minix/lib/libminlib/checkperms.c
2013-11-13 23:16:31 +00:00

28 lines
588 B
C

#include <lib.h>
#include <unistd.h>
#include <string.h>
#include <minix/safecopies.h>
int
checkperms(endpoint_t endpt, char *path, size_t size)
{
cp_grant_id_t grant;
message m;
int r;
if ((grant = cpf_grant_direct(VFS_PROC_NR, (vir_bytes) path, size,
CPF_READ | CPF_WRITE)) == GRANT_INVALID)
return -1; /* called function sets errno */
memset(&m, 0, sizeof(m));
m.VFS_CHECKPERMS_ENDPT = endpt;
m.VFS_CHECKPERMS_GRANT = grant;
m.VFS_CHECKPERMS_COUNT = size;
r = _syscall(VFS_PROC_NR, VFS_CHECKPERMS, &m);
cpf_revoke(grant); /* does not touch errno */
return r;
}