xref: /freebsd/lib/libgeom/geom_ctl.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 2003 Poul-Henning Kamp
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The names of the authors may not be used to endorse or promote
14  *    products derived from this software without specific prior written
15  *    permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #include <stdio.h>
33 #include <fcntl.h>
34 #include <errno.h>
35 #include <stdint.h>
36 #include <sys/types.h>
37 #include <stdarg.h>
38 #include <unistd.h>
39 #include <string.h>
40 #include <stdlib.h>
41 #include <paths.h>
42 
43 #include <sys/queue.h>
44 
45 #define GCTL_TABLE 1
46 #include <libgeom.h>
47 
48 /*
49  * Global pointer to a string that is used to avoid an errorneous free in
50  * gctl_free.
51  */
52 static char nomemmsg[] = "Could not allocate memory";
53 
54 void
55 gctl_dump(struct gctl_req *req, FILE *f)
56 {
57 	unsigned int i;
58 	int j;
59 	struct gctl_req_arg *ap;
60 
61 	if (req == NULL) {
62 		fprintf(f, "Dump of gctl request at NULL\n");
63 		return;
64 	}
65 	fprintf(f, "Dump of gctl request at %p:\n", req);
66 	if (req->error != NULL)
67 		fprintf(f, "  error:\t\"%s\"\n", req->error);
68 	else
69 		fprintf(f, "  error:\tNULL\n");
70 	for (i = 0; i < req->narg; i++) {
71 		ap = &req->arg[i];
72 		fprintf(f, "  param:\t\"%s\" (%d)", ap->name, ap->nlen);
73 		fprintf(f, " [%s%s",
74 		    ap->flag & GCTL_PARAM_RD ? "R" : "",
75 		    ap->flag & GCTL_PARAM_WR ? "W" : "");
76 		fflush(f);
77 		if (ap->flag & GCTL_PARAM_ASCII)
78 			fprintf(f, "%d] = \"%s\"", ap->len, (char *)ap->value);
79 		else if (ap->len > 0) {
80 			fprintf(f, "%d] = ", ap->len);
81 			fflush(f);
82 			for (j = 0; j < ap->len; j++) {
83 				fprintf(f, " %02x", ((u_char *)ap->value)[j]);
84 			}
85 		} else {
86 			fprintf(f, "0] = %p", ap->value);
87 		}
88 		fprintf(f, "\n");
89 	}
90 }
91 
92 /*
93  * Set an error message, if one does not already exist.
94  */
95 static void
96 gctl_set_error(struct gctl_req *req, const char *error, ...)
97 {
98 	va_list ap;
99 
100 	if (req->error != NULL)
101 		return;
102 	va_start(ap, error);
103 	vasprintf(&req->error, error, ap);
104 	va_end(ap);
105 }
106 
107 /*
108  * Check that a malloc operation succeeded, and set a consistent error
109  * message if not.
110  */
111 static void
112 gctl_check_alloc(struct gctl_req *req, void *ptr)
113 {
114 
115 	if (ptr != NULL)
116 		return;
117 	gctl_set_error(req, nomemmsg);
118 	if (req->error == NULL)
119 		req->error = nomemmsg;
120 }
121 
122 /*
123  * Allocate a new request handle of the specified type.
124  * XXX: Why bother checking the type ?
125  */
126 struct gctl_req *
127 gctl_get_handle(void)
128 {
129 
130 	return (calloc(1, sizeof(struct gctl_req)));
131 }
132 
133 /*
134  * Allocate space for another argument.
135  */
136 static struct gctl_req_arg *
137 gctl_new_arg(struct gctl_req *req)
138 {
139 	struct gctl_req_arg *ap;
140 
141 	req->narg++;
142 	req->arg = reallocf(req->arg, sizeof *ap * req->narg);
143 	gctl_check_alloc(req, req->arg);
144 	if (req->arg == NULL) {
145 		req->narg = 0;
146 		return (NULL);
147 	}
148 	ap = req->arg + (req->narg - 1);
149 	memset(ap, 0, sizeof *ap);
150 	return (ap);
151 }
152 
153 static void
154 gctl_param_add(struct gctl_req *req, const char *name, int len, void *value,
155     int flag)
156 {
157 	struct gctl_req_arg *ap;
158 
159 	if (req == NULL || req->error != NULL)
160 		return;
161 	ap = gctl_new_arg(req);
162 	if (ap == NULL)
163 		return;
164 	ap->name = strdup(name);
165 	gctl_check_alloc(req, ap->name);
166 	if (ap->name == NULL)
167 		return;
168 	ap->nlen = strlen(ap->name) + 1;
169 	ap->value = value;
170 	ap->flag = flag;
171 	if (len >= 0)
172 		ap->len = len;
173 	else if (len < 0) {
174 		ap->flag |= GCTL_PARAM_ASCII;
175 		ap->len = strlen(value) + 1;
176 	}
177 }
178 
179 void
180 gctl_ro_param(struct gctl_req *req, const char *name, int len, const void* value)
181 {
182 
183 	gctl_param_add(req, name, len, __DECONST(void *, value), GCTL_PARAM_RD);
184 }
185 
186 void
187 gctl_rw_param(struct gctl_req *req, const char *name, int len, void *value)
188 {
189 
190 	gctl_param_add(req, name, len, value, GCTL_PARAM_RW);
191 }
192 
193 const char *
194 gctl_issue(struct gctl_req *req)
195 {
196 	int fd, error;
197 
198 	if (req == NULL)
199 		return ("NULL request pointer");
200 	if (req->error != NULL)
201 		return (req->error);
202 
203 	req->version = GCTL_VERSION;
204 	req->lerror = BUFSIZ;		/* XXX: arbitrary number */
205 	req->error = calloc(1, req->lerror);
206 	if (req->error == NULL) {
207 		gctl_check_alloc(req, req->error);
208 		return (req->error);
209 	}
210 	req->lerror--;
211 	fd = open(_PATH_DEV PATH_GEOM_CTL, O_RDONLY);
212 	if (fd < 0)
213 		return(strerror(errno));
214 	error = ioctl(fd, GEOM_CTL, req);
215 	close(fd);
216 	if (req->error[0] != '\0')
217 		return (req->error);
218 	if (error != 0)
219 		return(strerror(errno));
220 	return (NULL);
221 }
222 
223 void
224 gctl_free(struct gctl_req *req)
225 {
226 	unsigned int i;
227 
228 	if (req == NULL)
229 		return;
230 	for (i = 0; i < req->narg; i++) {
231 		if (req->arg[i].name != NULL)
232 			free(req->arg[i].name);
233 	}
234 	free(req->arg);
235 	if (req->error != NULL && req->error != nomemmsg)
236 		free(req->error);
237 	free(req);
238 }
239