Merge pull request lvgl-micropython#399 from MicroPythonOS/add-directory-support-to-fs_driver

Add directory support to fs_driver. That means the file explorer in LVGL will now work properly!!!

Author: kdschlosser

api_drivers/py_api_drivers/fs_driver.py

@@ -74,6 +74,41 @@ def _fs_write_cb(drv, fs_file, buf, btw, bw):
 
     return lv.FS_RES.OK
 
+def _fs_dir_open_cb(drv, path):
+    #print(f"_fs_dir_open_cb for path '{path}'")
+    try:
+        import os # for ilistdir()
+        return {'iterator' : os.ilistdir(path)}
+    except Exception as e:
+        print(f"_fs_dir_open_cb exception: {e}")
+        return None
+
+def _fs_dir_read_cb(drv, lv_fs_dir_t, buf, btr):
+    try:
+        iterator = lv_fs_dir_t.__cast__()['iterator']
+        nextfile = iterator.__next__()
+        #print(f"nextfile: {nextfile}")
+        filename = nextfile[0]
+        entry_type = nextfile[1]  # Type field
+        if entry_type == 0x4000:
+            #print(f"{filename} is a directory")
+            filename = f"/{filename}"
+        # Convert filename to bytes with null terminator
+        tmp_data_bytes = filename.encode() + b'\x00'
+        buf.__dereference__(btr)[0:len(tmp_data_bytes)] = tmp_data_bytes
+        return lv.FS_RES.OK
+    except StopIteration:
+        # Clear buffer and return FS_ERR when iteration ends
+        buf.__dereference__(btr)[0:1] = b'\x00'  # Empty string (null byte)
+        return lv.FS_RES.NOT_EX  # Next entry "does not exist"
+    except Exception as e:
+        print(f"_fs_dir_read_cb exception: {e}")
+        return lv.FS_RES.UNKNOWN
+
+def _fs_dir_close_cb(drv, lv_fs_dir_t):
+    #print(f"_fs_dir_close_cb called")
+    # No need to cleanup the iterator so nothing to do
+    return lv.FS_RES.OK
 
 def fs_register(fs_drv, letter, cache_size=500):
 
@@ -85,6 +120,9 @@ def fs_register(fs_drv, letter, cache_size=500):
     fs_drv.seek_cb = _fs_seek_cb
     fs_drv.tell_cb = _fs_tell_cb
     fs_drv.close_cb = _fs_close_cb
+    fs_drv.dir_open_cb = _fs_dir_open_cb
+    fs_drv.dir_read_cb = _fs_dir_read_cb
+    #fs_drv.dir_close_cb = _fs_dir_close_cb
 
     if cache_size >= 0:
         fs_drv.cache_size = cache_size

gen/python_api_gen_mpy.py

@@ -2865,12 +2865,18 @@ def create_helper_struct(struct_str):
 
 
 def build_callback_func_arg(arg, index, func, func_name = None):
-    arg_type = get_type(arg.type, remove_quals = True)
+    arg_type = get_type(arg.type, remove_quals = False)
     cast = '(void*)' if isinstance(arg.type, c_ast.PtrDecl) else '' # needed when field is const. casting to void overrides it
-    if arg_type not in lv_to_mp or not lv_to_mp[arg_type]:
-        try_generate_type(arg.type)
+
+    if arg_type == 'char *':
+        converter = 'ptr_to_mp'
+    else:
+        arg_type = get_type(arg.type, remove_quals = True)
         if arg_type not in lv_to_mp or not lv_to_mp[arg_type]:
-            raise MissingConversionException("Callback: Missing conversion to %s" % arg_type)
+            try_generate_type(arg.type)
+            if arg_type not in lv_to_mp or not lv_to_mp[arg_type]:
+                raise MissingConversionException("Callback: Missing conversion to %s" % arg_type)
+        converter = lv_to_mp[arg_type]
 
     arg_metadata = {'c_type': arg_type, 'py_type': get_py_type(arg_type)}
 
@@ -2880,8 +2886,9 @@ def build_callback_func_arg(arg, index, func, func_name = None):
         arg_metadata['name'] = None
 
     callback_metadata[func_name]['args'].append(arg_metadata)
+
     return 'mp_args[{i}] = {convertor}({cast}arg{i});'.format(
-                convertor = lv_to_mp[arg_type],
+                convertor = converter,
                 i = index, cast = cast)