xref: /illumos-gate/usr/src/lib/libvolmgt/volmgt.h (revision 7c478bd9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1993, by Sun Microsystems, Inc.
24  */
25 
26 #ifndef	_VOLMGT_H
27 #define	_VOLMGT_H
28 
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 #include <sys/types.h>
36 
37 /*
38  * volmgt_check:
39  *	have volume management look at its devices to check
40  *	for media having arrived.  Since volume management can't
41  *	automatically check all types of devices, this function is provided
42  *	to allow applications to cause the check to happen automatically.
43  *
44  * arguments:
45  *	path - the name of the device in /dev.  For example,
46  *	  /dev/rdiskette.  If path is NULL, all "checkable" devices are
47  *	  checked.
48  *
49  * return value(s):
50  *	TRUE if media was found in the device, FALSE if not.
51  */
52 int volmgt_check(char *path);
53 
54 /*
55  * volmgt_inuse:
56  *	check to see if volume management is currently
57  *	managing a particular device.
58  *
59  * arguments:
60  *	path - the name of the device in /dev.  For example,
61  *	  "/dev/rdiskette".
62  *
63  * return value(s):
64  *	TRUE if volume management is managing the device, FALSE if not.
65  */
66 int volmgt_inuse(char *path);
67 
68 /*
69  * volmgt_running:
70  *	check to see if volume management is running.
71  *
72  * arguments:
73  *	none.
74  *
75  * return value(s):
76  *	TRUE if volume management is running, FALSE if not.
77  */
78 int volmgt_running(void);
79 
80 /*
81  * volmgt_symname:
82  *	Returns the volume management symbolic name
83  *	for a given device.  If an application wants to determine
84  *	what the symbolic name (e.g. "floppy0") for the /dev/rdiskette
85  *	device would be, this is the function to use.
86  *
87  * arguments:
88  *	path - a string containing the /dev device name.  For example,
89  *	"/dev/diskette" or "/dev/rdiskette".
90  *
91  * return value(s):
92  *	pointer to a string containing the symbolic name.
93  *
94  *	NULL indicates that volume management isn't managing that device.
95  *
96  *	The string must be free(3)'d.
97  */
98 char 	*volmgt_symname(char *path);
99 
100 /*
101  * volmgt_symdev:
102  *	Returns the device given the volume management
103  *	symbolic name. If an application wants to determine
104  *	what the device associated with a particular symbolic name
105  *	might be, this is the function to use.
106  *
107  * arguments:
108  *	path - a string containing the symbolic device name.  For example,
109  *	"cdrom0" or "floppy0".
110  *
111  * return value(s):
112  *	pointer to a string containing the /dev name.
113  *
114  *	NULL indicates that volume management isn't managing that device.
115  *
116  *	The string must be free(3)'d.
117  */
118 char 	*volmgt_symdev(char *symname);
119 
120 /*
121  * volmgt_ownspath:
122  *	check to see if the given path is contained in
123  *	the volume management name space.
124  *
125  * arguments:
126  *	path - string containing the path.
127  *
128  * return value(s):
129  *	TRUE if the path is owned by volume management, FALSE if not.
130  *	Will return FALSE if volume management isn't running.
131  *
132  */
133 int	volmgt_ownspath(char *path);
134 
135 /*
136  * volmgt_root:
137  *	return the root of where the volume management
138  *	name space is mounted.
139  *
140  * arguments:
141  *	none.
142  *
143  * return value(s):
144  *	Returns a pointer to a string containing the path to the
145  *	volume management root (e.g. "/vol").
146  *	Will return NULL if volume management isn't running.
147  */
148 const char 	*volmgt_root(void);
149 
150 /*
151  * media_findname:
152  *	try to come up with the character device when
153  *	provided with a starting point.  This interface provides the
154  *	application programmer to provide "user friendly" names and
155  *	easily determine the "/vol" name.
156  *
157  * arguments:
158  *	start - a string describing a device.  This string can be:
159  *		- a full path name to a device (insures it's a
160  *		  character device by using getfullrawname()).
161  *		- a full path name to a volume management media name
162  *		  with partitions (will return the lowest numbered
163  *		  raw partition.
164  *		- the name of a piece of media (e.g. "fred").
165  *		- a symbolic device name (e.g. floppy0, cdrom0, etc)
166  *		- a name like "floppy" or "cdrom".  Will pick the lowest
167  *		  numbered device with media in it.
168  *
169  * return value(s):
170  *	A pointer to a string that contains the character device
171  *	most appropriate to the "start" argument.
172  *
173  *	NULL indicates that we were unable to find media based on "start".
174  *
175  *	The string must be free(3)'d.
176  */
177 char 	*media_findname(char *start);
178 
179 /*
180  * media_getattr:
181  *	returns the value for an attribute for a piece of
182  * 	removable media.
183  *
184  * arguments:
185  *	path - Path to the media in /vol.  Can be the block or character
186  *		device.
187  *
188  *	attr - name of the attribute.
189  *
190  * return value(s):
191  *	returns NULL or a pointer to a string that contains the value for
192  * 	the requested attribute.
193  *
194  *	NULL can mean:
195  *	 - the media doesn't exist
196  *	 - there is no more space for malloc(3)
197  *	 - the attribute doesn't exist for the named media
198  *	 - the attribute is a boolean and is FALSE
199  *
200  *	the pointer to the string must be free'd with free(3).
201  */
202 char *media_getattr(char *path, char *attr);
203 
204 /*
205  * media_setattr:
206  *	set an attribute for a piece of media to a
207  *	particular value.
208  *
209  * arguments:
210  *	path - Path to the media in /vol.  Can be the block or character
211  *		device.
212  *
213  *	attr - name of the attribute.
214  *
215  *	value - value of the attribute.  If value == "", the flag is
216  *	    considered to be a boolean that is TRUE.  If value == 0, it
217  *	    is considered to be a FALSE boolean.
218  *
219  * return value(s):
220  *	TRUE on success, FALSE for failure.
221  *
222  *	Can fail because:
223  *		- don't have permission to set the attribute because caller
224  *		  is not the owner of the media and attribute is a "system"
225  *		  attribute.
226  *
227  *		- don't have permission to set the attribute because the
228  *		  attribute is a "system" attribute and is read-only.
229  */
230 int	media_setattr(char *path, char *attr, char *value);
231 
232 /*
233  * media_getid:
234  *	return the "id" of a piece of media.
235  *
236  * arguments:
237  *	path - Path to the media in /vol.  Can be the block or character
238  *		device.
239  * return value(s):
240  *	returns a u_longlong_t that is the "id" of the volume.
241  *
242  */
243 u_longlong_t	media_getid(char *path);
244 
245 /*
246  * volmgt_feature_enabled:
247  *	check to see if a volume management feature is available
248  *
249  * arguments:
250  *	feat_str - a string containing the feature to be checked for
251  *
252  * return value(s):
253  *	returns non-zero if the specified feature is available
254  *	in volume management, else return zero
255  */
256 int	volmgt_feature_enabled(char *feat_str);
257 
258 /*
259  * volmgt_acquire
260  *	try to acquire the volmgt advisory device reservation
261  *	for a specific device. -- if volmgt isn't running then try to
262  *	reserve the device specified
263  *
264  * arguments:
265  *	dev - a device name to attempt reserving.  This string can be:
266  *		- a full path name to a device in /vol if volmgt is running
267  *		- a symbolic device name (e.g. floppy0) if volmgt is running
268  *		- a /dev pathname if volmgt is not running
269  *
270  *	id  - a reservation string that hopefully describes the application
271  *		making this reservation.
272  *
273  *	ovr - an override indicator.  If set to non-zero, the caller requests
274  *		that this reservation be made unconditionally.
275  *
276  *	err - the address of a char ptr that will updated to point to the
277  *		id argument used when the current device was reserved.  This
278  *		is only used when the current reservation attempt fails due
279  *		to an already existing reservation for this device.
280  *
281  *	pidp - a pointer to a pid_t type.  If this argument is not NULL
282  *		and the requested device is already reserved, the process
283  *		id of the reservation owner will be returned in this
284  *		location.
285  *
286  *
287  * return value(s):
288  *	A non-zero indicator if successful.
289  *
290  *	A zero indicator if unsuccessful.  If errno is EBUSY, then the err
291  *	argument will be set to point to the string that the process currently
292  *	holding the reservation supplied when reserving the device.  It is up
293  *	to the caller to release the storage occupied by the string via
294  *	free(3C) when no longer needed.
295  */
296 int	volmgt_acquire(char *dev, char *id, int ovr, char **err, pid_t *pidp);
297 
298 /*
299  * the max length for the "id" string in volmgt_acquire
300  */
301 #define	VOL_RSV_MAXIDLEN	256
302 
303 /*
304  * volmgt_release:
305  *	try to release the volmgt advisory device reservation
306  *	for a specific device.
307  *
308  * arguments:
309  *	dev - a device name to attempt reserving.  This string can be:
310  *		- a full path name to a device in /vol if volmgt is running
311  *		- a symbolic device name (e.g. floppy0) if volmgt is running
312  *		- a /dev pathname if volmgt is not running
313  *
314  * return value(s):
315  *	A non-zero indicator if successful
316  *	A zero indicator if unsuccessful
317  *
318  * preconditions:
319  *	none
320  */
321 int	volmgt_release(char *dev);
322 
323 #ifdef	__cplusplus
324 }
325 #endif
326 
327 #endif	/* _VOLMGT_H */
328