fundamental: split out unaligned_{read|write}_ne{16,32,64}() helpers into unaligned-fundamental.h

Let's allow using this in code shared between userspace and EFI mode.

Also, don't implement these functions via endianness conversions given
we don't actually want to convert endianess here.

1 files changed, 40 insertions, 0 deletions

diff --git a/src/fundamental/unaligned-fundamental.h b/src/fundamental/unaligned-fundamental.h
new file mode 100644
index 0000000000..a4c810a5fc
--- /dev/null
+++ b/src/fundamental/unaligned-fundamental.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <stdint.h>
+
+static inline uint16_t unaligned_read_ne16(const void *_u) {
+        const struct __attribute__((__packed__, __may_alias__)) { uint16_t x; } *u = _u;
+
+        return u->x;
+}
+
+static inline uint32_t unaligned_read_ne32(const void *_u) {
+        const struct __attribute__((__packed__, __may_alias__)) { uint32_t x; } *u = _u;
+
+        return u->x;
+}
+
+static inline uint64_t unaligned_read_ne64(const void *_u) {
+        const struct __attribute__((__packed__, __may_alias__)) { uint64_t x; } *u = _u;
+
+        return u->x;
+}
+
+static inline void unaligned_write_ne16(void *_u, uint16_t a) {
+        struct __attribute__((__packed__, __may_alias__)) { uint16_t x; } *u = _u;
+
+        u->x = a;
+}
+
+static inline void unaligned_write_ne32(void *_u, uint32_t a) {
+        struct __attribute__((__packed__, __may_alias__)) { uint32_t x; } *u = _u;
+
+        u->x = a;
+}
+
+static inline void unaligned_write_ne64(void *_u, uint64_t a) {
+        struct __attribute__((__packed__, __may_alias__)) { uint64_t x; } *u = _u;
+
+        u->x = a;
+}