Adds linker script, C++ support and a simple screen class.

prototypes/base/Makefile

@@ -1,21 +1,24 @@
 
-AS=clang
-CC=clang
-CXX=clang++
+AS=gcc
+CC=gcc
+CXX=g++
 LD=ld
 
-FLAGS = -ffreestanding -m32
+FLAGS = -ffreestanding -m32 -Wall -iquote include
 ASFLAGS = $(FLAGS)
 CFLAGS = $(FLAGS)	
-CXXFLAGS = $(FLAGS)
+CXXFLAGS = $(FLAGS) -std=c++14 -fno-rtti -fno-exceptions -fno-leading-underscore -fno-use-cxa-atexit -nostdlib -fno-builtin
 
-SRCS = $(shell find -name '*.[cS]')
+SRCS = $(shell find -regextype egrep -regex '.*/.*\.(cpp|S|c)')
 OBJS = $(addsuffix .o, $(notdir $(basename $(SRCS))))
 
 all: kernel-base.ker
 
 kernel-base.ker: $(OBJS)
-	$(LD) -melf_i386 -Ttext=0x1000000 -o kernel-base.ker $(addprefix obj/, $^)
+	$(LD) -melf_i386 -Tlinker.ld -o kernel-base.ker $(addprefix obj/, $^)
+
+%.o: %.cpp
+	$(CXX) $(CXXFLAGS) -c -o obj/$@ $<
   
 %.o: %.c
 	$(CC) $(ASFLAGS) -c -o obj/$@ $<
@@ -23,5 +26,16 @@ kernel-base.ker: $(OBJS)
 %.o: %.S
 	$(AS) $(CFLAGS) -c -o obj/$@ $<
 	
-%.o: %.cpp
-	$(CPP) $(CXXFLAGS) -c -o obj/$@ $<
+%.o: src/%.cpp
+	$(CXX) $(CXXFLAGS) -c -o obj/$@ $<
+  
+%.o: src/%.c
+	$(CC) $(ASFLAGS) -c -o obj/$@ $<
+  
+%.o: src/%.S
+	$(AS) $(CFLAGS) -c -o obj/$@ $<
+
+run:
+	qemu-system-i386 -kernel kernel-base.ker
+
+bnr: kernel-base.ker run

prototypes/base/entrypoint.S

@@ -1,30 +1,22 @@
 .section .text
  
-// Init ist eine Funktion aus init.c
 .extern init
+.extern compat_call_ctors
+.extern compat_call_dtors
 
-// _start muss global sein, damit der Linker es findet und als Einsprungspunkt
-// benutzen kann (alle Labels, die nicht global sind, sind nur in dieser Datei
-// sichtbar)
 .global _start
 _start:
-    // Stack initialisieren
-    mov $kernel_stack, %esp
+  mov $kernel_stack, %esp
  
-    // C-Code aufrufen
-    call init
+  call compat_call_ctors
+  call init
+  call compat_call_dtors
 
-    // Falls wir jemals aus init zurueckkommen sollten, sperren wir die Interrupts und
-    // halten einfach den Prozessor an. (man braucht ihn ja nicht unnötig heißlaufen lassen.)
 _stop:
-    cli
-    hlt
+  cli
+  hlt
+  jmp _stop
     
-    // Sollte es doch weitergehen, probieren wir erneut die CPU schlafen zu lassen
-    jmp _stop
- 
-// 8 kB Stack fuer den Kernel. Das Label steht hinter dem freien Speicher,
-// weil der Stack nach unten waechst
 .section .bss
 .space 8192
 kernel_stack:

prototypes/base/include/compat.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+void compat_call_ctors();
+
+void compat_call_dtors();
+
+#if defined(__cplusplus)
+}
+#endif

prototypes/base/include/screen.hpp

@@ -0,0 +1,63 @@
+#pragma once
+
+#include <inttypes.h>
+
+enum class Color : uint8_t
+{
+  Black = 0,
+  Blue = 1,
+  Green = 2,
+  Cyan = 3,
+  Red = 4,
+  Magenta = 5,
+  Brown = 6,
+  LightGray = 7,
+  Gray = 8,
+  LightBlue = 9,
+  LightGreen = 10,
+  LightCyan = 11,
+  LightRed = 12,
+  LightMagenta = 13,
+  Yellow = 14,
+  White = 15,
+};
+
+using ColorInteger = uint8_t;
+
+struct ScreenChar
+{
+  char c;
+  struct {
+    ColorInteger fg : 4;
+    ColorInteger bg : 4;
+  };
+};
+
+class Screen
+{
+private:
+  static ScreenChar outOfScreen;
+private:
+  ScreenChar * const buffer;
+  const int width;
+  const int height;
+public:
+  static Screen main;
+public:
+  Screen(ScreenChar *buffer, int width, int height);
+  
+  void clear();
+  
+  ScreenChar & operator ()(int x, int y) {
+    if(x < 0 || y < 0 || x >= this->width || y >= this->height) {
+      // return Screen::outOfScreen;
+    }
+    return this->buffer[this->width * y + x];
+  }
+  ScreenChar const & operator ()(int x, int y) const {
+    if(x < 0 || y < 0 || x >= this->width || y >= this->height) {
+      return Screen::outOfScreen;
+    }
+    return this->buffer[this->width * y + x];
+  }
+};

prototypes/base/init.c

@@ -1,16 +0,0 @@
-void init(void)
-{
-    const char hw[] = "Hello World!";
-    int i;
-    char* video = (char*) 0xb8000;
- 
-    // C-Strings haben ein Nullbyte als Abschluss
-    for (i = 0; hw[i] != '\0'; i++) {
- 
-        // Zeichen i in den Videospeicher kopieren
-        video[i * 2] = hw[i];
- 
-        // 0x07 = Hellgrau auf Schwarz
-        video[i * 2 + 1] = 0x07;
-    }
-}

prototypes/base/init.cpp

@@ -0,0 +1,21 @@
+#include <inttypes.h>
+
+#include "screen.hpp"
+#include "compat.h"
+
+extern "C" void init(void)
+{
+  const char hw[] = "Hello World!";
+  int i;
+
+  // C-Strings haben ein Nullbyte als Abschluss
+  for (i = 0; hw[i] != '\0'; i++) {
+
+    // Zeichen i in den Videospeicher kopieren
+    Screen::main(i,0).c = hw[i];
+
+    // 0x07 = Hellgrau auf Schwarz
+    Screen::main(i,0).fg = (int)Color::Black;
+    Screen::main(i,0).bg = (int)Color::LightRed;
+  }
+}

prototypes/base/linker.ld

@@ -0,0 +1,37 @@
+ENTRY(_start)
+OUTPUT_FORMAT(elf32-i386)
+OUTPUT_ARCH(i386:i386)
+
+SECTIONS
+{
+    . = 0x100000;
+
+    kernelStart = .;
+
+    .text : {
+        *(multiboot)
+        *(.text)
+    }
+    .data ALIGN(4096) : {
+        start_ctors = .;
+        KEEP(*( .init_array ));
+        KEEP(*(SORT_BY_INIT_PRIORITY( .init_array.* )));
+        end_ctors = .;
+
+        start_dtors = .;
+        KEEP(*( .fini_array ));
+        end_dtors = .;
+
+        *(.data)
+    }
+    .rodata ALIGN(4096) : {
+        *(.rodata)
+    }
+    .bss ALIGN(4096) : {
+        *(.bss)
+    }
+
+    /* Align the end of the kernel to the page size */
+    . = ALIGN(4096);
+    kernelEnd = .;
+}

prototypes/base/multiboot.S

@@ -1,4 +1,4 @@
-.section .text
+.section multiboot
  
 #define MB_MAGIC 0x1badb002
 #define MB_FLAGS 0x0

prototypes/base/src/compat.c

@@ -0,0 +1,17 @@
+#include "compat.h"
+
+typedef void (*constructor)();
+ 
+constructor start_ctors;
+constructor end_ctors;
+
+void compat_call_ctors()
+{
+  for (constructor* i = &start_ctors;i != &end_ctors;++i)
+    (*i)();
+}
+
+void compat_call_dtors()
+{
+
+}

prototypes/base/src/screen.cpp

@@ -0,0 +1,19 @@
+#include <inttypes.h>
+#include "screen.hpp"
+
+ScreenChar Screen::outOfScreen;
+Screen Screen::main((ScreenChar*)0xb8000, 80, 25);
+
+Screen::Screen(ScreenChar *buffer, int width, int height) : 
+  buffer(buffer),
+  width(width),
+  height(height)
+{
+  this->clear();
+}
+  
+void Screen::clear() {
+  for(int i = 0; i < this->width * this->height; i++) {
+    this->buffer[i].c = ' ';
+  }
+}