/*

   * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)

   * Licensed under the GPL
   */

  #include <stdio.h>

  #include <stddef.h>
  #include <unistd.h>

  #include <dirent.h>
  #include <errno.h>

  #include <fcntl.h>

  #include <string.h>
  #include <sys/stat.h>
  #include <sys/time.h>

  #include <sys/types.h>

  #include <sys/vfs.h>

  #include <sys/syscall.h>

  #include "hostfs.h"

  #include <utime.h>

  static void stat64_to_hostfs(const struct stat64 *buf, struct hostfs_stat *p)
  {
  	p->ino = buf->st_ino;
  	p->mode = buf->st_mode;
  	p->nlink = buf->st_nlink;
  	p->uid = buf->st_uid;
  	p->gid = buf->st_gid;
  	p->size = buf->st_size;
  	p->atime.tv_sec = buf->st_atime;
  	p->atime.tv_nsec = 0;
  	p->ctime.tv_sec = buf->st_ctime;
  	p->ctime.tv_nsec = 0;
  	p->mtime.tv_sec = buf->st_mtime;
  	p->mtime.tv_nsec = 0;
  	p->blksize = buf->st_blksize;
  	p->blocks = buf->st_blocks;
  	p->maj = os_major(buf->st_rdev);
  	p->min = os_minor(buf->st_rdev);
  }
  
  int stat_file(const char *path, struct hostfs_stat *p, int fd)

  {
  	struct stat64 buf;

  	if (fd >= 0) {

  		if (fstat64(fd, &buf) < 0)

  			return -errno;

  	} else if (lstat64(path, &buf) < 0) {

  		return -errno;

  	}

  	stat64_to_hostfs(&buf, p);

  	return 0;

  }

  int access_file(char *path, int r, int w, int x)
  {
  	int mode = 0;

  	if (r)
  		mode = R_OK;
  	if (w)
  		mode |= W_OK;
  	if (x)
  		mode |= X_OK;
  	if (access(path, mode) != 0)

  		return -errno;
  	else return 0;

  }
  
  int open_file(char *path, int r, int w, int append)
  {
  	int mode = 0, fd;

  	if (r && !w)

  		mode = O_RDONLY;

  	else if (!r && w)

  		mode = O_WRONLY;

  	else if (r && w)

  		mode = O_RDWR;
  	else panic("Impossible mode in open_file");

  	if (append)

  		mode |= O_APPEND;
  	fd = open64(path, mode);

  	if (fd < 0)

  		return -errno;
  	else return fd;

  }
  
  void *open_dir(char *path, int *err_out)
  {
  	DIR *dir;
  
  	dir = opendir(path);
  	*err_out = errno;

  	return dir;

  }

  void seek_dir(void *stream, unsigned long long pos)
  {
  	DIR *dir = stream;
  
  	seekdir(dir, pos);
  }
  
  char *read_dir(void *stream, unsigned long long *pos_out,

  	       unsigned long long *ino_out, int *len_out,
  	       unsigned int *type_out)

  {
  	DIR *dir = stream;
  	struct dirent *ent;

  	ent = readdir(dir);

  	if (ent == NULL)

  		return NULL;

  	*len_out = strlen(ent->d_name);
  	*ino_out = ent->d_ino;

  	*type_out = ent->d_type;

  	*pos_out = ent->d_off;

  	return ent->d_name;

  }
  
  int read_file(int fd, unsigned long long *offset, char *buf, int len)
  {
  	int n;
  
  	n = pread64(fd, buf, len, *offset);

  	if (n < 0)

  		return -errno;

  	*offset += n;

  	return n;

  }
  
  int write_file(int fd, unsigned long long *offset, const char *buf, int len)
  {
  	int n;
  
  	n = pwrite64(fd, buf, len, *offset);

  	if (n < 0)

  		return -errno;

  	*offset += n;

  	return n;

  }
  
  int lseek_file(int fd, long long offset, int whence)
  {
  	int ret;
  
  	ret = lseek64(fd, offset, whence);

  	if (ret < 0)

  		return -errno;
  	return 0;

  }

  int fsync_file(int fd, int datasync)
  {
  	int ret;
  	if (datasync)
  		ret = fdatasync(fd);
  	else
  		ret = fsync(fd);
  
  	if (ret < 0)
  		return -errno;
  	return 0;
  }

  int replace_file(int oldfd, int fd)
  {
  	return dup2(oldfd, fd);
  }

  void close_file(void *stream)
  {
  	close(*((int *) stream));
  }
  
  void close_dir(void *stream)
  {
  	closedir(stream);
  }

  int file_create(char *name, int mode)

  {

  	int fd;

  	fd = open64(name, O_CREAT | O_RDWR, mode);

  	if (fd < 0)

  		return -errno;
  	return fd;

  }

  int set_attr(const char *file, struct hostfs_iattr *attrs, int fd)

  {

  	struct hostfs_stat st;

  	struct timeval times[2];

  	int err, ma;

  	if (attrs->ia_valid & HOSTFS_ATTR_MODE) {
  		if (fd >= 0) {
  			if (fchmod(fd, attrs->ia_mode) != 0)

  				return -errno;

  		} else if (chmod(file, attrs->ia_mode) != 0) {

  			return -errno;

  		}

  	}

  	if (attrs->ia_valid & HOSTFS_ATTR_UID) {
  		if (fd >= 0) {
  			if (fchown(fd, attrs->ia_uid, -1))

  				return -errno;

  		} else if (chown(file, attrs->ia_uid, -1)) {

  			return -errno;

  		}

  	}

  	if (attrs->ia_valid & HOSTFS_ATTR_GID) {
  		if (fd >= 0) {
  			if (fchown(fd, -1, attrs->ia_gid))

  				return -errno;

  		} else if (chown(file, -1, attrs->ia_gid)) {

  			return -errno;

  		}

  	}

  	if (attrs->ia_valid & HOSTFS_ATTR_SIZE) {
  		if (fd >= 0) {
  			if (ftruncate(fd, attrs->ia_size))

  				return -errno;

  		} else if (truncate(file, attrs->ia_size)) {

  			return -errno;

  		}

  	}

  	/*
  	 * Update accessed and/or modified time, in two parts: first set

  	 * times according to the changes to perform, and then call futimes()

  	 * or utimes() to apply them.
  	 */

  	ma = (HOSTFS_ATTR_ATIME_SET | HOSTFS_ATTR_MTIME_SET);
  	if (attrs->ia_valid & ma) {

  		err = stat_file(file, &st, fd);

  		if (err != 0)
  			return err;

  		times[0].tv_sec = st.atime.tv_sec;
  		times[0].tv_usec = st.atime.tv_nsec / 1000;
  		times[1].tv_sec = st.mtime.tv_sec;
  		times[1].tv_usec = st.mtime.tv_nsec / 1000;

  
  		if (attrs->ia_valid & HOSTFS_ATTR_ATIME_SET) {
  			times[0].tv_sec = attrs->ia_atime.tv_sec;

  			times[0].tv_usec = attrs->ia_atime.tv_nsec / 1000;

  		}

  		if (attrs->ia_valid & HOSTFS_ATTR_MTIME_SET) {
  			times[1].tv_sec = attrs->ia_mtime.tv_sec;

  			times[1].tv_usec = attrs->ia_mtime.tv_nsec / 1000;

  		}
  
  		if (fd >= 0) {
  			if (futimes(fd, times) != 0)

  				return -errno;

  		} else if (utimes(file, times) != 0) {

  			return -errno;

  		}
  	}

  	/* Note: ctime is not handled */

  	if (attrs->ia_valid & (HOSTFS_ATTR_ATIME | HOSTFS_ATTR_MTIME)) {

  		err = stat_file(file, &st, fd);
  		attrs->ia_atime = st.atime;
  		attrs->ia_mtime = st.mtime;

  		if (err != 0)

  			return err;

  	}

  	return 0;

  }
  
  int make_symlink(const char *from, const char *to)
  {
  	int err;
  
  	err = symlink(to, from);

  	if (err)

  		return -errno;
  	return 0;

  }
  
  int unlink_file(const char *file)
  {
  	int err;
  
  	err = unlink(file);

  	if (err)

  		return -errno;
  	return 0;

  }
  
  int do_mkdir(const char *file, int mode)
  {
  	int err;
  
  	err = mkdir(file, mode);

  	if (err)

  		return -errno;
  	return 0;

  }
  
  int do_rmdir(const char *file)
  {
  	int err;
  
  	err = rmdir(file);

  	if (err)

  		return -errno;
  	return 0;

  }

  int do_mknod(const char *file, int mode, unsigned int major, unsigned int minor)

  {
  	int err;

  	err = mknod(file, mode, os_makedev(major, minor));

  	if (err)

  		return -errno;
  	return 0;

  }
  
  int link_file(const char *to, const char *from)
  {
  	int err;
  
  	err = link(to, from);

  	if (err)

  		return -errno;
  	return 0;

  }

  int hostfs_do_readlink(char *file, char *buf, int size)

  {
  	int n;
  
  	n = readlink(file, buf, size);

  	if (n < 0)

  		return -errno;

  	if (n < size)

  		buf[n] = '\0';

  	return n;

  }
  
  int rename_file(char *from, char *to)
  {
  	int err;
  
  	err = rename(from, to);

  	if (err < 0)

  		return -errno;
  	return 0;

  }

  int rename2_file(char *from, char *to, unsigned int flags)
  {
  	int err;
  
  #ifndef SYS_renameat2
  #  ifdef __x86_64__
  #    define SYS_renameat2 316
  #  endif
  #  ifdef __i386__
  #    define SYS_renameat2 353
  #  endif
  #endif
  
  #ifdef SYS_renameat2
  	err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
  	if (err < 0) {
  		if (errno != ENOSYS)
  			return -errno;
  		else
  			return -EINVAL;
  	}
  	return 0;
  #else
  	return -EINVAL;
  #endif
  }

  int do_statfs(char *root, long *bsize_out, long long *blocks_out,
  	      long long *bfree_out, long long *bavail_out,
  	      long long *files_out, long long *ffree_out,

  	      void *fsid_out, int fsid_size, long *namelen_out)

  {
  	struct statfs64 buf;
  	int err;
  
  	err = statfs64(root, &buf);

  	if (err < 0)

  		return -errno;

  	*bsize_out = buf.f_bsize;
  	*blocks_out = buf.f_blocks;
  	*bfree_out = buf.f_bfree;
  	*bavail_out = buf.f_bavail;
  	*files_out = buf.f_files;
  	*ffree_out = buf.f_ffree;
  	memcpy(fsid_out, &buf.f_fsid,
  	       sizeof(buf.f_fsid) > fsid_size ? fsid_size :
  	       sizeof(buf.f_fsid));
  	*namelen_out = buf.f_namelen;

  	return 0;

  }