diff --git a/src/fifo.c b/src/fifo.c
index f59ef94..f9f82b7 100644
--- a/src/fifo.c
+++ b/src/fifo.c
@@ -1,10 +1,9 @@
-#include <pthread.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdint.h>
-#include "utils.h"
+#include <pthread.h>
 #include "fifo.h"
-#include "spinlock.h"
 
 #define is_power_of_2(x) (((x) != 0) && (((x) & (x - 1)) == 0))
 #define min(a, b) (((a) < (b)) ? (a) : (b))
@@ -14,10 +13,15 @@ struct fifo {
 	int size;
 	int in;
 	int out;
-	struct spinlock lock;
+	pthread_spinlock_t lock;
 };
 
-unsigned int roundup_pow_of_two(unsigned int x)
+#define SPIN_INIT(fxo)    pthread_spin_init(&fxo->lock, PTHREAD_PROCESS_PRIVATE)
+#define SPIN_RELEASE(fxo) pthread_spin_destroy(&fxo->lock)
+#define SPIN_LOCK(fxo)    pthread_spin_lock(&fxo->lock)
+#define SPIN_UNLOCK(fxo)  pthread_spin_unlock(&fxo->lock)
+
+static unsigned int roundup_pow_of_two(unsigned int x)
 {
 	int i = 0;
 	
@@ -40,17 +44,13 @@ fifo_t fifo_new_with_ext_buffer(unsigned char *buffer, unsigned int size)
 	fifo_t fifo;
 	
 	if (!is_power_of_2(size)){
-#ifndef __mingw__
-		log_info("size must be power of 2.");		
-#endif
+		fprintf(stderr, "size must be power of 2.");		
 		return NULL;	
 	}
 	
 	fifo = calloc(1, sizeof *fifo);
 	if (!fifo) {
-#ifndef __mingw__
-		log_info("fifo_init; out of memory.");		
-#endif
+		fprintf(stderr, "kfifo_init; out of memory.");		
 		return NULL;	
 	}	
 	
@@ -61,23 +61,49 @@ fifo_t fifo_new_with_ext_buffer(unsigned char *buffer, unsigned int size)
 	return fifo;
 }
 
+unsigned int fifo_cap(fifo_t fifo)
+{
+	return fifo->size;
+}
+
+int  fifo_resize(fifo_t fifo, unsigned int size)
+{
+	unsigned char *buffer, *op;
+	unsigned int xlen;
+
+	if (!is_power_of_2(size)) {
+		fprintf(stderr, "size is not of power2 %d.\n", size);			
+		size = roundup_pow_of_two(size);
+	}
+	buffer = malloc(size);
+	if (!buffer) {
+		return -1;
+	}
+	xlen = fifo_get(fifo, buffer, size);
+	SPIN_LOCK(fifo);
+	op = fifo->buffer;
+	fifo->buffer = buffer;
+	fifo->size = size;
+	fifo->in = xlen;
+	fifo->out = 0;
+	SPIN_UNLOCK(fifo);
+	free(op);
+	return 0;
+}
+
 fifo_t fifo_new(unsigned int size)
 {
 	unsigned char *buffer;
 	fifo_t fifo;
 
 	if (!is_power_of_2(size)) {
-#ifndef __mingw__
-		log_info("size is not of power2.");			
-#endif
+		fprintf(stderr, "size is not of power2 %d.\n", size);			
 		size = roundup_pow_of_two(size);
 	}
 
 	buffer = calloc(1, size);
 	if (!buffer) {
-#ifndef __mingw__
-		log_info("fifo_alloc: out of memory.");	
-#endif
+		fprintf(stderr, "kfifo_alloc: out of memory.");	
 		return NULL;	
 	}
 
diff --git a/src/spinlock.h b/src/spinlock.h
deleted file mode 100644
index 9460f0d..0000000
--- a/src/spinlock.h
+++ /dev/null
@@ -1,72 +0,0 @@
-#ifndef __XA_SPINLOCK_H__
-#define __XA_SPINLOCK_H__
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#define SPIN_INIT(x)    spinlock_init(&(x)->lock)
-#define SPIN_LOCK(x)    spinlock_lock(&(x)->lock)
-#define SPIN_UNLOCK(x)  spinlock_unlock(&(x)->lock)
-#define SPIN_RELEASE(x) spinlock_destroy(&(x)->lock)
-
-/*
- * Use gcc's instric instructions implentate 
- * spinlock.
- */
-#ifndef __UNUSED__
-#define __UNUSED__ __attribute__((unused))
-#endif
-
-struct spinlock {
-	int lock;
-};
-
-/*
- * Initialize spinlock.
- */
-static inline void __UNUSED__ spinlock_init(struct spinlock *lock)
-{
-	lock->lock = 0;
-}
-
-/*
- * Lock
- */
-static inline void __UNUSED__ spinlock_lock(struct spinlock *lock)
-{
-	while (__sync_lock_test_and_set(&lock->lock, 1))
-		;
-}
-
-/*
- * Trylock.
- *
- * return 1 on locked, 0 on faile.
- */
-static inline int __UNUSED__ spinlock_trylock(struct spinlock *lock)
-{
-	return __sync_lock_test_and_set(&lock->lock, 1) == 0;
-}
-
-/*
- * Unlock.
- */
-static inline void __UNUSED__ spinlock_unlock(struct spinlock *lock)
-{
-	__sync_lock_release(&lock->lock);
-}
-
-/*
- * Deinitialize.
- */
-static inline void __UNUSED__ spinlock_destroy(struct spinlock *lock)
-{
-	(void)lock;
-}
-
-#ifdef __cplusplus
-}
-#endif
-#endif
-