MP jpegdec: fix width/height functions by opening file/buffer earlier

Open file/buffer in open function rather than on demand.
Also adds a close function for the user.

micropython/modules/jpegdec/jpegdec.c

@@ -3,6 +3,7 @@
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(JPEG_del_obj, _JPEG_del);
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(JPEG_openRAM_obj, _JPEG_openRAM);
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(JPEG_openFILE_obj, _JPEG_openFILE);
+STATIC MP_DEFINE_CONST_FUN_OBJ_2(JPEG_close_obj, _JPEG_close);
 STATIC MP_DEFINE_CONST_FUN_OBJ_KW(JPEG_decode_obj, 1, _JPEG_decode);
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(JPEG_getWidth_obj, _JPEG_getWidth);
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(JPEG_getHeight_obj, _JPEG_getHeight);
@@ -12,6 +13,7 @@ STATIC const mp_rom_map_elem_t JPEG_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&JPEG_del_obj) },
     { MP_ROM_QSTR(MP_QSTR_open_RAM), MP_ROM_PTR(&JPEG_openRAM_obj) },
     { MP_ROM_QSTR(MP_QSTR_open_file), MP_ROM_PTR(&JPEG_openFILE_obj) },
+    { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&JPEG_close_obj) },
     { MP_ROM_QSTR(MP_QSTR_decode), MP_ROM_PTR(&JPEG_decode_obj) },
     { MP_ROM_QSTR(MP_QSTR_get_width), MP_ROM_PTR(&JPEG_getWidth_obj) },
     { MP_ROM_QSTR(MP_QSTR_get_height), MP_ROM_PTR(&JPEG_getHeight_obj) },

micropython/modules/jpegdec/jpegdec.cpp

@@ -205,8 +205,20 @@ mp_obj_t _JPEG_openFILE(mp_obj_t self_in, mp_obj_t filename) {
     _JPEG_obj_t *self = MP_OBJ_TO_PTR2(self_in, _JPEG_obj_t);
 
     // TODO Check for valid filename, and maybe that file exists?
+    if (!mp_obj_is_str(self->file))
+        return mp_const_false;
 
-    self->file = filename;
+    GET_STR_DATA_LEN(filename, str, str_len);
+
+    result = self->jpeg->open(
+        (const char*)str,
+        jpegdec_open_callback,
+        jpegdec_close_callback,
+        jpegdec_read_callback,
+        jpegdec_seek_callback,
+        JPEGDraw);
+
+    if(result != 1) mp_raise_msg(&mp_type_RuntimeError, "JPEG: could not read file.");
 
     return mp_const_true;
 }
@@ -217,11 +229,24 @@ mp_obj_t _JPEG_openRAM(mp_obj_t self_in, mp_obj_t buffer) {
 
     // TODO Check for valid buffer
 
-    self->file = buffer;
+    mp_get_buffer_raise(buffer, &self->buf, MP_BUFFER_READ);
+
+    result = self->jpeg->openRAM((uint8_t *)self->buf.buf, self->buf.len, JPEGDraw);
+
+    if(result != 1) mp_raise_msg(&mp_type_RuntimeError, "JPEG: could not read buffer.");
 
     return mp_const_true;
 }
 
+// close
+mp_obj_t _JPEG_close(mp_obj_t self_in) {
+    _JPEG_obj_t *self = MP_OBJ_TO_PTR2(self_in, _JPEG_obj_t);
+
+    self->jpeg->close();
+
+    return mp_const_none;
+}
+
 // decode
 mp_obj_t _JPEG_decode(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     enum { ARG_self, ARG_x, ARG_y, ARG_scale, ARG_dither };
@@ -244,31 +269,6 @@ mp_obj_t _JPEG_decode(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args
 
     current_flags = args[ARG_dither].u_obj == mp_const_false ? FLAG_NO_DITHER : 0;
 
-    // Just-in-time open of the filename/buffer we stored in self->file via open_RAM or open_file
-
-    // Source is a filename
-    int result = -1;
-
-    if(mp_obj_is_str(self->file)){
-        GET_STR_DATA_LEN(self->file, str, str_len);
-
-        result = self->jpeg->open(
-            (const char*)str,
-            jpegdec_open_callback,
-            jpegdec_close_callback,
-            jpegdec_read_callback,
-            jpegdec_seek_callback,
-            JPEGDraw);
-
-    // Source is a buffer
-    } else {
-        mp_get_buffer_raise(self->file, &self->buf, MP_BUFFER_READ);
-
-        result = self->jpeg->openRAM((uint8_t *)self->buf.buf, self->buf.len, JPEGDraw);
-    }
-
-    if(result != 1) mp_raise_msg(&mp_type_RuntimeError, "JPEG: could not read file/buffer.");
-
     // Force a specific data output type to best match our PicoGraphics buffer
     switch(self->graphics->graphics->pen_type) {
         case PicoGraphics::PEN_RGB332:
@@ -297,9 +297,6 @@ mp_obj_t _JPEG_decode(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args
 
     current_flags = 0;
 
-    // Close the file since we've opened it on-demand
-    self->jpeg->close();
-
     return result == 1 ? mp_const_true : mp_const_false;
 }
 

micropython/modules/jpegdec/jpegdec.h

@@ -7,6 +7,7 @@ extern mp_obj_t _JPEG_make_new(const mp_obj_type_t *type, size_t n_args, size_t
 extern mp_obj_t _JPEG_del(mp_obj_t self_in);
 extern mp_obj_t _JPEG_openRAM(mp_obj_t self_in, mp_obj_t buffer);
 extern mp_obj_t _JPEG_openFILE(mp_obj_t self_in, mp_obj_t filename);
+extern mp_obj_t _JPEG_close(mp_obj_t self_in);
 extern mp_obj_t _JPEG_decode(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args);
 extern mp_obj_t _JPEG_getWidth(mp_obj_t self_in);
 extern mp_obj_t _JPEG_getHeight(mp_obj_t self_in);