arch/um/fs/hostfs/host_file.c

/* 
 * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <dirent.h>
#include <utime.h>
#include <sys/vfs.h>
#include "os.h"
#include "user.h"
#include "hostfs.h"

extern int append;

char *get_path(const char *path[], char *buf, int size)
{
	const char **s;
	char *p;
	int new = 1;

	for(s = path; *s != NULL; s++){
		new += strlen(*s);
		if((*(s + 1) != NULL) && (strlen(*s) > 0) && 
		   ((*s)[strlen(*s) - 1] != '/'))
			new++;
	}

	if(new > size){
		buf = um_kmalloc(new);
		if(buf == NULL)
			return(NULL);
	}

	p = buf;
	for(s = path; *s != NULL; s++){
		strcpy(p, *s);
		p += strlen(*s);
		if((*(s + 1) != NULL) && (strlen(*s) > 0) && 
		   ((*s)[strlen(*s) - 1] != '/'))
			strcpy(p++, "/");
	}
		
	return(buf);
}

void free_path(const char *buf, char *tmp)
{
	if((buf != tmp) && (buf != NULL))
		kfree((char *) buf);
}

int host_open_file(const char *path[], int r, int w)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	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 {
	  	printk("Impossible mode in host_open_file - r = %d, w = %d", 
		       r, w);
		return(-EINVAL);
	}

	if(append)
		mode |= O_APPEND;

	fd = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;
	
	fd = open64(file, mode);
	if(fd < 0) 
		fd = -errno;
 out:
	free_path(file, tmp);
	return(fd);
}

void *host_open_dir(const char *path[], int *err_out)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	DIR *dir = NULL;

	*err_out = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;
	
	dir = opendir(file);
	*err_out = errno;
 out:
	free_path(file, tmp);
	return(dir);
}

char *host_read_dir(void *stream, unsigned long long *pos, 
		    unsigned long long *ino_out, int *len_out)
{
	DIR *dir = stream;
	struct dirent *ent;

	seekdir(dir, *pos);
	ent = readdir(dir);
	if(ent == NULL) return(NULL);
	*len_out = strlen(ent->d_name);
	*ino_out = ent->d_ino;
	*pos = telldir(dir);
	return(ent->d_name);
}

void host_close_dir(void *stream)
{
	closedir(stream);
}

int host_file_type(const char *path[], int *rdev)
{
	char tmp[HOSTFS_BUFSIZE], *file;
 	struct stat64 buf;
	int ret;

	ret = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	if(lstat64(file, &buf) < 0){
		ret = -errno;
		goto out;
	}

	if(rdev != NULL) 
		*rdev = buf.st_rdev;

	if(S_ISDIR(buf.st_mode)) ret = OS_TYPE_DIR;
	else if(S_ISLNK(buf.st_mode)) ret = OS_TYPE_SYMLINK;
	else if(S_ISCHR(buf.st_mode)) ret = OS_TYPE_CHARDEV;
	else if(S_ISBLK(buf.st_mode)) ret = OS_TYPE_BLOCKDEV;
	else if(S_ISFIFO(buf.st_mode))ret = OS_TYPE_FIFO;
	else if(S_ISSOCK(buf.st_mode))ret = OS_TYPE_SOCK;
	else ret = OS_TYPE_FILE;
 out:
	free_path(file, tmp);
	return(ret);
}

int host_file_create(const char *path[], int ur, int uw, int ux, 
		     int gr, int gw, int gx, int or, int ow, int ox)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int mode = 0, fd;

	mode |= ur ? S_IRUSR : 0;
	mode |= uw ? S_IWUSR : 0;
	mode |= ux ? S_IXUSR : 0;
	mode |= gr ? S_IRGRP : 0;
	mode |= gw ? S_IWGRP : 0;
	mode |= gx ? S_IXGRP : 0;
	mode |= or ? S_IROTH : 0;
	mode |= ow ? S_IWOTH : 0;
	mode |= ox ? S_IXOTH : 0;

	fd = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	fd = open64(file, O_CREAT | O_RDWR, mode);
 out:
	free_path(file, tmp);
	return(fd);
}

static int do_stat_file(const char *path, int *dev_out, 
			unsigned long long *inode_out, int *mode_out, 
			int *nlink_out, int *uid_out, int *gid_out, 
			unsigned long long *size_out, unsigned long *atime_out,
			unsigned long *mtime_out, unsigned long *ctime_out,
			int *blksize_out, unsigned long long *blocks_out)
{
	struct stat64 buf;

	if(lstat64(path, &buf) < 0)
		return(-errno);

	if(dev_out != NULL) *dev_out = buf.st_dev;

	/* See the Makefile for why STAT64_INO_FIELD is passed in
	 * by the build
	 */
	if(inode_out != NULL) *inode_out = buf.STAT64_INO_FIELD;
	if(mode_out != NULL) *mode_out = buf.st_mode;
	if(nlink_out != NULL) *nlink_out = buf.st_nlink;
	if(uid_out != NULL) *uid_out = buf.st_uid;
	if(gid_out != NULL) *gid_out = buf.st_gid;
	if(size_out != NULL) *size_out = buf.st_size;
	if(atime_out != NULL) *atime_out = buf.st_atime;
	if(mtime_out != NULL) *mtime_out = buf.st_mtime;
	if(ctime_out != NULL) *ctime_out = buf.st_ctime;
	if(blksize_out != NULL) *blksize_out = buf.st_blksize;
	if(blocks_out != NULL) *blocks_out = buf.st_blocks;

	return(0);
}

int host_stat_file(const char *path[], int *dev_out, 
		   unsigned long long *inode_out, int *mode_out, 
		   int *nlink_out, int *uid_out, int *gid_out, 
		   unsigned long long *size_out, unsigned long *atime_out,
		   unsigned long *mtime_out, unsigned long *ctime_out,
		   int *blksize_out, unsigned long long *blocks_out)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int err;

	err = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	err = do_stat_file(file, dev_out, inode_out, mode_out, nlink_out,
			   uid_out, gid_out, size_out, atime_out, mtime_out,
			   ctime_out, blksize_out, blocks_out);
 out:
	free_path(file, tmp);
	return(err);
}

int host_set_attr(const char *path[], struct hostfs_iattr *attrs)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	struct utimbuf buf;
	int err = 0, ma;

	if(append && (attrs->ia_valid & HOSTFS_ATTR_SIZE))
		return(-EPERM);

	err = -ENOMEM;
	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	if(attrs->ia_valid & HOSTFS_ATTR_MODE){
		if(chmod(file, attrs->ia_mode) != 0){
			err = -errno;
			goto out;
		}
	}
	if(attrs->ia_valid & HOSTFS_ATTR_UID){
		if(chown(file, attrs->ia_uid, -1)){
			err = -errno;
			goto out;
		}
	}
	if(attrs->ia_valid & HOSTFS_ATTR_GID){
		if(chown(file, -1, attrs->ia_gid)){
			err = -errno;
			goto out;
		}
	}
	if(attrs->ia_valid & HOSTFS_ATTR_SIZE){
		if(truncate(file, attrs->ia_size)){
			err = -errno;
			goto out;
		}
	}
	ma = HOSTFS_ATTR_ATIME_SET | HOSTFS_ATTR_MTIME_SET;
	if((attrs->ia_valid & ma) == ma){
		buf.actime = attrs->ia_atime;
		buf.modtime = attrs->ia_mtime;
		if(utime(file, &buf) != 0){
			err = -errno;
			goto out;
		}
	}
	else {
		if(attrs->ia_valid & HOSTFS_ATTR_ATIME_SET){
			err = do_stat_file(file, NULL, NULL, NULL, NULL, NULL, 
					   NULL, NULL, NULL, &buf.modtime, 
					   NULL, NULL, NULL);
			if(err != 0)
				goto out;
			buf.actime = attrs->ia_atime;
			if(utime(file, &buf) != 0){
				err = -errno;
				goto out;
			}
		}
		if(attrs->ia_valid & HOSTFS_ATTR_MTIME_SET){
			err = do_stat_file(file, NULL, NULL, NULL, NULL, NULL, 
					   NULL, NULL, &buf.actime, NULL, 
					   NULL, NULL, NULL);
			if(err != 0)
				goto out;
			buf.modtime = attrs->ia_mtime;
			if(utime(file, &buf) != 0){
				err = -errno;
				goto out;
			}
		}
	}
	if(attrs->ia_valid & HOSTFS_ATTR_CTIME) ;
	if(attrs->ia_valid & (HOSTFS_ATTR_ATIME | HOSTFS_ATTR_MTIME)){
		err = do_stat_file(file, NULL, NULL, NULL, NULL, NULL, 
				   NULL, NULL, &attrs->ia_atime, 
				   &attrs->ia_mtime, NULL, NULL, NULL);
		if(err != 0)
			goto out;
	}

	err = 0;
 out:
	free_path(file, tmp);
	return(err);
}

int host_make_symlink(const char *from[], const char *to)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int err = -ENOMEM;

	file = get_path(from, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;
	
	err = symlink(to, file);
	if(err) 
		err = -errno;
 out:
	free_path(file, tmp);
	return(err);
}

int host_unlink_file(const char *path[])
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int err = -ENOMEM;

	if(append)
		return(-EPERM);

	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	err = unlink(file);
	if(err) 
		err = -errno;
 out:
	free_path(file, tmp);
	return(err);
}

int host_mkdir(const char *path[], int mode)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int err = -ENOMEM;

	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	err = mkdir(file, mode);
	if(err) 
		err = -errno;
 out:
	free_path(file, tmp);
	return(err);
}

int host_rmdir(const char *path[])
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int err = -ENOMEM;

	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	err = rmdir(file);
	if(err) 
		err = -errno;
 out:
	free_path(file, tmp);
	return(err);
}

int host_link_file(const char *to[], const char *from[])
{
	char from_tmp[HOSTFS_BUFSIZE], *f, to_tmp[HOSTFS_BUFSIZE], *t;
	int err = -ENOMEM;

	f = get_path(from, from_tmp, sizeof(from_tmp));
	t = get_path(to, to_tmp, sizeof(to_tmp));
	if((f == NULL) || (t == NULL))
		goto out;

	err = link(t, f);
	if(err) 
		err = -errno;
 out:
	free_path(f, from_tmp);
	free_path(t, to_tmp);
	return(err);
}

int host_readlink(const char *path[], char *buf, int size)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	int n = -ENOMEM;

	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	n = readlink(file, buf, size);
	if(n < 0) 
		n = -errno;
	if(n < size) 
		buf[n] = '\0';
 out:
	free_path(file, tmp);
	return(n);
}

int host_rename_file(const char *from[], const char *to[])
{
	char from_tmp[HOSTFS_BUFSIZE], *f, to_tmp[HOSTFS_BUFSIZE], *t;
	int err = -ENOMEM;

	f = get_path(from, from_tmp, sizeof(from_tmp));
	t = get_path(to, to_tmp, sizeof(to_tmp));
	if((f == NULL) || (t == NULL))
		goto out;

	err = rename(f, t);
	if(err < 0) 
		err = -errno;
 out:
	free_path(f, from_tmp);
	free_path(t, to_tmp);
	return(err);
}

int host_statfs(const char *path[], 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, long *spare_out)
{
	char tmp[HOSTFS_BUFSIZE], *file;
	struct statfs64 buf;
	int err = -ENOMEM;

	file = get_path(path, tmp, sizeof(tmp));
	if(file == NULL)
		goto out;

	err = statfs64(file, &buf);
	if(err < 0){
		err = -errno;
		goto out;
	}
	*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;
	spare_out[0] = buf.f_spare[0];
	spare_out[1] = buf.f_spare[1];
	spare_out[2] = buf.f_spare[2];
	spare_out[3] = buf.f_spare[3];
	spare_out[4] = buf.f_spare[4];
	spare_out[5] = buf.f_spare[5];
 out:
	free_path(file, tmp);
	return(err);
}

char *generic_host_read_dir(void *stream, unsigned long long *pos, 
			    unsigned long long *ino_out, int *len_out, 
			    void *mount)
{
	return(host_read_dir(stream, pos, ino_out, len_out));
}

int generic_host_read_file(int fd, unsigned long long offset, char *buf,
			   int len, void *mount)
{
	return(host_read_file(fd, offset, buf, len));
}

int generic_host_write_file(int fd, unsigned long long offset, const char *buf,
			    int len, void *mount)
{
	return(host_write_file(fd, offset, buf, len));
}

void generic_host_close_file(void *stream, unsigned long long size, void *mount)
{
	return(host_close_file(stream));
}

void generic_host_close_dir(void *stream, void *mount)
{
	return(host_close_dir(stream));
}

int generic_host_truncate_file(int fd, __u64 size, void *m)
{
	return(os_truncate_fd(fd, size));
}

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-file-style: "linux"
 * End:
 */