fs/minix/symlink.c

/* */
This source file includes following definitions.
minix_follow_link
minix_readlink
   1 /*
   2  *  linux/fs/minix/symlink.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *
   6  *  minix symlink handling code
   7  */
   8 
   9 #include <asm/segment.h>
  10 
  11 #include <linux/errno.h>
  12 #include <linux/sched.h>
  13 #include <linux/fs.h>
  14 #include <linux/minix_fs.h>
  15 #include <linux/stat.h>
  16 
  17 static int minix_readlink(struct inode *, char *, int);
  18 static int minix_follow_link(struct inode *, struct inode *, int, int, struct inode **);
  19 
  20 /*
  21  * symlinks can't do much...
  22  */
  23 struct inode_operations minix_symlink_inode_operations = {
  24         NULL,                   /* no file-operations */
  25         NULL,                   /* create */
  26         NULL,                   /* lookup */
  27         NULL,                   /* link */
  28         NULL,                   /* unlink */
  29         NULL,                   /* symlink */
  30         NULL,                   /* mkdir */
  31         NULL,                   /* rmdir */
  32         NULL,                   /* mknod */
  33         NULL,                   /* rename */
  34         minix_readlink,         /* readlink */
  35         minix_follow_link,      /* follow_link */
  36         NULL,                   /* bmap */
  37         NULL,                   /* truncate */
  38         NULL                    /* permission */
  39 };
  40 
  41 static int minix_follow_link(struct inode * dir, struct inode * inode,
     /*  */
  42         int flag, int mode, struct inode ** res_inode)
  43 {
  44         int error;
  45         struct buffer_head * bh;
  46 
  47         *res_inode = NULL;
  48         if (!dir) {
  49                 dir = current->root;
  50                 dir->i_count++;
  51         }
  52         if (!inode) {
  53                 iput(dir);
  54                 return -ENOENT;
  55         }
  56         if (!S_ISLNK(inode->i_mode)) {
  57                 iput(dir);
  58                 *res_inode = inode;
  59                 return 0;
  60         }
  61         if (current->link_count > 5) {
  62                 iput(inode);
  63                 iput(dir);
  64                 return -ELOOP;
  65         }
  66         if (!(bh = minix_bread(inode, 0, 0))) {
  67                 iput(inode);
  68                 iput(dir);
  69                 return -EIO;
  70         }
  71         iput(inode);
  72         current->link_count++;
  73         error = open_namei(bh->b_data,flag,mode,res_inode,dir);
  74         current->link_count--;
  75         brelse(bh);
  76         return error;
  77 }
  78 
  79 static int minix_readlink(struct inode * inode, char * buffer, int buflen)
     /*  */
  80 {
  81         struct buffer_head * bh;
  82         int i;
  83         char c;
  84 
  85         if (!S_ISLNK(inode->i_mode)) {
  86                 iput(inode);
  87                 return -EINVAL;
  88         }
  89         if (buflen > 1023)
  90                 buflen = 1023;
  91         bh = minix_bread(inode, 0, 0);
  92         iput(inode);
  93         if (!bh)
  94                 return 0;
  95         i = 0;
  96         while (i<buflen && (c = bh->b_data[i])) {
  97                 i++;
  98                 put_fs_byte(c,buffer++);
  99         }
 100         brelse(bh);
 101         return i;
 102 }
/* */
root/fs/minix/symlink.c

DEFINITIONS
