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调用回调函数,数组参数地址偏移出错解决思路

2012-03-15 
调用回调函数,数组参数地址偏移出错在下面程序中(*func)(arrlist)函数无法正常调用而GetMaxBook(arrlist)

调用回调函数,数组参数地址偏移出错
在下面程序中(*func)(arrlist)函数无法正常调用而GetMaxBook(arrlist)函数可以正常调用,经过调试发现func回调函数再获取arrlist数组的地址时出现错误,地址少偏移了4个字节这是为什么?该如何解决?

C代码及相关汇编代码如下:

C/C++ code
typedef void* (*fun)(void *arrlist);struct book{    int id;    char name[10];};void *Max(void * arrlist,fun func);struct book GetMaxBook(BOOK b);54: void *Max(void * arrlist,fun func)                                                                   55:  {    004135E0 55               push        ebp  004135E1 8B EC            mov         ebp,esp 004135E3 81 EC D8 00 00 00 sub         esp,0D8h 004135E9 53               push        ebx  004135EA 56               push        esi  004135EB 57               push        edi  004135EC 8D BD 28 FF FF FF lea         edi,[ebp-0D8h] 004135F2 B9 36 00 00 00   mov         ecx,36h 004135F7 B8 CC CC CC CC   mov         eax,0CCCCCCCCh 004135FC F3 AB            rep stos    dword ptr es:[edi]     56:     (*func)(arrlist);//func为GetMaxBook函数指针004135FE 8B F4            mov         esi,esp 00413600 8B 45 08         mov         eax,dword ptr [arrlist] 00413603 50               push        eax  00413604 FF 55 0C         call        dword ptr [func] 00413607 83 C4 04         add         esp,4 0041360A 3B F4            cmp         esi,esp 0041360C E8 20 DB FF FF   call        @ILT+300(__RTC_CheckEsp) (411131h)     57:     GetMaxBook(arrlist);00413611 8B 45 08         mov         eax,dword ptr [arrlist] 00413614 50               push        eax  00413615 8D 8D 2C FF FF FF lea         ecx,[ebp-0D4h] 0041361B 51               push        ecx  0041361C E8 B5 DB FF FF   call        @ILT+465(_GetMaxBook) (4111D6h) 00413621 83 C4 08         add         esp,8     58:     return NULL;00413624 33 C0            xor         eax,eax }    35: struct book GetMaxBook(BOOK b)    36:  {    38:     struct book maxb;    39:     maxb = *b;00413748 8B 45 0C         mov         eax,dword ptr [ebp+0Ch] ;如GetMaxBook(arrlist)为0x00000001则func为0x000000040041374B 8B 08            mov         ecx,dword ptr [eax] 0041374D 89 4D DC         mov         dword ptr [ebp-24h],ecx 00413750 8B 50 04         mov         edx,dword ptr [eax+4] 00413753 89 55 E0         mov         dword ptr [ebp-20h],edx 00413756 8B 48 08         mov         ecx,dword ptr [eax+8] 00413759 89 4D E4         mov         dword ptr [ebp-1Ch],ecx 0041375C 8B 50 0C         mov         edx,dword ptr [eax+0Ch] 0041375F 89 55 E8         mov         dword ptr [ebp-18h],edx 




[解决办法]
应使GetMaxBook定义与fun的定义一致. 下例没有问题:

C/C++ code
#include <stdio.h>typedef struct book{    int id;    char name[10];} *BOOK;typedef void* (*fun)(BOOK arrlist);void *GetMaxBook(BOOK b){  printf("id=%d name=%s\n", b->id, b->name);  return NULL;}void *Max(void *arrlist,fun func){  (*func)(arrlist);  GetMaxBook(arrlist);  return NULL;}int main(){  struct book list[2] = {    {1, "book1"},    {2, "book2"}  };  BOOK arrlist = list;  Max(arrlist, GetMaxBook);  return 0;} 

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