minix/lib/libsffs/stat.c
David van Moolenbroek ef7b484e5c Create SFFS library out of HGFS
This Shared Folders File System library (libsffs) now contains all the
file system logic originally in HGFS. The actual HGFS server code is
now a stub that passes on all the work to libsffs. The libhgfs library
is changed accordingly.
2012-04-09 18:08:26 +02:00

168 lines
4.2 KiB
C

/* This file contains file metadata retrieval and manipulation routines.
*
* The entry points into this file are:
* get_mode return a file's mode
* do_stat perform the STAT file system call
* do_chmod perform the CHMOD file system call
* do_utime perform the UTIME file system call
*
* Created:
* April 2009 (D.C. van Moolenbroek)
*/
#include "inc.h"
/*===========================================================================*
* get_mode *
*===========================================================================*/
mode_t get_mode(ino, mode)
struct inode *ino;
int mode;
{
/* Return the mode for an inode, given the inode and the retrieved mode.
*/
mode &= S_IRWXU;
mode = mode | (mode >> 3) | (mode >> 6);
if (IS_DIR(ino))
mode = S_IFDIR | (mode & sffs_params->p_dir_mask);
else
mode = S_IFREG | (mode & sffs_params->p_file_mask);
if (state.s_read_only)
mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
return mode;
}
/*===========================================================================*
* do_stat *
*===========================================================================*/
int do_stat()
{
/* Retrieve inode status.
*/
struct inode *ino;
struct sffs_attr attr;
struct stat stat;
char path[PATH_MAX];
ino_t ino_nr;
int r;
ino_nr = m_in.REQ_INODE_NR;
/* Don't increase the inode refcount: it's already open anyway */
if ((ino = find_inode(ino_nr)) == NULL)
return EINVAL;
attr.a_mask = SFFS_ATTR_MODE | SFFS_ATTR_SIZE | SFFS_ATTR_CRTIME |
SFFS_ATTR_ATIME | SFFS_ATTR_MTIME | SFFS_ATTR_CTIME;
if ((r = verify_inode(ino, path, &attr)) != OK)
return r;
memset(&stat, 0, sizeof(struct stat));
stat.st_dev = state.s_dev;
stat.st_ino = ino_nr;
stat.st_mode = get_mode(ino, attr.a_mode);
stat.st_uid = sffs_params->p_uid;
stat.st_gid = sffs_params->p_gid;
stat.st_rdev = NO_DEV;
if (cmp64u(attr.a_size, LONG_MAX) > 0)
stat.st_size = LONG_MAX;
else
stat.st_size = ex64lo(attr.a_size);
stat.st_atimespec = attr.a_atime;
stat.st_mtimespec = attr.a_mtime;
stat.st_ctimespec = attr.a_ctime;
stat.st_birthtimespec = attr.a_crtime;
stat.st_blocks = stat.st_size / S_BLKSIZE;
if (stat.st_size % S_BLKSIZE != 0)
stat.st_blocks += 1;
stat.st_blksize = BLOCK_SIZE;
/* We could make this more accurate by iterating over directory inodes'
* children, counting how many of those are directories as well.
* It's just not worth it.
*/
stat.st_nlink = 0;
if (ino->i_parent != NULL) stat.st_nlink++;
if (IS_DIR(ino)) {
stat.st_nlink++;
if (HAS_CHILDREN(ino)) stat.st_nlink++;
}
return sys_safecopyto(m_in.m_source, m_in.REQ_GRANT, 0,
(vir_bytes) &stat, sizeof(stat), D);
}
/*===========================================================================*
* do_chmod *
*===========================================================================*/
int do_chmod()
{
/* Change file mode.
*/
struct inode *ino;
char path[PATH_MAX];
struct sffs_attr attr;
int r;
if (state.s_read_only)
return EROFS;
if ((ino = find_inode(m_in.REQ_INODE_NR)) == NULL)
return EINVAL;
if ((r = verify_inode(ino, path, NULL)) != OK)
return r;
/* Set the new file mode. */
attr.a_mask = SFFS_ATTR_MODE;
attr.a_mode = m_in.REQ_MODE; /* no need to convert in this direction */
if ((r = sffs_table->t_setattr(path, &attr)) != OK)
return r;
/* We have no idea what really happened. Query for the mode again. */
if ((r = verify_path(path, ino, &attr, NULL)) != OK)
return r;
m_out.RES_MODE = get_mode(ino, attr.a_mode);
return OK;
}
/*===========================================================================*
* do_utime *
*===========================================================================*/
int do_utime()
{
/* Set file times.
*/
struct inode *ino;
char path[PATH_MAX];
struct sffs_attr attr;
int r;
if (state.s_read_only)
return EROFS;
if ((ino = find_inode(m_in.REQ_INODE_NR)) == NULL)
return EINVAL;
if ((r = verify_inode(ino, path, NULL)) != OK)
return r;
attr.a_mask = SFFS_ATTR_ATIME | SFFS_ATTR_MTIME;
attr.a_atime.tv_sec = m_in.REQ_ACTIME;
attr.a_atime.tv_nsec = 0;
attr.a_mtime.tv_sec = m_in.REQ_MODTIME;
attr.a_mtime.tv_nsec = 0;
return sffs_table->t_setattr(path, &attr);
}