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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/readdir.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/readdir.c')
-rw-r--r--fs/readdir.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/fs/readdir.c b/fs/readdir.c
new file mode 100644
index 00000000000..b03579bc021
--- /dev/null
+++ b/fs/readdir.c
@@ -0,0 +1,300 @@
+/*
+ * linux/fs/readdir.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ */
+
+#include <linux/module.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/stat.h>
+#include <linux/file.h>
+#include <linux/smp_lock.h>
+#include <linux/fs.h>
+#include <linux/dirent.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/unistd.h>
+
+#include <asm/uaccess.h>
+
+int vfs_readdir(struct file *file, filldir_t filler, void *buf)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ int res = -ENOTDIR;
+ if (!file->f_op || !file->f_op->readdir)
+ goto out;
+
+ res = security_file_permission(file, MAY_READ);
+ if (res)
+ goto out;
+
+ down(&inode->i_sem);
+ res = -ENOENT;
+ if (!IS_DEADDIR(inode)) {
+ res = file->f_op->readdir(file, buf, filler);
+ file_accessed(file);
+ }
+ up(&inode->i_sem);
+out:
+ return res;
+}
+
+EXPORT_SYMBOL(vfs_readdir);
+
+/*
+ * Traditional linux readdir() handling..
+ *
+ * "count=1" is a special case, meaning that the buffer is one
+ * dirent-structure in size and that the code can't handle more
+ * anyway. Thus the special "fillonedir()" function for that
+ * case (the low-level handlers don't need to care about this).
+ */
+#define NAME_OFFSET(de) ((int) ((de)->d_name - (char __user *) (de)))
+#define ROUND_UP(x) (((x)+sizeof(long)-1) & ~(sizeof(long)-1))
+
+#ifdef __ARCH_WANT_OLD_READDIR
+
+struct old_linux_dirent {
+ unsigned long d_ino;
+ unsigned long d_offset;
+ unsigned short d_namlen;
+ char d_name[1];
+};
+
+struct readdir_callback {
+ struct old_linux_dirent __user * dirent;
+ int result;
+};
+
+static int fillonedir(void * __buf, const char * name, int namlen, loff_t offset,
+ ino_t ino, unsigned int d_type)
+{
+ struct readdir_callback * buf = (struct readdir_callback *) __buf;
+ struct old_linux_dirent __user * dirent;
+
+ if (buf->result)
+ return -EINVAL;
+ buf->result++;
+ dirent = buf->dirent;
+ if (!access_ok(VERIFY_WRITE, dirent,
+ (unsigned long)(dirent->d_name + namlen + 1) -
+ (unsigned long)dirent))
+ goto efault;
+ if ( __put_user(ino, &dirent->d_ino) ||
+ __put_user(offset, &dirent->d_offset) ||
+ __put_user(namlen, &dirent->d_namlen) ||
+ __copy_to_user(dirent->d_name, name, namlen) ||
+ __put_user(0, dirent->d_name + namlen))
+ goto efault;
+ return 0;
+efault:
+ buf->result = -EFAULT;
+ return -EFAULT;
+}
+
+asmlinkage long old_readdir(unsigned int fd, struct old_linux_dirent __user * dirent, unsigned int count)
+{
+ int error;
+ struct file * file;
+ struct readdir_callback buf;
+
+ error = -EBADF;
+ file = fget(fd);
+ if (!file)
+ goto out;
+
+ buf.result = 0;
+ buf.dirent = dirent;
+
+ error = vfs_readdir(file, fillonedir, &buf);
+ if (error >= 0)
+ error = buf.result;
+
+ fput(file);
+out:
+ return error;
+}
+
+#endif /* __ARCH_WANT_OLD_READDIR */
+
+/*
+ * New, all-improved, singing, dancing, iBCS2-compliant getdents()
+ * interface.
+ */
+struct linux_dirent {
+ unsigned long d_ino;
+ unsigned long d_off;
+ unsigned short d_reclen;
+ char d_name[1];
+};
+
+struct getdents_callback {
+ struct linux_dirent __user * current_dir;
+ struct linux_dirent __user * previous;
+ int count;
+ int error;
+};
+
+static int filldir(void * __buf, const char * name, int namlen, loff_t offset,
+ ino_t ino, unsigned int d_type)
+{
+ struct linux_dirent __user * dirent;
+ struct getdents_callback * buf = (struct getdents_callback *) __buf;
+ int reclen = ROUND_UP(NAME_OFFSET(dirent) + namlen + 2);
+
+ buf->error = -EINVAL; /* only used if we fail.. */
+ if (reclen > buf->count)
+ return -EINVAL;
+ dirent = buf->previous;
+ if (dirent) {
+ if (__put_user(offset, &dirent->d_off))
+ goto efault;
+ }
+ dirent = buf->current_dir;
+ if (__put_user(ino, &dirent->d_ino))
+ goto efault;
+ if (__put_user(reclen, &dirent->d_reclen))
+ goto efault;
+ if (copy_to_user(dirent->d_name, name, namlen))
+ goto efault;
+ if (__put_user(0, dirent->d_name + namlen))
+ goto efault;
+ if (__put_user(d_type, (char __user *) dirent + reclen - 1))
+ goto efault;
+ buf->previous = dirent;
+ dirent = (void __user *)dirent + reclen;
+ buf->current_dir = dirent;
+ buf->count -= reclen;
+ return 0;
+efault:
+ buf->error = -EFAULT;
+ return -EFAULT;
+}
+
+asmlinkage long sys_getdents(unsigned int fd, struct linux_dirent __user * dirent, unsigned int count)
+{
+ struct file * file;
+ struct linux_dirent __user * lastdirent;
+ struct getdents_callback buf;
+ int error;
+
+ error = -EFAULT;
+ if (!access_ok(VERIFY_WRITE, dirent, count))
+ goto out;
+
+ error = -EBADF;
+ file = fget(fd);
+ if (!file)
+ goto out;
+
+ buf.current_dir = dirent;
+ buf.previous = NULL;
+ buf.count = count;
+ buf.error = 0;
+
+ error = vfs_readdir(file, filldir, &buf);
+ if (error < 0)
+ goto out_putf;
+ error = buf.error;
+ lastdirent = buf.previous;
+ if (lastdirent) {
+ if (put_user(file->f_pos, &lastdirent->d_off))
+ error = -EFAULT;
+ else
+ error = count - buf.count;
+ }
+
+out_putf:
+ fput(file);
+out:
+ return error;
+}
+
+#define ROUND_UP64(x) (((x)+sizeof(u64)-1) & ~(sizeof(u64)-1))
+
+struct getdents_callback64 {
+ struct linux_dirent64 __user * current_dir;
+ struct linux_dirent64 __user * previous;
+ int count;
+ int error;
+};
+
+static int filldir64(void * __buf, const char * name, int namlen, loff_t offset,
+ ino_t ino, unsigned int d_type)
+{
+ struct linux_dirent64 __user *dirent;
+ struct getdents_callback64 * buf = (struct getdents_callback64 *) __buf;
+ int reclen = ROUND_UP64(NAME_OFFSET(dirent) + namlen + 1);
+
+ buf->error = -EINVAL; /* only used if we fail.. */
+ if (reclen > buf->count)
+ return -EINVAL;
+ dirent = buf->previous;
+ if (dirent) {
+ if (__put_user(offset, &dirent->d_off))
+ goto efault;
+ }
+ dirent = buf->current_dir;
+ if (__put_user(ino, &dirent->d_ino))
+ goto efault;
+ if (__put_user(0, &dirent->d_off))
+ goto efault;
+ if (__put_user(reclen, &dirent->d_reclen))
+ goto efault;
+ if (__put_user(d_type, &dirent->d_type))
+ goto efault;
+ if (copy_to_user(dirent->d_name, name, namlen))
+ goto efault;
+ if (__put_user(0, dirent->d_name + namlen))
+ goto efault;
+ buf->previous = dirent;
+ dirent = (void __user *)dirent + reclen;
+ buf->current_dir = dirent;
+ buf->count -= reclen;
+ return 0;
+efault:
+ buf->error = -EFAULT;
+ return -EFAULT;
+}
+
+asmlinkage long sys_getdents64(unsigned int fd, struct linux_dirent64 __user * dirent, unsigned int count)
+{
+ struct file * file;
+ struct linux_dirent64 __user * lastdirent;
+ struct getdents_callback64 buf;
+ int error;
+
+ error = -EFAULT;
+ if (!access_ok(VERIFY_WRITE, dirent, count))
+ goto out;
+
+ error = -EBADF;
+ file = fget(fd);
+ if (!file)
+ goto out;
+
+ buf.current_dir = dirent;
+ buf.previous = NULL;
+ buf.count = count;
+ buf.error = 0;
+
+ error = vfs_readdir(file, filldir64, &buf);
+ if (error < 0)
+ goto out_putf;
+ error = buf.error;
+ lastdirent = buf.previous;
+ if (lastdirent) {
+ typeof(lastdirent->d_off) d_off = file->f_pos;
+ error = -EFAULT;
+ if (__put_user(d_off, &lastdirent->d_off))
+ goto out_putf;
+ error = count - buf.count;
+ }
+
+out_putf:
+ fput(file);
+out:
+ return error;
+}