val_t eic_fcntl(void)
{
val_t v;
if(getargc() == 3) {
v.ival = fcntl(arg(0,getargs(),int),
arg(1,getargs(),int),
arg(2,getargs(),int));
} else
int builtin_cd(\
char **arg_v)
{
int arg_c;
int o;
char e;
char nwd_path[FT_SH_CWD_PATH_SIZE + 1];
e = 0;
arg_c = getargc(arg_v);
o = get_opt(CSET_CD_O, arg_c, arg_v, &e);
if (IS(O_PRIVATE_ERROR, o) || (IS(O_CD_FOLLOW, o) && IS(O_CD_NOFOLLOW, o)))
return (cd_usage(e));
arg_v += go_over_opt(arg_c, arg_v);
e = handle_cwd(arg_v, nwd_path);
if (!nwd_path[0] || e < 0)
return (1);
return ((IS(O_CD_FOLLOW, o) ? fcdenv(nwd_path, e) : cdenv(nwd_path, e)));
}
int
sys_execv(const char *progname, char**args) {
kprintf("hello world");
struct vnode *v;
vaddr_t entrypoint, stackptr;
int result;
int argc = getargc(args);
/* Copy the arguments into the kernel buffer */
char** kbuffer = kmalloc(argc*sizeof(char*));
int i;
for (i=0; i<argc; i++) {
kbuffer[i] = kmalloc(strlen(args[i])*sizeof(char*)+1);
copyinstr(args[i], kbuffer[i], strlen(args[i])*sizeof(char*)+1, NULL);
}
args = kbuffer;
/* Open the file. */
result = vfs_open(progname, O_RDONLY, &v);
if (result) {
return result;
}
/* This is not the first process, we have to make sure
the previous process address space is not NULL. */
assert(curthread->t_vmspace != NULL);
/* Destroy the old process address space */
as_destroy(curthread->t_vmspace);
/* Create a new address space. */
curthread->t_vmspace = as_create();
if (curthread->t_vmspace == NULL) {
vfs_close(v);
return ENOMEM;
}
/* Activate it. */
as_activate(curthread->t_vmspace);
/* Load the executable. */
result = load_elf(v, &entrypoint);
if (result) {
/* thread_exit destroys curthread->t_vmspace */
vfs_close(v);
return result;
}
/* Done with the file now. */
vfs_close(v);
/* Free the current process user stack */
kfree(curthread->t_stack);
/* Define the user stack in the address space */
result = as_define_stack(curthread->t_vmspace, &stackptr);
if (result) {
/* thread_exit destroys curthread->t_vmspace */
return result;
}
/* copy arguments to user space */
char **args_u; /* user space arguments.(array of ptrs
to string arguments.*/
/* string length of the arguments */
size_t argstrlen = getlen(argc, args);
/* address space for the string arguments value. */
char* arg_str = (char *) stackptr - argstrlen;
/* address space for the pointers to string arguments. */
args_u = (char **) arg_str - (argc + 1) * sizeof (char**);
/* adjust the address so that its divisable by 4 */
args_u = (int) args_u - (int) args_u % 4;
/* copy the arguments to the user address space */
int len;
for (i = 0; i < argc; i++) {
/* copy a single argument to the user address space */
copyoutstr(args[i], (userptr_t) arg_str, strlen(args[i]) + 1, &len);
/* set the user argument to the current argument string pointer */
args_u[i] = arg_str;
/* increment the argument pointer to the next argument */
arg_str += (strlen(args[i]) + 1) * sizeof (char);
}
/* set the n+1th argument to be NULL */
args_u[argc] = NULL;
/* set the stackptr to the starting point of args_u and adjust the stack pointer */
stackptr = args_u - sizeof (char**) - ((int)args_u%8);
/* Warp to user mode. */
md_usermode(argc, (userptr_t) args_u, stackptr, entrypoint);
/*********************** end of A2 stuff *****************/
/* md_usermode does not return */
panic("md_usermode returned\n");
return EINVAL;
}
