/*
* Find the vnode associated with the path, and call the stat() vnode operation.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* A component of path does not exist.
* o ENOTDIR
* A component of the path prefix of path is not a directory.
* o ENAMETOOLONG
* A component of path was too long.
*/
int
do_stat(const char *path, struct stat *buf)
{
vnode_t *tmp= NULL;
int ret;
if(buf == NULL || path==NULL)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -EINVAL;
}
if(strlen(path)>MAXPATHLEN)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -ENAMETOOLONG;
}
if ((ret = open_namev(path, NULL, &tmp, NULL)) < 0)
{
dbg(DBG_PRINT,"(GRADING2B)\n");
return ret;
}
ret = tmp->vn_ops->stat(tmp, buf);
KASSERT(tmp->vn_ops->stat);
dbg(DBG_PRINT, "(GRADING2A 3.f)\n");
vput(tmp);
return ret;
}
/*
* Find the vnode associated with the path, and call the stat() vnode operation.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* A component of path does not exist.
* o ENOTDIR
* A component of the path prefix of path is not a directory.
* o ENAMETOOLONG
* A component of path was too long.
*/
int
do_stat(const char *path, struct stat *buf)
{
/* NOT_YET_IMPLEMENTED("VFS: do_stat"); */
if (path == NULL) {
return -EINVAL;
}
vnode_t *result;
int ret;
ret = open_namev(path, 0, &result, NULL);
if (ret){
return ret;
}
/* Corrected for kernel 3 */
/* vput(result); */
/* grading guideline required */
KASSERT(result->vn_ops->stat);
dbg(DBG_PRINT,"(GRADING2A 3.f) The corresponding vnode has stat function. \n");
/* Corrected for kernel 3 */
int retVal = result->vn_ops->stat(result, buf);
vput(result);
return retVal;
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int
do_chdir(const char *path)
{
int ret;
vnode_t *tmp;
if(path == NULL || strlen(path)<1)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -EINVAL;
}
if(strlen(path)>MAXPATHLEN) return -ENAMETOOLONG;
if ((ret=open_namev(path, 0, &tmp, NULL))<0)
{
dbg(DBG_PRINT,"(GRADING2B)\n");
return ret;
}
if (!S_ISDIR(tmp->vn_mode))
{
dbg(DBG_PRINT,"(GRADING2B)\n");
vput(tmp);
return -ENOTDIR;
}
vput(curproc->p_cwd);
curproc->p_cwd = tmp;
return 0;
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
* o EISDIR
* from is a directory.
*/
int
do_link(const char *from, const char *to)
{
/*NOT_YET_IMPLEMENTED("VFS: do_link");
return 0;*/
if ((strlen(from) > MAXPATHLEN) || (strlen(to) > MAXPATHLEN)){
return -ENAMETOOLONG;
}
vnode_t *from_vnode,*to_vnode,*to_vnodeFile;
int from_retVal,to_retVal;
size_t namelen;
const char *name;
from_retVal = open_namev(from,0,&from_vnode,NULL);
if (from_retVal){
return from_retVal;
}
if (S_ISDIR(from_vnode->vn_mode)){
vput(from_vnode);
return -EISDIR;
}
to_retVal = dir_namev(to,&namelen,&name,NULL,&to_vnode);
if (to_retVal){
vput(from_vnode);
return to_retVal;
}
if (!S_ISDIR(to_vnode->vn_mode)){
vput(from_vnode);
vput(to_vnode);
return -ENOTDIR;
}
to_retVal = lookup(to_vnode,name,namelen,&to_vnodeFile);
if (!to_retVal){
vput(from_vnode);
vput(to_vnode);
vput(to_vnodeFile);
return -EEXIST;
}
else {
if (to_retVal == -ENOENT){
vput(from_vnode);
vput(to_vnode);
return from_vnode->vn_ops->link(from_vnode,to_vnode,name,namelen);
}
}
vput(from_vnode);
vput(to_vnode);
return to_retVal;
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
*/
int
do_link(const char *from, const char *to)
{
int err,err2,err3,ent;
vnode_t *res_vnode,base,*res_vnode2,base2,*result;
size_t len;
const char *name;
if(strlen(from)>NAME_LEN || strlen(to)>NAME_LEN)
{
dbg(DBG_PRINT,"(GRADING2C) (vfs_syscall.c) (do_link) Path greater than MAXPATHLEN, return -ENAMETOOLONG\n");
return -ENAMETOOLONG;
}
err=open_namev(from,0,&res_vnode,NULL);
if(err<0)
{
/*vput(res_vnode);*/
dbg(DBG_PRINT,"(GRADING2C 1.j) (vfs_syscall.c) (do_link) error returned from open_namev so cannot open to link, return error \n");
return err;
}
if(S_ISDIR(res_vnode->vn_mode))
{
vput(res_vnode);
dbg(DBG_PRINT,"(GRADING2C 1.h) (vfs_syscall.c) (do_link) Link already exists, return -EEXIST \n");
return -EISDIR;
}
err2=dir_namev(to,&len,&name,NULL,&res_vnode2);
if(err2<0)
{
vput(res_vnode);
dbg(DBG_PRINT,"(GRADING2C) (vfs_syscall.c) (do_link) error returned from dir_namev so cannot open to link, return error \n");
return err2;
}
ent=lookup(res_vnode2,name,len,&result);
if(ent==0)
{
vput(res_vnode);
dbg(DBG_PRINT,"(GRADING2C 1.i) (vfs_syscall.c) (do_link) file of new Link already exists, return -EEXIST and dec ref count \n");
vput(res_vnode2);
vput(res_vnode);
return -EEXIST;
}
/*vput(res_vnode2);*/
err3=res_vnode2->vn_ops->link(res_vnode,res_vnode2,name,len);
dbg(DBG_PRINT,"(GRADING2C 1.h) (vfs_syscall.c) (do_link) Link created\n");
vput(res_vnode2);
vput(res_vnode);
return err3;
/* NOT_YET_IMPLEMENTED("VFS: do_link");
return -1;*/
}
int
do_chdir(const char *path)
{
/* NOT_YET_IMPLEMENTED("VFS: do_chdir"); */
/*GS: path should point to something */
KASSERT(path);
dbg(DBG_PRINT, "(GRADING2C) (vfs_syscall.c) (do_chdir)\n");
/*GS: Check if a path too long. */
if(strlen(path) > MAXPATHLEN)
{
dbg(DBG_PRINT, "(GRADING2C 1.n) (vfs_syscall.c) (do_chdir) path too long, return -ENAMETOOLONG\n");
return -ENAMETOOLONG;
}
/*GS: This returns in newcwd the vnode requested by the other parameters.
* and ups the refcount to the new cwd*/
vnode_t *newcwd = NULL;
int retVal = open_namev(path, O_RDONLY, &newcwd, curproc->p_cwd);
/* GS: NOTE! - need to confirm open_namev error values after implemented */
if( retVal < 0 )
{
dbg(DBG_PRINT, "(GRADING2B) (vfs_syscall.c) (do_chdir) error open_namev, cannot open, return error\n");
return retVal;
}
/*GS: check if the path does not exist.*/
/*if( newcwd == NULL )
{
dbg(DBG_PRINT, "(GRADING2C) (vfs_syscall.c) (do_chdir) path does not exist, return -ENOENT\n");
return -ENOENT;
}*/
/*GS: Check if a component of path is not a directory.*/
if (!S_ISDIR(newcwd->vn_mode))
{
/*GS: need to down the count back*/
vput(newcwd);
dbg(DBG_PRINT, "(GRADING2B) component of path is not a directory, return -ENOTDIR\n");
return -ENOTDIR;
}
/*GS: Down the refcount to the old cwd - vput() */
vput(curproc->p_cwd);
/*GS: Make the named directory the current process's cwd */
curproc->p_cwd = newcwd;
vref(curproc->p_cwd);
vput(newcwd);
return 0;
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
* o EISDIR
* from is a directory.
*/
int do_link(const char *from, const char *to) {
/*NOT_YET_IMPLEMENTED("VFS: do_link");*/
vnode_t *from_vn, *to_result;
size_t to_namelen;
const char *to_name;
vnode_t *to_vn;
int to_retdir_namev, to_retlookup;
open_namev(from, O_RDONLY, &from_vn, NULL);
dbg(DBG_PRINT, "(GRADING3D 2)\n");
/*if (ret_namev < 0) {
dbg(DBG_ERROR, "2\n");
return ret_namev;
}*/
if (S_ISDIR((from_vn)->vn_mode)) {
dbg(DBG_PRINT, "(GRADING3D 2)\n");
vput(from_vn);
return -EISDIR;
}
to_retdir_namev = dir_namev(to, &to_namelen, &to_name, NULL, &to_vn);
if (to_retdir_namev < 0) {
dbg(DBG_PRINT, "(GRADING3D 2)\n");
vput(from_vn);
return to_retdir_namev;
}
/*if (to_vn->vn_ops->link == NULL) {
dbg(DBG_ERROR, "5\n");
return -ENOTDIR;
}*/
to_retlookup = lookup(to_vn, to_name, to_namelen, &to_result);
if (to_retlookup == 0) {
dbg(DBG_PRINT, "(GRADING3D 2)\n");
vput(to_result);
return -EEXIST;
} else {
dbg(DBG_PRINT, "(GRADING3D 2)\n");
int to_retlink = to_vn->vn_ops->link(from_vn, to_vn, to_name, to_namelen);
vput(to_vn);
vput(from_vn);
return to_retlink;
}
return -1;
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
* o EISDIR
* from is a directory.
*/
int
do_link(const char *from, const char *to)
{
/*NOT_YET_IMPLEMENTED("VFS: do_link");
return -1;*/
const char *name;
size_t name_len;
int ret;
vnode_t *from_vnode,*to_p_vnode,*to_vnode;
if(from == NULL || to == NULL)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -EINVAL;
}
if(strlen(from)>MAXPATHLEN || strlen(to)>MAXPATHLEN)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -ENAMETOOLONG;
}
if ((ret = open_namev(from,NULL,&from_vnode,NULL))<0)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return ret;
}
vput(from_vnode);
if ((ret = dir_namev(to,&name_len,&name,NULL,&to_p_vnode))<0)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return ret;
}
vput(to_p_vnode);
if (S_ISDIR(from_vnode->vn_mode))
{
dbg(DBG_PRINT,"(GRADING2D)\n");
return -EISDIR;
}
if ((ret = lookup(to_p_vnode,name,name_len,&to_vnode) )== 0)
{
dbg(DBG_PRINT,"(GRADING2D)\n");
vput(to_vnode);
return -EEXIST;
}
return to_p_vnode->vn_ops->link(from_vnode,to_p_vnode,name,name_len);
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int do_chdir(const char *path) {
/* NOT_YET_IMPLEMENTED("VFS: do_chdir"); */
int retopen_namev=0;
vnode_t *result;
dbg(DBG_PRINT, "(GRADING2B)\n");
/*int retdir_namev;*/
/*if (strlen(path) > MAXPATHLEN){
dbg(DBG_ERROR, "1\n");
return -ENAMETOOLONG;
}*/
/*retdir_namev =*/
/*if (strlen(name) > NAME_LEN) {
dbg(DBG_ERROR, "2\n");
if (retdir_namev == 0) {
dbg(DBG_ERROR, "3\n");
vput(res_vnode);
}
return -ENAMETOOLONG;
}
if (retdir_namev != 0) {
dbg(DBG_ERROR, "4\n");
dbg(DBG_PRINT, "1chdir returns %d\n", retdir_namev);
return retdir_namev;
}*/
retopen_namev = open_namev(path, O_RDONLY, &result, NULL);
if (retopen_namev < 0) {
return retopen_namev;
}
if (!S_ISDIR(result->vn_mode)) {
dbg(DBG_PRINT, "(GRADING2B)\n");
vput(result);
return -ENOTDIR;
}
vput(curproc->p_cwd);
curproc->p_cwd = result;
dbg(DBG_PRINT, "(GRADING2B)\n");
return 0;
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int
do_chdir(const char *path)
{
if(strlen(path) > MAXPATHLEN)
{
dbg(DBG_PRINT,"(GRADING2B) one of the component in the path field is too long\n");
dbg(DBG_PRINT,"do_chdir(): one of the component in the path field is too long\n");
return -ENAMETOOLONG;
}
if(strlen(path) <= 0)
{
dbg(DBG_PRINT,"(GRADING2B) Invalid path name\n");
dbg(DBG_PRINT,"do_chdir(): Invalid path name\n");
return -EINVAL;
}
size_t namelen;
char *name;
vnode_t *res_vnode;
int ret_val =0;
ret_val = open_namev(path,0,&res_vnode,NULL);
if(ret_val<0)
{
dbg(DBG_PRINT,"(GRADING2B) Error while accessing open_namev\n");
return ret_val;
}
if(!S_ISDIR(res_vnode->vn_mode))
{
vput(res_vnode);
dbg(DBG_PRINT,"(GRADING2B) Given path is not a directory\n");
return -ENOTDIR;
}
vput(curproc->p_cwd);
curproc->p_cwd = res_vnode;
return 0;
/*NOT_YET_IMPLEMENTED("VFS: do_chdir");
return -1;*/
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int
do_chdir(const char *path)
{
size_t namelen=0;
const char *name=NULL;
vnode_t *base = NULL;
vnode_t *res_vnode=NULL;
KASSERT(path);
int namev_ret = open_namev(path, 0, &res_vnode, NULL);
if(namev_ret<0)
{
KASSERT(namev_ret<0);
dbg(DBG_PRINT,"(GRADING2D 3.f): Path component has failed.\n");
return namev_ret;
}
if(!S_ISDIR(res_vnode->vn_mode))
{
KASSERT(!S_ISDIR(res_vnode->vn_mode));
dbg(DBG_PRINT, "(GRADING2D 3.b): The path is not to a directory.\n");
vput(res_vnode);
return -ENOTDIR;
}
KASSERT(res_vnode != NULL);
/* Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()).*/
KASSERT(curproc != NULL);
vput(curproc->p_cwd);
curproc->p_cwd=res_vnode;
/* Might need to increase the ref_count, but I think it should instead
* happen inside lookup which gets called by open_namev.*/
/*vget(res_vnode->vn_fs,res_vnode->vn_vno);*/
dbg(DBG_PRINT, "(GRADING2D 3.i): Successfully changed directory.\n");
return 0;
}
int
do_stat(const char *path, struct stat *buf)
{
/* NOT_YET_IMPLEMENTED("VFS: do_stat");*/
/*GS: path should point to something */
KASSERT(path);
/*GS: buf should point to something */
KASSERT(buf);
int retVal = 0;
/*GS: check if strlen too long*/
if( strlen(path) > MAXPATHLEN )
{
dbg(DBG_PRINT, "(GRADING2C 1.l) (vfs_syscall.c) (do_stat) strlen too long, return -ENAMETOOLONG\n");
return -ENAMETOOLONG;
}
vnode_t *vnode;
/*GS: return the vnode of the associated path */
retVal = open_namev(path, O_RDONLY, &vnode, NULL);
if(retVal < 0) /*GS: NOTE! need to check what the return values are once implemented*/
{
/*GS: ENOTDIR and ENOENT should both get caught here*/
dbg(DBG_PRINT, "(GRADING2B) (vfs_syscall.c) (do_stat) ENOTDIR or ENOENT\n");
return retVal;
}
/*GS: stat() should point to something */
KASSERT(NULL != vnode->vn_ops->stat);
dbg(DBG_PRINT,"(GRADING2A 3.f) (middle) KASSERT(vnode->->vn_ops->stat)\n");
/*GS: call the stat() vnode operation*/
retVal = vnode->vn_ops->stat(vnode, buf);
vput(vnode);
return retVal;
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int
do_chdir(const char *path)
{
/*NOT_YET_IMPLEMENTED("VFS: do_chdir");
return -1;
*/
/*dbg(DBG_PRINT,"Entering do_chdir ****************************************\n");
*/
int retvar;
/* size_t namelen;
const char *name;
vnode_t *res_vnode;
retvar = dir_namev(path,&namelen,&name,NULL,&res_vnode);
*/
/*dbg(DBG_PRINT,"(GRADING2C V41)\n");
*/
vnode_t *res_vnode;
retvar = open_namev(path,000,&res_vnode,NULL);
if (retvar < 0)
{
/*vput(res_vnode);
*/
dbg(DBG_PRINT,"(GRADING2C)\n");
/*dbg(DBG_PRINT,"retvar %d Leaving do_chdir ****************************************\n",retvar);
*/
return retvar;
}
if(!S_ISDIR(res_vnode->vn_mode))
{
vput(res_vnode);
dbg(DBG_PRINT,"(GRADING2C)\n");
return -ENOTDIR;
}
vput(curproc->p_cwd);
curproc->p_cwd = res_vnode;
dbg(DBG_PRINT,"(GRADING2C)\n");
/*dbg(DBG_PRINT,"Leaving do_chdir ****************************************\n");
*/
return 0;
}
/*
* Find the vnode associated with the path, and call the stat() vnode operation.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* A component of path does not exist.
* o ENOTDIR
* A component of the path prefix of path is not a directory.
* o ENAMETOOLONG
* A component of path was too long.
*/
int do_stat(const char *path, struct stat *buf) {
/* NOT_YET_IMPLEMENTED("VFS: do_stat"); */
vnode_t *result;
int retopen_namev=0;
/*size_t *namelen = (size_t) kalloc(sizeof(size_t));
const char **name = (char) kalloc(sizeof(char));
vnode_t **res_vnode = (vnode_t) kalloc(sizeof(vnode_t)); */
/*if (strlen(path) > MAXPATHLEN) {
dbg(DBG_ERROR, "2\n");
return ENAMETOOLONG;
}*/
/* Base passed NULL since dir_nameve can handle acccordingly */
/*if (retdir_namev != 0) {
dbg(DBG_ERROR, "3\n");
return retdir_namev;
}
if (strlen(name) > NAME_LEN) {
dbg(DBG_ERROR, "4\n");
vput(res_vnode);
return -ENAMETOOLONG;
}*/
if (path == NULL || buf == NULL || strlen(path) == 0) {
dbg(DBG_PRINT, "(GRADING2B)\n");
return -EINVAL;
}
retopen_namev = open_namev(path, O_RDONLY, &result, NULL);
if (retopen_namev < 0) {
dbg(DBG_PRINT, "(GRADING2B)\n");
return retopen_namev;
}
retopen_namev = result->vn_ops->stat(result, buf);
vput(result);
return retopen_namev;
}
/* Make the named directory the current process's cwd (current working
* directory). Don't forget to down the refcount to the old cwd (vput()) and
* up the refcount to the new cwd (open_namev() or vget()). Return 0 on
* success.
*
* Error cases you must handle for this function at the VFS level:
* o ENOENT
* path does not exist.
* o ENAMETOOLONG
* A component of path was too long.
* o ENOTDIR
* A component of path is not a directory.
*/
int
do_chdir(const char *path)
{
/* NOT_YET_IMPLEMENTED("VFS: do_chdir"); */
int ret = 0;
int flag = 0; /* Should this be 0 */
vnode_t *dir;
vnode_t *temp = curproc->p_cwd;
ret = open_namev(path, flag, &dir, NULL);
if (ret == -ENOENT){
return -ENOENT;
}
if (ret == -ENOTDIR){
return -ENOTDIR;
}
/* ERROR!!! A component of filename was too long.*/
if (ret == -ENAMETOOLONG){
return -ENAMETOOLONG;
}
if (ret) {
return ret;
}
if (dir->vn_mode != S_IFDIR) {
vput(dir);
return -ENOTDIR;
}
/*Since the change_dir has been successful, vput the old cwd.*/
vput(temp);
curproc->p_cwd = dir;
return 0;
}
int
do_open(const char *filename, int oflags)
{
/*NOT_YET_IMPLEMENTED("VFS: do_open");*/
if (oflags!=O_RDONLY && oflags!=O_WRONLY && oflags!=O_RDWR && oflags!=O_APPEND && oflags!= (O_RDONLY | O_CREAT)
&& oflags != (O_RDWR | O_CREAT) && oflags != (O_RDWR | O_APPEND))
{
return -EINVAL;
}
int fd = get_empty_fd(curproc);
if( fd == -EMFILE){
return -EMFILE;
}
file_t *f = fget(-1);
if( f == NULL){
return -ENOMEM;
}
curproc->p_files[fd] = f;
/*Set file_t->f_mode to OR of FMODE_(READ|WRITE|APPEND) based on
* oflags, which can be O_RDONLY, O_WRONLY or O_RDWR, possibly OR'd with
* O_APPEND.
*/
/*FIXME check the logic below*/
if(oflags == O_RDONLY){
f->f_mode = FMODE_READ;
}else if(oflags == O_WRONLY){
f->f_mode = FMODE_WRITE;
}else if(oflags == O_RDWR){
f->f_mode = FMODE_READ | FMODE_WRITE;
}else if(oflags == O_APPEND){
f->f_mode = FMODE_WRITE | FMODE_APPEND;
}else if(oflags == (O_RDONLY | O_CREAT)){
f->f_mode = FMODE_READ;
}else if(oflags == (O_RDWR | O_CREAT) ){
f->f_mode = FMODE_READ | FMODE_WRITE;
}else if(oflags == (O_RDWR | O_APPEND) ){
f->f_mode = FMODE_READ | FMODE_WRITE | FMODE_APPEND;
}
vnode_t *pVnode;
int s = open_namev(filename, oflags, &pVnode, NULL);
if(s != 0){
curproc->p_files[fd] = NULL;
fput(f);
return s;
}
if(S_ISDIR(pVnode->vn_mode) && ((oflags & O_WRONLY) || (oflags & O_RDWR)) ){
curproc->p_files[fd] = NULL;
vput(pVnode);
fput(f);
return -EISDIR;
}
if(S_ISBLK(pVnode->vn_mode)){
if(!(pVnode->vn_bdev = blockdev_lookup(pVnode->vn_devid))){
curproc->p_files[fd] = NULL;
fput(f);
vput(pVnode);
return -ENXIO;
}
}
if(S_ISCHR(pVnode->vn_mode)){
if(!(pVnode->vn_cdev = bytedev_lookup(pVnode->vn_devid))){
curproc->p_files[fd] = NULL;
fput(f);
vput(pVnode);
return -ENXIO;
}
}
f->f_pos=0;
f->f_vnode = pVnode;
return fd;
}
int
do_open(const char *filename, int oflags)
{
/*NOT_YET_IMPLEMENTED("VFS: do_open");*/
/* Check validity of oflags */
int flag_write_only = oflags & O_WRONLY;
int flag_readwrite = oflags & O_RDWR;
int flag_append = oflags & O_APPEND;
int flag_create = oflags & O_CREAT;
/* oflags is Read_Only and also trying to write/append/create
if( !oflags && ( flag_write_only || flag_readwrite || flag_append || flag_create) ) {
dbg(DBG_PRINT, "Add self test dbg here (GRADING1C 7)\n");
return(-EINVAL);
}*/
/* Trying to read from write_only */
if( flag_write_only && flag_readwrite ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
return(-EINVAL);
}
int file_mode = 0;
if( oflags == 0 ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
file_mode = file_mode | FMODE_READ;
}
if( flag_write_only ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
file_mode = file_mode | FMODE_WRITE;
}
if( flag_readwrite ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
file_mode = file_mode | FMODE_READ | FMODE_WRITE;
}
if( flag_append ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
file_mode = file_mode | FMODE_APPEND;
}
vnode_t *new_vnode;
int namev_ret = open_namev(filename, oflags, &new_vnode , NULL);
if( namev_ret ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
return namev_ret;
}
int next_fd;
next_fd = get_empty_fd(curproc);
/*if ( next_fd == -EMFILE ) {
vput(new_vnode);
return -EMFILE;
}*/
curproc->p_files[next_fd] = fget(-1);
curproc->p_files[next_fd]->f_mode = file_mode;
if( S_ISDIR(new_vnode->vn_mode) && (flag_write_only || flag_readwrite) ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
fput(curproc->p_files[next_fd]);
curproc->p_files[next_fd] = NULL;
vput(new_vnode);
return(-EISDIR);
}
if( S_ISCHR(new_vnode->vn_mode) && !(new_vnode->vn_cdev) ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
fput( curproc->p_files[next_fd] );
curproc->p_files[next_fd] = NULL;
vput(new_vnode);
return(-ENXIO);
}
if( S_ISBLK(new_vnode->vn_mode) && !(new_vnode->vn_bdev) ) {
dbg(DBG_PRINT, "(GRADING2B)\n");
fput( curproc->p_files[next_fd] );
curproc->p_files[next_fd] = NULL;
vput(new_vnode);
return(-ENXIO);
}
curproc->p_files[next_fd]->f_vnode = new_vnode;
curproc->p_files[next_fd]->f_pos = 0;
return next_fd;
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
*/
int
do_link(const char *from, const char *to)
{
/* NOT_YET_IMPLEMENTED("VFS: do_link"); */
/* o open_namev(from)*/
int ret = 0;
vnode_t *from_vnode = NULL;
vnode_t *to_vnode = NULL;
size_t namelen;
const char *name;
int flag = 0; /* Not modifying the file, so flag should be 0? */
ret = open_namev(from, flag, &from_vnode, NULL);
if (ret == -ENOENT){
return -ENOENT;
}
if (ret == -ENOTDIR){
return -ENOTDIR;
}
/* ERROR!!! A component of filename was too long.*/
if (ret == -ENAMETOOLONG){
return -ENAMETOOLONG;
}
/* In case there are other errors */
if (ret) {
return ret;
}
/* Remember to vput the vnodes returned from open_namev and dir_namev.*/
/* Corrected for kernel 3 */
/* vput(from_vnode); */
/* The textbook page 30 says hard link can not be made to directory */
if (from_vnode->vn_mode == S_IFDIR) {
/* Corrected for kernel 3 */
vput(from_vnode);
return -EISDIR;
}
/* o dir_namev(to)*/
ret = dir_namev(to, &namelen, &name, NULL, &to_vnode);
if (ret == -ENOENT) {
/* Corrected for kernel 3 */
vput(from_vnode);
return -ENOENT;
}
if (ret == -ENOTDIR) {
/* Corrected for kernel 3 */
vput(from_vnode);
return -ENOTDIR;
}
/* ERROR!!! A component of filename was too long.*/
if (ret == -ENAMETOOLONG) {
/* Corrected for kernel 3 */
vput(from_vnode);
return -ENAMETOOLONG;
}
/* In case there are other errors */
if (ret) {
/* Corrected for kernel 3 */
vput(from_vnode);
return ret;
}
/* Remember to vput the vnodes returned from open_namev and dir_namev.*/
/* Corrected for kernel 3 */
/* vput(to_vnode); */
/*o EEXIST
* to already exists.
* do lookup to check if to already exists */
vnode_t *testNode;
ret = lookup(to_vnode, name, namelen, &testNode);
if (ret == 0) {
/* Corrected for kernel 3 */
vput(from_vnode);
vput(to_vnode);
vput(testNode);
return -EEXIST;
} else if (ret == -ENOTDIR) {
/* Corrected for kernel 3 */
vput(from_vnode);
vput(to_vnode);
return -ENOTDIR;
} else {
/* o call the destination dir's (to) link vn_ops.*/
ret = to_vnode->vn_ops->link(from_vnode, to_vnode, name, namelen);
/* Corrected for kernel 3 */
vput(from_vnode);
vput(to_vnode);
/* o return the result of link, or an error*/
return ret;
}
}
int
do_open(const char *filename, int oflags)
{
vnode_t *res_vnode;
int status_flag = 0, access_flag = 0, fd = 0, errno = 0;
dbg(DBG_PRINT | DBG_VFS,"Kernel2:SysMsg: begin do_open(), filename =%s\n",filename);
/*Error cases*/
if ( strlen(filename) > MAXPATHLEN )
{
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - The component of the Filename too long\n",filename);
return -ENAMETOOLONG;
}
if ( strlen(filename) < 1 )
{
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - Invalid file as length is less than 1 \n",filename);
return -EINVAL;
}
/*set up the access and status flags*/
status_flag = oflags & 0x700; /*O_CREAT,O_TRUNC,O_APPEND*/
access_flag = oflags & 0x003; /*O_RDONLY,O_WRONLY,O_RDWR*/
if ( access_flag != O_RDONLY && access_flag != O_WRONLY && access_flag != O_RDWR )
{
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - Invalid file\n",filename);
return -EINVAL;
}
/* get empty file descriptor, open file,O_CREAT handled in open_namev */
fd = get_empty_fd(curproc);
if ( fd < 0 )
{
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - Maximum number of files open\n",filename);
return -EMFILE;
}
curproc->p_files[fd] = fget(-1);
if ( curproc->p_files[fd] == NULL )
{
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - Insufficient Kernel memory\n",filename);
return -ENOMEM;
}
errno = open_namev(filename,status_flag,&res_vnode,NULL);
if ( errno < 0 )
{
fput(curproc->p_files[fd]);
return errno;
}
/* Check error for opening a dir for write*/
if ( S_ISDIR(res_vnode->vn_mode) && (access_flag == O_RDWR || access_flag == O_WRONLY))
{
fput(curproc->p_files[fd]);
vput(res_vnode);
dbg(DBG_ERROR | DBG_VFS,"Kernel2:SysMsg: in do_open(), filename =%s - The pathname is a directory or the access requested requires writing\n",filename);
return -EISDIR;
}
/* Make O_TRUNC behavior default */
if ( errno == 0 && (status_flag & O_APPEND) != O_APPEND && access_flag == O_WRONLY)
{
vput(res_vnode);
errno = do_unlink(filename);
if ( errno < 0 )
{
fput(curproc->p_files[fd]);
return errno;
}
errno = open_namev(filename,O_CREAT,&res_vnode,NULL);
if ( errno < 0 )
{
fput(curproc->p_files[fd]);
return errno;
}
}
curproc->p_files[fd]->f_vnode = res_vnode;
/*Handle file O_APPEND or O_TRUNC*/
switch ( status_flag )
{
case O_APPEND :
curproc->p_files[fd]->f_mode = FMODE_APPEND;
break;
case O_APPEND | O_CREAT :
curproc->p_files[fd]->f_mode = FMODE_APPEND;
break;
default :
curproc->p_files[fd]->f_mode = 0;
curproc->p_files[fd]->f_pos = 0;
break;
}
/*Handle file access*/
switch ( access_flag )
{
case O_RDONLY :
curproc->p_files[fd]->f_mode |= FMODE_READ;
break;
case O_WRONLY :
curproc->p_files[fd]->f_mode |= FMODE_WRITE;
break;
case O_RDWR :
curproc->p_files[fd]->f_mode |= FMODE_WRITE | FMODE_READ;
break;
}
dbg(DBG_PRINT | DBG_VFS,"Kernel2:SysMsg: begin do_open(), return fd \n");
return fd;
}
int
do_open(const char *filename, int oflags)
{
/* check invalid combinations */
int wr = oflags & O_WRONLY;
int rdwr = oflags & O_RDWR;
int rd = 0;
if( (wr == 0) && (rdwr == 0)){
rd = 1;
}
int append = oflags & O_APPEND;
int trunc = oflags &O_TRUNC;
int creat = oflags & O_CREAT;
if( (wr != 0) && (rdwr != 0) ){
return -EINVAL;
}
/* 1. Get the next empty file descriptor */
int fd = get_empty_fd(curproc);
if(fd == -EMFILE){
return -EMFILE;
}
/* 2. Call fget to get a fresh file_t */
file_t* file = fget(-1);
if(file == NULL){
/* not sure for this error */
return -ENOMEM;
}
/* 3. Save the file_t in curproc's file descriptor table */
curproc -> p_files[fd] = file;
/* 4. Set file_t->f_mode to OR of FMODE_(READ|WRITE|APPEND) based on
* oflags, which can be O_RDONLY, O_WRONLY or O_RDWR, possibly OR'd with
* O_APPEND.
*/
int mode = -1;
if( (wr != 0) ||(rd != 0) || (rdwr != 0)){
if(rd != 0){
mode = FMODE_READ;
}
else if(wr != 0){
mode = FMODE_WRITE;
}
else if(rdwr != 0){
mode = FMODE_READ | FMODE_WRITE;
}
/* last check append */
if( append != 0){
mode |= FMODE_APPEND;
}
}
if(mode == -1){
/* invalid combination */
curproc -> p_files[fd] = NULL;
fput(file);
return -EINVAL;
}
file -> f_mode = mode;
/* 5. Use open_namev() to get the vnode for the file_t. */
vnode_t* res_vnode = NULL;
vnode_t* base = curproc -> p_cwd;
int res = open_namev(filename, oflags, &res_vnode, base);
if(res < 0){
curproc -> p_files[fd] = NULL;
if(res_vnode)
vput(res_vnode);
fput(file);
return res;/* including errors: ENAMETOOLONG, ENOTDIR, ENOENT */
}
if( ((res_vnode -> vn_mode & S_IFDIR) != 0) && (mode != FMODE_READ)){
curproc -> p_files[fd] = NULL;
vput(res_vnode);
fput(file);
return -EISDIR;
}
/* 6. Fill in the fields of the file_t */
file->f_vnode = res_vnode;
file->f_pos = 0;
/* 7. return new fd */
return fd;
}
int
do_open(const char *filename, int oflags)
{
/*NOT_YET_IMPLEMENTED("VFS: do_open");*/
dbg(DBG_PRINT, "Entering do_open()....%s\n", filename);
int fd = get_empty_fd(curproc);
if(fd == -EMFILE)
{
dbg(DBG_PRINT, "Exiting do_open()....\n");
return fd;
}
if((oflags & O_RDONLY) != O_RDONLY && (oflags & O_WRONLY) != O_WRONLY && (oflags & O_RDWR) != O_RDWR)
{
dbg(DBG_PRINT,"None of the access modes(O_RDONLY, O_WRONLY, O_RDWR) set......\n");
dbg(DBG_PRINT, "Exiting do_open()....\n");
return -EINVAL;
}
if((oflags & O_RDWR) == O_RDWR && (oflags & O_WRONLY) == O_WRONLY)
{
dbg(DBG_PRINT, "Invalid flags set.........\n");
dbg(DBG_PRINT, "Exiting do_open()....\n");
return -EINVAL;
}
if((oflags & O_TRUNC) == O_TRUNC)
{
if((oflags & O_RDWR) != O_RDWR && (oflags & O_WRONLY) != O_WRONLY)
{
dbg(DBG_PRINT, "O_TRUNC set but none of the write flags are set...\n");
dbg(DBG_PRINT, "Exiting do_open()....\n");
return -EINVAL;
}
}
if((oflags & O_APPEND) == O_APPEND)
{
if((oflags & O_RDWR) != O_RDWR && (oflags & O_WRONLY) != O_WRONLY)
{
dbg(DBG_PRINT, "O_APPEND set but none of the write flags are set...........\n");
dbg(DBG_PRINT, "Exiting do_open()....\n");
return -EINVAL;
}
}
int count = 0;
/*const char *p = filename;*/
if(strlen(filename) > MAXPATHLEN) return -ENAMETOOLONG;
file_t *sft = fget(-1);
if(sft == NULL) return ENOMEM; /* not sure ..........................*/
curproc->p_files[fd] = sft;
if((oflags & O_WRONLY) == O_WRONLY)
{
sft->f_mode = FMODE_WRITE;
}
else if((oflags & O_RDWR) == O_RDWR)
{
sft->f_mode = FMODE_WRITE | FMODE_READ;
}
else
{
sft->f_mode = FMODE_READ;
}
if((oflags & O_APPEND) == O_APPEND)
{
sft->f_mode |= FMODE_APPEND;
}
vnode_t *res_vnode;
/*vfs_is_in_use(vfs_root_vn->vn_fs);*/
int openv_ret = open_namev(filename, oflags, &res_vnode, NULL);
if(openv_ret < 0)
{
/*dbg(DBG_PRINT, "do_open()\n", openv_ret);*/
fput(sft); /*Not Sure................................*/
if(openv_ret == -ENOENT && (oflags & O_CREAT) != O_CREAT)
{
dbg(DBG_PRINT, "Exiting do_open()....\n");
return -ENOENT;
}
else
{
dbg(DBG_PRINT, "Exiting do_open()....\n");
return openv_ret;
}
}
if(S_ISDIR(res_vnode->vn_mode) && ((oflags & O_WRONLY) == O_WRONLY || (oflags & O_RDWR) == O_RDWR))
{
dbg(DBG_PRINT, "Exiting from do_open()\n");
fput(sft);
vput(res_vnode);
return -EISDIR;
}
sft->f_pos = 0;
sft->f_vnode = res_vnode;
/*sft->f_refcount += 1;*/
if((oflags & O_TRUNC) == O_TRUNC)
{
sft->f_vnode->vn_len = 0;
}
if(S_ISCHR(sft->f_vnode->vn_mode))
{
if(sft->f_vnode->vn_cdev == NULL)
{
dbg(DBG_PRINT, "Exiting do_open()....\n");
/*vput(res_vnode);*/
return -ENXIO;
}
}
if(S_ISBLK(sft->f_vnode->vn_mode))
{
if(sft->f_vnode->vn_bdev == NULL)
{
dbg(DBG_PRINT, "Exiting do_open()....\n");
/*vput(res_vnode);*/
return -ENXIO;
}
}
dbg(DBG_PRINT, "Exiting do_open() normally....\n");
return fd;
}
int
do_open(const char *filename, int oflags)
{
int status;
file_t *f;
int fd = get_empty_fd(curproc);
if(fd!=EMFILE)
{
/* can fail if memory not allocated */
f = fget(-1);
if(f==NULL)
return -ENOMEM;
curproc->p_files[fd] = f;
if(oflags & O_RDONLY)
f->f_mode = FMODE_READ;
else if(oflags & O_WRONLY)
f->f_mode = FMODE_WRITE;
else if(oflags & O_RDWR)
f->f_mode = FMODE_READ | FMODE_WRITE;
else if(oflags & (O_WRONLY|O_APPEND))
f->f_mode = FMODE_WRITE|FMODE_APPEND;
else if(oflags & (O_RDWR|O_APPEND))
f->f_mode = FMODE_READ|FMODE_WRITE|FMODE_APPEND;
else
return -EINVAL; /* not sure if other combinations should be handled */
if(S_ISDIR(f->f_vnode->vn_mode) && (O_WRONLY | O_RDWR))
{
curproc->p_files[fd] = NULL;
fput(f);
return -EISDIR;
}
if( S_ISCHR(f->f_vnode->vn_mode) || S_ISBLK(f->f_vnode->vn_mode))
{
curproc->p_files[fd] = NULL;
fput(f);
return -ENXIO;
}
/* returns int */
status = open_namev(filename, oflags, (vnode_t **)(&(f->f_vnode)), NULL);
if(status<0)
{
curproc->p_files[fd] = NULL;
fput(f);
return status;
}
/* can return error codes*/
status = do_lseek(fd,0,0); /* 3rd argument SEEK_SET = 0 is not defined, not sure to do this as lseek.h not included */
if(status<0)
{
curproc->p_files[fd] = NULL;
fput(f);
return status;
}
return fd;
}
else
return -EMFILE;
/*NOT_YET_IMPLEMENTED("VFS: do_open");
return -1;*/
}
/* To link:
* o open_namev(from)
* o dir_namev(to)
* o call the destination dir's (to) link vn_ops.
* o return the result of link, or an error
*
* Remember to vput the vnodes returned from open_namev and dir_namev.
*
* Error cases you must handle for this function at the VFS level:
* o EEXIST
* to already exists.
* o ENOENT
* A directory component in from or to does not exist.
* o ENOTDIR
* A component used as a directory in from or to is not, in fact, a
* directory.
* o ENAMETOOLONG
* A component of from or to was too long.
* o EISDIR
* from is a directory.
*/
int
do_link(const char *from, const char *to)
{
if((strlen(from) > MAXPATHLEN) || (strlen(to) > MAXPATHLEN))
{
dbg(DBG_PRINT,"(GRADING2B) A component of from or to is too long\n");
dbg(DBG_ERROR, "do_link(): A component of from or to is too long\n");
return -ENAMETOOLONG;
}
if((strlen(from)) <= 0 || (strlen(to) <=0))
{
dbg(DBG_PRINT,"(GRADING2B) A component of from or to is not valid\n");
dbg(DBG_ERROR, "do_link(): A component of from or to is not valid\n");
return -EINVAL;
}
size_t namelen;
int dir_val;
int open_val;
const char *name;
int res=0;
int res_val =0;
int val=0;
vnode_t *old_vnode;
vnode_t *res_vnode; /*old_vnode (from), res_vnode(to)*/
open_val= open_namev(from,0,&old_vnode,NULL);
if(open_val < 0)
{
dbg(DBG_PRINT,"(GRADING2B) open_namev failed\n");
return open_val;
}
res_val = dir_namev(to,&namelen,&name,NULL,&res_vnode);
if(res_val < 0)
{
vput(old_vnode);
dbg(DBG_PRINT,"(GRADING2B) Error calling dir_namev\n");
dbg(DBG_ERROR, "do_link(): dir_namev failed\n");
return res_val;
}
vput(old_vnode);
if(res_vnode->vn_ops->link == NULL)
{
dbg(DBG_PRINT,"(GRADING2B) open_namev failed\n");
return -ENOTDIR;
}
else if(lookup(res_vnode,name,namelen, &res_vnode) == 0)
{
dbg(DBG_PRINT,"(GRADING2B) given path already exists\n");
vput(res_vnode);
return -EEXIST;
}
else
{
dbg(DBG_PRINT,"(GRADING2B) calling link function\n");
res = res_vnode->vn_ops->link(old_vnode,res_vnode,name,strlen(name));
vput(res_vnode);
return res;
}
/*NOT_YET_IMPLEMENTED("VFS: do_link");*/
return -1;
}
int
do_open(const char *filename, int oflags)
{
/* VFS {{{ */
int fd;
file_t *f;
vnode_t *file_vnode;
int ret;
if ((oflags & O_WRONLY) && (oflags & O_RDWR)) {
return -EINVAL;
}
if ((fd = get_empty_fd(curproc)) < 0) {
return fd;
}
if ((f = fget(-1)) == NULL) {
return -ENOMEM;
}
curproc->p_files[fd] = f;
dbg(DBG_VFS, "open on %s, file at %p\n", filename, curproc->p_files[fd]);
switch (oflags & 0x3) {
case O_RDONLY:
f->f_mode = FMODE_READ;
break;
case O_WRONLY:
f->f_mode = FMODE_WRITE;
break;
case O_RDWR:
f->f_mode = FMODE_READ | FMODE_WRITE;
break;
default:
/*kthread_cleanup_pop(1);*/
nukefd(fd);
return -EINVAL;
}
if ((ret = open_namev(filename, oflags, &file_vnode, NULL)) < 0) {
/*kthread_cleanup_pop(1);*/
nukefd(fd);
return ret;
}
if (((oflags & O_WRONLY) || (oflags & O_RDWR)) && S_ISDIR(file_vnode->vn_mode)) {
/*kthread_cleanup_pop(1);*/
nukefd(fd);
vput(file_vnode);
return -EISDIR;
}
if (S_ISBLK(file_vnode->vn_mode) && (!file_vnode->vn_bdev)) {
/*kthread_cleanup_pop(1);*/
nukefd(fd);
vput(file_vnode);
return -ENXIO;
}
if (S_ISCHR(file_vnode->vn_mode) && (!file_vnode->vn_cdev)) {
/*kthread_cleanup_pop(1);*/
nukefd(fd);
vput(file_vnode);
return -ENXIO;
}
f->f_vnode = file_vnode;
dbg(DBG_VFS, " vnode at %p\n", file_vnode);
if (oflags & O_APPEND) {
f->f_mode |= FMODE_APPEND;
}
/*kthread_cleanup_pop(0);*/
return fd;
/* VFS }}} */
return -1;
}
int
do_open(const char *filename, int oflags)
{
dbg(DBG_VFS, "calling do_open on %s\n", filename);
/* step 1: get next empty file descriptor */
int fd = get_empty_fd(curproc);
/* error case 2 */
if (fd == -EMFILE){
return -EMFILE;
}
/* step 2: Call fget to get a fresh file_t */
file_t *f = fget(-1);
/* error case 3 */
if (f == NULL){
return -ENOMEM;
}
KASSERT(f != NULL);
KASSERT(f->f_refcount == 1);
/* step 3: Save file_t in curproc's file descriptor table */
KASSERT(curproc->p_files[fd] == NULL);
curproc->p_files[fd] = f;
/* step 4: Set the file_t->f-mode */
f->f_mode = 0;
if (oflags & O_APPEND){
f->f_mode = FMODE_APPEND;
}
if ((oflags & O_WRONLY) && !(oflags & O_RDWR)){
f->f_mode |= FMODE_WRITE;
} else if ((oflags & O_RDWR) && !(oflags & O_WRONLY)){
f->f_mode |= FMODE_READ | FMODE_WRITE;
} else if (oflags == O_RDONLY || oflags == (O_RDONLY | O_CREAT)
|| oflags == (O_RDONLY | O_APPEND)
|| oflags == (O_RDONLY | O_CREAT | O_APPEND)){
f->f_mode |= FMODE_READ;
} else {
dbg(DBG_VFS, "oflags not valid\n");
fput(f);
curproc->p_files[fd] = NULL;
return -EINVAL;
}
/* make sure we have a valid mode */
KASSERT(f->f_mode == FMODE_READ
|| f->f_mode == FMODE_WRITE
|| f->f_mode == (FMODE_READ | FMODE_WRITE)
|| f->f_mode == (FMODE_WRITE | FMODE_APPEND)
|| f->f_mode == (FMODE_READ | FMODE_WRITE | FMODE_APPEND));
/* step 5: use open_namev to get the vnode for the file_t */
int open_result = open_namev(filename, oflags, &f->f_vnode, NULL);
if (open_result < 0){
curproc->p_files[fd] = NULL;
fput(f);
return open_result;
}
dbg(DBG_VFS, "found the vnode with id %d. Current refcount is %d\n",
f->f_vnode->vn_vno, f->f_vnode->vn_mmobj.mmo_refcount);
/* step 6: fill in the fields of the file_t */
/* no need to call vref, since open_namev() took care of that*/
f->f_pos = 0;
f->f_refcount = 1;
/* step 7: return new fd */
return fd;
}
