os: fix swap_bytes_u64 (vlang#24033)

Author: tankf33der

vlib/os/file_le_be.c.v

@@ -74,17 +74,34 @@ pub fn (mut f File) read_u8() !u8 {
 
 @[inline]
 fn swap_bytes_u16(x u16) u16 {
-	return ((x >> 8) & 0x00FF) | ((x << 8) & 0xFF00)
+	// vfmt off
+	return ((x >> 8) & 0x00FF) |
+	       ((x << 8) & 0xFF00)
+	// vfmt on
 }
 
 @[inline]
 fn swap_bytes_u32(x u32) u32 {
-	return ((x >> 24) & 0x0000_00FF) | ((x >> 8) & 0x0000_FF00) | ((x << 8) & 0x00FF_0000) | ((x << 24) & 0xFF00_0000)
+	// vfmt off
+	return ((x >> 24) & 0x0000_00FF) |
+	       ((x >> 8)  & 0x0000_FF00) |
+	       ((x << 8)  & 0x00FF_0000) |
+	       ((x << 24) & 0xFF00_0000)
+	// vfmt on
 }
 
 @[inline]
 fn swap_bytes_u64(x u64) u64 {
-	return ((x >> 40) & 0x00000000_0000FF00) | ((x >> 24) & 0x00000000_00FF0000) | ((x >> 8) & 0x00000000_FF000000) | ((x << 8) & 0x000000FF_00000000) | ((x << 24) & 0x0000FF00_00000000) | ((x << 40) & 0x00FF0000_00000000) | ((x << 56) & 0xFF000000_00000000)
+	// vfmt off
+	return ((x >> 56) & 0x00000000_000000FF) |
+	       ((x >> 40) & 0x00000000_0000FF00) |
+	       ((x >> 24) & 0x00000000_00FF0000) |
+	       ((x >> 8)  & 0x00000000_FF000000) |
+	       ((x << 8)  & 0x000000FF_00000000) |
+	       ((x << 24) & 0x0000FF00_00000000) |
+	       ((x << 40) & 0x00FF0000_00000000) |
+	       ((x << 56) & 0xFF000000_00000000)
+	// vfmt on
 }
 
 fn swap_bytes[T](input T) T {

vlib/os/file_le_be_test.v

@@ -19,46 +19,54 @@ fn test_write_be_read_be() {
 	mut f := os.open_file(fname, 'wb')!
 	f.write_be[u8](0x08)!
 	f.write_be[u16](0x1617)!
-	f.write_be[u32](0x3233)!
-	f.write_be[u64](0x6465)!
+	f.write_be[u32](0x30313233)!
+	f.write_be[u64](0x5859606162636465)!
 	f.write_u8(123)!
 	f.write_u8(42)!
 	f.close()
 	// vfmt off
 	assert os.read_bytes(fname)! == [
 		u8(0x08),
 		0x16, 0x17,
-		0x00, 0x00, 0x32, 0x33,
-		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x64, 0x65,
+		0x30, 0x31, 0x32, 0x33,
+		0x58, 0x59, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65,
 		123, 42
 	]
 	// vfmt on
+	mut r := os.open_file(fname, 'rb')!
+	assert r.read_be[u8]()! == 0x08
+	assert r.read_be[u16]()! == 0x1617
+	assert r.read_be[u32]()! == 0x30313233
+	assert r.read_be[u64]()! == 0x5859606162636465
+	assert r.read_u8()! == 123
+	assert r.read_u8()! == 42
+	r.close()
 }
 
 fn test_write_le_read_le() {
 	fname := os.join_path(tfolder, 'f_le')
 	mut f := os.open_file(fname, 'wb')!
 	f.write_le[u8](0x08)!
 	f.write_le[u16](0x1617)!
-	f.write_le[u32](0x3233)!
-	f.write_le[u64](0x6465)!
+	f.write_le[u32](0x30313233)!
+	f.write_le[u64](0x5859606162636465)!
 	f.write_u8(12)!
 	f.write_u8(34)!
 	f.close()
 	// vfmt off
-	assert os.read_bytes('f_le')! == [
+	assert os.read_bytes(fname)! == [
 		u8(0x08),
 		0x17, 0x16,
-		0x33, 0x32, 0x00, 0x00,
-		0x65, 0x64, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x33, 0x32, 0x31, 0x30,
+		0x65, 0x64, 0x63, 0x62, 0x61, 0x60, 0x59, 0x58,
 		12, 34
 	]
 	// vfmt on
 	mut r := os.open_file(fname, 'rb')!
 	assert r.read_le[u8]()! == 0x08
 	assert r.read_le[u16]()! == 0x1617
-	assert r.read_le[u32]()! == 0x3233
-	assert r.read_le[u64]()! == 0x6465
+	assert r.read_le[u32]()! == 0x30313233
+	assert r.read_le[u64]()! == 0x5859606162636465
 	assert r.read_u8()! == 12
 	assert r.read_u8()! == 34
 	r.close()