bionic/libc
Elliott Hughes 1302f6936b am fdb11929: am b88f810d: Merge "Update to tzdata2012c."
* commit 'fdb119297ac421e2fc2ec096a6d5370b81938de8':
  Update to tzdata2012c.
2012-04-02 16:09:36 -07:00
..
arch-arm Update kernel headers and add syscall "perf_event_open" 2012-03-13 12:28:40 -07:00
arch-sh/syscalls Merge c4cb87f3 2012-02-01 09:46:08 -08:00
arch-x86 am cd834618: am 63b14755: Merge "libc/x86: ensure the stack 16-byte aligned when tasks created" 2012-03-30 22:16:02 -07:00
bionic Handle pthread-related changes (mutex/atfork) 2012-03-26 15:38:59 -07:00
docs libc: Fix the definition of SIGRTMAX 2010-12-20 15:58:06 +01:00
include Merge "string.h: add __attribute__ ((pure)) to string functions" 2012-03-21 14:40:41 -07:00
inet Fix build. 2011-06-09 13:03:17 -07:00
kernel Revert "libc/kernel: Add rules to autogenerate device specific kernel headers" 2012-03-30 10:21:25 -07:00
netbsd Use new binary code format 2012-03-09 11:50:46 -08:00
private Handle pthread-related changes (mutex/atfork) 2012-03-26 15:38:59 -07:00
regex Remove compiler warnings when building Bionic. 2010-06-22 17:51:41 -07:00
stdio libc: speed-up flockfile()/funlockfile() 2011-11-15 13:16:42 +01:00
stdlib Enable functional DSO object destruction 2011-07-07 22:51:43 +02:00
string string: Fix wrong comparison semantics 2011-12-05 18:37:10 -08:00
tools Update to tzdata2012c. 2012-04-02 07:43:15 -07:00
tzcode libc: remove private declarations from <time.h> and <resolv.h> 2012-01-13 14:24:08 +01:00
unistd Merge "bionic: pass MADV_MERGEABLE on private & anonymous mmaps" 2012-03-21 13:51:42 -07:00
wchar wchar.h: improve wchar_t support in Bionic 2010-06-15 07:04:41 -07:00
zoneinfo Update to tzdata2012c. 2012-04-02 07:43:15 -07:00
Android.mk New additions/bug fixes required/found when porting perf. 2012-03-20 12:54:55 -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 Clean up NOTICE files. 2010-10-19 15:12:40 -07:00
README Add an 's and a . to the bionic/libc README. 2009-07-23 17:41:47 -07:00
SYSCALLS.TXT Update kernel headers and add syscall "perf_event_open" 2012-03-13 12:28:40 -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.