Update

Lab4/Makefile

@@ -0,0 +1,8 @@
+all:	main.o ex1.o
+	gcc main.o ex1.o -o ex1 -lm
+main.o:	main.c ex1.h
+	gcc -c main.c
+ex1.o:	ex1.c ex1.h
+	gcc -c ex1.c
+clean:
+	rm -f *.o ex1

Lab4/ex1.c

@@ -0,0 +1,94 @@
+#include "ex1.h"
+
+/* Tim block trong dau tien co size thich hop */
+blk *find_fit(unsigned int size)
+{
+    blk *cur = head;
+    while (cur != NULL)
+    {
+        if (cur->is_free == 1 && cur->size >= size)
+            break;
+        cur = cur->next;
+    }
+    return cur;
+}
+
+void *aligned_malloc(unsigned int size, unsigned int align)
+{
+    if (size == 0)
+        return NULL;
+    /* Kiem tra align la so mu cua 2 */
+    if (IS_POWER_OF_2(align) == 0)
+        return NULL;
+    /* Tong gia tri do lon cua block can xin */
+    unsigned int total_size = size + align - 1 + sizeof(blk) + sizeof(blk *);
+    /* Tim block trong thich hop (neu co) */
+    blk *blk_head = find_fit(total_size);
+    void *ret;
+    if (blk_head != NULL)
+    {
+        /* Gan gia tri "da duoc dung" */
+        blk_head->is_free = 0;
+        /* Tim vi tri tra ve thich hop */
+        ret = (void *)(ALIGN(blk_head + sizeof(blk) + sizeof(blk *), align));
+        /* Luu con tro den vi tri giu thong tin cua block */
+        *(blk **)((size_t)ret - sizeof(blk *)) = blk_head;
+        return ret;
+    }
+    void *block = sbrk(total_size);
+    if (block == (void *)-1)
+        return NULL;
+    /* Vi tri luu thong tin cua block */
+    blk_head = block;
+    blk_head->size = total_size;
+    blk_head->is_free = 0;
+    blk_head->next = NULL;
+    if (head == NULL)
+        head = blk_head;
+    if (tail != NULL)
+        tail->next = blk_head;
+    tail = blk_head;
+    /* Tim vi tri tra ve thich hop */
+    ret = (void *)(ALIGN(block + sizeof(blk) + sizeof(blk *), align));
+    /* Luu con tro den vi tri giu thong tin cua block */
+    *(blk **)((size_t)ret - sizeof(blk *)) = blk_head;
+    return ret;
+}
+
+/* Ham nay khong nhat thiet phai tra ve con tro (void *), tuy nhien em lam theo prototype de bai yeu cau */
+void *aligned_free(void *ptr)
+{
+    if (ptr == NULL)
+        return NULL;
+    /* Tro den vi tri luu thong tin cua block */
+    blk *blk_head = *((blk **)((size_t)ptr - sizeof(blk *)));
+    void *prg_brk = sbrk(0);
+    /* Neu block nam o sat diem break, (neu co thi block nay phai o tail) */
+    if ((size_t)blk_head + blk_head->size == (size_t)prg_brk)
+    {
+        if (head == tail)
+        {
+            head = NULL;
+            tail = NULL;
+        }
+        else
+        {
+            blk *tmp = head;
+            while (tmp != NULL)
+            {
+                if (tmp->next == tail)
+                {
+                    tmp->next = NULL;
+                    tail = tmp;
+                }
+                tmp = tmp->next;
+            }
+        }
+        sbrk(0 - (unsigned int)blk_head->size);
+        return NULL;
+    }
+    /* Neu khong giai phong duoc vung nho, danh dau block la "trong" */
+    blk_head->is_free = 1;
+    /* Tra ve con tro toi vi tri luu thong tin cua block (co the dung de debug) */
+    return (void *)blk_head;
+}

Lab4/ex1.c~

@@ -0,0 +1,71 @@
+#include "ex1.h"
+
+memNode *findFree(size_t size)
+{
+    memNode *cur = head;
+    while (cur != NULL) {
+        if (cur->isFree == 1 && cur->size >= size)
+            return cur;
+        cur = cur->next;
+    }
+    return NULL;
+}
+
+void *aligned_malloc(unsigned int size, unsigned int align)
+{
+    if (size == 0)
+        return NULL;
+    if (ceil(log2((long)align)) != floor(log2((long)align)))
+        return NULL;
+    unsigned int total_size = size + align - 1 + sizeof(memNode);
+    memNode *header = findFree(total_size);
+    void *ret = NULL;
+    if (header != NULL) {
+        header->isFree = 0;
+        ret = (void *) (((size_t)header + sizeof(memNode) + align - 1) & ~((size_t) align - 1));
+        *((void **)((size_t)ret - sizeof(memNode))) = header;
+        return ret;
+    }
+    void *block = sbrk(total_size);
+    if (block == (void *) -1)
+        return NULL;
+    header = block;
+    header->size = total_size;
+    header->block = (size_t)block;
+    header->isFree = 0;
+    header->next = NULL;
+    if (head == NULL)
+        head = header;
+    if (tail != NULL)
+        tail->next = header;
+    tail = header;
+    ret = (void *) (((size_t)header + sizeof(memNode) + align - 1) & ~((size_t) align - 1));
+    *((void **)((size_t)ret - sizeof(memNode))) = header;
+    return ret;
+}
+
+void aligned_free(void *ptr)
+{
+    if (ptr == NULL)
+        return;
+    memNode *header = (memNode *)((size_t)ptr - sizeof(memNode));
+    void *prgBrk = sbrk(0);
+    if (header->block + header->size == (size_t)prgBrk) {
+        if (head == tail) {
+            head = NULL;
+            tail = NULL;
+        } else {
+            memNode *tmp = head;
+            while (tmp != NULL) {
+                if (tmp->next == tail) {
+                    tmp->next = NULL;
+                    tail = tmp;
+                }
+                tmp = tmp->next;
+            }
+        }
+        sbrk(0 - (unsigned int)header->size - sizeof(memNode));
+        return;
+    }
+    header->isFree = 1;
+}

Lab4/ex1.h

@@ -0,0 +1,26 @@
+#ifndef EX1_H
+#define EX1_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define ALIGN(size, align) ((((size_t)size) + (align - 1)) & ~((size_t)align - 1))
+#define IS_POWER_OF_2(num) ((num != 0) && ((num & (num - 1)) == 0))
+
+struct newStruct
+{
+    unsigned int size;
+    unsigned int is_free;
+    struct newStruct *next;
+};
+
+typedef struct newStruct blk;
+
+static blk *head = NULL, *tail = NULL;
+
+blk *find_fit(unsigned int size);
+void *aligned_malloc(unsigned int size, unsigned int align);
+void *aligned_free(void *ptr);
+
+#endif // EX1_H

Lab4/ex1_bak.c

@@ -0,0 +1,86 @@
+#include "ex1.h"
+
+/* Tim block trong */
+memNode *findFree(size_t size)
+{
+    memNode *cur = head;
+    while (cur != NULL)
+    {
+        if (cur->isFree == 1 && cur->size >= size)
+            return cur;
+        cur = cur->next;
+    }
+    return NULL;
+}
+
+void *aligned_malloc(unsigned int size, unsigned int align)
+{
+    if (size == 0)
+        return NULL;
+    /* Kiem tra so mu cua 2 */
+    if (ceil(log2((float)align)) != floor(log2((float)align)))
+        return NULL;
+    /* Tong gia tri do lon cua block can xin */
+    unsigned int total_size = size + align - 1 + sizeof(memNode);
+    memNode *header = findFree(total_size);
+    void *ret = NULL;
+    if (header != NULL)
+    {
+        header->isFree = 0;
+        ret = (void *)(((size_t)header + sizeof(memNode) + align - 1) & ~((size_t)align - 1));
+        *((void **)((size_t)ret - sizeof(memNode))) = header;
+        return ret;
+    }
+    void *block = sbrk(total_size);
+    if (block == (void *)-1)
+        return NULL;
+    header = block;
+    header->size = total_size;
+    header->block = (size_t)block;
+    header->isFree = 0;
+    header->next = NULL;
+    if (head == NULL)
+        head = header;
+    if (tail != NULL)
+        tail->next = header;
+    tail = header;
+    /* Tim vi tri tra ve thoa man */
+    ret = (void *)(((size_t)header + sizeof(memNode) + align - 1) & ~((size_t)align - 1));
+    /* Luu tru thong tin block tai khong gian truoc gia tri tra ve */
+    *((void **)((size_t)ret - sizeof(memNode))) = header;
+    return ret;
+}
+
+void aligned_free(void *ptr)
+{
+    if (ptr == NULL)
+        return;
+    /* Lay lai thong tin cua block */
+    memNode *header = (memNode *)((size_t)ptr - sizeof(memNode));
+    void *prgBrk = sbrk(0);
+    /* Neu block nam o sat diem break */
+    if (header->block + header->size == (size_t)prgBrk)
+    {
+        if (head == tail)
+        {
+            head = NULL;
+            tail = NULL;
+        }
+        else
+        {
+            memNode *tmp = head;
+            while (tmp != NULL)
+            {
+                if (tmp->next == tail)
+                {
+                    tmp->next = NULL;
+                    tail = tmp;
+                }
+                tmp = tmp->next;
+            }
+        }
+        sbrk(0 - (unsigned int)header->size - sizeof(memNode));
+        return;
+    }
+    header->isFree = 1;
+}

Lab4/main.c

@@ -0,0 +1,15 @@
+#include "ex1.h"
+#include <math.h>
+
+int main(int argc, char *argv[])
+{
+    printf("PID: %d\n", getpid());
+    for (unsigned int align = 2; align <= pow(2, 22); align *= 2)
+    {
+        void *p = aligned_malloc(1024, align);
+        printf("%10d %p %15ld %ld \n", align, p,
+               (unsigned long)p, ((unsigned long)p) % align);
+        aligned_free(p);
+    }
+    return 0;
+}