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authorFelix Morgner <felix.morgner@gmail.com>2026-02-19 13:30:45 +0100
committerFelix Morgner <felix.morgner@gmail.com>2026-02-19 13:30:45 +0100
commite6d59a7b506f610b82340b62457f9dd9ad0cb53d (patch)
treeb83affc4789146822a9fdbda88402b87c5f0fa28 /src/snake.S
parente34239cf2bdb6bd810826b82c2a66873bd0881e2 (diff)
downloadsnake.s-e6d59a7b506f610b82340b62457f9dd9ad0cb53d.tar.xz
snake.s-e6d59a7b506f610b82340b62457f9dd9ad0cb53d.zip
feat: integrate basic CMocka tests
Diffstat (limited to 'src/snake.S')
-rw-r--r--src/snake.S77
1 files changed, 77 insertions, 0 deletions
diff --git a/src/snake.S b/src/snake.S
new file mode 100644
index 0000000..00d66e2
--- /dev/null
+++ b/src/snake.S
@@ -0,0 +1,77 @@
+//! @file snake.S
+//!
+//! Type definitions, sizes, and the interface for the snake.
+
+#include "helpers/function.S"
+
+#define OFFSET_snake_t_x 0
+#define SIZE_snake_t_x 4
+
+#define OFFSET_snake_t_y OFFSET_snake_t_x + SIZE_snake_t_x
+#define SIZE_snake_t_y 4
+
+#define OFFSET_snake_t_length OFFSET_snake_t_y + SIZE_snake_t_y
+#define SIZE_snake_t_length 4
+
+#define OFFSET_snake_t_direction OFFSET_snake_t_length + SIZE_snake_t_length
+#define SIZE_snake_t_direction 1
+
+#define OFFSET_snake_t_padding OFFSET_snake_t_direction + SIZE_snake_t_direction
+#define SIZE_snake_t_padding 3
+
+#define SIZE_snake_t OFFSET_snake_t_padding + SIZE_snake_t_padding
+
+#ifndef __STDC_VERSION__
+
+.section .text
+
+ //! @fn void snake_init(snake_t * self, int x, int y, int length)
+ //! @param (%rdi) self the object to initialize
+ //! @param (%esi) x the x position of the head of the snake
+ //! @param (%edx) y the y position of the head of the snake
+ //! @param (%ecx) length the length of the snake
+ function_begin snake_init
+
+ test %rdi, %rdi
+ jz .Lexit_snake_init
+
+ mov %esi, OFFSET_snake_t_x(%rdi)
+ mov %edx, OFFSET_snake_t_y(%rdi)
+ mov %ecx, OFFSET_snake_t_length(%rdi)
+ xor %al, %al
+ mov %al, OFFSET_snake_t_direction(%rdi)
+
+ function_end
+
+#else
+
+#include <stddef.h>
+
+typedef struct {
+ int x;
+ int y;
+ int length;
+ char direction;
+ char padding[3];
+} snake_t;
+
+static_assert(sizeof(snake_t) == SIZE_snake_t);
+
+static_assert(offsetof(snake_t, x) == OFFSET_snake_t_x);
+static_assert(sizeof(((snake_t*)0)->x) == SIZE_snake_t_x);
+
+static_assert(offsetof(snake_t, y) == OFFSET_snake_t_y);
+static_assert(sizeof(((snake_t*)0)->y) == SIZE_snake_t_y);
+
+static_assert(offsetof(snake_t, length) == OFFSET_snake_t_length);
+static_assert(sizeof(((snake_t*)0)->length) == SIZE_snake_t_length);
+
+static_assert(offsetof(snake_t, direction) == OFFSET_snake_t_direction);
+static_assert(sizeof(((snake_t*)0)->direction) == SIZE_snake_t_direction);
+
+static_assert(offsetof(snake_t, padding) == OFFSET_snake_t_padding);
+static_assert(sizeof(((snake_t*)0)->padding) == SIZE_snake_t_padding);
+
+void snake_init(snake_t * self, int x, int y, int length);
+
+#endif \ No newline at end of file