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 Library
11  * General Public License, version 2.
12  * %End-Header%
13  */
14 
15 #ifndef _LARGEFILE_SOURCE
16 #define _LARGEFILE_SOURCE
17 #endif
18 #ifndef _LARGEFILE64_SOURCE
19 #define _LARGEFILE64_SOURCE
20 #endif
21 
22 #include "config.h"
23 #include <stdio.h>
24 #if HAVE_UNISTD_H
25 #include <unistd.h>
26 #endif
27 #if HAVE_ERRNO_H
28 #include <errno.h>
29 #endif
30 #include <fcntl.h>
31 #ifdef HAVE_SYS_IOCTL_H
32 #include <sys/ioctl.h>
33 #endif
34 #ifdef HAVE_LINUX_FD_H
35 #include <linux/fd.h>
36 #endif
37 #ifdef HAVE_SYS_DISKLABEL_H
38 #include <sys/disklabel.h>
39 #endif
40 #ifdef HAVE_SYS_DISK_H
41 #include <sys/disk.h>
42 #endif
43 #ifdef __linux__
44 #include <sys/utsname.h>
45 #endif
46 #if HAVE_SYS_STAT_H
47 #include <sys/stat.h>
48 #endif
49 #include <ctype.h>
50 
51 #if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
52 #define BLKGETSIZE _IO(0x12,96)	/* return device size */
53 #endif
54 
55 #if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
56 #define BLKGETSIZE64 _IOR(0x12,114,size_t)	/* return device size in bytes (u64 *arg) */
57 #endif
58 
59 #ifdef APPLE_DARWIN
60 #define BLKGETSIZE DKIOCGETBLOCKCOUNT32
61 #endif /* APPLE_DARWIN */
62 
63 #include "ext2_fs.h"
64 #include "ext2fs.h"
65 
66 #if defined(__CYGWIN__) || defined (WIN32)
67 #include "windows.h"
68 #include "winioctl.h"
69 
70 #if (_WIN32_WINNT >= 0x0500)
71 #define HAVE_GET_FILE_SIZE_EX 1
72 #endif
73 
ext2fs_get_device_size2(const char * file,int blocksize,blk64_t * retblocks)74 errcode_t ext2fs_get_device_size2(const char *file, int blocksize,
75 				  blk64_t *retblocks)
76 {
77 	HANDLE dev;
78 	PARTITION_INFORMATION pi;
79 	DISK_GEOMETRY gi;
80 	DWORD retbytes;
81 #ifdef HAVE_GET_FILE_SIZE_EX
82 	LARGE_INTEGER filesize;
83 #else
84 	DWORD filesize;
85 #endif /* HAVE_GET_FILE_SIZE_EX */
86 
87 	dev = CreateFile(file, GENERIC_READ,
88 			 FILE_SHARE_READ | FILE_SHARE_WRITE ,
89                 	 NULL,  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,  NULL);
90 
91 	if (dev == INVALID_HANDLE_VALUE)
92 		return EBADF;
93 	if (DeviceIoControl(dev, IOCTL_DISK_GET_PARTITION_INFO,
94 			    &pi, sizeof(PARTITION_INFORMATION),
95 			    &pi, sizeof(PARTITION_INFORMATION),
96 			    &retbytes, NULL)) {
97 
98 		*retblocks = pi.PartitionLength.QuadPart / blocksize;
99 
100 	} else if (DeviceIoControl(dev, IOCTL_DISK_GET_DRIVE_GEOMETRY,
101 				&gi, sizeof(DISK_GEOMETRY),
102 				&gi, sizeof(DISK_GEOMETRY),
103 				&retbytes, NULL)) {
104 
105 		*retblocks = gi.BytesPerSector *
106 			     gi.SectorsPerTrack *
107 			     gi.TracksPerCylinder *
108 			     gi.Cylinders.QuadPart / blocksize;
109 
110 #ifdef HAVE_GET_FILE_SIZE_EX
111 	} else if (GetFileSizeEx(dev, &filesize)) {
112 		*retblocks = filesize.QuadPart / blocksize;
113 	}
114 #else
115 	} else {
116 		filesize = GetFileSize(dev, NULL);
117 		if (INVALID_FILE_SIZE != filesize) {
118 			*retblocks = filesize / blocksize;
119 		}
120 	}
121 #endif /* HAVE_GET_FILE_SIZE_EX */
122 
123 	CloseHandle(dev);
124 	return 0;
125 }
126 
127 #else
128 
valid_offset(int fd,ext2_loff_t offset)129 static int valid_offset (int fd, ext2_loff_t offset)
130 {
131 	char ch;
132 
133 	if (ext2fs_llseek (fd, offset, 0) < 0)
134 		return 0;
135 	if (read (fd, &ch, 1) < 1)
136 		return 0;
137 	return 1;
138 }
139 
140 /*
141  * Returns the number of blocks in a partition
142  */
ext2fs_get_device_size2(const char * file,int blocksize,blk64_t * retblocks)143 errcode_t ext2fs_get_device_size2(const char *file, int blocksize,
144 				  blk64_t *retblocks)
145 {
146 	int	fd, rc = 0;
147 	unsigned long long size64;
148 	ext2_loff_t high, low;
149 
150 	fd = ext2fs_open_file(file, O_RDONLY, 0);
151 	if (fd < 0)
152 		return errno;
153 
154 #if defined DKIOCGETBLOCKCOUNT && defined DKIOCGETBLOCKSIZE	/* For Apple Darwin */
155 	unsigned int size;
156 
157 	if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0 &&
158 	    ioctl(fd, DKIOCGETBLOCKSIZE, &size) >= 0) {
159 		*retblocks = size64 * size / blocksize;
160 		goto out;
161 	}
162 #endif
163 
164 #ifdef BLKGETSIZE64
165 	{
166 		int valid_blkgetsize64 = 1;
167 #ifdef __linux__
168 		struct utsname ut;
169 
170 		if ((uname(&ut) == 0) &&
171 		    ((ut.release[0] == '2') && (ut.release[1] == '.') &&
172 		     (ut.release[2] < '6') && (ut.release[3] == '.')))
173 			valid_blkgetsize64 = 0;
174 #endif
175 		if (valid_blkgetsize64 &&
176 		    ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
177 			*retblocks = size64 / blocksize;
178 			goto out;
179 		}
180 	}
181 #endif /* BLKGETSIZE64 */
182 
183 #ifdef BLKGETSIZE
184 	{
185 		unsigned long	size;
186 
187 		if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
188 			*retblocks = size / (blocksize / 512);
189 			goto out;
190 		}
191 	}
192 #endif
193 
194 #ifdef FDGETPRM
195 	{
196 		struct floppy_struct this_floppy;
197 
198 		if (ioctl(fd, FDGETPRM, &this_floppy) >= 0) {
199 			*retblocks = this_floppy.size / (blocksize / 512);
200 			goto out;
201 		}
202 	}
203 #endif
204 
205 #ifdef HAVE_SYS_DISKLABEL_H
206 	{
207 		int part;
208 		struct disklabel lab;
209 		struct partition *pp;
210 		char ch;
211 
212 #if defined(DIOCGMEDIASIZE)
213 		{
214 			off_t ms;
215 			u_int bs;
216 			if (ioctl(fd, DIOCGMEDIASIZE, &ms) >= 0) {
217 				*retblocks = ms / blocksize;
218 				goto out;
219 			}
220 		}
221 #elif defined(DIOCGDINFO)
222 		/* old disklabel interface */
223 		part = strlen(file) - 1;
224 		if (part >= 0) {
225 			ch = file[part];
226 			if (isdigit(ch))
227 				part = 0;
228 			else if (ch >= 'a' && ch <= 'h')
229 				part = ch - 'a';
230 			else
231 				part = -1;
232 		}
233 		if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
234 			pp = &lab.d_partitions[part];
235 			if (pp->p_size) {
236 				*retblocks = pp->p_size / (blocksize / 512);
237 				goto out;
238 			}
239 		}
240 #endif /* defined(DIOCG*) */
241 	}
242 #endif /* HAVE_SYS_DISKLABEL_H */
243 
244 	{
245 		ext2fs_struct_stat st;
246 
247 		if (ext2fs_fstat(fd, &st) == 0)
248 			if (S_ISREG(st.st_mode)) {
249 				*retblocks = st.st_size / blocksize;
250 				goto out;
251 			}
252 	}
253 
254 	/*
255 	 * OK, we couldn't figure it out by using a specialized ioctl,
256 	 * which is generally the best way.  So do binary search to
257 	 * find the size of the partition.
258 	 */
259 	low = 0;
260 	for (high = 1024; valid_offset(fd, high); high *= 2)
261 		low = high;
262 	while (low < high - 1) {
263 		const ext2_loff_t mid = (low + high) / 2;
264 
265 		if (valid_offset (fd, mid))
266 			low = mid;
267 		else
268 			high = mid;
269 	}
270 	valid_offset(fd, 0);
271 	size64 = low + 1;
272 	*retblocks = size64 / blocksize;
273 out:
274 	close(fd);
275 	return rc;
276 }
277 
278 #endif /* WIN32 */
279 
ext2fs_get_device_size(const char * file,int blocksize,blk_t * retblocks)280 errcode_t ext2fs_get_device_size(const char *file, int blocksize,
281 				 blk_t *retblocks)
282 {
283 	errcode_t retval;
284 	blk64_t	blocks;
285 
286 	retval = ext2fs_get_device_size2(file, blocksize, &blocks);
287 	if (retval)
288 		return retval;
289 	if (blocks >= (1ULL << 32))
290 		return EFBIG;
291 	*retblocks = (blk_t) blocks;
292 	return 0;
293 }
294 
295 #ifdef DEBUG
main(int argc,char ** argv)296 int main(int argc, char **argv)
297 {
298 	blk_t	blocks;
299 	int	retval;
300 
301 	if (argc < 2) {
302 		fprintf(stderr, "Usage: %s device\n", argv[0]);
303 		exit(1);
304 	}
305 
306 	retval = ext2fs_get_device_size(argv[1], 1024, &blocks);
307 	if (retval) {
308 		com_err(argv[0], retval,
309 			"while calling ext2fs_get_device_size");
310 		exit(1);
311 	}
312 	printf("Device %s has %u 1k blocks.\n", argv[1], blocks);
313 	exit(0);
314 }
315 #endif
316