xref: /freebsd/lib/libgeom/geom_ctl.c (revision ef36b3f75658d201edb495068db5e1be49593de5)
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 <sys/types.h>
33 #include <sys/queue.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include <paths.h>
37 #include <stdarg.h>
38 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 #define GCTL_TABLE 1
45 #include <libgeom.h>
46 
47 /*
48  * Global pointer to a string that is used to avoid an errorneous free in
49  * gctl_free.
50  */
51 static char nomemmsg[] = "Could not allocate memory";
52 
53 void
54 gctl_dump(struct gctl_req *req, FILE *f)
55 {
56 	unsigned int i;
57 	int j;
58 	struct gctl_req_arg *ap;
59 
60 	if (req == NULL) {
61 		fprintf(f, "Dump of gctl request at NULL\n");
62 		return;
63 	}
64 	fprintf(f, "Dump of gctl request at %p:\n", req);
65 	if (req->error != NULL)
66 		fprintf(f, "  error:\t\"%s\"\n", req->error);
67 	else
68 		fprintf(f, "  error:\tNULL\n");
69 	for (i = 0; i < req->narg; i++) {
70 		ap = &req->arg[i];
71 		fprintf(f, "  param:\t\"%s\" (%d)", ap->name, ap->nlen);
72 		fprintf(f, " [%s%s",
73 		    ap->flag & GCTL_PARAM_RD ? "R" : "",
74 		    ap->flag & GCTL_PARAM_WR ? "W" : "");
75 		fflush(f);
76 		if (ap->flag & GCTL_PARAM_ASCII)
77 			fprintf(f, "%d] = \"%s\"", ap->len, (char *)ap->value);
78 		else if (ap->len > 0) {
79 			fprintf(f, "%d] = ", ap->len);
80 			fflush(f);
81 			for (j = 0; j < ap->len; j++) {
82 				fprintf(f, " %02x", ((u_char *)ap->value)[j]);
83 			}
84 		} else {
85 			fprintf(f, "0] = %p", ap->value);
86 		}
87 		fprintf(f, "\n");
88 	}
89 }
90 
91 /*
92  * Set an error message, if one does not already exist.
93  */
94 static void
95 gctl_set_error(struct gctl_req *req, const char *error, ...)
96 {
97 	va_list ap;
98 
99 	if (req->error != NULL)
100 		return;
101 	va_start(ap, error);
102 	vasprintf(&req->error, error, ap);
103 	va_end(ap);
104 }
105 
106 /*
107  * Check that a malloc operation succeeded, and set a consistent error
108  * message if not.
109  */
110 static void
111 gctl_check_alloc(struct gctl_req *req, void *ptr)
112 {
113 
114 	if (ptr != NULL)
115 		return;
116 	gctl_set_error(req, nomemmsg);
117 	if (req->error == NULL)
118 		req->error = nomemmsg;
119 }
120 
121 /*
122  * Allocate a new request handle of the specified type.
123  * XXX: Why bother checking the type ?
124  */
125 struct gctl_req *
126 gctl_get_handle(void)
127 {
128 
129 	return (calloc(1, sizeof(struct gctl_req)));
130 }
131 
132 /*
133  * Allocate space for another argument.
134  */
135 static struct gctl_req_arg *
136 gctl_new_arg(struct gctl_req *req)
137 {
138 	struct gctl_req_arg *ap;
139 
140 	req->narg++;
141 	req->arg = reallocf(req->arg, sizeof *ap * req->narg);
142 	gctl_check_alloc(req, req->arg);
143 	if (req->arg == NULL) {
144 		req->narg = 0;
145 		return (NULL);
146 	}
147 	ap = req->arg + (req->narg - 1);
148 	memset(ap, 0, sizeof *ap);
149 	return (ap);
150 }
151 
152 static void
153 gctl_param_add(struct gctl_req *req, const char *name, int len, void *value,
154     int flag)
155 {
156 	struct gctl_req_arg *ap;
157 
158 	if (req == NULL || req->error != NULL)
159 		return;
160 	ap = gctl_new_arg(req);
161 	if (ap == NULL)
162 		return;
163 	ap->name = strdup(name);
164 	gctl_check_alloc(req, ap->name);
165 	if (ap->name == NULL)
166 		return;
167 	ap->nlen = strlen(ap->name) + 1;
168 	ap->value = value;
169 	ap->flag = flag;
170 	if (len >= 0)
171 		ap->len = len;
172 	else if (len < 0) {
173 		ap->flag |= GCTL_PARAM_ASCII;
174 		ap->len = strlen(value) + 1;
175 	}
176 }
177 
178 void
179 gctl_ro_param(struct gctl_req *req, const char *name, int len, const void* value)
180 {
181 
182 	gctl_param_add(req, name, len, __DECONST(void *, value), GCTL_PARAM_RD);
183 }
184 
185 void
186 gctl_rw_param(struct gctl_req *req, const char *name, int len, void *value)
187 {
188 
189 	gctl_param_add(req, name, len, value, GCTL_PARAM_RW);
190 }
191 
192 const char *
193 gctl_issue(struct gctl_req *req)
194 {
195 	int fd, error;
196 
197 	if (req == NULL)
198 		return ("NULL request pointer");
199 	if (req->error != NULL)
200 		return (req->error);
201 
202 	req->version = GCTL_VERSION;
203 	req->lerror = BUFSIZ;		/* XXX: arbitrary number */
204 	req->error = calloc(1, req->lerror);
205 	if (req->error == NULL) {
206 		gctl_check_alloc(req, req->error);
207 		return (req->error);
208 	}
209 	req->lerror--;
210 	fd = open(_PATH_DEV PATH_GEOM_CTL, O_RDONLY);
211 	if (fd < 0)
212 		return(strerror(errno));
213 	error = ioctl(fd, GEOM_CTL, req);
214 	close(fd);
215 	if (req->error[0] != '\0')
216 		return (req->error);
217 	if (error != 0)
218 		return(strerror(errno));
219 	return (NULL);
220 }
221 
222 void
223 gctl_free(struct gctl_req *req)
224 {
225 	unsigned int i;
226 
227 	if (req == NULL)
228 		return;
229 	for (i = 0; i < req->narg; i++) {
230 		if (req->arg[i].name != NULL)
231 			free(req->arg[i].name);
232 	}
233 	free(req->arg);
234 	if (req->error != NULL && req->error != nomemmsg)
235 		free(req->error);
236 	free(req);
237 }
238