size.c
No OneTemporary
Actions

Size

1 KB

Referenced Files

None

Subscribers

None

size.c
View Options

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <stdint.h>
	#include <inttypes.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>
	#include <unistd.h>
	#include <errno.h>
	#include <sys/mount.h>

	#include "libgfs2.h"

	#ifndef BLKGETSIZE64
	#define BLKGETSIZE64 _IOR(0x12, 114, size_t)
	#endif

	/**
	* do_device_size - determine the size of a Linux block device
	* @device: the path to the device node
	*
	* Returns: -1 on error (with errno set), 0 on success (with @bytes set)
	*/

	static int
	do_device_size(int fd, uint64_t *bytes)
	{
	off_t off;
	#if 0
	int error;
	unsigned long size;

	error = ioctl(fd, BLKGETSIZE64, bytes); /* Size in bytes */
	if (!error)
	return 0;

	error = ioctl(fd, BLKGETSIZE, &size); /* Size in 512-byte blocks */
	if (!error) {
	*bytes = ((uint64_t) size) << 9;
	return 0;
	}
	#endif
	off = lseek(fd, 0, SEEK_END);
	if (off >= 0) {
	*bytes = off;
	return 0;
	}

	return -1;
	}

	/**
	* device_size - figure out a device's size
	* @fd: the file descriptor of a device
	* @bytes: the number of bytes the device holds
	*
	* Returns: -1 on error (with errno set), 0 on success (with @bytes set)
	*/

	int
	device_size(int fd, uint64_t *bytes)
	{
	struct stat st;
	int error;

	error = fstat(fd, &st);
	if (error)
	return error;

	if (S_ISREG(st.st_mode)) {
	*bytes = st.st_size;
	return 0;
	} else if (S_ISCHR(st.st_mode) \|\| S_ISBLK(st.st_mode))
	return do_device_size(fd, bytes);
	else if (S_ISDIR(st.st_mode))
	errno = EISDIR;
	else
	errno = EINVAL;

	return -1;
	}