fixed wrong bump allocator init

c_os/kernel/Allocator.cc

@@ -17,13 +17,13 @@
  *                  setup.asm                                                *
  *                      0x1000: System-Code (max. 512K) geladen              *
  *                  System-Code                                              *
- *                    0x100000:	System-Code, kopiert nach Umschalten in      *
+ *                    0x100000: System-Code, kopiert nach Umschalten in      *
  *                              den Protected Mode kopiert (GRUB kann nur    *
  *                              an Adressen >1M laden)                       *
  *           Globale Variablen: Direkt nach dem Code liegen die globalen     *
  *                              Variablen.                                   *
  *                        Heap:                                              *
- *                    0x300000:	Start-Adresse der Heap-Verwaltung            *
+ *                    0x300000: Start-Adresse der Heap-Verwaltung            *
  *                    0x400000: Letzte Adresse des Heaps                     *
  *                                                                           *
  * Achtung:         Benötigt einen PC mit mindestens 8 MB RAM!               *
@@ -31,53 +31,51 @@
  * Autor:           Michael Schoettner, HHU, 1.3.2022                        *
  *****************************************************************************/
 
-#include <stddef.h>
-#include "kernel/Globals.h"
 #include "kernel/Allocator.h"
+#include "kernel/Globals.h"
+#include <stddef.h>
 
+#define MEM_SIZE_DEF 8 * 1024 * 1024  // Groesse des Speichers = 8 MB
 
-#define MEM_SIZE_DEF        	 8*1024*102 // Groesse des Speichers = 8 MB
-
-#define HEAP_START           	 0x300000 	// Startadresse des Heaps
-#define HEAP_SIZE	        	 1024*1024 	// Default-Groesse des Heaps, falls 
-											// nicht über das BIOS ermittelbar 
+#define HEAP_START 0x300000    // Startadresse des Heaps
+#define HEAP_SIZE 1024 * 1024  // Default-Groesse des Heaps, falls \
+                               // nicht über das BIOS ermittelbar
 
 /*****************************************************************************
  * Konstruktor:     Allocator::Allocator                                     *
  *****************************************************************************/
 Allocator::Allocator() {
-   // Groesse des Hauptspeichers (kann über das BIOS abgefragt werden,
-   // aber sehr umstaendlich, daher hier fest eingetragen
-   total_mem = MEM_SIZE_DEF;
+    // Groesse des Hauptspeichers (kann über das BIOS abgefragt werden,
+    // aber sehr umstaendlich, daher hier fest eingetragen
+    total_mem = MEM_SIZE_DEF;
 
-   heap_start = HEAP_START;
-   heap_end   = HEAP_START + HEAP_SIZE;
-   heap_size  = HEAP_SIZE;
-   
-   initialized = 1;
+    heap_start = HEAP_START;
+    heap_end = HEAP_START + HEAP_SIZE;
+    heap_size = HEAP_SIZE;
+
+    initialized = 1;
 }
 
-
 /*****************************************************************************
  * Nachfolgend sind die Operatoren von C++, die wir hier ueberschreiben      *
  * und entsprechend 'mm_alloc' und 'mm_free' aufrufen.                       *
  *****************************************************************************/
-void* operator new ( size_t size ) {
-     return allocator.alloc(size);
+void* operator new(size_t size) {
+    return allocator.alloc(size);
 }
 
-void* operator new[]( size_t count ) {
+void* operator new[](size_t count) {
     return allocator.alloc(count);
 }
 
-void operator delete ( void* ptr )  {
-    allocator.free(ptr);
-}
- 
-void operator delete[] ( void* ptr ) {
+void operator delete(void* ptr) {
     allocator.free(ptr);
 }
 
-void operator delete(void*ptr, unsigned int sz) {
+void operator delete[](void* ptr) {
+    allocator.free(ptr);
+}
+
+void operator delete(void* ptr, unsigned int sz) {
     allocator.free(ptr);
 }

c_os/kernel/allocator/BumpAllocator.cc

@@ -22,13 +22,12 @@ void BumpAllocator::init() {
 
     /* Hier muess Code eingefuegt werden */
 
-    this->heap_start = 3 * 1024 * 1024;                   // 3 MB
-    this->heap_size = 1 * 1024 * 1024;                    // 1 MB
-    this->heap_end = this->heap_start + this->heap_size;  // 4 MB
     this->allocations = 0;
     this->next = (unsigned char*)heap_start;
 
-    this->initialized = true;
+    kout << "Initialized Bump Allocator" << endl
+         << "Heap Start: " << hex << this->heap_start << ", Heap End: " << this->heap_end << endl;
+    kout << endl;
 }
 
 /*****************************************************************************
@@ -39,9 +38,10 @@ void BumpAllocator::init() {
 void BumpAllocator::dump_free_memory() {
 
     /* Hier muess Code eingefuegt werden */
+
     kout << "Freier Speicher:" << endl
-         << "    Heap Start: " << this->heap_start << ", Heap End: " << this->heap_end << endl
-         << "    Next: " << this->next << ", Allocations: " << this->allocations << endl;
+         << "Next: " << hex << this->next << ", Allocations: " << dec << this->allocations << endl;
+    kout << endl;
 }
 
 /*****************************************************************************
@@ -53,13 +53,11 @@ void* BumpAllocator::alloc(unsigned int req_size) {
 
     /* Hier muess Code eingefuegt werden */
 
-    if (!this->initialized) {
-        kout << "Allocator not initialized :(" << endl;
-        return NULL;
-    }
+    kout << "Requested " << dec << req_size << " Bytes" << endl;
 
     if (req_size > this->heap_end - (unsigned int)this->next) {
         kout << "More memory requested than available :(" << endl;
+        kout << endl;
         return NULL;
     }
 
@@ -67,6 +65,9 @@ void* BumpAllocator::alloc(unsigned int req_size) {
     this->next = this->next + req_size;
     this->allocations = this->allocations + 1;
 
+    kout << "Allocated " << dec << req_size << " Bytes." << endl;
+    kout << endl;
+
     return allocated;
 }
 

c_os/kernel/allocator/BumpAllocator.h

@@ -23,7 +23,7 @@ private:
     BumpAllocator(Allocator& copy);  // Verhindere Kopieren
 
 public:
-    BumpAllocator() {}
+    BumpAllocator() {};  // Allocator() called implicitely in C++
 
     void init();
     void dump_free_memory();

c_os/kernel/allocator/LinkedListAllocator.cc

@@ -9,12 +9,11 @@
  * Autor:           Michael Schoettner, HHU, 13.6.2020                        *
  *****************************************************************************/
 
-#include <stddef.h>
-#include "kernel/Globals.h"
 #include "kernel/allocator/LinkedListAllocator.h"
+#include "kernel/Globals.h"
+#include <stddef.h>
 
-#define HEAP_MIN_FREE_BLOCK_SIZE 64         // min. Groesse eines freien Blocks
-
+#define HEAP_MIN_FREE_BLOCK_SIZE 64  // min. Groesse eines freien Blocks
 
 /*****************************************************************************
  * Methode:         LinkedListAllocator::init                                *
@@ -28,11 +27,9 @@
  *****************************************************************************/
 void LinkedListAllocator::init() {
 
-     /* Hier muess Code eingefuegt werden */
-
+    /* Hier muess Code eingefuegt werden */
 }
 
-
 /*****************************************************************************
  * Methode:         LinkedListAllocator::dump_free_memory                    *
  *---------------------------------------------------------------------------*
@@ -40,31 +37,25 @@ void LinkedListAllocator::init() {
  *****************************************************************************/
 void LinkedListAllocator::dump_free_memory() {
 
-     /* Hier muess Code eingefuegt werden */
-
+    /* Hier muess Code eingefuegt werden */
 }
 
-
 /*****************************************************************************
  * Methode:         LinkedListAllocator::alloc                               *
  *---------------------------------------------------------------------------*
  * Beschreibung:    Einen neuen Speicherblock allozieren.                    * 
  *****************************************************************************/
-void * LinkedListAllocator::alloc(unsigned int req_size) {
-
-     /* Hier muess Code eingefuegt werden */
+void* LinkedListAllocator::alloc(unsigned int req_size) {
 
+    /* Hier muess Code eingefuegt werden */
 }
 
-
 /*****************************************************************************
  * Methode:         LinkedListAllocator::free                                *
  *---------------------------------------------------------------------------*
  * Beschreibung:    Einen Speicherblock freigeben.                           *
  *****************************************************************************/
-void LinkedListAllocator::free(void *ptr) {
-
-     /* Hier muess Code eingefuegt werden */
+void LinkedListAllocator::free(void* ptr) {
 
+    /* Hier muess Code eingefuegt werden */
 }
-

c_os/kernel/allocator/LinkedListAllocator.h

@@ -14,30 +14,27 @@
 
 #include "kernel/Allocator.h"
 
-
 // Format eines freien Blocks
 struct free_block {
     unsigned int size;
-    struct free_block *next;
+    struct free_block* next;
 };
 
-
 class LinkedListAllocator : Allocator {
-    
-private:
-      // freie Bloecke werden verkettet
-      struct free_block *free_start;
 
-      LinkedListAllocator(Allocator &copy); // Verhindere Kopieren
+private:
+    // freie Bloecke werden verkettet
+    struct free_block* free_start;
+
+    LinkedListAllocator(Allocator& copy);  // Verhindere Kopieren
 
 public:
-      LinkedListAllocator () { }
-
-      void init ();        
-      void dump_free_memory ();
-      void* alloc (unsigned int req_size);
-      void free (void *ptr);
+    LinkedListAllocator() {}
 
+    void init();
+    void dump_free_memory();
+    void* alloc(unsigned int req_size);
+    void free(void* ptr);
 };
 
 #endif

c_os/main.cc

@@ -15,13 +15,11 @@
 #include "user/HeapDemo.h"
 
 int main() {
+    kout.clear();
 
     // Speicherverwaltung initialisieren
     allocator.init();
 
-    // Bildschirm loeschen.
-    kout.clear();
-
     // text_demo();
     // sound_demo();
     // keyboard_demo();

c_os/user/HeapDemo.cc

@@ -34,4 +34,7 @@ void heap_demo() {
 
     MyObj* b = new MyObj(10);
     allocator.dump_free_memory();
+
+    allocator.alloc(1024 * 1024);  // should fail as only 1024 * 1024 - (4 + 4) bytes remain
+    allocator.dump_free_memory();
 }