The NetBSD libc provides a mechanism to have versions of system calls.
By 'renaming' symbols to a new version, freshly compiled programs will
automatically use the new symbol iff they use the proper header files. The
old, not renamed, version of the symbol will still exist (after being moved
to the compat directory), so old programs can still link.
Since MINIX doesn't support dynamic linking, the whole rename mechanism
doesn't really work for us. However, removing it would create a huge diff
with the current NetBSD libc.
A lot of the compat code relies on things we don't (seem to) have, and
therefore does not get built and linked. This causes trouble for tools like
autoconf, which will fail to find the renamed symbols. For example,
currently select gets renamed to __select50 in libc. Autoconf looks for
'select' and doesn't find it and reports we don't have it. This is where
the compat.S stub comes into play: it generates the old symbols and jumps to
the new symbols. However, as this is done in one object file, all renamed
symbols get linked together, causing binaries to be huge. This patch fixes
that by generating an object file for each renamed symbol.
This patch also makes the MISSING_SYSCALLS more complete and marginally
reduces the diff with NetBSD.
This patch include various fixes to NBSD includes.
- unistd.h: Avoid different linkages on non-_NETBSD_SOURCE
compilation;
- stdlib.h: remove devname declaration.
- sys/select.h: Add _MINIX specific flags.
- limits.h: Add SYMLOOP_MAX and SYMLINK_MAX
- time.h: Fix CLOCKS_PER_SEC and remove BSD's timer_t, as it
confuses minix own specific timers.
- utmp.h: Set Minix-specific paths and use Minix utmp format.
- param.h: Do not set BSD4_4, as this mostly means sa_len in
struct sock_addr.
- arch/i386/include/param.h: include <machine/vmparam.h> to
add PAGE_SIZE and related macros, defined round_page() and
trunc_page() for minix compatibility.
- dirent.h: remove DIRBLKSIZ and fix d_ino/d_fileno.
- sys/dir.h: ADD from existing includes and edit include
conditions.
- sys/dirent.h: include <minix/dirent.h>, fix d_ino/d_fileno.
- sys/fd_set.h: set default FD_SETSIZE at __MINIX_OPENMAX, as
the default NetBSD value is too big and cause vfs to return
an error.
- sys/cdefs.h: Always include <minix/ansi.h>
- minix/paths.h: Add Minix-specific paths.
- minix/dirent.h: ADD, keep only "direct" and "flex"definitions.
- minix/types.h: include <minix/ansi.h>
- sys/Makefile: add sys/dirent.h and statfs.h (forgot!)
- minix/Makefile: add minix/dirent.h
nbsd_include/minix-port.patch updated accordingly.
This patch imports the unmodified current version of NetBSD libc.
The NetBSD includes are in /nbsd_include, while the libc code itself is
split between lib/nbsd_libc and common/lib/libc.
