Termux packages
===============
+[](https://travis-ci.org/termux/termux-packages)
[](https://gitter.im/termux/termux)
-This project contains scripts and patches to build packages for the
-[Termux](https://termux.com/) Android application.
+This project contains scripts and patches to build packages for the [Termux](https://termux.com/) Android application. Note that packages are cross compiled and that on-device builds are not currently supported.
-License
-=======
-The scripts and patches to build each package is licensed under the same license as
-the actual package (so the patches and scripts to build bash are licensed under
-the same license as bash, while the patches and scripts to build python are licensed
-under the same license as python).
+Setting up a build environment using Docker
+===========================================
+For most people the best way to obtain an environment for building packages is by using Docker. This should work everywhere Docker is supported (replace `/` with `\` if using Windows) and ensures an up to date build environment that is tested by other package builders.
-Build environment on Ubuntu 16.10
-=================================
-Packages are built using Ubuntu 16.10. Perform the following steps to configure a Ubuntu 16.10 installation:
-
-- Run `scripts/setup-ubuntu.sh` to install required packages and setup the `/data/` folder.
-
-- Run `scripts/setup-android-sdk.sh` to install the Android SDK and NDK at `$HOME/lib/android-{sdk,ndk}`.
-
-There is also a [Vagrantfile](scripts/Vagrantfile) available for setting up an Ubuntu environment using a virtual machine on other operating systems.
-
-Build environment using Docker
-==============================
-On other Linux distributions than Ubuntu 16.10 (or on other platforms than Linux) the best course
-of action is to setup a Docker container for building packages by executing:
-
- ./scripts/run-docker.sh # On Linux and macOS.
- .\scripts\run-docker.ps1 # On Windows.
+Run the following script to setup a container (from an image created by [scripts/Dockerfile](scripts/Dockerfile)) suitable for building packages:
-This will setup a container (from an image created by [scripts/Dockerfile](scripts/Dockerfile))
-suitable for building packages.
+ ./scripts/run-docker.sh
-This source folder is mounted as the /root/termux-packages data volume, so changes are kept
+This source folder is mounted as the `/root/termux-packages` data volume, so changes are kept
in sync between the host and the container when trying things out before committing, and built
deb files will be available on the host in the `debs/` directory just as when building on the host.
+The docker container used for building packages is a Ubuntu 17.10 installation with necessary packages
+pre-installed. The default user is a non-root user to avoid problems with package builds modifying the system
+by mistake, but `sudo` can be used to install additional Ubuntu packages to be used during development.
+
Build commands can be given to be executed in the docker container directly:
./scripts/run-docker.sh ./build-package.sh libandroid-support
command inside it and afterwards return you to the host prompt, with the newly built
deb in `debs/` to try out.
+Note that building packages can take up a lot of space (especially if `build-all.sh` is used to build all packages) and you may need to [increase the base device size](http://www.projectatomic.io/blog/2016/03/daemon_option_basedevicesize/) if running with a storage driver using a small base size of 10 GB.
+
+Build environment without Docker
+================================
+If you can't run Docker you can use a Ubuntu 17.10 installation (either by installing a virtual maching guest or on direct hardware) by using the below scripts:
+
+- Run `scripts/setup-ubuntu.sh` to install required packages and setup the `/data/` folder.
+
+- Run `scripts/setup-android-sdk.sh` to install the Android SDK and NDK at `$HOME/lib/android-{sdk,ndk}`.
+
+There is also a [Vagrantfile](scripts/Vagrantfile) available as a shortcut for setting up an Ubuntu installation with the above steps applied.
+
Building a package
==================
The basic build operation is to run `./build-package.sh $PKG`, which:
* scripts/check-pie.sh: Used for verifying that all binaries are using PIE, which is required for Android 5+.
-* scripts/detect-hardlinks.sh: Used for finding if any packages uses hardlinks, which does not work on Android M.
-
* scripts/check-versions.sh: used for checking for package updates.
* scripts/list-packages.sh: used for listing all packages with a one-line summary.
* [Beyond Linux From Scratch](http://www.linuxfromscratch.org/blfs/view/stable/)
-* [Cross-Compiled Linux From Scratch](http://www.clfs.org/view/CLFS-3.0.0-SYSVINIT/mips64-64/)
-
* [OpenWrt](https://openwrt.org/) as an embedded Linx distribution contains [patches and build scripts](https://dev.openwrt.org/browser/packages)
-* http://dan.drown.org/android contains [patches for cross-compiling to Android](http://dan.drown.org/android/src/) as well as [work notes](http://dan.drown.org/android/worknotes.html), including a modified dynamic linker to avoid messing with `LD_LIBRARY_PATH`.
-
* [Kivy recipes](https://github.com/kivy/python-for-android/tree/master/pythonforandroid/recipes) contains recipes for building packages for Android.
Common porting problems
=======================
-* The Android bionic libc does not have iconv and gettext/libintl functionality built in. A package from the NDK, libandroid-support, contains these and may be used by all packages.
+* The Android bionic libc does not have iconv and gettext/libintl functionality built in. A `libandroid-support` package contains these and may be used by all packages.
* "error: z: no archive symbol table (run ranlib)" usually means that the build machines libz is used instead of the one for cross compilation, due to the builder library -L path being setup incorrectly
-* rindex(3) is defined in <strings.h> but does not exist in NDK, but strrchr(3) from <string.h> is preferred anyway
+* rindex(3) does not exist, but strrchr(3) is preferred anyway.
* <sys/termios.h> does not exist, but <termios.h> is the standard location.
* <sys/fcntl.h> does not exist, but <fcntl.h> is the standard location.
-* glob(3) system function (glob.h) - not in bionic, but use the `libandroid-glob` package
-
-* [Cmake and cross compiling](http://www.cmake.org/Wiki/CMake_Cross_Compiling).
- `CMAKE_FIND_ROOT_PATH=$TERMUX_PREFIX` to search there.
- `CMAKE_FIND_ROOT_PATH_MODE_LIBRARY=ONLY` and `CMAKE_FIND_ROOT_PATH_MODE_INCLUDE=ONLY`
- for only searching there and don't fall back to build machines
-
-* Android is removing sys/timeb.h because it was removed in POSIX 2008, but ftime(3) can be replaced with gettimeofday(2)
+* <sys/timeb.h> does not exist (removed in POSIX 2008), but ftime(3) can be replaced with gettimeofday(2).
-* mempcpy(3) is a GNU extension. We have added it to <string.h> provided TERMUX_EXPOSE_MEMPCPY is defined,
- so use something like CFLAGS+=" -DTERMUX_EXPOSE_MEMPCPY=1" for packages expecting that function to exist.
+* <glob.h> does not exist, but is available through the `libandroid-glob` package.
-* Android uses a customized version of shared memory managemnt known as ashmem. libandroid-shmem wraps SYSV shared
- memory calls to standard ashmem operations. Use it with `LDFLAGS+=" -landroid-shmem`.
+* SYSV shared memory is not supported by the kernel. A `libandroid-shmem` package, which emulates SYSV shared memory on top of the [ashmem](http://elinux.org/Android_Kernel_Features#ashmem) shared memory system, is available. Use it with `LDFLAGS+=" -landroid-shmem`.
-* SYSV semaphores (semget(2), semop(2) and others) aren't available.
- Use unnamed POSIX semaphores instead (named semaphores are unimplemented).
+* SYSV semaphores is not supported by the kernel. Use unnamed POSIX semaphores instead (named semaphores are unimplemented).
dlopen() and RTLD_* flags
=================================
-<dlfcn.h> originally declares
+<dlfcn.h> declares
- enum { RTLD_NOW=0, RTLD_LAZY=1, RTLD_LOCAL=0, RTLD_GLOBAL=2, RTLD_NOLOAD=4}; // 32-bit
- enum { RTLD_NOW=2, RTLD_LAZY=1, RTLD_LOCAL=0, RTLD_GLOBAL=0x00100, RTLD_NOLOAD=4}; // 64-bit
+ RTLD_NOW=0; RTLD_LAZY=1; RTLD_LOCAL=0; RTLD_GLOBAL=2; RTLD_NOLOAD=4; // 32-bit
+ RTLD_NOW=2; RTLD_LAZY=1; RTLD_LOCAL=0; RTLD_GLOBAL=0x00100; RTLD_NOLOAD=4; // 64-bit
These differs from glibc ones in that
-1. They are not preprocessor #define:s so cannot be checked for with `#ifdef RTLD_GLOBAL`. Termux patches this to #define values for compatibility with several packages.
-2. They differ in value from glibc ones, so cannot be hardcoded in files (DLFCN.py in python does this)
-3. They are missing some values (`RTLD_BINDING_MASK`, `RTLD_NOLOAD`, ...)
+1. They differ in value from glibc ones, so cannot be hardcoded in files (DLFCN.py in python does this)
+2. They are missing some values (`RTLD_BINDING_MASK`, ...)
-RPATH, RUNPATH AND LD\_LIBRARY\_PATH
-====================================
-On desktop linux the linker searches for shared libraries in:
+Android Dynamic Linker
+======================
+The Android dynamic linker is located at `/system/bin/linker` (32-bit) or `/system/bin/linker64` (64-bit). Here are source links to different versions of the linker:
-1. `RPATH` - a list of directories which is linked into the executable, supported on most UNIX systems. It is ignored if `RUNPATH` is present.
-2. `LD_LIBRARY_PATH` - an environment variable which holds a list of directories
-3. `RUNPATH` - same as `RPATH`, but searched after `LD_LIBRARY_PATH`, supported only on most recent UNIX systems
+- [Android 5.0 linker](https://android.googlesource.com/platform/bionic/+/lollipop-mr1-release/linker/linker.cpp)
+- [Android 6.0 linker](https://android.googlesource.com/platform/bionic/+/marshmallow-mr1-release/linker/linker.cpp)
+- [Android 7.0 linker](https://android.googlesource.com/platform/bionic/+/nougat-mr1-release/linker/linker.cpp)
-The Android linker, /system/bin/linker, does not support RPATH or RUNPATH, so we set `LD_LIBRARY_PATH=$PREFIX/lib` and try to avoid building useless rpath entries (which the linker warns about) with --disable-rpath configure flags. NOTE: Starting from Android 7.0 RUNPATH (but not RPATH) is supported.
+Some notes about the linker:
-Warnings about unused DT entries
-================================
-Starting from 5.1 the Android linker warns about VERNEED (0x6FFFFFFE) and VERNEEDNUM (0x6FFFFFFF) ELF dynamic sections (WARNING: linker: $BINARY: unused DT entry: type 0x6ffffffe/0x6fffffff). These may come from version scripts (`-Wl,--version-script=`). The termux-elf-cleaner utilty is run from build-package.sh and should normally take care of that problem. NOTE: Starting from Android 6.0 symbol versioning is supported.
+- The linker warns about unused [dynamic section entries](https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-42444.html) with a `WARNING: linker: $BINARY: unused DT entry: type ${VALUE_OF_d_tag}` message.
+
+- The supported types of dynamic section entries has increased over time.
+
+- The Termux build system uses [termux-elf-cleaner](https://github.com/termux/termux-elf-cleaner) to strip away unused ELF entries causing the above mentioned linker warnings.
+
+- Symbol versioning is supported only as of Android 6.0, so is stripped away.
+
+- `DT_RPATH`, the list of directories where the linker should look for shared libraries, is not supported, so is stripped away.
+
+- `DT_RUNPATH`, the same as above but looked at after `LD_LIBRARY_PATH`, is supported only from Android 7.0, so is stripped away.
+
+- Symbol visibility when opening shared libraries using `dlopen()` works differently. On a normal linker, when an executable linking against a shared library libA dlopen():s another shared library libB, the symbols of libA are exposed to libB without libB needing to link against libA explicitly. This does not work with the Android linker, which can break plug-in systems where the main executable dlopen():s a plug-in which doesn't explicitly link against some shared libraries already linked to by the executable. See [the relevant NDK issue](https://github.com/android-ndk/ndk/issues/201) for more information.
~mdw / termux-packages / blobdiff