util.c

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.如何读取目录的内容 2.目录排序 3.文件类型以及如何知道文件的类型 4.位操作及掩码的使用 5.用户与组ID数据库 6

#include"globals.h"
int getblocks(long size)
{  
  long blocks;
  blocks=size/4096;
  if(size%4096!=0)
     ++blocks;
  blocks<<=2;
  return blocks;
}
void print_size_kmg(const long size)
{
  if(size<1024)
    printf("%8ld ", size);
  else if(size<1024*1024)
    printf("%8.1lfK ", (size/1024.0));
  else if(size<1024*1024*1024)
    printf("%8.1lfM ", (size/1024.0/1024.0));
  else 
    printf("%8.1lfG ", (size/1024.0/1024.0/1024.0));
}
void print_filename(const char *filename, int mode)
{  
  if(mode&(S_IXUSR||S_IXGRP||S_IXOTH))
    printf(GREEN);                    //green
  switch(mode&(S_IFMT))
  {
    //case S_IFREG: printf(""); break;
    case S_IFDIR: printf(BLUE); break; //blue
    //case S_IFBLK: printf(""); break;
    //case S_IFCHR: printf(""); break;
    case S_IFIFO: printf(YELLOW); break;  //yellow
    case S_IFLNK: printf(CYAN); break;  //cyan
    case S_IFSOCK: printf(PURPLE); break; //purple
  }
  printf("%s", filename);
  printf(NONE);
}