WebSVN – HelenOS – Diff – /trunk/uspace/srv/vfs/vfs_ops.c

 /**
  * @file    vfs_ops.c
  * @brief   Operations that VFS offers to its clients.
  */
+#include "vfs.h"
 #include <ipc/ipc.h>
 #include <async.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <ctype.h>
 #include <fcntl.h>
 #include <assert.h>
 #include <atomic.h>
-#include "vfs.h"
+#include <vfs/canonify.h>
 /* Forward declarations of static functions. */
 static int vfs_truncate_internal(int, int, unsigned long, size_t);
 /**
     if (!ipc_data_write_receive(&callid, &len)) {
         ipc_answer_0(callid, EINVAL);
         ipc_answer_0(rid, EINVAL);
         return;
+    }
-    /*
-     * Now we are on the verge of accepting the path.
-     *
-     * There is one optimization we could do in the future: copy the path
-     * directly into the PLB using some kind of a callback.
-     */
     char *path = malloc(len + 1);
     if (!path) {
         ipc_answer_0(callid, ENOMEM);
         ipc_answer_0(rid, ENOMEM);
         return;
+    }
     int rc;
     if ((rc = ipc_data_write_finalize(callid, path, len))) {
         ipc_answer_0(rid, rc);
         free(path);
         return;
     if (!ipc_data_write_receive(&callid, &len)) {
         ipc_answer_0(callid, EINVAL);
         ipc_answer_0(rid, EINVAL);
         return;
+    }
-    /*
-     * Now we are on the verge of accepting the path.
-     *
-     * There is one optimization we could do in the future: copy the path
-     * directly into the PLB using some kind of a callback.
-     */
     char *path = malloc(len + 1);
     if (!path) {
         ipc_answer_0(callid, ENOMEM);
         ipc_answer_0(rid, ENOMEM);
         return;
+    }
     int rc;
     if ((rc = ipc_data_write_finalize(callid, path, len))) {
         ipc_answer_0(rid, rc);
         free(path);
         return;
     if (!ipc_data_write_receive(&callid, &len)) {
         ipc_answer_0(callid, EINVAL);
         ipc_answer_0(rid, EINVAL);
         return;
+    }
-    /*
-     * Now we are on the verge of accepting the path.
-     *
-     * There is one optimization we could do in the future: copy the path
-     * directly into the PLB using some kind of a callback.
-     */
     char *path = malloc(len + 1);
     if (!path) {
         ipc_answer_0(callid, ENOMEM);
         ipc_answer_0(rid, ENOMEM);
         return;
+    }
     int rc;
     if ((rc = ipc_data_write_finalize(callid, path, len))) {
         ipc_answer_0(rid, rc);
         free(path);
         return;
     path[len] = '\0';
     rwlock_write_lock(&namespace_rwlock);
     lflag &= L_DIRECTORY;   /* sanitize lflag */
     vfs_lookup_res_t lr;
-    rc = vfs_lookup_internal(path, lflag | L_DESTROY, &lr, NULL);
+    rc = vfs_lookup_internal(path, lflag | L_UNLINK, &lr, NULL);
     free(path);
     if (rc != EOK) {
         rwlock_write_unlock(&namespace_rwlock);
         ipc_answer_0(rid, rc);
         return;
     rwlock_write_unlock(&namespace_rwlock);
     vfs_node_put(node);
     ipc_answer_0(rid, EOK);
+}
+void vfs_rename(ipc_callid_t rid, ipc_call_t *request)
+{
+    size_t len;
+    ipc_callid_t callid;
+    int rc;
+    /* Retrieve the old path. */
+    if (!ipc_data_write_receive(&callid, &len)) {
+        ipc_answer_0(callid, EINVAL);
+        ipc_answer_0(rid, EINVAL);
+        return;
+    }
+    char *old = malloc(len + 1);
+    if (!old) {
+        ipc_answer_0(callid, ENOMEM);
+        ipc_answer_0(rid, ENOMEM);
+        return;
+    }
+    if ((rc = ipc_data_write_finalize(callid, old, len))) {
+        ipc_answer_0(rid, rc);
+        free(old);
+        return;
+    }
+    old[len] = '\0';
+    /* Retrieve the new path. */
+    if (!ipc_data_write_receive(&callid, &len)) {
+        ipc_answer_0(callid, EINVAL);
+        ipc_answer_0(rid, EINVAL);
+        free(old);
+        return;
+    }
+    char *new = malloc(len + 1);
+    if (!new) {
+        ipc_answer_0(callid, ENOMEM);
+        ipc_answer_0(rid, ENOMEM);
+        free(old);
+        return;
+    }
+    if ((rc = ipc_data_write_finalize(callid, new, len))) {
+        ipc_answer_0(rid, rc);
+        free(old);
+        free(new);
+        return;
+    }
+    new[len] = '\0';
+    char *oldc = canonify(old, &len);
+    char *newc = canonify(new, NULL);
+    if (!oldc || !newc) {
+        ipc_answer_0(rid, EINVAL);
+        free(old);
+        free(new);
+        return;
+    }
+    if (!strncmp(newc, oldc, len)) {
+        /* oldc is a prefix of newc */
+        ipc_answer_0(rid, EINVAL);
+        free(old);
+        free(new);
+        return;
+    }
+    vfs_lookup_res_t old_lr;
+    vfs_lookup_res_t new_lr;
+    vfs_lookup_res_t new_par_lr;
+    rwlock_write_lock(&namespace_rwlock);
+    /* Lookup the node belonging to the old file name. */
+    rc = vfs_lookup_internal(oldc, L_NONE, &old_lr, NULL);
+    if (rc != EOK) {
+        rwlock_write_unlock(&namespace_rwlock);
+        ipc_answer_0(rid, rc);
+        free(old);
+        free(new);
+        return;
+    }
+    vfs_node_t *old_node = vfs_node_get(&old_lr);
+    if (!old_node) {
+        rwlock_write_unlock(&namespace_rwlock);
+        ipc_answer_0(rid, ENOMEM);
+        free(old);
+        free(new);
+        return;
+    }
+    /* Lookup parent of the new file name. */
+    rc = vfs_lookup_internal(newc, L_PARENT, &new_par_lr, NULL);
+    if (rc != EOK) {
+        rwlock_write_unlock(&namespace_rwlock);
+        ipc_answer_0(rid, rc);
+        free(old);
+        free(new);
+        return;
+    }
+    /* Check whether linking to the same file system instance. */
+    if ((old_node->fs_handle != new_par_lr.triplet.fs_handle) ||
+        (old_node->dev_handle != new_par_lr.triplet.dev_handle)) {
+        rwlock_write_unlock(&namespace_rwlock);
+        ipc_answer_0(rid, EXDEV);   /* different file systems */
+        free(old);
+        free(new);
+        return;
+    }
+    /* Destroy the old link for the new name. */
+    vfs_node_t *new_node = NULL;
+    rc = vfs_lookup_internal(newc, L_UNLINK, &new_lr, NULL);
+    switch (rc) {
+    case ENOENT:
+        /* simply not in our way */
+        break;
+    case EOK:
+        new_node = vfs_node_get(&new_lr);
+        if (!new_node) {
+            rwlock_write_unlock(&namespace_rwlock);
+            ipc_answer_0(rid, ENOMEM);
+            free(old);
+            free(new);
+            return;
+        }
+        new_node->lnkcnt--;
+        break;
+    default:
+        rwlock_write_unlock(&namespace_rwlock);
+        ipc_answer_0(rid, ENOTEMPTY);
+        free(old);
+        free(new);
+        return;
+    }
+    /* Create the new link for the new name. */
+    rc = vfs_lookup_internal(newc, L_LINK, NULL, NULL, old_node->index);
+    if (rc != EOK) {
+        rwlock_write_unlock(&namespace_rwlock);
+        if (new_node)
+            vfs_node_put(new_node);
+        ipc_answer_0(rid, rc);
+        free(old);
+        free(new);
+        return;
+    }
+    old_node->lnkcnt++;
+    /* Destroy the link for the old name. */
+    rc = vfs_lookup_internal(oldc, L_UNLINK, NULL, NULL);
+    if (rc != EOK) {
+        rwlock_write_unlock(&namespace_rwlock);
+        vfs_node_put(old_node);
+        if (new_node)
+            vfs_node_put(new_node);
+        ipc_answer_0(rid, rc);
+        free(old);
+        free(new);
+        return;
+    }
+    old_node->lnkcnt--;
+    rwlock_write_unlock(&namespace_rwlock);
+    vfs_node_put(old_node);
+    if (new_node)
+        vfs_node_put(new_node);
+    free(old);
+    free(new);
+    ipc_answer_0(rid, EOK);
+}
 /**
  * @}
  */

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/vfs/vfs_ops.c – Rev 2752 → 2763