From 798619b91c91405f847b0e48137239f218a4cf15 Mon Sep 17 00:00:00 2001 Message-Id: <798619b91c91405f847b0e48137239f218a4cf15.1718168789.git.mdw@distorted.org.uk> From: Mark Wooding Date: Sat, 13 Jun 2015 01:03:17 +0200 Subject: [PATCH] Initial push Organization: Straylight/Edgeware From: Fredrik Fornwall --- README.md | 133 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 131 insertions(+), 2 deletions(-) diff --git a/README.md b/README.md index 93b3b43c..181ed19e 100644 --- a/README.md +++ b/README.md @@ -1,2 +1,131 @@ -# termux-packages -Scripts and patches for building Termux packages +termux-packages +=============== +This project contains scripts and patches to cross compile and package packages for +the [Termux](http://termux.com/) Android application. + + +Overview +======== +In a non-rooted Android device an app such as Termux may not write to system locations, +which is why every package is installed inside the private file area of the Termux app: + PREFIX=/data/data/com.termux/files/usr + +For simplicity while developing and building, the build scripts here assume that a /data +folder is reserved for use on the host builder, which requires setup: + sudo mkdir /data + sudo chown $USER /data + +The basic flow is then to run "./build-package.sh $PKG", which + - Sets up a patched stand-alone Android NDK toolchain + - Reads packages/$PKG/build.sh to find out where to find the source code of the + package and how to build it. + - Applies all patches in packages/$PKG/\*.patch + - Builds the package and installs it to $PREFIX + - Packages the package in one or more .dpkg files for distribution +Reading and following build-package.sh is the best way to understand what's going on here. + +Additional utilities are contained here: + - build-all.sh, used for building all packages in the correct order (using buildorder.py) + - check-pie.sh, used for verifying that all binaries are using PIE, which is required for Android 5+ + - check-versions.sh, used for checking for package updates + - clean-rebuild-all.sh, used for doing a clean rebuild of all packages (takes a couple of hours) + - list-packages.sh, used for listing all packages with a one-line summary + + +Resources about cross-compiling packages +======================================== +* [Linux From Scratch](http://www.linuxfromscratch.org/blfs/view/svn/index.html) + +* [Beyond Linux From Scratch](http://www.linuxfromscratch.org/blfs/view/svn/) + +* [Cross-Compiled Linux From Scratch](http://cross-lfs.org/view/svn/x86_64-64/) + +* [OpenWrt](https://openwrt.org/), 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. + +* [CCTools](http://cctools.info/index.php?title=Main_Page) is an Android native IDE containing [patches for several programs](https://code.google.com/p/cctools/source/browse/#svn%2Ftrunk%2Fcctools-repo%2Fpatches) and [a bug tracker](https://code.google.com/p/cctools/issues/list). + +* [BotBrew](http://botbrew.com/) was a package manager for rooted devices with [sources on github](https://github.com/jyio/botbrew). Based on opkg and was transitioning to apt. + +* [Kivy recipes](https://github.com/kivy/python-for-android/tree/master/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. + +* "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 + +* <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 libglob package + +* undefined reference to 'rpl_malloc' and/or 'rpl_realloc': These functions are added by some autoconf setups + when it fails to detect 0-safe malloc and realloc during cross-compilating. Avoided by defining + "ac_cv_func_malloc_0_nonnull=yes ac_cv_func_realloc_0_nonnull=yes". + See http://wiki.buici.com/xwiki/bin/view/Programing+C+and+C%2B%2B/Autoconf+and+RPL_MALLOC + +* 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) + +* 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. + + +dlopen() and RTLD_* flags +================================= +<dlfn.h> declares + +> enum { RTLD_NOW = 2, RTLD_LAZY = 1, RTLD_LOCAL = 0, RTLD_GLOBAL = 0x00100, RTLD_NOLOAD = 4}; // 64 bit +> enum { RTLD_NOW = 0, RTLD_LAZY = 1, RTLD_LOCAL = 0, RTLD_GLOBAL = 2, RTLD_NOLOAD = 4}; // 32 bit + +These differs from glibc ones in that + +1. They are not preprocessor #define:s so cannot be checked for with #ifdef RTLD_GLOBAL (dln.c in ruby does this) +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, ...) + + +RPATH, LD_LIBRARY_PATH AND RUNPATH +================================== +On desktop linux the linker searches for shared libraries in: +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, e.g. on most current Linux systems +The Android linker (/system/bin/linker) does not support RPATH or RUNPATH, so we set LD_LIBRARY_PATH=$USR/lib and try to avoid building +useless rpath entries with --disable-rpath configure flags. +Another option to avoid depending on LD_LIBRARY_PATH would be supplying a custom linker - this is not done due to the overhead of maintaining a custom 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 arg ... + WARNING: linker: $BINARY: unused DT entry: type 0x6fffffff arg ... +These may come from version scripts in a Makefile such as: + -Wl,--version-script=$(top_srcdir)/proc/libprocps.sym +The termux-elf-cleaner utilty is run from build-package.sh and should normally take care of that problem. + + +Bootstrapping +============= +To get files on device one option is: + udpsvd -vE 0.0.0.0 8069 tftpd -c . # Run on device. -c arg to allow file uploading + printf "mode binary\nput out.md\nquit" | tftp 192.168.0.12 8069 # on computer +Another is with ftp: + tcpsvd -vE 0.0.0.0 8021 ftpd -w . # Run on device. -w arg to allow file uploading + printf "put tmp.c\nquit" | ftp -n 192.168.0.12 8021 # Run on computer. -n arg to use anonymous login +NOTE: The ftpd and tftpd programs has been patched to run without chroot. This means that the directory + serving is only the starting point and clients may cd out of if the access the whole system! + -- [mdw]