3 files changed, 176 insertions, 0 deletions
diff --git a/dev/libSystem/src/GNUmakefile b/dev/libSystem/src/GNUmakefile
new file mode 100644
index 00000000..9b901f9f
--- /dev/null
+++ b/dev/libSystem/src/GNUmakefile
@@ -0,0 +1,16 @@
+##################################################
+# (c) Amlal El Mahrouss, all rights reserved.
+# This file is for libSystem.sys's syscall stubs.
+##################################################
+
+ASM=nasm
+FLAGS=-f win64
+
+.PHONY: error
+error:
+	@echo "==> Invalid rule."
+	@echo "==> Use sci_asm_io_<arch> instead."
+
+.PHONY: sci_asm_io_x64
+sci_asm_io_x64:
+	$(ASM) $(FLAGS) SystemCalls+IO.asm -o SystemCalls+IO.stub.obj
diff --git a/dev/libSystem/src/System.cc b/dev/libSystem/src/System.cc
new file mode 100644
index 00000000..1c28303d
--- /dev/null
+++ b/dev/libSystem/src/System.cc
@@ -0,0 +1,94 @@
+/* -------------------------------------------
+
+  Copyright (C) 2024-2025, Amlal El Mahrouss, all rights reserved.
+
+------------------------------------------- */
+
+#include <libSystem/AsmProc.h>
+#include <libSystem/System.h>
+
+/// @file SystemCalls.cc
+/// @brief Source file for the memory functions/syscalls for libSystem.sys
+
+IMPORT_C VoidPtr MmCopyMemory(_Input VoidPtr dest, _Input VoidPtr src, _Input SizeT len) {
+  if (!len || !dest || !src) {
+    return nullptr;
+  }
+
+  for (SizeT i = 0; i < len; i++) {
+    ((Char*) dest)[i] = ((Char*) src)[i];
+  }
+
+  return dest;
+}
+
+IMPORT_C SInt64 MmStrLen(const Char* in) {
+  if (!in) return 0;
+
+  SizeT len{0};
+
+  do {
+    ++len;
+  } while (in[len] != '\0');
+
+  return len;
+}
+
+IMPORT_C VoidPtr MmFillMemory(_Input VoidPtr dest, _Input SizeT len, _Input UInt8 value) {
+  if (!len || !dest) {
+    return nullptr;
+  }
+
+  for (SizeT i = 0; i < len; i++) {
+    ((Char*) dest)[i] = value;
+  }
+
+  return dest;
+}
+
+//-----------------------------------------------------------------------------------------------------------//
+/// @brief Systems Calls implementation.
+/// @internal
+//-----------------------------------------------------------------------------------------------------------//
+
+IMPORT_C Ref IoOpenFile(_Input const Char* path, _Input const Char* drv_letter) {
+  return sci_syscall_arg_3(1, reinterpret_cast<VoidPtr>(const_cast<Char*>(path)),
+                           reinterpret_cast<VoidPtr>(const_cast<Char*>(drv_letter)));
+}
+
+IMPORT_C Void IoCloseFile(_Input Ref desc) {
+  sci_syscall_arg_2(2, desc);
+}
+
+IMPORT_C UInt64 IoSeekFile(_Input Ref desc, _Input UInt64 off) {
+  auto ret = (volatile UInt64*) sci_syscall_arg_3(3, reinterpret_cast<VoidPtr>(desc),
+                                                  reinterpret_cast<VoidPtr>(&off));
+
+  MUST_PASS((*ret) != ~0UL);
+  return *ret;
+}
+
+IMPORT_C UInt64 IoTellFile(_Input Ref desc) {
+  auto ret = (volatile UInt64*) sci_syscall_arg_2(4, reinterpret_cast<VoidPtr>(desc));
+  return *ret;
+}
+
+IMPORT_C SInt32 PrintOut(_Input IORef desc, const char* fmt, ...) {
+  va_list args;
+
+  va_start(args, fmt);
+
+  auto ret = (volatile UInt64*) sci_syscall_arg_4(
+      5, reinterpret_cast<VoidPtr>(desc), reinterpret_cast<VoidPtr>(const_cast<Char*>(fmt)), args);
+
+  va_end(args);
+
+  return *ret;
+}
+
+IMPORT_C Void _rtl_assert(Bool expr, const Char* origin) {
+  if (!expr) {
+    PrintOut(nullptr, "Assertion failed: %s\r", origin);
+    PrintOut(nullptr, "Origin: %s\r", origin);
+  }
+}
diff --git a/dev/libSystem/src/SystemCalls+IO.asm b/dev/libSystem/src/SystemCalls+IO.asm
new file mode 100644
index 00000000..097046af
--- /dev/null
+++ b/dev/libSystem/src/SystemCalls+IO.asm
@@ -0,0 +1,66 @@
+;; /*
+;; *	========================================================
+;; *
+;; *	libSystem/src/SystemCalls+IO.asm
+;; * 	Copyright (C) 2024-2025, Amlal El Mahrouss, all rights reserved.
+;; *
+;; * 	========================================================
+;; */
+
+[bits 64]
+
+section .text
+
+global sci_syscall_arg_1
+global sci_syscall_arg_2
+global sci_syscall_arg_3
+global sci_syscall_arg_4
+
+sci_syscall_arg_1:
+    push rbp
+    mov rbp, rsp
+
+    mov r8, rcx
+    syscall
+
+    pop rbp
+
+    ret
+
+sci_syscall_arg_2:
+    push rbp
+    mov rbp, rsp
+
+    mov r8, rcx
+    mov r9, rdx
+    syscall
+    pop rbp
+
+    ret
+
+sci_syscall_arg_3:
+    push rbp
+    mov rbp, rsp
+
+    mov r8, rcx
+    mov r9, rdx
+    mov r10, rbx
+
+    syscall
+    pop rbp
+
+    ret
+
+sci_syscall_arg_4:
+    push rbp
+    mov rbp, rsp
+
+    mov r8, rcx
+    mov r9, rdx
+    mov r10, rbx
+    mov r11, rax
+
+    syscall
+    pop rbp
+
+    ret