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;
}

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