xref: /illumos-gate/usr/src/lib/libdevinfo/devinfo_dli.c (revision 7a6d80f1660abd4755c68cbd094d4a914681d26e)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Interfaces for getting device configuration data from kernel
29  * through the devinfo driver.
30  */
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <strings.h>
36 #include <fcntl.h>
37 #include <unistd.h>
38 #include <sys/stat.h>
39 #include <sys/types.h>
40 #include <stdarg.h>
41 #include <unistd.h>
42 #include <libgen.h>
43 #include "libdevinfo.h"
44 
45 /* Function Prototypes */
46 static int di_dli_open(char *, int, short, int);
47 
48 #define	DLI_NAME	0x1
49 
50 /*
51  * Private hotplug interfaces to be used between cfgadm pci plugin and
52  * devfsadm link generator.
53  */
54 
55 
56 /*
57  * returns a devlink info file name derived from <path>
58  * callers need to free the returned string
59  */
60 char *
61 di_dli_name(char *path)
62 {
63 #define	dliroot		"/etc/devices/dli/info."
64 #define	dliroot_len	(sizeof (dliroot) - 1)
65 
66 	char *dlipath;
67 	int dlipathsz;
68 	char *basep;
69 
70 	basep = basename(path);
71 	dlipathsz = strlen(basep) + dliroot_len + 1;
72 	dlipath = malloc(sizeof (char) * dlipathsz);
73 
74 	(void) snprintf(dlipath, dlipathsz, "%s%s", dliroot, basep);
75 	dlipath[dlipathsz - 1] = '\0';
76 	return (dlipath);
77 
78 #undef	dlipre
79 #undef	dlipre_len
80 #undef	dliroot
81 #undef	dliroot_len
82 }
83 
84 
85 static int
86 di_dli_open(char *path, int oflag, short l_type, int flags)
87 {
88 	int fd;
89 	char *dlipath, *dlipath_dir, *dlipath_dup;
90 	struct stat statbuf;
91 	int mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
92 	flock_t lock;
93 
94 	dlipath = (flags & DLI_NAME) ? di_dli_name(path) : (char *)path;
95 	dlipath_dup = strdup(dlipath);
96 	dlipath_dir = dirname(dlipath_dup);
97 
98 	if (stat(dlipath_dir, &statbuf) < 0) {
99 		if (mkdirp(dlipath_dir,
100 		    S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0) {
101 			fd = -1;
102 			goto OUT;
103 		}
104 	}
105 
106 	fd = open(dlipath, oflag, mode);
107 	if (fd < 0)
108 		goto OUT;
109 
110 	if (fchmod(fd, mode) < 0) {
111 		(void) close(fd);
112 		fd = -1;
113 		goto OUT;
114 	}
115 
116 	bzero(&lock, sizeof (lock));
117 	lock.l_type = l_type;
118 	if (fcntl(fd, F_SETLKW, &lock) < 0) {
119 		(void) close(fd);
120 		fd = -1;
121 	}
122 OUT:
123 	free(dlipath_dup);
124 	if (flags & DLI_NAME)
125 		free(dlipath);
126 	return (fd);
127 }
128 
129 
130 int
131 di_dli_openr(char *path)
132 {
133 	return (di_dli_open(path, O_RDONLY, F_RDLCK, DLI_NAME));
134 }
135 
136 
137 int
138 di_dli_openw(char *path)
139 {
140 	return (di_dli_open(path, O_RDWR | O_SYNC | O_TRUNC | O_CREAT,
141 	    F_WRLCK, DLI_NAME));
142 }
143 
144 
145 void
146 di_dli_close(int fd)
147 {
148 	flock_t lock;
149 	if (fd < 0)
150 		return;
151 
152 	bzero(&lock, sizeof (lock));
153 	lock.l_type = F_UNLCK;
154 	(void) fcntl(fd, F_SETLK, &lock);
155 	(void) close(fd);
156 }
157