3 files changed, 90 insertions, 8 deletions

diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index a2dd667..d4c9885 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -149,6 +149,7 @@ fd_rw(unsigned int fd, void *buf, size_t count, uint8_t write)
 {
     char *kbuf = NULL;
     ssize_t n;
+    uint32_t seal;
     struct filedesc *filedes;
     struct sio_txn sio;
     scret_t retval = 0;
@@ -159,8 +160,17 @@ fd_rw(unsigned int fd, void *buf, size_t count, uint8_t write)
     }
 
     filedes = fd_get(fd);
-    kbuf = dynalloc(count);
+    seal = filedes->flags;
 
+    /* Check the seal */
+    if (write && !ISSET(seal, O_ALLOW_WR)) {
+        return -EPERM;
+    }
+    if (!write && ISSET(seal, O_WRONLY)) {
+        return -EPERM;
+    }
+
+    kbuf = dynalloc(count);
     if (kbuf == NULL) {
         retval = -ENOMEM;
         goto done;
@@ -229,6 +239,29 @@ done:
     return retval;
 }
 
+static int
+fd_do_create(const char *path, struct nameidata *ndp)
+{
+    struct vop_create_args cargs;
+    struct vnode *dirvp = ndp->vp;
+    const struct vops *vops = dirvp->vops;
+    int error;
+
+    if (vops->create == NULL) {
+        return -EINVAL;
+    }
+
+    cargs.path = path;
+    cargs.ppath = ndp->path;
+    cargs.dirvp = dirvp;
+    cargs.vpp = &ndp->vp;
+    if ((error = vops->create(&cargs)) < 0) {
+        return error;
+    }
+
+    return 0;
+}
+
 int
 fd_read(unsigned int fd, void *buf, size_t count)
 {
@@ -247,18 +280,17 @@ fd_write(unsigned int fd, void *buf, size_t count)
  *
  * @pathname: Path of file to open.
  * @flags: Flags to use.
- *
- * TODO: Use of flags.
  */
 int
 fd_open(const char *pathname, int flags)
 {
     int error;
+    const struct vops *vops;
     struct filedesc *filedes;
     struct nameidata nd;
 
     nd.path = pathname;
-    nd.flags = 0;
+    nd.flags = ISSET(flags, O_CREAT) ? NAMEI_WANTPARENT : 0;
 
     if ((error = namei(&nd)) < 0) {
         return error;
@@ -269,6 +301,14 @@ fd_open(const char *pathname, int flags)
         return error;
     }
 
+    vops = nd.vp->vops;
+    if (ISSET(flags, O_CREAT) && vops->create != NULL) {
+        error = fd_do_create(pathname, &nd);
+    }
+    if (error < 0) {
+        return error;
+    }
+
     filedes->vp = nd.vp;
     filedes->flags = flags;
     return filedes->fdno;
diff --git a/sys/kern/vfs_init.c b/sys/kern/vfs_init.c
index 8c1bc74..bc7f8b0 100644
--- a/sys/kern/vfs_init.c
+++ b/sys/kern/vfs_init.c
@@ -37,7 +37,8 @@ struct vnode *g_root_vnode = NULL;
 static struct fs_info fs_list[] = {
     {MOUNT_RAMFS, &g_initramfs_vfsops, 0, 0},
     {MOUNT_DEVFS, &g_devfs_vfsops, 0, 0},
-    {MOUNT_CTLFS, &g_ctlfs_vfsops, 0, 0}
+    {MOUNT_CTLFS, &g_ctlfs_vfsops, 0, 0},
+    {MOUNT_TMPFS, &g_tmpfs_vfsops, 0, 0}
 };
 
 void
diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c
index d04b812..d88c447 100644
--- a/sys/kern/vfs_lookup.c
+++ b/sys/kern/vfs_lookup.c
@@ -29,6 +29,7 @@
 
 #include <sys/namei.h>
 #include <sys/vnode.h>
+#include <sys/param.h>
 #include <sys/mount.h>
 #include <sys/errno.h>
 #include <vm/dynalloc.h>
@@ -118,20 +119,60 @@ vfs_get_fname_at(const char *path, size_t idx)
 }
 
 /*
+ * Count the number of components that exist within
+ * a path minus the delimiter as well as any redundant
+ * delimiters.
+ *
+ * @path: Path to count
+ */
+static uint8_t
+namei_num_cnp(const char *path)
+{
+    const char *p = path;
+    uint8_t count = 0;
+
+    while (*p != '\0') {
+        /* Skip redundant delimiters */
+        if (p[0] == '/' && p[1] == '/') {
+            ++p;
+            continue;
+        }
+
+        if (*p == '/') {
+            ++count;
+        }
+        ++p;
+    }
+
+    /* Don't count leading slash */
+    if (*(p - 1) == '/') {
+        --count;
+    }
+
+    return count;
+}
+
+/*
  * Search for a path within a mountpoint.
  *
  * @mp: Mountpoint to search in.
  * @path: Path to search for.
+ * @ndp: Namei data pointer
  */
 static struct vnode *
-namei_mp_search(struct mount *mp, const char *path)
+namei_mp_search(struct mount *mp, const char *path, struct nameidata *ndp)
 {
     struct vop_lookup_args lookup_args;
     struct vnode *vp = mp->vp;
+    uint8_t n_cnp = 0;
     char *name;
     int status;
 
-    for (size_t i = 1;; ++i) {
+    n_cnp = namei_num_cnp(path);
+    if (ISSET(ndp->flags, NAMEI_WANTPARENT)) {
+        --n_cnp;
+    }
+    for (size_t i = 1; i < n_cnp; ++i) {
         name = vfs_get_fname_at(path, i);
         if (name == NULL)
             break;
@@ -212,7 +253,7 @@ namei(struct nameidata *ndp)
 
         /* If the name matches, search within */
         if (strcmp(mp->name, name) == 0)
-            vp = namei_mp_search(mp, path);
+            vp = namei_mp_search(mp, path, ndp);
 
         /* Did we find it at this mountpoint? */
         if (vp != NULL) {