unposixfy calls to TSRM

Define macros only, if one of the locking _r functions is used

Fix typo (shutdown -> startup)

- move strtok_r into reentrancy.c
- add rand_r()

Add/update copyright headers

Add reentrant versions of ctime, localtime, gmtime, asctime.

These cannot be implemented platform-independent, so we fall back to the native
non-reentrant versions, but lock during each

Add reentrant versions of ctime, localtime, gmtime, asctime.

These cannot be implemented platform-independent, so we fall back to the native
non-reentrant versions, but lock during each access (only if ZTS is used).

To initialize/destroy the used data structures, you need to call
reentrancy_startup() before sapi_startup(), and reentrancy_shutdown() after
sapi_shutdown().

show more ...