Merge pull request 'Zone Freeing - No Fragmentation' (#12) from zone/real-free into main

Reviewed-on: #12

quantum/src/memory/zone.c

@@ -4,13 +4,20 @@
 
 #include "../defines.h"
 #include "../logger/logger.h"
+#include "../types/linked_list.h"
 #include "zone.h"
 
 typedef struct ZoneHeader {
   u64 capacity;
   u64 cur_size;
+  List *free_zones;
 } ZoneHeader;
 
+typedef struct FreeZone {
+  void *start_address;
+  u64 capacity;
+} FreeZone;
+
 Zone *zoneCreate(size_t sizeBytes) {
   // First we need to get a block of memory from the OS
   // This block needs to include the size of what we want to store
@@ -25,6 +32,7 @@ Zone *zoneCreate(size_t sizeBytes) {
   // Initialize the values of the header
   zone_header->capacity = sizeBytes;
   zone_header->cur_size = 0;
+  zone_header->free_zones = listCreate();
 
   return zone_addr;
 }
@@ -32,6 +40,29 @@ Zone *zoneCreate(size_t sizeBytes) {
 void *zoneAlloc(Zone *zone, size_t sizeBytes) {
   ZoneHeader *zone_header = (ZoneHeader *)zone - sizeof(ZoneHeader);
 
+  u64 cur_free_zones = listSize(zone_header->free_zones);
+
+  if (cur_free_zones > 0) {
+    for (u64 i = 1; i <= cur_free_zones; i++) {
+      FreeZone *curFreeZone =
+          (FreeZone *)listDataAt(zone_header->free_zones, i);
+
+      u64 freeZoneSize = curFreeZone->capacity;
+      if (freeZoneSize >= sizeBytes) {
+        void *ret_addr = curFreeZone->start_address;
+        curFreeZone->start_address += sizeBytes;
+        curFreeZone->capacity -= sizeBytes;
+
+        if (curFreeZone->capacity <= 0) {
+          listRemoveAt(zone_header->free_zones, i);
+          free(curFreeZone);
+        }
+
+        return ret_addr;
+      }
+    }
+  }
+
   if (zone_header->cur_size + sizeBytes > zone_header->capacity) {
     QERROR("Could not allocate, not enough space.");
     return NULL;
@@ -41,17 +72,10 @@ void *zoneAlloc(Zone *zone, size_t sizeBytes) {
 
   zone_header->cur_size += sizeBytes;
 
-  printf("Zone Header Information:\n");
-  printf("Current Size: %" PRIu64 "\n", zone_header->cur_size);
-  printf("Total Capacity: %" PRIu64 "\n", zone_header->capacity);
-
   return new_mem;
 }
 
-void zoneFree(void *data, size_t dataSize) {
+void zoneFree(void *data, Zone *zone, size_t dataSize) {
-  // TODO: We want to eventually pass in a pointer to the zone so we can track
-  // our free blocks
-
   // Lets first check to make sure we weren't given a NULL pointer
   if (data == NULL)
     return;
@@ -60,26 +84,31 @@ void zoneFree(void *data, size_t dataSize) {
   // to 0
   memset(data, 0, dataSize);
 
+  FreeZone *newFreeZone = malloc(sizeof(FreeZone));
+  ZoneHeader *zone_header = (ZoneHeader *)zone - sizeof(ZoneHeader);
+
+  newFreeZone->start_address = data;
+  newFreeZone->capacity = dataSize;
+
+  listPush(zone_header->free_zones, newFreeZone);
+
   // Now we need to null the pointer
   data = NULL;
-
-  // TODO: Add logic to alert that this space can now be used
 }
 
 void zoneClear(Zone *zone) {
   ZoneHeader *zone_header = (ZoneHeader *)zone - sizeof(ZoneHeader);
 
   zone_header->cur_size = 0;
-
-  printf("Zone Header Information:\n");
-  printf("Current Size: %" PRIu64 "\n", zone_header->cur_size);
-  printf("Total Capacity: %" PRIu64 "\n", zone_header->capacity);
 }
 
 void zoneDestroy(Zone *zone) {
   // First we need to go back to the beginning of the header as we returned
   // an offset for the user to use
-  void *del_mem = (ZoneHeader *)zone - sizeof(ZoneHeader);
+  ZoneHeader *del_mem = (ZoneHeader *)zone - sizeof(ZoneHeader);
+
+  // Next we need to destory our free_zones list
+  listDestroy(del_mem->free_zones);
 
   // Free the memory
   free(del_mem);

quantum/src/memory/zone.h

@@ -2,10 +2,10 @@
 
 #include <stddef.h> // size_t definition
 
-typedef struct _Zone Zone;
+typedef struct Zone Zone;
 
 Zone *zoneCreate(size_t sizeBytes);
 void *zoneAlloc(Zone *zone, size_t sizeBytes);
-void zoneFree(void *data, size_t dataSize);
+void zoneFree(void *data, Zone *zone, size_t dataSize);
 void zoneClear(Zone *zone);
 void zoneDestroy(Zone *zone);

quantum/src/types/linked_list.c

@@ -12,12 +12,18 @@ typedef struct Node {
   void *data;
 } Node;
 
-List listCreate() {
+typedef struct List {
-  List new_list;
+  Node *cur_head;
+  Node *cur_tail;
+  u64 cur_size;
+} List;
 
-  new_list.cur_size = 0;
+List *listCreate() {
-  new_list.cur_head = NULL;
+  List *new_list = malloc(sizeof(List));
-  new_list.cur_tail = NULL;
+
+  new_list->cur_size = 0;
+  new_list->cur_head = NULL;
+  new_list->cur_tail = NULL;
 
   return new_list;
 }
@@ -29,34 +35,26 @@ void listDestroy(List *list) {
     return;
   }
 
-  u64 list_size = list->cur_size;
   Node *del_node = list->cur_tail;
-  Node *next_node = list->cur_tail->prev;
+  Node *next_node;
 
-  while (list_size > 0) {
+  while (del_node != NULL) {
-    // First we want to free del_node
+    // We want to set del_node to the next_node to free
+    next_node = del_node->prev;
+
+    // Then we want to free del_node
     free(del_node);
 
-    // Now we want to set del_node to the next_node to free
+    // Finally we want to set del_node to the next_node to free
     del_node = next_node;
-
-    // Now we set next_node equal to the del_node's previous node
-    if (next_node->prev != NULL) {
-      next_node = next_node->prev;
-    } else if (next_node->prev == NULL) {
-      next_node->next = NULL;
-    }
-
-    // Now we decrement list_size
-    list_size--;
   }
 
   // Now we null out the cur_head and cur_tail of our list
   list->cur_tail = NULL;
   list->cur_head = NULL;
 
-  // Now we null out the list and make it point to nothing
+  // Now we free out the list and make it point to nothing
-  list = NULL;
+  free(list);
 }
 
 u64 listSize(const List *list) {
@@ -244,6 +242,16 @@ void listInsertAt(List *list, u64 pos, void *data) {
     return;
   }
 
+  // Make sure we passed in a valid position
+  if (pos < 1 || pos > list->cur_size) {
+    // If we have elements in the list
+    if (list->cur_size != 0) {
+      // Then the position is actually out of bounds, so return.
+      QERROR("Position given is out of range: %" PRId64, pos);
+      return;
+    }
+  }
+
   u64 counter = 1;
   Node *insert_pos;
   Node *prev_node;

quantum/src/types/linked_list.h

@@ -2,15 +2,9 @@
 
 #include "../defines.h"
 
-typedef struct Node Node;
+typedef struct List List;
 
-typedef struct List {
+List *listCreate();
-  Node *cur_head;
-  Node *cur_tail;
-  u64 cur_size;
-} List;
-
-List listCreate();
 void listDestroy(List *list);
 u64 listSize(const List *list);
 void *listPeek(List *list);

test_stuff/src/main.c

@@ -1,4 +1,3 @@
-#include "types/linked_list.h"
 #include <defines.h>
 #include <logger/logger.h>
 #include <memory/zone.h>
@@ -13,48 +12,24 @@ int main() {
   QINFO("Size of f32: %lu", sizeof(f32));
   QINFO("Size of f64: %lu", sizeof(f64));
 
-  QINFO("Creating a List...");
+  Zone *test_zone = zoneCreate(4096);
-  List my_list = listCreate();
-  QINFO("Pushing to my_list...")
-  i32 pushVal = 42;
-  listPush(&my_list, &pushVal);
-  i32 peekVal = *(i32 *)listPeek(&my_list);
 
-  QDEBUG("Peeking value off of my_list: %" PRId32, peekVal);
+  u64 val1 = 420;
+  u32 val2 = 169;
+  u32 val3 = 80085;
 
-  QINFO("Pushing another number to my_list...");
+  u64 *zVal1 = (u64 *)zoneAlloc(test_zone, sizeof(val1));
-  i32 pushVal2 = 169420;
+  *zVal1 = val1;
-  listPush(&my_list, &pushVal2);
-  peekVal = *(i32 *)listPeek(&my_list);
 
-  QDEBUG("Peeking value off of my_list: %" PRId32, peekVal);
+  zoneFree(zVal1, test_zone, sizeof(zVal1));
 
-  i32 pushVal3 = 69;
+  u32 *zVal2 = (u32 *)zoneAlloc(test_zone, sizeof(val2));
-  listPush(&my_list, &pushVal3);
+  u32 *zVal3 = (u32 *)zoneAlloc(test_zone, sizeof(val3));
-  QDEBUG("Peeking a 3rd value off of my_list: %" PRId32, peekVal);
 
-  i32 popVal = *(i32 *)listPop(&my_list);
+  *zVal2 = val2;
-  QDEBUG("Popped a value off of my_list: %" PRId32, popVal);
+  *zVal3 = val3;
 
-  peekVal = *(i32 *)listPeek(&my_list);
+  void *dont_care = zoneAlloc(test_zone, 64);
-
-  QDEBUG("Peeking value off of my_list: %" PRId32, peekVal);
-
-  i32 insertValue = 80085;
-
-  QINFO("Inserting a value at position 2.");
-  listInsertAt(&my_list, 2, &insertValue);
-
-  QDEBUG("Data at position 2 is: %" PRId32, *(i32 *)listDataAt(&my_list, 2));
-
-  QINFO("Removing a value at position 2.");
-  listRemoveAt(&my_list, 2);
-
-  QDEBUG("Data at position 2 is now: %" PRId32,
-         *(i32 *)listDataAt(&my_list, 2));
-
-  QINFO("Destorying List...");
-  listDestroy(&my_list);
 
   return 0;
 }