我有2个程序,一个使用Windows API获取所有进程信息,并将它们存储在这样的结构 vector 中:
struct Info{
int pid,ppid;
char exeName[256];
}
当我用数据填充结构时,我将back_pushing结构保留在 vector 中。现在,我尝试使用
memcpy()
来存储映射文件中的数据,但是在第二个程序中无法正确读取它。您能帮我弄清楚如何正确读取数据吗?代码程序1:
#define _CRT_SECURE_NO_WARNINGS
#include <Windows.h>
#include <stdio.h>
#include <Tlhelp32.h>
#include <vector>
struct InfoProces {
DWORD pid;
DWORD ppid;
char exeName[256];
};
int main(){
HANDLE hProcesses;
PROCESSENTRY32 pe32;
hProcesses = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS,0);
if (hProcesses == INVALID_HANDLE_VALUE)
{
printf("CreateToolhelp32Snapshot failed. err = %d", GetLastError());
return -1;
}
pe32.dwSize = sizeof(PROCESSENTRY32);
if (!Process32First(hProcesses, &pe32)) {
printf("Process32First failed. err = %d", GetLastError());
CloseHandle(hProcesses);
return -1;
}
HANDLE hdata = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, 1024 * 1024, "data");
if (hdata == NULL) {
printf("Can't create a file mapping. err = %d", GetLastError());
return -1;
}
unsigned char* pdata = (unsigned char*)MapViewOfFile(hdata, FILE_MAP_WRITE, 0, 0, 0);
if (pdata == NULL) {
printf("cant get pointer to mapping file. err = %d", GetLastError());
return -1;
}
do {
InfoProces pi;
pi.pid = pe32.th32ProcessID;
pi.ppid = pe32.th32ParentProcessID;
strcpy(pi.exeName, pe32.szExeFile);
} while (Process32Next(hProcesses, &pe32));
getchar();
CloseHandle(hProcesses);
return 0;
代码程序2:#define _CRT_SECURE_NO_WARNINGS
#include <Windows.h>
#include <vector>
#include <stdio.h>
struct InfoProces {
DWORD pid;
DWORD ppid;
char exeName[256];
};
int main()
{
HANDLE hdata = OpenFileMapping(FILE_MAP_ALL_ACCESS, false, "data");
unsigned char* pdata = (unsigned char*)MapViewOfFile(hdata, FILE_MAP_READ, 0, 0, 0);
if (pdata == NULL) {
printf("cant get pointer to mapped file. err = %d", GetLastError());
return -1;
}
std::vector<InfoProces>processes;
memcpy(&processes,pdata,sizeof(data));
for (std::vector<InfoProces>::iterator i = processes.begin(); i < processes.end(); i++)
printf("Process[%d](parinte[%d]): %s\n", i->pid, i->ppid, i->exeName);
return 0;
}
最佳答案
正如评论所指出的那样,您已经获得了映射 View 的起始地址(pdata
),您只能使用pdata
进行内存共享,而不能使用该进程的任何堆栈地址。
尝试将InfoProces
的内存复制到程序1中的pdata
:
memcpy(pdata, &pi, sizeof(InfoProces));
此外,在程序2中,您没有设置 vector 的大小,应将&processes
替换为processes.data()
。您还需要知道在程序1中添加的数组的大小:std::vector<InfoProces> processes;
processes.resize(count);
memcpy(processes.data(), pdata, sizeof(InfoProces)*count);
以下代码对我有用。程序1 :(记录
InfoProces
的计数并将其保存到pdata
开头的DWORD中)...
unsigned char* pdata = (unsigned char*)MapViewOfFile(hdata, FILE_MAP_WRITE, 0, 0, 0);
if (pdata == NULL) {
printf("cant get pointer to mapping file. err = %d", GetLastError());
return -1;
}
unsigned char* begin = pdata;
//offset a size of DWORD;
DWORD count = 0;
pdata += sizeof(DWORD);
do {
InfoProces pi;
pi.pid = pe32.th32ProcessID;
pi.ppid = pe32.th32ParentProcessID;
strcpy(pi.exeName, pe32.szExeFile);
memcpy(pdata, &pi, sizeof(InfoProces));
pdata += sizeof(InfoProces);
count++;
} while (Process32Next(hProcesses, &pe32));
memcpy(begin, &count, sizeof(DWORD));
getchar();
UnmapViewOfFile(begin);
CloseHandle(hdata);
CloseHandle(hProcesses);
...
程式2:...
unsigned char* pdata = (unsigned char*)MapViewOfFile(hdata, FILE_MAP_READ, 0, 0, 0);
if (pdata == NULL) {
printf("cant get pointer to mapped file. err = %d", GetLastError());
return -1;
}
unsigned char* begin = pdata;
DWORD count = 0;
memcpy(&count, pdata, sizeof(DWORD));
pdata += sizeof(DWORD);
std::vector<InfoProces> processes;
processes.resize(count);
memcpy(processes.data(), pdata, sizeof(InfoProces)*count);
for (std::vector<InfoProces>::iterator i = processes.begin(); i < processes.end(); i++)
printf("Process[%d](parinte[%d]): %s\n", i->pid, i->ppid, i->exeName);
UnmapViewOfFile(begin);
CloseHandle(hdata);
...
最后,不要忘记关闭句柄和取消映射地址。