Files
jehanne/qa/lib/c/asmscall.c
Giacomo Tesio 99855d60d6 kernel: move chdir to libc using devself/devproc
Added wdir to devself and devproc:

- read '#0/wdir' to get the working directory of the calling process
  NOTE that a read(fd, nil, -1) will return the negated length
  of the working directory, just in case you want to
  allocate the memory required

- read '/proc/n/wdir' to know the working directory of process n
  (read(fd, nil, -1) still returns the negated length)

- write '#0/wdir' to change the working directory of the calling process
  NOTE: no offset is allowed and the provided string must
  be null terminated

- write '/proc/n/wdir' to change the working directory of process n
  NOTE: no offset is allowed and the provided string must
  be null terminated; moreover if another process change the working
  directory change during the write, the current process will
  receive an error.

In libc updated getwd() and chdir().
Also modified pwd to get advantage of the new file.

To test, run /arch/amd64/qa/kern/wdir.rc or simply try

	% pwd
	/usr/glenda
	% echo -n /tmp > /proc/$pid/wdir
        % pwd
        /tmp
        % cat '#0/wdir' && echo
        /tmp

The expected use cases for wdir in devproc are rio and acme.

Also, note that we could theoretically remove the cd builtin
from rc and simply implement it as a rc function.
We don't do that to preserve rc portability to other OS.
2016-12-15 22:42:01 +01:00

53 lines
1.2 KiB
C

/*
* This file is part of Jehanne.
*
* Copyright (C) 2016 Giacomo Tesio <giacomo@tesio.it>
*
* Jehanne is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2 of the License.
*
* Jehanne is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Jehanne. If not, see <http://www.gnu.org/licenses/>.
*/
#include <u.h>
#include <libc.h>
int verbose = 1;
void
main(void)
{
int ret = 0; // success
uint64_t start, end;
char *msg;
start = sys_nsec();
sleep(1);
end = sys_nsec();
if (end <= start)
ret = 1;
if (verbose)
print("nsec: start %llx, end %llx\n", start, end);
if(ret){
msg = smprint("nsec: FAIL: start %llx end %llx",
start, end);
print("%s\n", msg);
exits(msg);
}
int fd;
fd = open("#|", ORDWR);
sys_mount(fd, -1, "/tmp", MREPL, "", 'M');
print("PASS\n");
exits("PASS");
}