PAGESIZE is actually the version defined in POSIX base, with PAGE_SIZE
being in the XSI option. use PAGESIZE as the underlying definition to
facilitate making exposure of PAGE_SIZE conditional.
With the exception of a fenv implementation, the port is fully featured.
The port has been tested in or1ksim, the golden reference functional
simulator for OpenRISC 1000.
It passes all libc-test tests (except the math tests that
requires a fenv implementation).
The port assumes an or1k implementation that has support for
atomic instructions (l.lwa/l.swa).
Although it passes all the libc-test tests, the port is still
in an experimental state, and has yet experienced very little
'real-world' use.
PAGE_SIZE was hardcoded to 4096, which is historically what most
systems use, but on several archs it is a kernel config parameter,
user space can only know it at execution time from the aux vector.
PAGE_SIZE and PAGESIZE are not defined on archs where page size is
a runtime parameter, applications should use sysconf(_SC_PAGE_SIZE)
to query it. Internally libc code defines PAGE_SIZE to libc.page_size,
which is set to aux[AT_PAGESZ] in __init_libc and early in __dynlink
as well. (Note that libc.page_size can be accessed without GOT, ie.
before relocations are done)
Some fpathconf settings are hardcoded to 4096, these should be actually
queried from the filesystem using statfs.
based on initial work by rdp, with heavy modifications. some features
including threads are untested because qemu app-level emulation seems
to be broken and I do not have a proper system image for testing.
this is actually rather ugly, and would get even uglier if we ever
want to support further feature test macros. at some point i may
factor the bits headers into separate files for C base, POSIX base,
and nonstandard extensions (the only distinctions that seem to matter
now) and then the logic for which to include can go in the main header
rather than being duplicated for each arch. the downside of this is
that it would result in more files having to be opened during
compilation, so as long as the ugliness does not grow, i'm inclined to
leave it alone for now.
this port assumes eabi calling conventions, eabi linux syscall
convention, and presence of the kernel helpers at 0xffff0f?0 needed
for threads support. otherwise it makes very few assumptions, and the
code should work even on armv4 without thumb support, as well as on
systems with thumb interworking. the bits headers declare this a
little endian system, but as far as i can tell the code should work
equally well on big endian.
some small details are probably broken; so far, testing has been
limited to qemu/aboriginal linux.
Rich Felker
Stefan Kristiansson
Szabolcs Nagy