Changeset ae78b53 in mainline

Timestamp:

2008-01-19T13:40:38Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

4bb31f7

Parents:

5973fd0

Message:

Introduce the notion of lflag (i.e. lookup flags) to support the ability to
limit the scope of VFS node types that can be opened by open() and opendir(). In
the future, lflag will also specify actions for VFS_LOOKUP handlers that will be
carried out in situations such as the VFS node is not found (e.g. implementation
of mkdir() and open() with O_CREAT in oflag).

Location:

uspace

Files:

• lib/libc/generic/vfs.c (modified) (4 diffs)
• srv/fs/tmpfs/tmpfs_ops.c (modified) (1 diff)
• srv/vfs/vfs.h (modified) (2 diffs)
• srv/vfs/vfs_lookup.c (modified) (3 diffs)
• srv/vfs/vfs_ops.c (modified) (4 diffs)

uspace/lib/libc/generic/vfs.c

@@ -96 +96 @@
 }
 
-
-int open(const char *path, int oflag, ...)
+static int _open(const char *path, int lflag, int oflag, ...)
 {
         int res;
@@ -114 +113 @@
                 }
         }
-        req = async_send_2(vfs_phone, VFS_OPEN, oflag, 0, &answer);
+        req = async_send_3(vfs_phone, VFS_OPEN, lflag, oflag, 0, &answer);
         rc = ipc_data_write_start(vfs_phone, path, strlen(path));
         if (rc != EOK) {
@@ -126 +125 @@
         futex_up(&vfs_phone_futex);
         return (int) IPC_GET_ARG1(answer);
+}
+
+int open(const char *path, int oflag, ...)
+{
+        return _open(path, L_FILE, oflag);
 }
 
@@ -243 +247 @@
         if (!dirp)
                 return NULL;
-        dirp->fd = open(dirname, 0);    /* TODO: must be a directory */
+        dirp->fd = _open(dirname, L_DIRECTORY, 0);
         if (dirp->fd < 0) {
                 free(dirp);

uspace/srv/fs/tmpfs/tmpfs_ops.c

@@ -237 +237 @@
         unsigned last = IPC_GET_ARG2(*request);
         int dev_handle = IPC_GET_ARG3(*request);
+        int lflag = IPC_GET_ARG4(*request);
 
         if (last < next)

uspace/srv/vfs/vfs.h

@@ -139 +139 @@
 } vfs_triplet_t;
 
+#define L_FILE          1
+#define L_DIRECTORY     2
+
 typedef struct {
         vfs_triplet_t triplet;
@@ -204 +207 @@
 extern int fs_name_to_handle(char *, bool);
 
-extern int vfs_lookup_internal(char *, size_t, vfs_lookup_res_t *,
+extern int vfs_lookup_internal(char *, size_t, int, vfs_lookup_res_t *,
     vfs_pair_t *);
 

uspace/srv/vfs/vfs_lookup.c

@@ -56 +56 @@
  * @param path          Path to be resolved; it needn't be an ASCIIZ string.
  * @param len           Number of path characters pointed by path.
+ * @param lflag         Flags to be used during lookup.
  * @param result        Empty structure where the lookup result will be stored.
  * @param altroot       If non-empty, will be used instead of rootfs as the root
@@ -62 +63 @@
  * @return              EOK on success or an error code from errno.h.
  */
-int vfs_lookup_internal(char *path, size_t len, vfs_lookup_res_t *result,
-    vfs_pair_t *altroot)
+int vfs_lookup_internal(char *path, size_t len, int lflag,
+    vfs_lookup_res_t *result, vfs_pair_t *altroot)
 {
         vfs_pair_t *root;
@@ -145 +146 @@
         ipc_call_t answer;
         int phone = vfs_grab_phone(root->fs_handle);
-        aid_t req = async_send_3(phone, VFS_LOOKUP, (ipcarg_t) first,
+        aid_t req = async_send_4(phone, VFS_LOOKUP, (ipcarg_t) first,
             (ipcarg_t) (first + len - 1) % PLB_SIZE,
-            (ipcarg_t) root->dev_handle, &answer);
+            (ipcarg_t) root->dev_handle, (ipcarg_t) lflag, &answer);
         vfs_release_phone(phone);
 

uspace/srv/vfs/vfs_ops.c

@@ -72 +72 @@
         };
 
-        return vfs_lookup_internal("/", strlen("/"), result, &altroot);
+        return vfs_lookup_internal("/", strlen("/"), L_DIRECTORY, result,
+            &altroot);
 }
 
@@ -196 +197 @@
                  */
                 rwlock_write_lock(&namespace_rwlock);
-                rc = vfs_lookup_internal(buf, size, &mp_res, NULL);
+                rc = vfs_lookup_internal(buf, size, L_DIRECTORY, &mp_res,
+                    NULL);
                 if (rc != EOK) {
                         /*
@@ -298 +300 @@
 
         /*
-         * The POSIX interface is open(path, flags, mode).
-         * We can receive flags and mode along with the VFS_OPEN call; the path
+         * The POSIX interface is open(path, oflag, mode).
+         * We can receive oflags and mode along with the VFS_OPEN call; the path
          * will need to arrive in another call.
-         */
-        int flags = IPC_GET_ARG1(*request);
-        int mode = IPC_GET_ARG2(*request);
+         *
+         * We also receive one private, non-POSIX set of flags called lflag
+         * used to pass information to vfs_lookup_internal().
+         */
+        int lflag = IPC_GET_ARG1(*request);
+        int oflag = IPC_GET_ARG2(*request);
+        int mode = IPC_GET_ARG3(*request);
         size_t len;
 
@@ -346 +352 @@
          */
         vfs_lookup_res_t lr;
-        rc = vfs_lookup_internal(path, len, &lr, NULL);
+        rc = vfs_lookup_internal(path, len, lflag, &lr, NULL);
         if (rc) {
                 rwlock_read_unlock(&namespace_rwlock);