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   buf[sizeof(buf) - 1] = '\0';
  24   return buf;
  25 }
  26 
  27 void
  28 ls(char *path)
  29 {
  30   char buf[512], *p;
  31   int fd;
  32   struct dirent de;
  33   struct stat st;
  34 
  35   if ((fd = open(path, O_RDONLY)) < 0) {
  36     fprintf(2, "ls: cannot open %s\n", path);
  37     return;
  38   }
  39 
  40   if (fstat(fd, &st) < 0) {
  41     fprintf(2, "ls: cannot stat %s\n", path);
  42     close(fd);
  43     return;
  44   }
  45 
  46   switch (st.type) {
  47   case T_DEVICE:
  48   case T_FILE:
  49     printf("%s %d %d %d\n", fmtname(path), st.type, st.ino, (int)st.size);
  50     break;
  51 
  52   case T_DIR:
  53     if (strlen(path) + 1 + DIRSIZ + 1 > sizeof buf) {
  54       printf("ls: path too long\n");
  55       break;
  56     }
  57     strcpy(buf, path);
  58     p = buf + strlen(buf);
  59     *p++ = '/';
  60     while (read(fd, &de, sizeof(de)) == sizeof(de)) {
  61       if (de.inum == 0)
  62         continue;
  63       memmove(p, de.name, DIRSIZ);
  64       p[DIRSIZ] = 0;
  65       if (stat(buf, &st) < 0) {
  66         printf("ls: cannot stat %s\n", buf);
  67         continue;
  68       }
  69       printf("%s %d %d %d\n", fmtname(buf), st.type, st.ino, (int)st.size);
  70     }
  71     break;
  72   }
  73   close(fd);
  74 }
  75 
  76 int
  77 main(int argc, char *argv[])
  78 {
  79   int i;
  80 
  81   if (argc < 2) {
  82     ls(".");
  83     exit(0);
  84   }
  85   for (i = 1; i < argc; i++)
  86     ls(argv[i]);
  87   exit(0);
  88 }