Add device related stubs

This patch adds a new file dev.c which contains stubs related to devices.

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Add sysexits.h

The header was taken from newlibc, release version 2.5.0.20170922.

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Implement usleep

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

patches: Fix setgroups declaration in origin

It seems that the setgroups() declaration is not POSIX. The patch fixes
that.

Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Remove functions provided by internal Unikraft libs

* User functions, such as getpwnam(), are provided by ukunistd
* pathconf() and sysconf() are provided by uksysinfo

Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

poll.h: Include lwip/sockets.h if lwIP is available

for POLLIN and friends.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Silence unused parameter warnings

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Yet another try to fix the __rtems__ shenanigans

Originally, we defined __rtems__ in sys/stat.h because we wanted it to
provide st_{a,c,m}tim in struct stat. That lead to some unintended side
effects, so we reduced the scope to only that header file by
conditional-defining-and-undefining. It turns out even that has
unintended side effects regarding the definition of sigaddset etc.

Considering that we're not really the RTEMS OS, let's try this the other
way round and provide a patch instead that unconditionally gives us
st_{a,c,m}tim, and to not touch __rtems__ definitions.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Add poll() and select() support via lwIP if available

Otherwise, provide dummy stubs.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Glue code for getpwnam()

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Align POLL* values in glue code with musl.

In turn, this helps lwip with its own definitions to not conflict with
either of these libc implementations.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

build: export -D__DYNAMIC_REENT__ to global C[XX]FLAGS if used

__DYNAMIC_REENT__ is used as a preprocessor flag in several public
header files (most importantly, stdio.h). This means that if newlib is
compiled with one set of flags and the rest of the build with another,
the header file and the implementation don't match. This leads to
problems such as stdin/stdoud/stderr not working because they always use
the (non-functional) versions inside _impure_data instead instead of the
current environment's private _reent struct.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Remove functions provided by libvfscore

The core patch 'lib/vfs: expose remaining vfs functions'
provides additional functions which are currently stubs
in newlib's gluecode. This patch removes the stubs.

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Fix fwrite's return value for newline ended strings

Fwrite does not return the correct number of items
written. If we pass a string that ends in '\n' we
get n - 1(the '\n') for a string of length n.
That is because __sputc_r returns EOF for the
the newline character. This patch solves the problem
by increasing the variable i if  __sputc_r returned
EOF when p[i] is '\n'.

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Remove readdir stub function

This is provided by vfscore, on which newlib has a dependency.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Suppress code style warnings when using GCC 6, 7 or 8

Supress code style warnings for external libnewlib sources when using
GCC 6, GCC 7, or GCC 8. The new warning suppression flags are
introduced depending on the GCC version that is in use.
Additionally, this patch name spaces `SUPPRESS_FLAGS` to
`LIBNEWLIB_SUPPRESS_FLAGS-y` and we remove the double definition of
`-Wno-implicit-function-declaration`.

Signed-off-by: Simon Kuenzer <simon.kuenzer@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Add libvfscore as dependency

The current implementation requires libvfscore to be selected. Without
libvfscore `read`, `write`, `close`, and `fstat` are undefined and
linking fails. With this commit we also fix a typo in the dependency
definition to libukalloc.

Signed-off-by: Simon Kuenzer <simon.kuenzer@neclab.eu>
Reviewed-by: Sharan Santhanam <sharan.santhanam@neclab.eu>

Remove stub for opendir

The opendir function is now provided by Unikraft's vfs library,
remove the stub from newlib to prevent multiple definition errors.

Signed-off-by: Felipe Huici <felipe.huici@neclab.eu>
Reviewed-by: Costin Lupu <costin.lupu@cs.pub.ro>

Implement gettimeofday, clock_gettime, sleep

The implementations are taken from nolibc.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Fix selectively included type definitions

The newlib glue code uses code originally taken from musl. In musl, the
way to selectively include certain data types from those defined in
types.h is through the use of __NEED_* macros. Newlib uses a different
approach: it provides all definitions as underscored variants via
sys/_types.h, and the header files then typedef them over to the normal
variants as needed, with preprocessor guards around each of them to
provent duplications.

Replace the __NEED macros (which are effectively noops, so none of those
data types ever got properly defined in those headers) with the newlib
_types solution.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Use Unikraft __getreent() when scheduling is enabled

When scheduling is enabled, Unikraft provides the __getreent() function.

The current patch also fixes the compilation warnings that occur
because of __DYNAMIC_REENT__ redefinition when __rtems__ is defined.

Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>
Reviewed-by: Florian Schmidt <florian.schmidt@neclab.eu>

Add stubs for C++ libraries

This patch adds the missing stubs needed by the
C++ llvm libraries. It creates a new locale.c
file for the stubs related to the locales.
This patch adds the missing include
to stddef inside mman.h.

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@stud.acs.upb.ro>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Fix __rtems__ usage in glue code headers

In order to use __rtems__ one has to define it in all affected headers.
Besides 'sys/stat.h', we also identified 'time.h'. Moreover, we define
__rtems__ only if it was not previously defined.

Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>

Enable setjmp and longjmp support

Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>
Reviewed-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

add declarations needed for vfscore in the gluecode

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Reviewed-by: Florian Schmidt <florian.schmidt@neclab.eu>

update newlib glue for use with vfscore

Consists of multiple fixes:
  - remove stubs of the functions provided by vfscore
  - import mount.h, statfs.h, uio.h from nolibc (minimal changes)
  - add stub for sigfillset

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Reviewed-by: Florian Schmidt <florian.schmidt@neclab.eu>

Add missing include to time.c

time.c uses errno, but doesn't include the correct header.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

Fix remaining time in nanosleep

Add the fix of commit 96f68ab in unikraft to newlib:
Calculate the remaining time to sleep and update
the rem parameter if it is given.
If the remaining time is larger than 0, it means that
the thread was waken up explicitly and nanosleep returns -1
to indicate that. Otherwise nanosleep returns 0.

Signed-off-by: Dafna Hirschfeld <dafna3@gmail.com>
Reviewed-by: Florian Schmidt <florian.schmidt@neclab.eu>

reimplement nanosleep for new api

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Signed-off-by: Simon Kuenzer <simon.kuenzer@neclab.eu>
Reviewed-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

remove functions provided by libvfscore

Which are: close, read and write

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Reviewed-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

patch: set default _READ_WRITE_RETURN_TYPE to _ssize_t

The vfscore provides the same definitions of functions read/write as
in 'man 2 write'. Newlib used int as a return type of these functions,
which is wrong.

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Reviewed-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

build: add CONFIG_ prefix to all kconfig symbols

This is needed to support similar modifications in Unikraft main repo

Signed-off-by: Yuri Volchkov <yuri.volchkov@neclab.eu>
Reviewed-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

Initial public release: documentation

This contains the initial documentation for newlib for Unikraft.

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>

Initial public release: configuration and build files

This contains the configuration and make files required to build
libnewlib for Unikraft.

Signed-off-by: Simon Kuenzer <simon.kuenzer@neclab.eu>

Initial public release: glue code

This contains the glue/wrapper code required to build libnewlib for
Unikraft.

Signed-off-by: Felipe Huici <felipe.huici@neclab.eu>
Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>

initial commit (empty)

Signed-off-by: Florian Schmidt <florian.schmidt@neclab.eu>