I'm very grateful to Charles Forsyth for creating most of Jehanne's kernel
and to 9front's guys for all the code and ideas they freely share.
Here I make their copyrights explicit as they had been erroneusly omitted
or messed up before. Sorry.
The new header envvars.h contains the names of commonly used
environment variables, such as $user, $ifs, $path and so on.
These defines are useful for Jehanne core applications that
use them to comunicate some values.
They are not strictly required, but having such defines we
can easily change the naming convention (from lowercase to uppercase).
I do not expect chown, fchownat and lchown to be much used in
UNIX softwares that we care to port.
We stub the functions in libposix so that we can refer them from
standard C libaries (such as newlib).
We will implement them (parsing /cfg/users to determinate uid and gid)
when it will be actually needed from a software ported to Jehanne.
This large commit address several issues
- removed 386 directory: Jehanne is 64bit only
- simplified kernel options management
- rewritten boot process
- ported memory related stuff from 9front's 9/pc64
- removed devacpi
- removed old code
- deep refactor of awake syscall
- removed MCACHE support for mount
- fix libc's setjmp/longjmp
With this commit all functions declared in libc.h have been renamed
with the "jehanne_" prefix. This is done for several reason:
- it removes conflicts during symbol resolution when linking
standard C libraries like newlib or musl
- it allows programs depending on a standard C library to directly
link to a library depending on our non standard libc (eg libsec).
To ease transiction two files are provided:
- sys/include/lib9.h that can be included instead of <libc.h> to use
the old names (via a simple set of macros)
- sys/src/lib/c/lib9.c that can be compiled with a program where the
macro provided by lib9.h are too dumb (see for example rc or grep).
In the kernel port/lib.h has been modified accordingly and some of
the functions it directly provides has been renamed too (eg malloc
in qmalloc.c and print in devcons.c).
These new implementations
- do several validity check on input parameters
- allow a bit larger variable names (127 bytes, aka sizeof(Proc.genbuf)-1)
- preserve nulls in the content (the original version used to replace
'\0' with ' '). I can't see why they did, actually.
See also http://marc.info/?l=9fans&m=148475801229908&w=2
Should also fix CID 155718
In Plan9 the create syscall fallback on a open(OTRUNC) if the
path provided already exists. This is actually a common requirement
as most programs (editors, cat...) simply requires that a file is
there and is empty, and doesn't care overwriting existing contents
(note that this is particularily sensible with something like fossil).
In Jehanne the application is responsible of actually handle this
"file exists" error but libc provides ocreate() to mimic the Plan9
behaviour. Note that ocreate introduce a subtle race too: the path
is walked several times if the file exists, thus it could misbehave
on concurrent namespace changes. However I guess this is not going to
happen often enough to care now.
NOTE we will probably address this rare race too, with a more drammatic change
to syscalls: a new walk() syscall that will provide an unopen fd.
Giacomo Tesio