#include<dirent.h>#include<limits.h>#include<sys/stat.h>#include<stdio.h>#include<unistd.h>#include<stdlib.h>#include<string.h>#define FTW_F 1 //标记非目录文件#define FTW_D 2 //标记目录文件#define FTW_DNR 3 //标记不可读目录#define FTW_NS 4 //标记不可获得stat的文件static char *fullpath; //保存文件的全路径static size_t pathlen; //保存文件的路径长度//定义处理文件的函数typedef int Myfunc(const char *,const struct stat*,int);static Myfunc myfunc;static int myftw(char *,Myfunc *);static int dopath(Myfunc *);char *path_alloc(size_t *size_t);/*nreg：普通文件的个数； ndir： 目录文件的数量； nblk：块特殊文件的数量nchr：字符特殊文件的数量 nfifo：管道特殊文件的数量nslink：符号连接特殊文件的数量； nsock：套接字文件数量； ntot：总文件数量*/static long nreg,ndir,nblk,nchr,nfifo,nslink,nsock,ntot;int main( int argc, char *argv[]){int ret;if(argc != 2){printf("falut command input !\n");exit(1);}//计算各类文件的个数ret = myftw(argv[1],myfunc);ntot = nreg + ndir + nblk + nchr + nfifo + nslink + nsock;//避免除以0if(ntot == 0){ntot = 1;}printf("regular files = %7ld,%5.2f %%\n",nreg,nreg*100.0 / ntot);printf("direciotn files = %7ld,%5.2f %%\n",ndir,ndir*100.0 / ntot);printf("block special = %7ld,%5.2f %%\n",nblk,nblk*100.0 / ntot);printf("char special = %7ld,%5.2f %%\n",nchr,nchr*100.0 / ntot);printf("FIFOS = %7ld,%5.2f %%\n",nfifo,nfifo*100.0 / ntot);printf("symbolic links = %7ld,%5.2f %%\n",nslink,nslink*100.0 / ntot);printf("sockers = %7ld,%5.2f %%\n",nsock,nsock*100.0 / ntot);}//处理pathname并保存在一个全局的字符数组中，调用dopathstatic int myftw(char *pathname,Myfunc *func){//为保存路径的字符串数组分配空间fullpath = path_alloc(&pathlen);//如果分配内存空间不够就重新分配if(pathlen <= strlen(pathname)){pathlen = strlen(pathname) * 2;if((fullpath = realloc(fullpath,pathlen )) == NULL);printf("realloc failed\n");}//将路径名参数保存到全路径中，fullpath是全局变量，dopath函数可以调用 strcpy(fullpath,pathname);return (dopath(func));}//路径数组分配char *path_alloc(size_t *size){char *p = NULL;if(!size)return NULL;p = malloc(256);if(p)*size = 256;else*size = 0;return p;}//dopath用于判断是否是目录，然后根据选择情况是直接进入myfun函数取技术//还是递归调用dopath函数static int dopath(Myfunc *func){struct stat statbuf;struct dirent *dirp;DIR *dp;int ret,n;//调用lstat获取路径名的stat信息，如果不成功，调用func函数，并传递给FTW_NSif(lstat(fullpath,&statbuf) < 0)return (func(fullpath, &statbuf, FTW_NS));//查看文件stat结构的st_mode，如果不是目录，调用func函数 //并传递给FTW_F，交由myfun进一步判断文件类型 if(S_ISDIR(statbuf.st_mode) == 0)return(func(fullpath,&statbuf,FTW_F));//最后一种情况就是该路径名代表的是一个目录，此次的fun的正常情况返回0//所以执行完func后还不会返回，会继续执行funcif((ret = func(fullpath,&statbuf,FTW_D)) != 0)return(ret);//路径处理，扩充路径空间长度n = strlen(fullpath);if(n + NAME_MAX + 2 > pathlen){pathlen *= 2;if((fullpath = realloc(fullpath,pathlen)) == NULL){printf("realoc failed\n");}}fullpath[n++] = '/';fullpath[n] = 0;//处理每个目录项if((dp = opendir(fullpath)) == NULL)return (func(fullpath,&statbuf,FTW_DNR));while((dirp = readdir(dp)) != NULL){//忽略当前目录(.)和上一级目录(..)以避免进入死循环if(strcmp(dirp->d_name,".") == 0 ||strcmp(dirp->d_name,"..") == 0 )continue;strcpy(&fullpath[n],dirp->d_name); //在“/”之后加上当前目录项的命中if((ret = dopath(func)) != 0) //然后采用新的路径名递递归的调用dopathbreak;}fullpath[n-1] = 0;//关闭目录if(closedir(dp) < 0 )printf("can't close directory %s",fullpath);return ret;}//通过stat结构的st_mode字段来判断文件的类型，并计数static int myfunc(const char *pathname,const struct stat *statptr,int type){switch(type){//会与非目录情况进行处理case FTW_F:switch (statptr->st_mode & S_IFMT){case S_IFREG: nreg++; break;case S_IFBLK: nblk++; break;case S_IFCHR: nchr++; break;case S_IFIFO: nfifo++; break;case S_IFLNK:nslink++; break;case S_IFSOCK: nsock++;break;case S_IFDIR: printf("for S_IFDIR for %s",pathname);}break;//对于目录文件进行处理case FTW_D:ndir++;break;//对于不可读目录进行处理case FTW_DNR:printf("%s dir isn't read",pathname);break;case FTW_NS:printf("%s stat error",pathname);default:printf("%d type aren't identified, path is %s",type,pathname);}return 0;}
