correct malloc

programs/lib/malloc.c

@@ -2,13 +2,13 @@
 
 malloc_header_t *first_block;
 
-void init_malloc() { //TODO rm
+void init_malloc() {
     first_block = NULL;
+    malloc(0);
 }
 
 void *expand_heap(int size) {
     void *h = resize_heap(size);
-    printf("New heap pointer: %x\n", h);
     return h;
 }
 
@@ -27,20 +27,21 @@ void *malloc(u32 size) {
             new_block->size = size;
             block->next_block->prev_block = new_block;
             block->next_block = new_block;
-            //printf("found gap of size %x at %x\n", size, new_block);
             return (void *) new_block + sizeof(malloc_header_t);
         }
         prev_block = block;
     }
     malloc_header_t *new_block = (malloc_header_t *) expand_heap(size);
-    //printf("new block of size %x at %x\n", size, new_block);
     if(!new_block) return NULL;
     new_block->size = size;
     new_block->next_block = NULL;
     if(prev_block) {
         prev_block->next_block = new_block;
         new_block->prev_block = prev_block;
-        //TODO CHECK prev_block + prev_block->size = new_block
+        if((void*) prev_block + prev_block->size != (void*) new_block) {
+            printf("Corrupted malloc\n");
+            return NULL;
+        }
     } else {
         new_block->prev_block = NULL;
         first_block = new_block;
@@ -49,16 +50,16 @@ void *malloc(u32 size) {
 }
 
 void free(void *allocated) {
-    //printf("free %x\n", allocated);
     malloc_header_t *block = (malloc_header_t*) allocated - 1;
     if(block->prev_block) {
         block->prev_block->next_block = block->next_block;
         if(block->next_block)
             block->next_block->prev_block = block->prev_block;
         else {
-            shrink_heap(block->size);
+            shrink_heap((u32) block + block->size - (u32) block->prev_block - block->prev_block->size);
         }
     } else {
+        printf("free first block...\n");
         shrink_heap(block->size);
         first_block = NULL;
     }

programs/lib/malloc.h

@@ -13,4 +13,5 @@ struct malloc_header {
 
 void *malloc(u32 size);
 void free(void *allocated);
+void init_malloc();
 #endif

programs/src/malloc_test/main.c

@@ -2,17 +2,6 @@
 
 int main() {
     printf("Hello!\n");
-    /*
-    if(!resize_heap(0x50000)) {
-        printf("resize fail\n");
-        exit(-1);
-    }
-    printf("PRE %x - %x\n", *((u32 *) 0x88008C04), *((u32 *) 0x88040BFB + 2));
-    *((u32 *) 0x88008C04) = 0x1337;
-    printf("PS* %x - %x\n", *((u32 *) 0x88008C04), *((u32 *) 0x88040BFB + 2));
-    
-    return 0;
-    //*/
     init_malloc();
     u32 *x = (u32*) malloc(sizeof(u32));
     *x = 0xFEE;
@@ -30,25 +19,19 @@ int main() {
     printf("z = %x, *z = %x\n", z, *z);
 
     u32 n = 0x80;
-    u32 m = 0x1005;
+    u32 m = 0x1800;
     void ** pointers = (void **) malloc(n * sizeof(void **));
     for(int i = 0; i < n; i ++) pointers[i] = NULL;
     for(u32 ct = 0; ct < 0x1000; ct++) {
-        print = ct >= 0x820;
-        print = 0;
-        if(print) {
-            printf("# %x #\n", ct);
-            malloc_header_t *b = (malloc_header_t*) 0x88040BFB;
-            printf("BAD GUY: %x %x %x\n", b, b->prev_block, b->next_block);
-        }
         int i = rand() % n;
         if(pointers[i]) free(pointers[i]);
-        if(print) {
-            malloc_header_t *b = (malloc_header_t*) 0x88040BFB;
-            printf("BAD GUY: %x %x %x\n", b, b->prev_block, b->next_block);
-        }
         pointers[i] = malloc(rand() % m);
         flush(STDOUT);
-        if(!pointers[i]) break;
+        if(!pointers[i]) {
+            printf("fail\n");
+            exit(-1);
+        }
     }
+
+    printf("success\n");
 }