getsize.c revision 9b7d811ddad946e728d9348a78cb06dee159df96 
1/*
2 * getsize.c --- get the size of a partition.
3 *
4 * Copyright (C) 1995, 1995 Theodore Ts'o.
5 * Copyright (C) 2003 VMware, Inc.
6 *
7 * Windows version of ext2fs_get_device_size by Chris Li, VMware.
8 *
9 * %Begin-Header%
10 * This file may be redistributed under the terms of the GNU Public
11 * License.
12 * %End-Header%
13 */
14
15#define _LARGEFILE_SOURCE
16#define _LARGEFILE64_SOURCE
17
18#include <stdio.h>
19#if HAVE_UNISTD_H
20#include <unistd.h>
21#endif
22#if HAVE_ERRNO_H
23#include <errno.h>
24#endif
25#include <fcntl.h>
26#ifdef HAVE_SYS_IOCTL_H
27#include <sys/ioctl.h>
28#endif
29#ifdef HAVE_LINUX_FD_H
30#include <linux/fd.h>
31#endif
32#ifdef HAVE_SYS_DISKLABEL_H
33#include <sys/disklabel.h>
34#endif
35#ifdef HAVE_SYS_DISK_H
36#ifdef HAVE_SYS_QUEUE_H
37#include <sys/queue.h> /* for LIST_HEAD */
38#endif
39#include <sys/disk.h>
40#endif
41#ifdef __linux__
42#include <sys/utsname.h>
43#endif
44#if HAVE_SYS_STAT_H
45#include <sys/stat.h>
46#endif
47
48#if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
49#define BLKGETSIZE _IO(0x12,96)	/* return device size */
50#endif
51
52#if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
53#define BLKGETSIZE64 _IOR(0x12,114,size_t)	/* return device size in bytes (u64 *arg) */
54#endif
55
56#ifdef APPLE_DARWIN
57#define BLKGETSIZE DKIOCGETBLOCKCOUNT32
58#endif /* APPLE_DARWIN */
59
60#include "ext2_fs.h"
61#include "ext2fs.h"
62
63#if defined(__CYGWIN__) || defined (WIN32)
64#include "windows.h"
65#include "winioctl.h"
66
67#if (_WIN32_WINNT >= 0x0500)
68#define HAVE_GET_FILE_SIZE_EX 1
69#endif
70
71errcode_t ext2fs_get_device_size(const char *file, int blocksize,
72				 blk_t *retblocks)
73{
74	HANDLE dev;
75	PARTITION_INFORMATION pi;
76	DISK_GEOMETRY gi;
77	DWORD retbytes;
78#ifdef HAVE_GET_FILE_SIZE_EX
79	LARGE_INTEGER filesize;
80#else
81	DWORD filesize;
82#endif /* HAVE_GET_FILE_SIZE_EX */
83
84	dev = CreateFile(file, GENERIC_READ,
85			 FILE_SHARE_READ | FILE_SHARE_WRITE ,
86                	 NULL,  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,  NULL);
87
88	if (dev == INVALID_HANDLE_VALUE)
89		return EBADF;
90	if (DeviceIoControl(dev, IOCTL_DISK_GET_PARTITION_INFO,
91			    &pi, sizeof(PARTITION_INFORMATION),
92			    &pi, sizeof(PARTITION_INFORMATION),
93			    &retbytes, NULL)) {
94
95		*retblocks = pi.PartitionLength.QuadPart / blocksize;
96
97	} else if (DeviceIoControl(dev, IOCTL_DISK_GET_DRIVE_GEOMETRY,
98				&gi, sizeof(DISK_GEOMETRY),
99				&gi, sizeof(DISK_GEOMETRY),
100				&retbytes, NULL)) {
101
102		*retblocks = gi.BytesPerSector *
103			     gi.SectorsPerTrack *
104			     gi.TracksPerCylinder *
105			     gi.Cylinders.QuadPart / blocksize;
106
107#ifdef HAVE_GET_FILE_SIZE_EX
108	} else if (GetFileSizeEx(dev, &filesize)) {
109		*retblocks = filesize.QuadPart / blocksize;
110	}
111#else
112	} else {
113		filesize = GetFileSize(dev, NULL);
114		if (INVALID_FILE_SIZE != filesize) {
115			*retblocks = filesize / blocksize;
116		}
117	}
118#endif /* HAVE_GET_FILE_SIZE_EX */
119
120	CloseHandle(dev);
121	return 0;
122}
123
124#else
125
126static int valid_offset (int fd, ext2_loff_t offset)
127{
128	char ch;
129
130	if (ext2fs_llseek (fd, offset, 0) < 0)
131		return 0;
132	if (read (fd, &ch, 1) < 1)
133		return 0;
134	return 1;
135}
136
137/*
138 * Returns the number of blocks in a partition
139 */
140errcode_t ext2fs_get_device_size(const char *file, int blocksize,
141				 blk_t *retblocks)
142{
143	int	fd, rc = 0;
144	int valid_blkgetsize64 = 1;
145#ifdef __linux__
146	struct 		utsname ut;
147#endif
148	unsigned long long size64;
149	unsigned long	size;
150	ext2_loff_t high, low;
151#ifdef FDGETPRM
152	struct floppy_struct this_floppy;
153#endif
154#ifdef HAVE_SYS_DISKLABEL_H
155	int part;
156	struct disklabel lab;
157	struct partition *pp;
158	char ch;
159#endif /* HAVE_SYS_DISKLABEL_H */
160
161#ifdef HAVE_OPEN64
162	fd = open64(file, O_RDONLY);
163#else
164	fd = open(file, O_RDONLY);
165#endif
166	if (fd < 0)
167		return errno;
168
169#ifdef DKIOCGETBLOCKCOUNT	/* For Apple Darwin */
170	if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0) {
171		if ((sizeof(*retblocks) < sizeof(unsigned long long))
172		    && ((size64 / (blocksize / 512)) > 0xFFFFFFFF))
173			return EFBIG;
174		*retblocks = size64 / (blocksize / 512);
175		goto out;
176	}
177#endif
178
179#ifdef BLKGETSIZE64
180#ifdef __linux__
181	if ((uname(&ut) == 0) &&
182	    ((ut.release[0] == '2') && (ut.release[1] == '.') &&
183	     (ut.release[2] < '6') && (ut.release[3] == '.')))
184		valid_blkgetsize64 = 0;
185#endif
186	if (valid_blkgetsize64 &&
187	    ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
188		if ((sizeof(*retblocks) < sizeof(unsigned long long)) &&
189		    ((size64 / blocksize) > 0xFFFFFFFF)) {
190			rc = EFBIG;
191			goto out;
192		}
193		*retblocks = size64 / blocksize;
194		goto out;
195	}
196#endif
197
198#ifdef BLKGETSIZE
199	if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
200		*retblocks = size / (blocksize / 512);
201		goto out;
202	}
203#endif
204
205#ifdef FDGETPRM
206	if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
207		*retblocks = this_floppy.size / (blocksize / 512);
208		goto out;
209	}
210#endif
211
212#ifdef HAVE_SYS_DISKLABEL_H
213#if defined(DIOCGMEDIASIZE)
214	{
215	    off_t ms;
216	    u_int bs;
217	    if (ioctl(fd, DIOCGMEDIASIZE, &ms) >= 0) {
218		*retblocks = ms / blocksize;
219		goto out;
220	    }
221	}
222#elif defined(DIOCGDINFO)
223	/* old disklabel interface */
224	part = strlen(file) - 1;
225	if (part >= 0) {
226		ch = file[part];
227		if (isdigit(ch))
228			part = 0;
229		else if (ch >= 'a' && ch <= 'h')
230			part = ch - 'a';
231		else
232			part = -1;
233	}
234	if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
235		pp = &lab.d_partitions[part];
236		if (pp->p_size) {
237			*retblocks = pp->p_size / (blocksize / 512);
238			goto out;
239		}
240	}
241#endif /* defined(DIOCG*) */
242#endif /* HAVE_SYS_DISKLABEL_H */
243
244	{
245#ifdef HAVE_FSTAT64
246		struct stat64   st;
247		if (fstat64(fd, &st) == 0)
248#else
249		struct stat	st;
250		if (fstat(fd, &st) == 0)
251#endif
252			if (S_ISREG(st.st_mode)) {
253				*retblocks = st.st_size / blocksize;
254				goto out;
255			}
256	}
257
258	/*
259	 * OK, we couldn't figure it out by using a specialized ioctl,
260	 * which is generally the best way.  So do binary search to
261	 * find the size of the partition.
262	 */
263	low = 0;
264	for (high = 1024; valid_offset (fd, high); high *= 2)
265		low = high;
266	while (low < high - 1)
267	{
268		const ext2_loff_t mid = (low + high) / 2;
269
270		if (valid_offset (fd, mid))
271			low = mid;
272		else
273			high = mid;
274	}
275	valid_offset (fd, 0);
276	size64 = low + 1;
277	if ((sizeof(*retblocks) < sizeof(unsigned long long))
278	    && ((size64 / blocksize) > 0xFFFFFFFF))
279		return EFBIG;
280	*retblocks = size64 / blocksize;
281out:
282	close(fd);
283	return rc;
284}
285
286#endif /* WIN32 */
287
288#ifdef DEBUG
289int main(int argc, char **argv)
290{
291	blk_t	blocks;
292	int	retval;
293
294	if (argc < 2) {
295		fprintf(stderr, "Usage: %s device\n", argv[0]);
296		exit(1);
297	}
298
299	retval = ext2fs_get_device_size(argv[1], 1024, &blocks);
300	if (retval) {
301		com_err(argv[0], retval,
302			"while calling ext2fs_get_device_size");
303		exit(1);
304	}
305	printf("Device %s has %d 1k blocks.\n", argv[1], blocks);
306	exit(0);
307}
308#endif
309