xref: /freebsd/lib/libgeom/geom_ctl.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2003 Poul-Henning Kamp
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The names of the authors may not be used to endorse or promote
16  *    products derived from this software without specific prior written
17  *    permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #include <sys/types.h>
35 #include <sys/queue.h>
36 #include <fcntl.h>
37 #include <errno.h>
38 #include <paths.h>
39 #include <stdarg.h>
40 #include <stdint.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #define GCTL_TABLE 1
47 #include <libgeom.h>
48 
49 /*
50  * Global pointer to a string that is used to avoid an errorneous free in
51  * gctl_free.
52  */
53 static char nomemmsg[] = "Could not allocate memory";
54 
55 void
56 gctl_dump(struct gctl_req *req, FILE *f)
57 {
58 	unsigned int i;
59 	int j;
60 	struct gctl_req_arg *ap;
61 
62 	if (req == NULL) {
63 		fprintf(f, "Dump of gctl request at NULL\n");
64 		return;
65 	}
66 	fprintf(f, "Dump of gctl request at %p:\n", req);
67 	if (req->error != NULL)
68 		fprintf(f, "  error:\t\"%s\"\n", req->error);
69 	else
70 		fprintf(f, "  error:\tNULL\n");
71 	for (i = 0; i < req->narg; i++) {
72 		ap = &req->arg[i];
73 		fprintf(f, "  param:\t\"%s\" (%d)", ap->name, ap->nlen);
74 		fprintf(f, " [%s%s",
75 		    ap->flag & GCTL_PARAM_RD ? "R" : "",
76 		    ap->flag & GCTL_PARAM_WR ? "W" : "");
77 		fflush(f);
78 		if (ap->flag & GCTL_PARAM_ASCII)
79 			fprintf(f, "%d] = \"%s\"", ap->len, (char *)ap->value);
80 		else if (ap->len > 0) {
81 			fprintf(f, "%d] = ", ap->len);
82 			fflush(f);
83 			for (j = 0; j < ap->len; j++) {
84 				fprintf(f, " %02x", ((u_char *)ap->value)[j]);
85 			}
86 		} else {
87 			fprintf(f, "0] = %p", ap->value);
88 		}
89 		fprintf(f, "\n");
90 	}
91 }
92 
93 /*
94  * Set an error message, if one does not already exist.
95  */
96 static void
97 gctl_set_error(struct gctl_req *req, const char *error, ...)
98 {
99 	va_list ap;
100 
101 	if (req->error != NULL)
102 		return;
103 	va_start(ap, error);
104 	vasprintf(&req->error, error, ap);
105 	va_end(ap);
106 }
107 
108 /*
109  * Check that a malloc operation succeeded, and set a consistent error
110  * message if not.
111  */
112 static void
113 gctl_check_alloc(struct gctl_req *req, void *ptr)
114 {
115 
116 	if (ptr != NULL)
117 		return;
118 	gctl_set_error(req, nomemmsg);
119 	if (req->error == NULL)
120 		req->error = nomemmsg;
121 }
122 
123 /*
124  * Allocate a new request handle of the specified type.
125  * XXX: Why bother checking the type ?
126  */
127 struct gctl_req *
128 gctl_get_handle(void)
129 {
130 
131 	return (calloc(1, sizeof(struct gctl_req)));
132 }
133 
134 /*
135  * Allocate space for another argument.
136  */
137 static struct gctl_req_arg *
138 gctl_new_arg(struct gctl_req *req)
139 {
140 	struct gctl_req_arg *ap;
141 
142 	req->narg++;
143 	req->arg = reallocf(req->arg, sizeof *ap * req->narg);
144 	gctl_check_alloc(req, req->arg);
145 	if (req->arg == NULL) {
146 		req->narg = 0;
147 		return (NULL);
148 	}
149 	ap = req->arg + (req->narg - 1);
150 	memset(ap, 0, sizeof *ap);
151 	return (ap);
152 }
153 
154 static void
155 gctl_param_add(struct gctl_req *req, const char *name, int len, void *value,
156     int flag)
157 {
158 	struct gctl_req_arg *ap;
159 
160 	if (req == NULL || req->error != NULL)
161 		return;
162 	ap = gctl_new_arg(req);
163 	if (ap == NULL)
164 		return;
165 	ap->name = strdup(name);
166 	gctl_check_alloc(req, ap->name);
167 	if (ap->name == NULL)
168 		return;
169 	ap->nlen = strlen(ap->name) + 1;
170 	ap->value = value;
171 	ap->flag = flag;
172 	if (len >= 0)
173 		ap->len = len;
174 	else if (len < 0) {
175 		ap->flag |= GCTL_PARAM_ASCII;
176 		ap->len = strlen(value) + 1;
177 	}
178 }
179 
180 void
181 gctl_ro_param(struct gctl_req *req, const char *name, int len, const void* value)
182 {
183 
184 	gctl_param_add(req, name, len, __DECONST(void *, value), GCTL_PARAM_RD);
185 }
186 
187 void
188 gctl_rw_param(struct gctl_req *req, const char *name, int len, void *value)
189 {
190 
191 	gctl_param_add(req, name, len, value, GCTL_PARAM_RW);
192 }
193 
194 const char *
195 gctl_issue(struct gctl_req *req)
196 {
197 	int fd, error;
198 
199 	if (req == NULL)
200 		return ("NULL request pointer");
201 	if (req->error != NULL)
202 		return (req->error);
203 
204 	req->version = GCTL_VERSION;
205 	req->lerror = BUFSIZ;		/* XXX: arbitrary number */
206 	req->error = calloc(1, req->lerror);
207 	if (req->error == NULL) {
208 		gctl_check_alloc(req, req->error);
209 		return (req->error);
210 	}
211 	req->lerror--;
212 	fd = open(_PATH_DEV PATH_GEOM_CTL, O_RDONLY);
213 	if (fd < 0)
214 		return(strerror(errno));
215 	error = ioctl(fd, GEOM_CTL, req);
216 	close(fd);
217 	if (req->error[0] != '\0')
218 		return (req->error);
219 	if (error != 0)
220 		return(strerror(errno));
221 	return (NULL);
222 }
223 
224 void
225 gctl_free(struct gctl_req *req)
226 {
227 	unsigned int i;
228 
229 	if (req == NULL)
230 		return;
231 	for (i = 0; i < req->narg; i++) {
232 		if (req->arg[i].name != NULL)
233 			free(req->arg[i].name);
234 	}
235 	free(req->arg);
236 	if (req->error != NULL && req->error != nomemmsg)
237 		free(req->error);
238 	free(req);
239 }
240