LICENSE

   1 Userspace RCU library licensing
   2 Mathieu Desnoyers
   3 May 10, 2009
   4
   5
   6 * LGPLv2.1
   7
   8 The library part is distributed under LGPLv2.1 or later. See lgpl-2.1.txt for
   9 details. This applies to :
  10
  11 urcu.h
  12 urcu.c
  13 urcu-static.h
  14 arch_x86.h
  15 arch_ppc.h
  16
  17 LGPL-compatible source code can statically use the library header using :
  18
  19 #define _LGPL_SOURCE
  20 #include <urcu.h>
  21
  22 Dynamic-only linking with the LGPL library is used if _LGPL_SOURCE is not
  23 defined. It permits relinking with newer versions of the library, which is
  24 required by the LGPL license.
  25
  26
  27 * MIT-style license :
  28
  29 xchg() privimitive has been rewritten from scratch starting from atomic_ops 1.2
  30 which has a MIT-style license that is intended to allow use in both free and
  31 proprietary software:
  32         http://www.hpl.hp.com/research/linux/atomic_ops/LICENSING.txt
  33         http://www.hpl.hp.com/personal/Hans_Boehm/gc/gc_source/
  34
  35 This license applies to :
  36
  37 arch_atomic_x86.h
  38 arch_atomic_ppc.h
  39
  40
  41 * GPLv2
  42
  43 Library test code is distributed under the GPLv2 license. See gpl-2.0.txt for
  44 details. This applies to :
  45
  46 urcutorture.h
  47 urcutorture.c
  48 api_x86.h
  49 api_ppc.h
  50 test_urcu.c
  51 test_urcu_yield.c
  52 test_rwlock_timing.c
  53 urcu-asm.c
  54
  55
  56 Various details :
  57
  58 ACCESS_ONCE(), likely(), unlikely() and barrier() are considered trivial enough
  59 that copyright does not apply to them. I (Mathieu Desnoyers) re-typed them from
  60 scratch in a mail client just to prove it.