重载malloc

#include <stdio.h>#include <malloc.h>/* Prototypes for our hooks.  */static void my_init_hook(void);static void *my_malloc_hook(size_t, const void *);/* Variables to save original hooks. */static void *(*old_malloc_hook)(size_t, const void *);/* Override initializing hook from the C library. */void (*__malloc_initialize_hook) (void) = my_init_hook;static voidmy_init_hook(void){    old_malloc_hook = __malloc_hook;    __malloc_hook = my_malloc_hook;}static void *my_malloc_hook(size_t size, const void *caller){    void *result;    /* Restore all old hooks */    __malloc_hook = old_malloc_hook;    /* Call recursively */    result = malloc(size);    /* Save underlying hooks */    old_malloc_hook = __malloc_hook;    /* printf() might call malloc(), so protect it too. */    printf("malloc(%u) called from %p returns %p\n",            (unsigned int) size, caller, result);    /* Restore our own hooks */    __malloc_hook = my_malloc_hook;    return result;}