root/user/ls.c

DEFINITIONS

1. fmtname
2. ls
3. main

   1 #include "kernel/types.h"
   2 #include "kernel/stat.h"
   3 #include "user/user.h"
   4 #include "kernel/fs.h"
   5 #include "kernel/fcntl.h"
   6 
   7 char*
   8 fmtname(char *path)
   9 {
  10   static char buf[DIRSIZ+1];
  11   char *p;
  12 
  13   // Find first character after last slash.
  14   for(p=path+strlen(path); p >= path && *p != '/'; p--)
  15     ;
  16   p++;
  17 
  18   // Return blank-padded name.
  19   if(strlen(p) >= DIRSIZ)
  20     return p;
  21   memmove(buf, p, strlen(p));
  22   memset(buf+strlen(p), ' ', DIRSIZ-strlen(p));
  23   return buf;
  24 }
  25 
  26 void
  27 ls(char *path)
  28 {
  29   char buf[512], *p;
  30   int fd;
  31   struct dirent de;
  32   struct stat st;
  33 
  34   if((fd = open(path, O_RDONLY)) < 0){
  35     fprintf(2, "ls: cannot open %s\n", path);
  36     return;
  37   }
  38 
  39   if(fstat(fd, &st) < 0){
  40     fprintf(2, "ls: cannot stat %s\n", path);
  41     close(fd);
  42     return;
  43   }
  44 
  45   switch(st.type){
  46   case T_DEVICE:
  47   case T_FILE:
  48     printf("%s %d %d %d\n", fmtname(path), st.type, st.ino, (int) st.size);
  49     break;
  50 
  51   case T_DIR:
  52     if(strlen(path) + 1 + DIRSIZ + 1 > sizeof buf){
  53       printf("ls: path too long\n");
  54       break;
  55     }
  56     strcpy(buf, path);
  57     p = buf+strlen(buf);
  58     *p++ = '/';
  59     while(read(fd, &de, sizeof(de)) == sizeof(de)){
  60       if(de.inum == 0)
  61         continue;
  62       memmove(p, de.name, DIRSIZ);
  63       p[DIRSIZ] = 0;
  64       if(stat(buf, &st) < 0){
  65         printf("ls: cannot stat %s\n", buf);
  66         continue;
  67       }
  68       printf("%s %d %d %d\n", fmtname(buf), st.type, st.ino, (int) st.size);
  69     }
  70     break;
  71   }
  72   close(fd);
  73 }
  74 
  75 int
  76 main(int argc, char *argv[])
  77 {
  78   int i;
  79 
  80   if(argc < 2){
  81     ls(".");
  82     exit(0);
  83   }
  84   for(i=1; i<argc; i++)
  85     ls(argv[i]);
  86   exit(0);
  87 }