gfapi : Resolve "." and ".." only for named lookups

The patch https://review.gluster.org/#/c/17177 resolves "." and ".."
to corrosponding inodes and names before sending the request to the
backend server. But this will only work if inode and its parent is
linked properly. Incase of nameless lookup(applications like ganesha)
the inode of parent can be NULL(only gfid is send). So this patch will
resolve "." and ".." only if proper parent is available

Change-Id: I4c50258b0d896dabf000a547ab180b57df308a0b
BUG: 1460514
Signed-off-by: Jiffin Tony Thottan <jthottan@redhat.com>
Reviewed-on: https://review.gluster.org/17502
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Poornima G <pgurusid@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: soumya k <skoduri@redhat.com>
Reviewed-by: Jeff Darcy <jeff@pl.atyp.us>

1 files changed, 18 insertions, 100 deletions

diff --git a/libglusterfs/src/inode.c b/libglusterfs/src/inode.c
index 6f3bc535a14..b7b5ac6a7dd 100644
--- a/libglusterfs/src/inode.c
+++ b/libglusterfs/src/inode.c
@@ -2570,112 +2570,30 @@ out:
         return size;
 }
 
-static void
-inode_parent_null_check(inode_t **parent, inode_t *inode, char **component)
-{
-        GF_VALIDATE_OR_GOTO ("inode", inode, out);
-        GF_VALIDATE_OR_GOTO ("inode", (*component), out);
-
-        if (!(*parent) && __is_root_gfid (inode->gfid)) {
-                *parent = inode_ref (inode);
-                *component = "/";
-        }
-out:
-        return;
-}
-
-/*
- * This function changes component name and parent inode
- * if the component name is either "." or ".."
- *
- * @Paramas:
- * Parent : Parent inode of current dentry
- * component : component name that we need to test
- * dentry_name : Address for memory if need to change component.
- *               The caller has to preallocate this memory with
- *               PATH_MAX as the size.
- *
- * We return the updated parent inode and component in the
- * respective structures.
- *
- * Basic Idea of the function:
- *
- * Example 1 :
- * Path /out_dir/dir/in_dir/.
- *     In put values :
- *         parent = in_dir
- *         component : "."
- *
- *     Out put values:
- *         parent : dir
- *         component : "in_dir"
- *
- * Example 2 :
- * Path /out_dir/dir/in_dir/..
- *     In put values :
- *         parent = in_dir
- *         component : ".."
- *
- *     Out put values:
- *         parent : output_dir
- *         component : "dir"
- */
+/* *
+ * This function finds name of the inode, if it has dentry. The dentry will be
+ * created only if inode_link happens with valid parent and name. And this
+ * function is only applicable for directories because multiple dentries are
+ * not possible(no hardlinks)
+ * */
 void
-glusterfs_normalize_dentry (inode_t **parent, char **component,
-                          char *dentry_name)
-{
-        inode_t         *temp_inode             = NULL;
-        dentry_t        *dentry                 = NULL;
+inode_find_directory_name (inode_t *inode, const char **name) {
+        dentry_t *dentry = NULL;
 
-        GF_VALIDATE_OR_GOTO ("inode", (*parent), out);
-        GF_VALIDATE_OR_GOTO ("inode", (*component), out);
-        GF_VALIDATE_OR_GOTO ("inode", (dentry_name), out);
+        GF_VALIDATE_OR_GOTO ("inode", inode, out);
+        GF_VALIDATE_OR_GOTO ("inode", name, out);
 
-        /* After this point, there should not be "." or ".."
-         * in the path. Dot and double dots are replaced with
-         * appropriate base name and parent inode.
-         */
+        if (!IA_ISDIR (inode->ia_type))
+                return;
 
-        /* During the resolving, if it goes beyond the mount point
-         * we do lookup on the mount itself like "/.. " will be
-         * converted as "/"
-         */
-        if (strcmp (*component, ".") == 0) {
-                temp_inode = *parent;
-                *parent = inode_parent (*parent, 0, 0);
-                inode_parent_null_check (parent, temp_inode, component);
-                pthread_mutex_lock (&temp_inode->table->lock);
-                {
-                        dentry = __dentry_search_arbit (temp_inode);
-                        if (dentry) {
-                                snprintf (dentry_name, PATH_MAX, "%s",
-                                          dentry->name);
-                                *component = dentry_name;
-                        }
-                }
-                pthread_mutex_unlock (&temp_inode->table->lock);
-                inode_unref (temp_inode);
-        } else if (strcmp (*component, "..") == 0) {
-                temp_inode = *parent;
-                *parent = inode_parent (*parent, 0, 0);
-                inode_parent_null_check (parent, temp_inode, component);
-                inode_unref (temp_inode);
-
-                temp_inode = *parent;
-                *parent = inode_parent (*parent, 0, 0);
-                inode_parent_null_check (parent, temp_inode, component);
-                pthread_mutex_lock (&temp_inode->table->lock);
-                {
-                        dentry = __dentry_search_arbit (temp_inode);
-                        if (dentry) {
-                                snprintf (dentry_name, PATH_MAX, "%s",
-                                          dentry->name);
-                                *component = dentry_name;
-                        }
+        pthread_mutex_lock (&inode->table->lock);
+        {
+                dentry = __dentry_search_arbit (inode);
+                if (dentry) {
+                        *name = dentry->name;
                 }
-                pthread_mutex_unlock (&temp_inode->table->lock);
-                inode_unref (temp_inode);
         }
+        pthread_mutex_unlock (&inode->table->lock);
 out:
         return;
 }