Changes between Version 14 and Version 15 of AndroidBuildApp

Timestamp:

Nov 19, 2014, 4:26:14 PM (9 years ago)

Author:

davea

Comment:

--

AndroidBuildApp

@@ -2 +2 @@
 = How To Build BOINC Apps for Android =
 
-This document describes how to build BOINC apps
-for Android devices.
+This document describes how to build BOINC apps for Android devices.
 
 == Requirements ==
@@ -9 +8 @@
  * Android NKD: http://developer.android.com/tools/sdk/ndk/index.html
  * BOINC on Android build script: [http://boinc.berkeley.edu/trac/browser/boinc-v2/android]
-
 
 == Used versions ==
@@ -21 +19 @@
  * Android platform 2.3.4
 
-
 == Compatibility with BOINC on Android ==
 
-BOINC on Android runs on all Android devices, regardless of its CPU architecture.
-Possible architectures are ARM, x86 and MIPS. ARM is the predominant platform on Android.
+BOINC on Android runs on all Android devices, regardless of their CPU architecture.
+Possible architectures are ARM, x86 and MIPS.
+ARM is the dominant platform on Android.
 
 Even within ARM, higher ABIs or specific CPU capabilities might only be available
@@ -41 +39 @@
 ==  Setup NDK toolchain ==
 
-To set up a custom cross compilation toolchain,
-see article at AndroidBuildClient
-
+To set up a custom cross compilation toolchain, see AndroidBuildClient.
 
 == Build script ==
@@ -64 +60 @@
 }}}
 
-It's often useful to build a single executable that can support the vfp or neon libraries & instructions, and then use the BOINC APP_INIT_DATA and HOST_INFO structures to find the capabilities of the host and call the appropriate optimized routines (member variable 'p_features' e.g. strstr(aid.host_info.p_features, " neon ").  
+It's often useful to build a single executable that can support the vfp or neon libraries & instructions,
+and then use the BOINC APP_INIT_DATA and HOST_INFO structures
+to find the capabilities of the host and call the appropriate optimized routines
+(member variable 'p_features' e.g. strstr(aid.host_info.p_features, " neon ").  
 
-You can do this by selectively compiling using the above options, into separate small libraries that you link into the single executable, and use C++ namespaces to separate similar function calls.  Refer to the boinc/client/Makefile.am and client/whetstone.cpp, and client/cs_benchmark.cpp files for an example of how to do this.
+You can do this by selectively compiling using the above options,
+into separate small libraries that you link into the single executable,
+and use C++ namespaces to separate similar function calls.
+ Refer to the boinc/client/Makefile.am and client/whetstone.cpp, and client/cs_benchmark.cpp files
+ for an example of how to do this.
 
-== Fortran on Android NDK (optional build) ==
+== Position-independent executables (PIE) ==
+Starting with version 4.1, Android supports '''position-independent executables''' (PIE).
+Starting with version 5.0, PIE is mandatory - Android will refuse to run native executables
+that are not PIE.
 
-Note that the Android NDK currently does not have a fortran compiler distributed with it.  But it is possible to build GNU Fortran (gfortran) libraries for ARM/Android using the information at [http://danilogiulianelli.blogspot.co.uk/2013/02/how-to-build-gcc-fortran-cross-compiler.html]
+You can build PIE apps by including in your Makefile:
+{{{
+LOCAL_CFLAGS += -fPIE
+LOCAL_LDFLAGS += -fPIE -pie
+}}}
+
+== FORTRAN on Android NDK (optional build) ==
+
+The Android NDK currently does not have a FORTRAN compiler distributed with it.
+But it is possible to build GNU Fortran (gfortran) libraries for ARM/Android using the information at
+[http://danilogiulianelli.blogspot.co.uk/2013/02/how-to-build-gcc-fortran-cross-compiler.html]
 
 == Example ==
-Setup the environment: [http://boinc.berkeley.edu/trac/browser/boinc-v2/samples/example_app/build_android.sh]
+Setup the environment:
+[http://boinc.berkeley.edu/trac/browser/boinc-v2/samples/example_app/build_android.sh]
 
 Android Makefile: [http://boinc.berkeley.edu/trac/browser/boinc-v2/samples/example_app/Makefile_android]