do_ls2.c

来自「实现UNIX下的ls全部功能,同时添加了可以生成目录树.实现内容:1.如何读取目」· C语言 代码 · 共 141 行

#include"globals.h"
void do_ls2(const char *dir, const struct flg opt_flg)
{
  int n,i,total;
  total=0;
  struct dirent **namelist;
  if(opt_flg.aflg==3)
     dostat(dir,opt_flg);
  else 
  {  
    switch(opt_flg.oflg)
    {
      case 0: n=scandir(dir, &namelist, 0, alphasort);break;
      case 1: n=scandir(dir, &namelist, 0, ctimesort);break;
      case 2: n=scandir(dir, &namelist, 0, blocksort);break;
      case 3: n=scandir(dir, &namelist, 0, mtimesort);break;
      case 4: n=scandir(dir, &namelist, 0, atimesort);break;
      case 5: n=scandir(dir, &namelist, 0, revalpsort);break;
    }
    if(n<0)
      perror(dir);
    else
    {  
      if(opt_flg.aflg==0){
        for(i=0; i<n; i++){ 
          if(namelist[i]->d_name[0]!='.')  //不显示'.', '..'和以'.'开头的文件
            total+=dostat(namelist[i]->d_name,opt_flg);
          free(namelist[i]);
        }
      }
      else if(opt_flg.aflg==1)
      {
        for(i=0;i<n;i++){
          total+=dostat(namelist[i]->d_name, opt_flg);
          free(namelist[i]);
        }
      }
      else if(opt_flg.aflg==2) 
      {
        for(i=0;i<n;i++){
          if(strcmp(namelist[i]->d_name, ".")!=0&&strcmp(namelist[i]->d_name, "..")!=0)
             total+=dostat(namelist[i]->d_name, opt_flg);
          free(namelist[i]);
        }
      }
      free(namelist);
      printf("total %d\n",total);
    }
  }
}

int dostat(const char *filename, const struct flg opt_flg)
{
  struct stat info;
  int blocks;
  if(stat(filename, &info)==-1)
    perror(filename);
  else {
    if(S_ISDIR(info.st_mode))
      blocks=4;
    else 
      blocks=getblocks((long)info.st_size);
    if(opt_flg.sflg==1)
      printf("%4d ",blocks);
    show_file_info(filename, &info, opt_flg);
    return blocks;
  }
}

void show_file_info(const char *filename, const struct stat *info, const struct flg opt_flg)
{
  char *uid_to_name(), *ctime(),*gid_to_name(),*filemode();
  void mode_to_letters(const int mode, char str[]);
  char modestr[11];
  mode_to_letters(info->st_mode, modestr);
  if(opt_flg.iflg==1)
    printf("%8d ",info->st_ino);
  printf("%s ", modestr);
  printf("%4d ", (int)info->st_nlink);
  if(opt_flg.nflg==0)
     printf("%-8s ", uid_to_name(info->st_uid));
  else 
     printf("%-8d ",info->st_uid);
  if(opt_flg.gflg==0){
     if(opt_flg.nflg==0)
        printf("%-8s ", gid_to_name(info->st_gid));
     else 
        printf("%-8d ", info->st_gid);
  }
  if(opt_flg.hflg==0)
    printf("%8ld ", (long)info->st_size);
  else 
    print_size_kmg((long)info->st_size);
  if(opt_flg.oflg==1)
    printf("%.12s ", 4+ctime(&info->st_ctime));
  else if(opt_flg.oflg==4)
    printf("%.12s ", 4+ctime(&info->st_atime));
  else printf("%.12s ", 4+ctime(&info->st_mtime));
  print_filename(filename, info->st_mode);
  printf("\n");
}

static char perms[11]="_rwxrwxrwx";
void mode_to_letters(const int mode, char str[])
{
  int i, flg;
  flg=0400;
  strcpy(str,"----------");
  if(S_ISDIR(mode))str[0]='d';
  if(S_ISCHR(mode))str[0]='c';
  if(S_ISBLK(mode))str[0]='b';
  for(i=1; i<10; i++ ){
    if(mode&flg)
      str[i]=perms[i];
    flg>>=1;
    }
}
char *uid_to_name(uid_t uid)
{
  struct passwd *getpwuid(), *pw_ptr;
  static char numstr[10];
  if((pw_ptr=getpwuid(uid))==NULL){
    sprintf(numstr, "%d", uid);
    return numstr;
  }
  else
    return pw_ptr->pw_name;
}

char *gid_to_name(gid_t gid)
{
  struct group *getgrgid(), *grp_ptr;
  static char numstr[10];
  if((grp_ptr=getgrgid(gid))==NULL){
    sprintf(numstr, "%d",gid);
    return numstr;
  }
  else
    return grp_ptr->gr_name;
}