1 files changed, 397 insertions, 0 deletions
diff --git a/euler/source/syscall.cpp b/euler/source/syscall.cpp
new file mode 100644
index 0000000..b3ed3a8
--- /dev/null
+++ b/euler/source/syscall.cpp
@@ -0,0 +1,397 @@
+#include <euler/syscall.hpp>
+
+extern "C" void __euler_do_syscall(
+  uint64_t &rax, uint64_t &rdi, uint64_t &rsi, uint64_t &rdx);
+
+namespace euler::syscall {
+
+  encoded_color encode_color(
+    uint8_t r, uint8_t g, uint8_t b) {
+
+    uint64_t rax = 0;
+    uint64_t rdi = (uint32_t)r | ((uint32_t)g << 8) | ((uint32_t)b << 16);
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (encoded_color)(rax & 0xffffffff);
+
+  }
+
+  void get_framebuffer(
+    encoded_color *&buffer_out, uint32_t &width_out,
+    uint32_t &height_out, uint32_t &pitch_out) {
+
+    uint64_t rax = 1;
+    uint64_t rdi;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    buffer_out = (encoded_color *)rax;
+    width_out = rdi & 0xffffffff;
+    height_out = rdi >> 32;
+    pitch_out = rsi & 0xffffffff;
+
+  }
+
+  stream_result open_file(
+    const std::string &file_path, bool allow_creation,
+    bool only_allow_creation, stream_handle &handle_out) {
+
+    uint64_t rax = 2;
+    uint64_t rdi = (uint64_t)file_path.data();
+    uint64_t rsi = file_path.size();
+    uint64_t rdx =
+      (     allow_creation ? 0x1 : 0x0) |
+      (only_allow_creation ? 0x2 : 0x0);
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    handle_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  [[noreturn]] void end_this_thread(int32_t exit_code) {
+
+    uint64_t rax = 3;
+    uint64_t rdi = (uint32_t)exit_code;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    __builtin_unreachable();
+
+  }
+
+  void *get_new_pages(uint64_t n_pages) {
+
+    uint64_t rax = 4;
+    uint64_t rdi = n_pages;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (void *)rax;
+
+  }
+
+  std::variant<mouse_packet, key_packet> get_input_packet() {
+
+    uint64_t rax = 5;
+    uint64_t rdi;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    if (rax & 0x80)
+      return (mouse_packet){
+        .  left_button_down = (rax & 0x01) != 0,
+        . right_button_down = (rax & 0x02) != 0,
+        .middle_button_down = (rax & 0x04) != 0,
+        .x_changed = (int16_t)(rdi & 0xffff),
+        .y_changed = (int16_t)(rsi & 0xffff)
+      };
+
+    return (key_packet){
+      .was_key_up_event = (rdi & 0x40000) != 0,
+      .        num_lock = (rdi & 0x20000) != 0,
+      .       caps_lock = (rdi & 0x10000) != 0,
+      .       right_win = (rdi &  0x8000) != 0,
+      .        left_win = (rdi &  0x4000) != 0,
+      .       right_alt = (rdi &  0x2000) != 0,
+      .        left_alt = (rdi &  0x1000) != 0,
+      .      right_ctrl = (rdi &   0x800) != 0,
+      .       left_ctrl = (rdi &   0x400) != 0,
+      .     right_shift = (rdi &   0x200) != 0,
+      .      left_shift = (rdi &   0x100) != 0,
+      .        key_code = (uint8_t)(rdi & 0xff)
+    };
+
+  }
+
+  void create_private_socket(
+    stream_handle &end_1_out, stream_handle &end_2_out) {
+
+    uint64_t rax = 6;
+    uint64_t rdi;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    end_1_out = rax;
+    end_2_out = rdi;
+
+  }
+
+  stream_result create_socket_listener(
+    const std::string &id, listener_handle &handle_out) {
+
+    uint64_t rax = 7;
+    uint64_t rdi = (uint64_t)id.data();
+    uint64_t rsi = id.size();
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    handle_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  void stop_socket_listener(listener_handle handle) {
+
+    uint64_t rax = 8;
+    uint64_t rdi = handle;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+  }
+
+  stream_result accept_socket_connection(
+    listener_handle listener, stream_handle &stream_out) {
+
+    uint64_t rax = 9;
+    uint64_t rdi = listener;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    stream_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  stream_result connect_to_socket(
+    const std::string &id, stream_handle &handle_out) {
+
+    uint64_t rax = 10;
+    uint64_t rdi = (uint64_t)id.data();
+    uint64_t rsi = id.size();
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    handle_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  void close_stream(stream_handle handle) {
+
+    uint64_t rax = 11;
+    uint64_t rdi = handle;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+  }
+
+  stream_result seek_stream(
+    stream_handle handle, seek_from from, int64_t offset) {
+
+    uint64_t rax = 12;
+    uint64_t rdi = (uint64_t)handle;
+    uint64_t rsi = (uint8_t)from;
+    uint64_t rdx = (uint64_t)offset;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (stream_result)rax;
+
+  }
+
+  stream_result read_from_stream(
+    stream_handle handle, uint64_t bytes, void *into) {
+
+    uint64_t rax = 13;
+    uint64_t rdi = (uint64_t)handle;
+    uint64_t rsi = bytes;
+    uint64_t rdx = (uint64_t)into;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (stream_result)rax;
+
+  }
+
+  stream_result write_to_stream(
+    stream_handle handle, uint64_t bytes, const void *from) {
+
+    uint64_t rax = 14;
+    uint64_t rdi = (uint64_t)handle;
+    uint64_t rsi = bytes;
+    uint64_t rdx = (uint64_t)from;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (stream_result)rax;
+
+  }
+
+  stream_result get_stream_length(
+    stream_handle handle, uint64_t &length_out) {
+
+    uint64_t rax = 15;
+    uint64_t rdi = (uint64_t)handle;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    length_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  stream_result start_process(
+    const std::string &file_path,
+    const std::vector<std::pair<std::string, std::string>> &environment_variables,
+    const std::vector<std::pair<stream_handle, stream_result>> &gifted_streams,
+    process_handle &handle_out) {
+
+    std::vector<uint64_t> ev_structs(environment_variables.size() * 4);
+    for (size_t i = 0; i < environment_variables.size(); ++i) {
+      ev_structs[i * 4]     =           environment_variables[i]. first.size();
+      ev_structs[i * 4 + 1] = (uint64_t)environment_variables[i]. first.data();
+      ev_structs[i * 4 + 2] =           environment_variables[i].second.size();
+      ev_structs[i * 4 + 3] = (uint64_t)environment_variables[i].second.data();
+    }
+
+    std::vector<uint64_t> gs_structs(gifted_streams.size() * 2);
+    for (size_t i = 0; i < environment_variables.size(); ++i) {
+      gs_structs[i * 2]     = (uint64_t)gifted_streams[i]. first;
+      gs_structs[i * 2 + 1] = (uint64_t)gifted_streams[i].second;
+    }
+
+    uint64_t psi_struct[] = {
+                  file_path.size(), (uint64_t) file_path.data(),
+      environment_variables.size(), (uint64_t)ev_structs.data(),
+             gifted_streams.size(), (uint64_t)gs_structs.data()
+    };
+
+    uint64_t rax = 16;
+    uint64_t rdi = (uint64_t)psi_struct;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    handle_out = rdi;
+    return (stream_result)rax;
+
+  }
+
+  [[noreturn]] void end_this_process(int32_t exit_code) {
+
+    uint64_t rax = 17;
+    uint64_t rdi = (uint32_t)exit_code;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    __builtin_unreachable();
+
+  }
+
+  stream_result set_stream_length(
+    stream_handle handle, uint64_t new_length) {
+
+    uint64_t rax = 18;
+    uint64_t rdi = (uint64_t)handle;
+    uint64_t rsi = new_length;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return (stream_result)rax;
+
+  }
+
+  stream_result get_other_end_process_handle(
+    stream_handle stream, process_handle &process_out) {
+
+    uint64_t rax = 19;
+    uint64_t rdi = (uint64_t)stream;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    process_out = (process_handle)rdi;
+    return (stream_result)rax;
+
+  }
+
+  //entry_point must not return
+  void start_thread(void (*entry_point)(uint64_t), uint64_t arg) {
+
+    uint64_t rax = 20;
+    uint64_t rdi = (uint64_t)entry_point;
+    uint64_t rsi = arg;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+  }
+
+  //entry_point must not return
+  void start_thread(void (*entry_point)()) {
+
+    uint64_t rax = 20;
+    uint64_t rdi = (uint64_t)entry_point;
+    uint64_t rsi = 0;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+  }
+
+  //return value is number of bytes cleared
+  uint64_t clear_socket_read_queue(stream_handle handle) {
+
+    uint64_t rax = 21;
+    uint64_t rdi = handle;
+    uint64_t rsi;
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    return rax;
+
+  }
+
+  //this function has a race condition if the variable is changed
+  //or unset by another thread between the two syscalls.
+  std::optional<std::string> try_get_environment_variable(
+    const std::string &name) {
+
+    uint64_t rax = 22;
+    uint64_t rdi = (uint64_t)name.data();
+    uint64_t rsi = name.size();
+    uint64_t rdx;
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+
+    if (rax == (uint64_t)-1)
+      return {};
+
+    std::string s;
+    s.resize(rax);
+
+    rax = 23;
+    rdi = (uint64_t)name.data();
+    rsi = name.size();
+    rdx = (uint64_t)s.data();
+
+    __euler_do_syscall(rax, rdi, rsi, rdx);
+    //do i need to tell gcc that s is modified?
+
+    return s;
+
+  }
+
+}