1 files changed, 145 insertions, 0 deletions
diff --git a/fs/umsdos/symlink.c b/fs/umsdos/symlink.c
new file mode 100644
index 000000000..1b1e561c2
--- /dev/null
+++ b/fs/umsdos/symlink.c
@@ -0,0 +1,145 @@
+/*
+ *  linux/fs/umsdos/file.c
+ *
+ *  Written 1992 by Jacques Gelinas
+ *	inspired from linux/fs/msdos/file.c Werner Almesberger
+ *
+ *  Extended MS-DOS regular file handling primitives
+ */
+
+#include <asm/segment.h>
+#include <asm/system.h>
+
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/msdos_fs.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/umsdos_fs.h>
+#include <linux/malloc.h>
+
+#define PRINTK(x)
+#define Printk(x)	printk x
+/*
+	Read the data associate with the symlink.
+	Return length read in buffer or  a negative error code.
+*/
+static int umsdos_readlink_x (
+	struct inode *inode,
+	char *buffer,
+	int (*msdos_read)(struct inode *, struct file *, char *, int),
+	int bufsiz)
+{
+	int ret = inode->i_size;
+	struct file filp;
+	filp.f_pos = 0;
+	filp.f_reada = 0;
+	if (ret > bufsiz) ret = bufsiz;
+	if ((*msdos_read) (inode, &filp, buffer,ret) != ret){
+		ret = -EIO;
+	}
+	return ret;
+}
+/*
+	Follow a symbolic link chain by calling open_namei recursively
+	until an inode is found.
+
+	Return 0 if ok, or a negative error code if not.
+*/
+static int UMSDOS_follow_link(
+	struct inode * dir,
+	struct inode * inode,
+	int flag,
+	int mode,
+	struct inode ** res_inode)
+{
+	int ret = -ELOOP;
+	*res_inode = NULL;
+	if (current->link_count < 5) {
+		char *path = (char*)kmalloc(PATH_MAX,GFP_KERNEL);
+		if (path == NULL){
+			ret = -ENOMEM;
+		}else{
+			if (!dir) {
+				dir = current->fs[1].root;
+				dir->i_count++;
+			}
+			if (!inode){
+				PRINTK (("symlink: inode = NULL\n"));
+				ret = -ENOENT;
+			}else if (!S_ISLNK(inode->i_mode)){
+				PRINTK (("symlink: Not ISLNK\n"));
+				*res_inode = inode;
+				inode = NULL;
+				ret = 0;
+			}else{
+				ret = umsdos_readlink_x (inode,path
+					,umsdos_file_read_kmem,PATH_MAX-1);
+				if (ret > 0){
+					path[ret] = '\0';
+					PRINTK (("follow :%s: %d ",path,ret));
+					iput(inode);
+					inode = NULL;
+					current->link_count++;
+					ret = open_namei(path,flag,mode,res_inode,dir);
+					current->link_count--;
+					dir = NULL;
+				}else{
+					ret = -EIO;
+				}
+			}
+			kfree (path);
+		}
+	}	
+	iput(inode);
+	iput(dir);
+	PRINTK (("follow_link ret %d\n",ret));
+	return ret;
+}
+
+static int UMSDOS_readlink(struct inode * inode, char * buffer, int buflen)
+{
+	int ret = -EINVAL;
+	if (S_ISLNK(inode->i_mode)) {
+		ret = umsdos_readlink_x (inode,buffer,msdos_file_read,buflen);
+	}
+	PRINTK (("readlink %d %x bufsiz %d\n",ret,inode->i_mode,buflen));
+	iput(inode);
+	return ret;
+	
+}
+
+static struct file_operations umsdos_symlink_operations = {
+	NULL,				/* lseek - default */
+	NULL,				/* read */
+	NULL,				/* write */
+	NULL,				/* readdir - bad */
+	NULL,				/* select - default */
+	NULL,				/* ioctl - default */
+	NULL,				/* mmap */
+	NULL,				/* no special open is needed */
+	NULL,				/* release */
+	NULL				/* fsync */
+};
+
+struct inode_operations umsdos_symlink_inode_operations = {
+	&umsdos_symlink_operations,	/* default file operations */
+	NULL,			/* create */
+	NULL,			/* lookup */
+	NULL,			/* link */
+	NULL,			/* unlink */
+	NULL,			/* symlink */
+	NULL,			/* mkdir */
+	NULL,			/* rmdir */
+	NULL,			/* mknod */
+	NULL,			/* rename */
+	UMSDOS_readlink,	/* readlink */
+	UMSDOS_follow_link,	/* follow_link */
+	NULL,			/* bmap */
+	NULL,			/* truncate */
+	NULL			/* permission */
+};
+
+
+