bionic/libc
The Android Open Source Project 4918d4cb0c am 611793d6: merge from open-source master
Merge commit '611793d6abcf504544d6ebccb8c46da06464b701'

* commit '611793d6abcf504544d6ebccb8c46da06464b701':
  Fix missing NL
2010-07-09 10:49:04 -07:00
..
arch-arm libc: fix fstatfs() implementation. 2010-07-08 16:52:27 -07:00
arch-sh libc: fix fstatfs() implementation. 2010-07-08 16:52:27 -07:00
arch-x86 merge from open-source master 2010-07-09 10:47:23 -07:00
bionic resolved conflicts for merge of 2576abf0 to master 2010-07-02 15:22:19 -07:00
docs libc: update alarm() implementation to return 0 on error. 2010-07-08 17:20:29 -07:00
include am ab8b5410: libc: fix fstatfs() implementation. 2010-07-08 17:22:08 -07:00
inet added missing ether_aton and ether_ntoa 2010-06-11 20:48:40 -04:00
kernel am 424d027b: merge from open-source master 2010-07-02 11:43:48 -07:00
netbsd Remove compiler warnings when building Bionic. 2010-06-22 17:51:41 -07:00
private Allow dlclose() to properly call static C++ destructors. 2010-07-01 23:09:28 -07:00
regex Remove compiler warnings when building Bionic. 2010-06-22 17:51:41 -07:00
stdio improve readability of stdio: fix indentation and remove trailing spaces 2010-05-17 09:34:13 -07:00
stdlib am cb0f5ed8: am 50ace4fe: Remove compiler warnings when building Bionic. 2010-06-23 12:41:50 -07:00
string Merge "string: tidy up strndup()" 2010-05-10 14:52:02 -07:00
tools modified SYSCALLS.TXT to support SuperH architecture 2009-09-01 19:03:06 +09:00
tzcode Remove compiler warnings when building Bionic. 2010-06-22 17:51:41 -07:00
unistd libc: update alarm() implementation to return 0 on error. 2010-07-08 17:20:29 -07:00
wchar wchar.h: improve wchar_t support in Bionic 2010-06-15 07:04:41 -07:00
zoneinfo Rebuild the time zone data files in 32-bit format instead of 64-bit. 2009-11-24 13:52:05 -08:00
Android.mk am 7ab9c068: am ab8b5410: libc: fix fstatfs() implementation. 2010-07-08 19:10:52 -07:00
CAVEATS auto import from //depot/cupcake/@135843 2009-03-03 19:28:35 -08:00
Jamfile auto import from //depot/cupcake/@135843 2009-03-03 19:28:35 -08:00
MODULE_LICENSE_BSD auto import from //depot/cupcake/@135843 2009-03-03 19:28:35 -08:00
NOTICE auto import from //depot/cupcake/@135843 2009-03-03 19:28:35 -08:00
README Add an 's and a . to the bionic/libc README. 2009-07-23 17:41:47 -07:00
SYSCALLS.TXT libc: fix fstatfs() implementation. 2010-07-08 16:52:27 -07:00

Welcome to Bionic, Android's small and custom C library for the Android
platform.

Bionic is mainly a port of the BSD C library to our Linux kernel with the
following additions/changes:

- no support for locales
- no support for wide chars (i.e. multi-byte characters)
- its own smallish implementation of pthreads based on Linux futexes
- support for x86, ARM and ARM thumb CPU instruction sets and kernel interfaces

Bionic is released under the standard 3-clause BSD License

Bionic doesn't want to implement all features of a traditional C library, we only
add features to it as we need them, and we try to keep things as simple and small
as possible. Our goal is not to support scaling to thousands of concurrent threads
on multi-processors machines; we're running this on cell-phones, damnit !!

Note that Bionic doesn't provide a libthread_db or a libm implementation.


Adding new syscalls:
====================

Bionic provides the gensyscalls.py Python script to automatically generate syscall
stubs from the list defined in the file SYSCALLS.TXT. You can thus add a new syscall
by doing the following:

- edit SYSCALLS.TXT
- add a new line describing your syscall, it should look like:

   return_type  syscall_name(parameters)    syscall_number

- in the event where you want to differentiate the syscall function from its entry name,
  use the alternate:

   return_type  funcname:syscall_name(parameters)  syscall_number

- additionally, if the syscall number is different between ARM and x86, use:

   return_type  funcname[:syscall_name](parameters)   arm_number,x86_number

- a syscall number can be -1 to indicate that the syscall is not implemented on
  a given platform, for example:

   void   __set_tls(void*)   arm_number,-1


the comments in SYSCALLS.TXT contain more information about the line format

You can also use the 'checksyscalls.py' script to check that all the syscall
numbers you entered are correct. It does so by looking at the values defined in
your Linux kernel headers. The script indicates where the values are incorrect
and what is expected instead.