1 files changed, 46 insertions, 0 deletions
diff --git a/stm/lexerfatfs.c b/stm/lexerfatfs.c
new file mode 100644
index 0000000000..5dcaca1606
--- /dev/null
+++ b/stm/lexerfatfs.c
@@ -0,0 +1,46 @@
+#include <stdint.h>
+#include <stdio.h>
+
+#include "ff.h"
+
+#include "misc.h"
+#include "lexer.h"
+#include "lexerfatfs.h"
+
+unichar file_buf_next_char(mp_lexer_file_buf_t *fb) {
+    if (fb->pos >= fb->len) {
+        if (fb->len < sizeof(fb->buf)) {
+            return MP_LEXER_CHAR_EOF;
+        } else {
+            UINT n;
+            f_read(&fb->fp, fb->buf, sizeof(fb->buf), &n);
+            if (n == 0) {
+                return MP_LEXER_CHAR_EOF;
+            }
+            fb->len = n;
+            fb->pos = 0;
+        }
+    }
+    return fb->buf[fb->pos++];
+}
+
+void file_buf_close(mp_lexer_file_buf_t *fb) {
+    f_close(&fb->fp);
+}
+
+mp_lexer_t *mp_lexer_new_from_file(const char *filename, mp_lexer_file_buf_t *fb) {
+    FRESULT res = f_open(&fb->fp, filename, FA_READ);
+    if (res != FR_OK) {
+        return NULL;
+    }
+    UINT n;
+    f_read(&fb->fp, fb->buf, sizeof(fb->buf), &n);
+    fb->len = n;
+    fb->pos = 0;
+    return mp_lexer_new(filename, fb, (mp_lexer_stream_next_char_t)file_buf_next_char, (mp_lexer_stream_close_t)file_buf_close);
+}
+
+mp_lexer_t *mp_import_open_file(qstr mod_name) {
+    printf("import not implemented\n");
+    return NULL;
+}