update

13 files changed, 480 insertions, 0 deletions

diff --git a/libraries/euler/allocator.cpp b/libraries/euler/allocator.cpp
new file mode 100644
index 0000000..5242df1
--- /dev/null
+++ b/libraries/euler/allocator.cpp
@@ -0,0 +1,147 @@
+#include <euler/syscall.hpp>
+
+//i guess we could figure out which parts of the pages the kernel allocated to
+//load the application were not actually needed and add those to the memory
+//that is available to be allocated, but whatever.
+
+namespace euler::allocator {
+
+  struct block_info {
+    //vaddr, divisible by size
+    uint64_t start;
+    //power of 2, 0 for unused
+    uint64_t size;
+  };
+
+  struct block_info_page {
+    block_info infos[255];
+    block_info_page *next;
+  };
+
+  static_assert(sizeof(block_info_page) == 4088);
+
+  static block_info_page *first_bi_page = 0;
+
+  static block_info *try_find_block(uint64_t start, uint64_t size) {
+    for (block_info_page *bip = first_bi_page; bip; bip = bip->next)
+      for (int i = 0; i < 255; ++i)
+        if (bip->infos[i].start == start && bip->infos[i].size == size)
+          return bip->infos + i;
+    return 0;
+  }
+
+  static block_info *add_block(uint64_t start, uint64_t size) {
+    for (block_info_page *bip = first_bi_page; bip; bip = bip->next)
+      for (int i = 0; i < 255; ++i)
+        if (bip->infos[i].size == 0) {
+          bip->infos[i].start = start;
+          bip->infos[i].size = size;
+          return bip->infos + i;
+        }
+    block_info_page *new_bip = (block_info_page *)_syscall_get_new_pages(1);
+    new_bip->infos[0].start = start;
+    new_bip->infos[0].size = size;
+    for (int i = 1; i < 255; ++i)
+      new_bip->infos[i].size = 0;
+    new_bip->next = first_bi_page;
+    first_bi_page = new_bip;
+    return new_bip->infos;
+  }
+
+  static block_info *find_minimal_block(uint64_t minimum_length) {
+    block_info *minimal_so_far = 0;
+    uint64_t length_so_far = UINT64_MAX;
+    for (block_info_page *bip = first_bi_page; bip; bip = bip->next)
+      for (int i = 0; i < 255; ++i)
+        if (bip->infos[i].size == minimum_length)
+          return bip->infos + i;
+        else if (
+          bip->infos[i].size > minimum_length &&
+          bip->infos[i].size < length_so_far
+        ) {
+          minimal_so_far = bip->infos + i;
+          length_so_far = bip->infos[i].size;
+        }
+    if (minimal_so_far != 0)
+      return minimal_so_far;
+    uint64_t pages_needed = (minimum_length - 1) / 4096 + 1;
+    void *block_start = _syscall_get_new_pages(pages_needed);
+    return add_block((uint64_t)block_start, pages_needed * 4096);
+  }
+
+  static void deallocate_aligned(uint64_t start, uint64_t length) {
+    block_info *buddy = try_find_block(start ^ length, length);
+    if (buddy) {
+      buddy->size = 0;
+      deallocate_aligned(start & ~length, length * 2);
+      return;
+    }
+    add_block(start, length);
+  }
+
+  static void deallocate(void *start, uint64_t length) {
+    uint64_t at = (uint64_t)start;
+    uint64_t left = length;
+    uint64_t i;
+    for (i = 1; i <= left; i *= 2)
+      if (at & i) {
+        deallocate_aligned(at, i);
+        at += i;
+        left -= i;
+      }
+    for (i /= 2; left > 0; i /= 2)
+      if (i <= left) {
+        deallocate_aligned(at, i);
+        at += i;
+        left -= i;
+      }
+  }
+
+  [[nodiscard]] static void *allocate(uint64_t length) {
+    block_info *bi = find_minimal_block(length);
+    void *to_return = (void *)bi->start;
+    void *new_start = (void *)(bi->start + length);
+    uint64_t new_length = bi->size - length;
+    bi->size = 0;
+    deallocate(new_start, new_length);
+    return to_return;
+  }
+
+  static void deallocate_with_length(void *start) {
+    uint64_t real_start = (uint64_t)start - 8;
+    deallocate((void *)real_start, *(uint64_t *)real_start);
+  }
+
+  [[nodiscard]] static void *allocate_with_length(uint64_t length) {
+    uint64_t *real_start = (uint64_t *)allocate(length + 8);
+    *real_start = length + 8;
+    return real_start + 1;
+  }
+
+}
+
+using namespace euler::allocator;
+
+void operator delete[](void *start) {
+  deallocate_with_length(start);
+}
+
+void operator delete(void *start) {
+  deallocate_with_length(start);
+}
+
+void operator delete[](void *start, uint64_t) {
+  deallocate_with_length(start);
+}
+
+void operator delete(void *start, uint64_t) {
+  deallocate_with_length(start);
+}
+
+void *operator new[](uint64_t size) {
+  return allocate_with_length(size);
+}
+
+void *operator new(uint64_t size) {
+  return allocate_with_length(size);
+}
diff --git a/libraries/euler/cassert.cpp b/libraries/euler/cassert.cpp
new file mode 100644
index 0000000..e811b38
--- /dev/null
+++ b/libraries/euler/cassert.cpp
@@ -0,0 +1,16 @@
+#include <cassert>
+
+namespace euler {
+
+  [[noreturn]] void assert_failed(
+    const char *, const char *, int, const char *
+  ) {
+    //TODO: print error and abort
+    //we could just exit right now but i want to keep us in
+    //the application so we can get a stack trace in gdb.
+    while (1)
+      ;
+  }
+
+
+}
diff --git a/libraries/euler/cctype.cpp b/libraries/euler/cctype.cpp
new file mode 100644
index 0000000..98234bb
--- /dev/null
+++ b/libraries/euler/cctype.cpp
@@ -0,0 +1,11 @@
+#include <cctype>
+
+namespace std {
+
+  int isspace(int ch) {
+    return
+      ch == ' ' || ch == '\n' || ch == '\t' ||
+      ch == '\r' || ch == '\v' || ch == '\f';
+  }
+
+}
diff --git a/libraries/euler/cstdio.cpp b/libraries/euler/cstdio.cpp
new file mode 100644
index 0000000..367e7e0
--- /dev/null
+++ b/libraries/euler/cstdio.cpp
@@ -0,0 +1,102 @@
+#include <euler/syscall.hpp>
+#include <cassert>
+#include <cstring>
+#include <cstdio>
+
+namespace euler {
+
+  //read-only with no error bits for now
+  struct file_t {
+
+    syscall::file_handle handle;
+
+    //TODO: variable size buffer? maybe a multiple of block size for device?
+    char buffer[1024];
+    //in bytes, aligned to buffer size; 1 for no buffer loaded
+    uint64_t buffer_start;
+
+    bool is_offset_in_buffer() {
+      return
+        buffer_start != 1 && offset >= buffer_start &&
+        offset < buffer_start + 1024;
+    }
+
+    syscall::file_result ensure_offset_in_buffer() {
+      if (is_offset_in_buffer())
+        return syscall::file_result::success;
+      uint64_t new_buffer_start = (offset / 1024) * 1024;
+      uint64_t new_buffer_end = new_buffer_start + 1024;
+      if (length < new_buffer_end)
+        new_buffer_end = length;
+      syscall::file_result result = _syscall_read_from_file(
+        handle, new_buffer_start, new_buffer_end - new_buffer_start, buffer);
+      if (result == syscall::file_result::success)
+        buffer_start = new_buffer_start;
+      return result;
+    }
+
+    uint64_t offset;
+    uint64_t length;
+
+  };
+
+}
+
+namespace std {
+
+  FILE *fopen(const char *path, const char *mode) {
+
+    assert(mode[0] == 'r' && mode[1] == '\0');
+
+    euler::syscall::file_handle handle;
+    euler::syscall::file_result result =
+      _syscall_open_file(path, strlen(path), handle);
+    if (result != euler::syscall::file_result::success)
+      return 0;
+
+    uint64_t length;
+    result = _syscall_get_file_length(handle, length);
+    if (result != euler::syscall::file_result::success) {
+      _syscall_close_file(handle);
+      return 0;
+    }
+
+    return new FILE {
+      .handle = handle,
+      .buffer = {},
+      .buffer_start = 1,
+      .offset = 0,
+      .length = length
+    };
+
+  }
+
+  int fclose(FILE *file) {
+    _syscall_close_file(file->handle);
+    delete file;
+    return 0;
+  }
+
+  int fgetc(FILE *from) {
+    if (from->offset >= from->length)
+      return EOF;
+    assert(
+      from->ensure_offset_in_buffer() == euler::syscall::file_result::success);
+    char ch = from->buffer[from->offset - from->buffer_start];
+    ++from->offset;
+    return ch;
+  }
+
+  int ungetc(int ch, FILE *from) {
+    if (ch == EOF || from->offset == 0)
+      return EOF;
+    --from->offset;
+    if (!from->is_offset_in_buffer()) {
+      ++from->offset;
+      return EOF;
+    }
+    from->buffer[from->offset - from->buffer_start] = ch;
+    return ch;
+  }
+
+}
diff --git a/libraries/euler/entry.cpp b/libraries/euler/entry.cpp
new file mode 100644
index 0000000..0bbffda
--- /dev/null
+++ b/libraries/euler/entry.cpp
@@ -0,0 +1,19 @@
+#include <euler/syscall.hpp>
+
+int main(int argc, char **argv);
+
+extern "C" [[noreturn]] void _entry() {
+
+  //TODO: static constructors
+
+  //TODO: get command line via system call and populate argc and argv.
+  int argc = 0;
+  char **argv = 0;
+
+  int result = main(argc, argv);
+
+  //TODO: static destructors
+
+  _syscall_end_this_process(result);
+
+}
diff --git a/libraries/euler/include/cassert b/libraries/euler/include/cassert
new file mode 100644
index 0000000..bc716a0
--- /dev/null
+++ b/libraries/euler/include/cassert
@@ -0,0 +1,13 @@
+#pragma once
+
+namespace euler {
+  [[noreturn]] void assert_failed(
+    const char *file, const char *function, int line, const char *condition);
+}
+
+#ifdef NDEBUG
+#define assert(condition) ((void)0)
+#else
+#define assert(condition) ((condition) ? ((void)0) : \
+  euler::assert_failed(__FILE__, __func__, __LINE__, #condition))
+#endif
diff --git a/libraries/euler/include/cctype b/libraries/euler/include/cctype
new file mode 100644
index 0000000..087b191
--- /dev/null
+++ b/libraries/euler/include/cctype
@@ -0,0 +1,7 @@
+#pragma once
+
+namespace std {
+
+  int isspace(int ch);
+
+}
diff --git a/libraries/euler/include/cstddef b/libraries/euler/include/cstddef
new file mode 120000
index 0000000..9eac9b6
--- /dev/null
+++ b/libraries/euler/include/cstddef
@@ -0,0 +1 @@
+../../../mintsuki-freestanding-headers/stddef.h
\ No newline at end of file
diff --git a/libraries/euler/include/cstdint b/libraries/euler/include/cstdint
new file mode 120000
index 0000000..b087235
--- /dev/null
+++ b/libraries/euler/include/cstdint
@@ -0,0 +1 @@
+../../../mintsuki-freestanding-headers/stdint.h
\ No newline at end of file
diff --git a/libraries/euler/include/cstdio b/libraries/euler/include/cstdio
new file mode 100644
index 0000000..3bb293b
--- /dev/null
+++ b/libraries/euler/include/cstdio
@@ -0,0 +1,19 @@
+#pragma once
+
+#define EOF (-1)
+
+namespace euler {
+  struct file_t;
+}
+
+namespace std {
+
+  typedef euler::file_t FILE;
+
+  FILE *fopen(const char *path, const char *mode);
+  int fclose(FILE *file);
+
+  int fgetc(FILE *from);
+  int ungetc(int ch, FILE *from);
+
+}
diff --git a/libraries/euler/include/cstring b/libraries/euler/include/cstring
new file mode 100644
index 0000000..65d00dc
--- /dev/null
+++ b/libraries/euler/include/cstring
@@ -0,0 +1,14 @@
+#pragma once
+
+#include <cstddef>
+
+namespace std {
+
+  static inline size_t strlen(const char *str) {
+    size_t i = 0;
+    while (str[i])
+      ++i;
+    return i;
+  }
+
+}
diff --git a/libraries/euler/include/euler/syscall.hpp b/libraries/euler/include/euler/syscall.hpp
new file mode 100644
index 0000000..781d444
--- /dev/null
+++ b/libraries/euler/include/euler/syscall.hpp
@@ -0,0 +1,48 @@
+#pragma once
+
+#include <cstdint>
+
+namespace euler::syscall {
+
+  typedef uint32_t encoded_color;
+  typedef int32_t exit_code;
+  typedef uint64_t file_handle;
+
+  enum [[nodiscard]] file_result : uint64_t {
+    success,
+    bad_file_handle,
+    device_error,
+    file_system_corrupt,
+    out_of_bounds,
+    does_not_exist,
+    directory
+  };
+
+}
+
+extern "C" {
+
+  euler::syscall::encoded_color _syscall_encode_color(
+    uint8_t red, uint8_t green, uint8_t blue);
+
+  void _syscall_get_framebuffer(
+    euler::syscall::encoded_color *&ptr_out, uint32_t &width_out,
+    uint32_t &height_out, uint32_t &pitch_out);
+
+  euler::syscall::file_result _syscall_open_file(
+    const char *path, uint64_t path_length, euler::syscall::file_handle &out);
+
+  euler::syscall::file_result _syscall_get_file_length(
+    euler::syscall::file_handle file, uint64_t &out);
+
+  euler::syscall::file_result _syscall_read_from_file(
+    euler::syscall::file_handle file,
+    uint64_t start_offset, uint64_t length, void *into);
+
+  [[noreturn]] void _syscall_end_this_process(euler::syscall::exit_code code);
+
+  [[nodiscard]] void *_syscall_get_new_pages(uint64_t count);
+
+  void _syscall_close_file(euler::syscall::file_handle file);
+
+}
diff --git a/libraries/euler/syscall.asm b/libraries/euler/syscall.asm
new file mode 100644
index 0000000..f7fe735
--- /dev/null
+++ b/libraries/euler/syscall.asm
@@ -0,0 +1,82 @@
+bits 64
+
+section .text
+
+global _syscall_encode_color
+_syscall_encode_color:
+  xor rax, rax
+  and edi, 0xff
+  and dx, 0xff
+  shl si, 8
+  shl edx, 16
+  or di, si
+  or edi, edx
+  syscall
+  ret
+
+global _syscall_get_framebuffer
+_syscall_get_framebuffer:
+  push rcx
+  push rdx
+  push rsi
+  push rdi
+  mov rax, 1
+  syscall
+  pop rcx
+  mov qword [rcx], rax
+  pop rcx
+  mov dword [rcx], edi
+  pop rcx
+  shr rdi, 32
+  mov dword [rcx], edi
+  pop rcx
+  mov dword [rcx], esi
+  ret
+
+global _syscall_open_file
+_syscall_open_file:
+  mov rax, 2
+  push rdx
+  syscall
+  pop rdx
+  mov qword [rdx], rdi
+  ret
+
+global _syscall_get_file_length
+_syscall_get_file_length:
+  mov rax, 3
+  push rsi
+  syscall
+  pop rsi
+  mov qword [rsi], rdi
+  ret
+
+global _syscall_read_from_file
+_syscall_read_from_file:
+  mov rax, 4
+  push rcx
+  push rdx
+  push rsi
+  push rdi
+  mov rdi, rsp
+  syscall
+  add rsp, 32
+  ret
+
+global _syscall_end_this_process
+_syscall_end_this_process:
+  mov rax, 5
+  syscall
+  ;does not return
+
+global _syscall_get_new_pages
+_syscall_get_new_pages:
+  mov rax, 6
+  syscall
+  ret
+
+global _syscall_close_file
+_syscall_close_file:
+  mov rax, 7
+  syscall
+  ret