一本书, 一段源码, 推荐给大家
我要推举的是<C Interfaces and Implementations: Techniques for Creating Reusable Software>, 任何程序都离不开分配内存, 下面一段代码来自随书的负责内存分配的代码:
///////////////mem.h
#ifndef MEM_INCLUDED
#define MEM_INCLUDED
#include "except.h"
extern const Except_T Mem_Failed;
extern void *Mem_alloc (long nbytes,
const char *file, int line);
extern void *Mem_calloc(long count, long nbytes,
const char *file, int line);
extern void Mem_free(void *ptr,
const char *file, int line);
extern void *Mem_resize(void *ptr, long nbytes,
const char *file, int line);
#define ALLOC(nbytes) Mem_alloc((nbytes), __FILE__, __LINE__)
#define CALLOC(count, nbytes) Mem_calloc((count), (nbytes), __FILE__, __LINE__)
#define NEW(p) ((p) = ALLOC((long)sizeof *(p)))
#define NEW0(p) ((p) = CALLOC(1, (long)sizeof *(p)))
#define FREE(ptr) ((void)(Mem_free((ptr), __FILE__, __LINE__), (ptr) = 0))
#define RESIZE(ptr, nbytes) ((ptr) = Mem_resize((ptr), (nbytes), __FILE__, __LINE__))
#endif
/////////////mem.c
static char rcsid[] = "$Id: H:/drh/idioms/book/RCS/mem.doc,v 1.12 1997/10/27 23:08:05 drh Exp $";
#include <stdlib.h>
#include <stddef.h>
#include "assert.h"
#include "except.h"
#include "mem.h"
const Except_T Mem_Failed = { "Allocation Failed" };
void *Mem_alloc(long nbytes, const char *file, int line){
void *ptr;
assert(nbytes > 0);
ptr = malloc(nbytes);
if (ptr == NULL)
{
if (file == NULL)
RAISE(Mem_Failed);
else
Except_raise(&Mem_Failed, file, line);
}
return ptr;
}
void *Mem_calloc(long count, long nbytes,
const char *file, int line) {
void *ptr;
assert(count > 0);
assert(nbytes > 0);
ptr = calloc(count, nbytes);
if (ptr == NULL)
{
if (file == NULL)
RAISE(Mem_Failed);
else
Except_raise(&Mem_Failed, file, line);
}
return ptr;
}
void Mem_free(void *ptr, const char *file, int line) {
if (ptr)
free(ptr);
}
void *Mem_resize(void *ptr, long nbytes,
const char *file, int line) {
assert(ptr);
assert(nbytes > 0);
ptr = realloc(ptr, nbytes);
if (ptr == NULL)
{
if (file == NULL)
RAISE(Mem_Failed);
else
Except_raise(&Mem_Failed, file, line);
}
return ptr;
}