SIOCGIFHWADDR, &ifr ) < 0) {

return -1;

}

memcpy(chMAC, ifr.ifr_hwaddr.sa_data, 6)

close(sock);

return 0;

}

Function in C to return the IP Address:

/* Returns the interface IP Address
   Params: int iNetType - 0: ethernet, 1: Wifi
           char *chIP - IP Address string
   Return: 0: success / -1: Failure
    */
int getIpAddress(int iNetType, char chIP[16]) {
  struct ifreq ifr;
  int sock = 0;

  sock = socket(AF_INET, SOCK_DGRAM, 0);
  if(iNetType == 0) {
    strcpy(ifr.ifr_name, "eth0");
  } else {
    strcpy(ifr.ifr_name, "wlan0");
  }
  if (ioctl(sock, SIOCGIFADDR, &amp;ifr) &lt; 0) {
    strcpy(chIP, "0.0.0.0");
    return -1;
 }
 sprintf(chIP, "%s", inet_ntoa(((struct sockaddr_in *) &amp;(ifr.ifr_addr))-&gt;sin_addr));
 close(sock);
 return 0;
}

/* Returns the interface IP Address

Params: int iNetType - 0: ethernet, 1: Wifi

char *chIP - IP Address string

Return: 0: success / -1: Failure

int getIpAddress(int iNetType, char chIP[16]) {

struct ifreq ifr;

int sock = 0;

sock = socket(AF_INET, SOCK_DGRAM, 0);

if(iNetType == 0) {

strcpy(ifr.ifr_name, "eth0");

} else {

strcpy(ifr.ifr_name, "wlan0");

}

if (ioctl(sock, SIOCGIFADDR, &ifr) < 0) {

strcpy(chIP, "0.0.0.0");

return -1;

}

sprintf(chIP, "%s", inet_ntoa(((struct sockaddr_in *) &(ifr.ifr_addr))->sin_addr));

close(sock);

return 0;

}

Jean-Luc Aufranc (CNXSoft)Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011. www.cnx-software.com

March 28, 2011 by Jean-Luc Aufranc (CNXSoft) - 19 Comments

Installing Linaro ARM Cross Toolchain on Ubuntu

You can easily install Linaro arm cross-compiler on Ubuntu 10.04 (Lucid), 10.10 (Maverick) and 11.04 (Natty) as follows: sudo apt-get install gcc-arm-linux-gnueabi This will install Linaro cross-toolchain version 4.4 on Ubuntu 10.04 and 10.10, and version 4.5 on Ubuntu 11.04. You can check the installation worked by checking the cross-compiler version jaufranc@CNX-TOWER:~$ arm-linux-gnueabi-gcc -v Using built-in specs. Target: arm-linux-gnueabi Configured with: ../src/configure -v –with-pkgversion=’Ubuntu/Linaro 4.4.4-14ubuntu4′ –with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs –enable-languages=c,c++,fortran,objc,obj-c++ –prefix=/usr –program-suffix=-4.4 –enable-shared –enable-multiarch –enable-linker-build-id –with-system-zlib –libexecdir=/usr/lib –without-included-gettext –enable-threads=posix –with-gxx-include-dir=/usr/arm-linux-gnueabi/include/c++/4.4.5 –libdir=/usr/lib –enable-nls –enable-clocale=gnu –enable-libstdcxx-debug –enable-objc-gc –disable-sjlj-exceptions –with-arch=armv7-a –with-float=softfp –with-fpu=vfpv3-d16 –with-mode=thumb –disable-werror –enable-checking=release –program-prefix=arm-linux-gnueabi- –includedir=/usr/arm-linux-gnueabi/include –build=i686-linux-gnu –host=i686-linux-gnu –target=arm-linux-gnueabi –with-headers=/usr/arm-linux-gnueabi/include –with-libs=/usr/arm-linux-gnueabi/lib Thread model: posix gcc version 4.4.5 (Ubuntu/Linaro 4.4.4-14ubuntu4) You can also install the latest version 4.5 (recommended) on Lucid and Maverick: sudo add-apt-repository ppa:linaro-maintainers/toolchain sudo apt-get update sudo apt-get install gcc-4.5-arm-linux-gnueabi If you are using an ARM platform running Ubuntu 10.10 or higher, you could also use the native GCC compiler. sudo apt-get install […]

March 21, 2011August 19, 2011 by Jean-Luc Aufranc (CNXSoft) - 8 Comments

Cross compiling Berkeley DB for ARM and MIPS

Following my blog entry about Databases for Linux Embedded Systems, here are the instructions to cross-compile Oracle Berkeley DB. First download the source code of the latest version of Berkeley DB (version 11gR2 – 11.2.5.1.25). You’ll need to register on Oracle website first on the download page http://www.oracle.com/technetwork/database/berkeleydb/downloads/index.html to download http://download.oracle.com/otn/berkeley-db/db-5.1.25.tar.gz (with AES encryption) or http://download.oracle.com/otn/berkeley-db/db-5.1.25.NC.tar.gz (if you don’t need encryption). Extract the source code: tar xzvf ../Downloads/db-5.1.25.tar.gz Configure and build the source code. I’ll use mipsel-linux-gcc, but any other cross-compiler could be used. cd db-5.1.25/build_unix ../dist/configure –host=mipsel-linux CC=mipsel-linux-gcc RANLIB=mipsel-linux-ranlib STRIP=mipsel-linux-strip AR=mipsel-linux-ar –prefix=/home/jaufranc/edev/lib/db-11g make make install The full berkeley DB package is 79MB: jaufranc@CNX-TOWER:~/edev/lib/db-11g$ du –max-depth=1 -h 6.6M ./lib 308K ./bin 72M ./docs 176K ./include 79M . However, you won’t need the include and docs directory in your embedded target. So you do not need to copy those. You may or may need the utilities in the bin file. The […]

March 14, 2011May 2, 2012 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

Cross compiling SQLite for ARM and MIPS

Following my blog entry about Databases for Linux Embedded Systems, here are the instructions to cross-compile SQlite. First download the latest version of SQLite amalgamation with autoconf script (version 3.75): wget http://www.sqlite.org/sqlite-autoconf-3070500.tar.gz Extract the source code: tar xzvf sqlite-autoconf-3070500.tar.gz Configure and build the source code. I’ll use mipsel-linux-gcc, but any other cross-compiler could be used. cd sqlite-autoconf-3070500 ./configure –host=mipsel-linux –target=mipsel-linux –prefix=/home/jaufranc/edev/sqlite-mips make make install At this point the library is correctly configured and installed, so you’d just need to copy the relevant files to your target board (skip include and share directories and libsqlite3.a) . Let’s check the size of the required files: ls -l ../sqlite-mips/bin/ -rwxr-xr-x 1 jaufranc jaufranc 125513 2011-03-14 14:21 sqlite ls -l ../sqlite-mips/lib/libsqlite3.so.0.8.6 -rwxr-xr-x 1 jaufranc jaufranc 2087584 2011-03-14 14:21 ../sqlite-mips/lib/libsqlite3.so.0.8.6 sqlite binary is 122.57KB and the dynamic library 2038.65KB. Let’s see if we can optimize the binary size with compilation flags and by disabling some […]

February 25, 2011 by Jean-Luc Aufranc (CNXSoft) - No Comments

Android C/C++ development with Android Native SDK

HyperDevBox is a Japanese based software development company, developing games for Android. They are presenting their new Android game called “Spectral Souls”, the first tactical RPG game for Android. The interesting part is that this Android gamewas not developped with Java, but only using C/C++ programming with Android Native SDK (NDK) (Currently revision 5). Using the NDK means you’ll have to adapt your software to several hardware platform contrary to java development. They now only support Qualcomm and PowerVR GPU for now, and they are working on supporting NVidia Tegra platform and other upcoming GPU. The advantage of native code is a potential performance improvement and code re-use if you have already applications developed in C/C++, the inconvenience is that more work is need to support different hardware. Currently the NDK is only available for ARM platforms (ARMv5TE andARMv7-A), future releases will support x86 instructions. The video below is an […]

February 7, 2011February 7, 2011 by Jean-Luc Aufranc (CNXSoft) - 1 Comment

Running .NET applications on Linux Embedded Systems

You may have some applications developed using Microsoft .NET application framework that are running on Windows XP, Windows Vista and Windows 7. .NET for Linux If after spending much effort and time, you have a request to port your application to Linux, you don’t need to rewrite everything thanks to Mono, an open source implementation of .NET framework that can be run in Windows, Linux and MacOS. The development framework is composed of three parts: Mono – An open source, cross-platform, implementation of C# and the CLR that is binary compatible with Microsoft.NET MonoDevelop – An open Source C# and .NET development environment for Linux, Windows, and Mac OS X Mono Tools for Visual Studio – Development Tools to develop and migrate .NET applications to Mono on Linux without leaving Visual Studio. This application can be tried for 30 days and / or purchased. This tools is compatible with Visual […]

February 4, 2011May 12, 2017 by Jean-Luc Aufranc (CNXSoft) - 23 Comments

Cross-compiling Python for MIPS and ARM Platforms

Python programming language is used in several open source projects such as Sugar OS and Xibo. Let’s see if we can cross-compile it in Ubuntu 10.10 using a mips compiler. I’ll use the instructions given at http://randomsplat.com/id5-cross-compiling-python-for-embedded-linux.html. Let’s download Python 2.7.1 first and extract the source code:

tar xjvf Python-2.7.1.tar.bz2

1	tar xjvf Python-2.7.1.tar.bz2

Then run the following command in Python-2.7.1 in order to build some tools for the host:

./configure
 make python Parser/pgen
 mv python hostpython
 mv Parser/pgen Parser/hostpgen
 make distclean

./configure

make python Parser/pgen

mv python hostpython

mv Parser/pgen Parser/hostpgen

make distclean

There is no patch for Python 2.7.1 cross-compilation in the link above, so let’s just try to configure and build it:

CC=mipsel-linux-gcc CXX=mipsel-linux-g++ AR=mipsel-linux-ar RANLIB=mipsel-linux-ranlib ./configure --host=mipsel-linux --target=mipsel-linux --prefix=/python
make HOSTPYTHON=./hostpython HOSTPGEN=./Parser/hostpgen BLDSHARED="mipsel-linux-gcc -shared" CROSS_COMPILE=mipsel-linux- CROSS_COMPILE_TARGET=yes

CC=mipsel-linux-gcc CXX=mipsel-linux-g++ AR=mipsel-linux-ar RANLIB=mipsel-linux-ranlib ./configure --host=mipsel-linux --target=mipsel-linux --prefix=/python

make HOSTPYTHON=./hostpython HOSTPGEN=./Parser/hostpgen BLDSHARED="mipsel-linux-gcc -shared" CROSS_COMPILE=mipsel-linux- CROSS_COMPILE_TARGET=yes

If we don’t use a patch the first error is:

Include/pyport.h:243:13: error: #error "This platform's pyconfig.h needs to define PY_FORMAT_LONG_LONG"

1	Include/pyport.h:243:13: error: #error "This platform's pyconfig.h needs to define PY_FORMAT_LONG_LONG"

So I used some older patch to create a new patch: http://www.cnx-software.com/patch/python-2.7.1-cross-compile.patch. You can download it an apply it as follows:

patch -p1 < python-2.7.1-cross-compile.patch

1	patch -p1 < python-2.7.1-cross-compile.patch

And repeat the step above to configure and cross-compile Python for mips. Finally install Python in ~/Python-2.7.1/install for example:

make install HOSTPYTHON=./hostpython BLDSHARED="mipsel-linux-gcc -shared" CROSS_COMPILE=mipsel-linux- CROSS_COMPILE_TARGET=yes prefix=~/Python-2.7.1/install

1	make install HOSTPYTHON=./hostpython BLDSHARED="mipsel-linux-gcc -shared" CROSS_COMPILE=mipsel-linux- CROSS_COMPILE_TARGET=yes prefix=~/Python-2.7.1/install

After that copy all necessary files in ~/Python-2.7.1/install to your […]

January 4, 2011January 24, 2012 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

Android App Inventor – Develop Android App Without Coding

[Update: Google phased out App Inventor, but made it open source. It is now hosted by MIT at http://appinventoredu.mit.edu/welcome-to-app-inventor-edu“] We have previously shown how to setup your environment to develop Android application using Eclipse. However, if you are not into Java programming and learning Android API but still want to develop (simple) Android applications, that’s still possible thanks to App Inventor. App Inventor will allow you to create the application UI in your web browser (The Designer), configure how your application behaves via a Java JNLP (Java Network Launching Protocol) applet (The Block Editor) and run your application in your Android phone/tablet or if you don’t have hardware in an emulator (The emulator). For Windows XP + Emulator, all you’ll have to do is to follow the instructions in http://appinventor.googlelabs.com/learn/setup/setupwindows.html and then you’ll be able to create some “Hello Kitty” application. First download the installer. Run appinventor_setup_installer_v_1_1.exe to install the […]