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 #ifdef MODULE
  10 #include <linux/module.h>
  11 #endif
  12 
  13 #include <asm/segment.h>
  14 
  15 #include <linux/errno.h>
  16 #include <linux/sched.h>
  17 #include <linux/fs.h>
  18 #include <linux/minix_fs.h>
  19 #include <linux/stat.h>
  20 
  21 static int minix_readlink(struct inode *, char *, int);
  22 static int minix_follow_link(struct inode *, struct inode *, int, int, struct inode **);
  23 
  24 /*
  25  * symlinks can't do much...
  26  */
  27 struct inode_operations minix_symlink_inode_operations = {
  28         NULL,                   /* no file-operations */
  29         NULL,                   /* create */
  30         NULL,                   /* lookup */
  31         NULL,                   /* link */
  32         NULL,                   /* unlink */
  33         NULL,                   /* symlink */
  34         NULL,                   /* mkdir */
  35         NULL,                   /* rmdir */
  36         NULL,                   /* mknod */
  37         NULL,                   /* rename */
  38         minix_readlink,         /* readlink */
  39         minix_follow_link,      /* follow_link */
  40         NULL,                   /* bmap */
  41         NULL,                   /* truncate */
  42         NULL                    /* permission */
  43 };
  44 
  45 static int minix_follow_link(struct inode * dir, struct inode * inode,
     /*  */
  46         int flag, int mode, struct inode ** res_inode)
  47 {
  48         int error;
  49         struct buffer_head * bh;
  50 
  51         *res_inode = NULL;
  52         if (!dir) {
  53                 dir = current->fs->root;
  54                 dir->i_count++;
  55         }
  56         if (!inode) {
  57                 iput(dir);
  58                 return -ENOENT;
  59         }
  60         if (!S_ISLNK(inode->i_mode)) {
  61                 iput(dir);
  62                 *res_inode = inode;
  63                 return 0;
  64         }
  65         if (current->link_count > 5) {
  66                 iput(inode);
  67                 iput(dir);
  68                 return -ELOOP;
  69         }
  70         if (!(bh = minix_bread(inode, 0, 0))) {
  71                 iput(inode);
  72                 iput(dir);
  73                 return -EIO;
  74         }
  75         iput(inode);
  76         current->link_count++;
  77         error = open_namei(bh->b_data,flag,mode,res_inode,dir);
  78         current->link_count--;
  79         brelse(bh);
  80         return error;
  81 }
  82 
  83 static int minix_readlink(struct inode * inode, char * buffer, int buflen)
     /*  */
  84 {
  85         struct buffer_head * bh;
  86         int i;
  87         char c;
  88 
  89         if (!S_ISLNK(inode->i_mode)) {
  90                 iput(inode);
  91                 return -EINVAL;
  92         }
  93         if (buflen > 1023)
  94                 buflen = 1023;
  95         bh = minix_bread(inode, 0, 0);
  96         iput(inode);
  97         if (!bh)
  98                 return 0;
  99         i = 0;
 100         while (i<buflen && (c = bh->b_data[i])) {
 101                 i++;
 102                 put_fs_byte(c,buffer++);
 103         }
 104         brelse(bh);
 105         return i;
 106 }
/* */
root/fs/minix/symlink.c

DEFINITIONS
