fix(qrcode): fix crash due to buf_unalign modification (#4987)

Signed-off-by: Xu Xingliang <xuxingliang@xiaomi.com>

src/libs/qrcode/lv_qrcode.c

@@ -63,11 +63,12 @@ void lv_qrcode_set_size(lv_obj_t * obj, int32_t size)
 {
     LV_ASSERT_OBJ(obj, MY_CLASS);
 
-    lv_image_dsc_t * img_dsc = lv_canvas_get_image(obj);
-    void * buf = (void *)img_dsc->data;
+    void * buf = (void *)lv_canvas_get_buf(obj);
+    if(buf) lv_draw_buf_free(buf);
 
-    uint32_t buf_size = LV_CANVAS_BUF_SIZE(size, size, 1, LV_DRAW_BUF_STRIDE_ALIGN);
-    buf = lv_realloc(buf, buf_size);
+    size_t buf_size = lv_draw_buf_width_to_stride(size, LV_COLOR_FORMAT_I1) * size;
+    buf_size += 8; /*palette*/
+    buf = lv_draw_buf_malloc(buf_size, LV_COLOR_FORMAT_I1);
     LV_ASSERT_MALLOC(buf);
     if(buf == NULL) {
         LV_LOG_ERROR("malloc failed for canvas buffer");
@@ -155,7 +156,7 @@ lv_result_t lv_qrcode_update(lv_obj_t * obj, const void * data, uint32_t data_le
     /* Copy the qr code canvas:
      * A simple `lv_canvas_set_px` would work but it's slow for so many pixels.
      * So buffer 1 byte (8 px) from the qr code and set it in the canvas image */
-    uint32_t row_byte_cnt = (img_dsc->header.w + 7) >> 3;
+    uint32_t row_byte_cnt = img_dsc->header.stride;
     int y;
     for(y = margin; y < scaled + margin; y += scale) {
         uint8_t b = 0;
@@ -234,7 +235,7 @@ static void lv_qrcode_destructor(const lv_obj_class_t * class_p, lv_obj_t * obj)
         return;
     }
 
-    lv_free((void *)lv_canvas_get_image(obj));
+    lv_draw_buf_free((void *)lv_canvas_get_buf(obj));
     img_dsc->data = NULL;
 }
 

tests/src/test_cases/libs/test_qrcode.c

@@ -0,0 +1,59 @@
+#if LV_BUILD_TEST
+#include "../lvgl.h"
+
+#include "unity/unity.h"
+
+#if LV_USE_QRCODE
+
+static lv_obj_t * active_screen = NULL;
+
+void setUp(void)
+{
+    active_screen = lv_screen_active();
+}
+
+void tearDown(void)
+{
+    lv_obj_clean(active_screen);
+}
+
+void test_barcode_normal(void)
+{
+    lv_color_t bg_color = lv_palette_lighten(LV_PALETTE_LIGHT_BLUE, 5);
+    lv_color_t fg_color = lv_palette_darken(LV_PALETTE_BLUE, 4);
+
+    lv_obj_t * qr = lv_qrcode_create(active_screen);
+    TEST_ASSERT_NOT_NULL(qr);
+    lv_qrcode_set_size(qr, 150);
+    lv_qrcode_set_dark_color(qr, fg_color);
+    lv_qrcode_set_light_color(qr, bg_color);
+
+    /*Set data*/
+    const char * data = "https://lvgl.io";
+    lv_result_t res = lv_qrcode_update(qr, data, strlen(data));
+    TEST_ASSERT_EQUAL(res, LV_RESULT_OK);
+    lv_obj_center(qr);
+
+    /*Add a border with bg_color*/
+    lv_obj_set_style_border_color(qr, bg_color, 0);
+    lv_obj_set_style_border_width(qr, 5, 0);
+    TEST_ASSERT_EQUAL_SCREENSHOT("libs/qrcode_1.png");
+}
+
+#else
+
+void setUp(void)
+{
+}
+
+void tearDown(void)
+{
+}
+
+void test_barcode_normal(void)
+{
+}
+
+#endif
+
+#endif