/*Ubuntu 14.04平台下
* 利用多线程 mmap文件内存共享
* 实现文件拷贝
*/
/*more thread copy files
* 默认情况下开启5个线程
*/
#include <stdio.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#include <errno.h>
#include <sys/types.h>
/*thread number*/
#define T_NUM 5
#define ITEMS 50
typedef struct{
/*off size,file size,thread identifier */
int off,size,t_no;
}arg_t;
void err_sys(void *str)
{
perror(str);
exit(1);
}
void err_usr(char *str)
{
fputs(str,stderr);
exit(1);
}
char *pch_sour_file,*pch_des_file;
int *pi_has_done;
int pnum=T_NUM;
/*arg {off,size,t_no}*/
void *pt_cp(void *arg)
{
if(NULL==arg)
return NULL;
arg_t *arg_p;int i;
char *pch,*qch;
arg_p=(arg_t *)arg;
pch=pch_sour_file+arg_p->off,qch=pch_des_file+arg_p->off;
for(i=0;i<arg_p->size;i++)
{
*qch++=*pch++;
pi_has_done[arg_p->t_no]++;
/*usleep function is like to sleep*/
usleep(5000);
}
return NULL;
}
void *display_pro(void * arg)
{
int size,draw=0,sum,i,j,interval;
size=(int)arg;
interval=size/ITEMS;
while(draw<ITEMS)
{
for(i=0,sum=0;i<pnum;i++)
sum+=pi_has_done[i];
j=sum/interval+1;
for(;j>draw;draw++)
putchar('=');fflush(stdout);
}
printf("
");
return NULL;
}
int main(int argc,char *argv[])
{
int src,dst,i,len,off;
struct stat statbuff;
pthread_t *tid;
arg_t *arg_arr;
if(argc!=3 && argc!=4)
err_usr("usage：cp src dst [pthread_no]
");
/*修改线程数*/
if(argc==4)
pnum=atoi(argv[3]);
src=open(argv[1],O_RDONLY);
if(src<0)
{printf("fail to open %s
",argv[1]);return -1;}
dst=open(argv[2],O_RDWR | O_CREAT | O_TRUNC,0644);
if(dst<-1)
{printf("fail to open %s
",argv[2]);return -1;}
if(fstat(src,&statbuff)==-1)
{
err_sys("fail to stat");
return -1;
}
/*创建同样的大小文件*/
lseek(dst,statbuff.st_size-1,SEEK_SET);
write(dst,"a",1);
pch_sour_file=(char *)mmap(NULL,statbuff.st_size,PROT_READ,MAP_SHARED,src,0);
if(pch_sour_file==MAP_FAILED)
{
err_sys("fail to mmap");
return -1;
}
pch_des_file=(char *)mmap(NULL,statbuff.st_size,PROT_WRITE,MAP_SHARED,dst,0);
if(pch_des_file==MAP_FAILED)
{
err_sys("fail to mmap");
return -1;
}
/*close file discription*/
close(src);close(dst);
/*crate pthread tid[n+1]*/
tid=(pthread_t *)malloc(sizeof(pthread_t)*(pnum+1));
if(NULL==tid)
{
err_sys("fail to malloc");
return -1;
}
/*per thread copy bite*/
/*每个线程需要的拷贝的字节数*/
pi_has_done=(int *)calloc(sizeof(int),pnum);
if(NULL==pi_has_done)
{
err_sys("fail to calloc");
return -1;
}
/*arg_arr[n] per thread task*/
arg_arr=(arg_t *)malloc(sizeof(arg_t)*pnum);
if(NULL==arg_arr)
{
err_sys("fail to malloc");
return -1;
}
/*allocating task*/
len=statbuff.st_size/pnum,off=0;
for(i=0;i<pnum;i++,off+=len)
arg_arr[i].off=off,arg_arr[i].size=len,arg_arr[i].t_no=i;
/*reminder byte add last struct arg_t*/
arg_arr[pnum-1].size+=statbuff.st_size%pnum;
/*create pthread to do*/
for(i=0;i<pnum;i++)
pthread_create((tid+i),NULL,pt_cp,(void *)(arg_arr+i));
/*专门显示进度的线程*/
pthread_create((tid+pnum),NULL,display_pro,(void *)statbuff.st_size);
for(i=0;i<pnum;i++)
pthread_join(tid[i],NULL);
/*关闭文件共享*/
munmap(pch_sour_file,statbuff.st_size);
munmap(pch_des_file,statbuff.st_size);
/*回收内存*/
free(tid);
free(arg_arr);
free(pi_has_done);
return 0;
}
效果图如下所示：版权声明：本文为博主原创文章，未经博主允许不得转载。