Add NBD-based UF2 file server

brick/uf2daemon/uf2.h

@@ -0,0 +1,37 @@
+#ifndef UF2_H
+#define UF2_H 1
+
+#include "uf2format.h"
+#include <stdio.h>
+#include <string.h>
+
+#ifndef INDEX_URL
+#define INDEX_URL "https://www.pxt.io/"
+#endif
+
+#define UF2_VERSION_BASE "v0.1.0"
+
+// needs to be more than ~4200 and less than ~65000 (to force FAT16)
+#define NUM_FAT_BLOCKS 65000
+
+#define UF2_VERSION UF2_VERSION_BASE " F"
+
+//! Static block size for all memories
+#define UDI_MSC_BLOCK_SIZE 512L
+
+void read_block(uint32_t block_no, uint8_t *data);
+
+void write_block(uint32_t block_no, uint8_t *data);
+
+#define CONCAT_1(a, b) a##b
+#define CONCAT_0(a, b) CONCAT_1(a, b)
+#define STATIC_ASSERT(e)                                                       \
+  enum { CONCAT_0(_static_assert_, __LINE__) = 1 / ((e) ? 1 : 0) }
+
+extern const char infoUf2File[];
+
+void readAll(int fd, void *dst, uint32_t length);
+
+STATIC_ASSERT(sizeof(UF2_Block) == 512);
+
+#endif