Changeset a8e9ab8d in mainline for uspace/srv/vfs/vfs_ops.c

Timestamp:

2008-03-09T17:18:30Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

4072980

Parents:

2664838b

Message:

Support for rename().

File:

• uspace/srv/vfs/vfs_ops.c (modified) (10 diffs)

uspace/srv/vfs/vfs_ops.c

@@ -36 +36 @@
  */
 
+#include "vfs.h"
 #include <ipc/ipc.h>
 #include <async.h>
@@ -51 +52 @@
 #include <assert.h>
 #include <atomic.h>
-#include "vfs.h"
+#include <vfs/canonify.h>
 
 /* Forward declarations of static functions. */
@@ -307 +308 @@
                 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);
@@ -321 +314 @@
                 return;
         }
-
         int rc;
         if ((rc = ipc_data_write_finalize(callid, path, len))) {
@@ -630 +622 @@
                 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);
@@ -644 +628 @@
                 return;
         }
-
         int rc;
         if ((rc = ipc_data_write_finalize(callid, path, len))) {
@@ -673 +656 @@
                 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);
@@ -687 +662 @@
                 return;
         }
-
         int rc;
         if ((rc = ipc_data_write_finalize(callid, path, len))) {
@@ -699 +673 @@
         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) {
@@ -719 +693 @@
 }
 
+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);
+}
+
 /**
  * @}