xref: /titanic_41/usr/src/cmd/avs/dsstat/common.c (revision 42d159821800ff240cc201c8fe07f575b9e8a62b)
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  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <strings.h>
30 #include <errno.h>
31 #include <kstat.h>
32 #include <signal.h>
33 #include <setjmp.h>
34 
35 #include "sdbc_stats.h"
36 #include "report.h"
37 #include "common.h"
38 
39 static sigjmp_buf env;
40 static sig_atomic_t sig_raised = 0;
41 static void sig_handler(int);
42 
43 void
44 sig_handler(int sig)
45 {
46 	switch (sig) {
47 		case SIGSEGV:
48 			sig_raised = 1;
49 			siglongjmp(env, sig);
50 		default:
51 			exit(sig);
52 	}
53 }
54 
55 /*
56  * kstat_retrieve() - populate the ks_data field of the kstat_t structure
57  *
58  * This function is a user-land equivalent of a ks_snapshot
59  *
60  * parameters
61  * 	kstat_ctl_t *kc - kstat_ctl_t structure representing returned from
62  *			  kstat_open()
63  * 	kstat_t *ksp - kstat_t strcture to popluate ks_data into
64  *
65  * returns
66  * 	NULL pointer on failure
67  * 	kstat_t * structure on success
68  */
69 kstat_t *
70 kstat_retrieve(kstat_ctl_t *kc, kstat_t *ksp)
71 {
72 
73 	kstat_t *rval;
74 	kstat_named_t *knp;
75 	char *end;
76 	int i;
77 	struct sigaction segv_act;	/* default actions */
78 
79 	if (ksp == NULL)
80 		return (NULL);
81 
82 	if (ksp->ks_data == NULL &&
83 	    kstat_read(kc, ksp, NULL) == -1)
84 		return (NULL);
85 
86 	rval = (kstat_t *)calloc(1, sizeof (*ksp));
87 	(void) memcpy(rval, ksp, sizeof (*ksp));
88 
89 	rval->ks_data = (void *) calloc(1, ksp->ks_data_size);
90 	(void) memcpy(rval->ks_data, ksp->ks_data,
91 	    sizeof (kstat_named_t) * ksp->ks_ndata);
92 
93 	/* special handling for variable length string KSTAT_DATA_STRING */
94 	knp = (kstat_named_t *)rval->ks_data;
95 	end = (char *)(knp + ksp->ks_ndata);
96 	for (i = 0; i < ksp->ks_ndata; i++, knp++) {
97 		if (knp->data_type == KSTAT_DATA_STRING &&
98 		    KSTAT_NAMED_STR_PTR(knp) != NULL) {
99 			/* catch SIGSEGV (bug 6384130) */
100 			sig_raised = 0;
101 			(void) sigaction(SIGSEGV, NULL, &segv_act);
102 			(void) signal(SIGSEGV, sig_handler);
103 
104 			(void) strncpy(end, KSTAT_NAMED_STR_PTR(knp),
105 			    KSTAT_NAMED_STR_BUFLEN(knp));
106 			KSTAT_NAMED_STR_PTR(knp) = end;
107 			end += KSTAT_NAMED_STR_BUFLEN(knp);
108 
109 			/* bug 6384130 */
110 			(void) sigsetjmp(env, 0);
111 			if (sig_raised) {
112 				bzero(end, KSTAT_NAMED_STR_BUFLEN(knp));
113 				KSTAT_NAMED_STR_PTR(knp) = end;
114 				end += KSTAT_NAMED_STR_BUFLEN(knp);
115 			}
116 			(void) sigaction(SIGSEGV, &segv_act, NULL);
117 		}
118 	}
119 
120 	return (rval);
121 }
122 
123 /*
124  * kstat_value() - retrieve value of a field in a kstat_named_t kstat.
125  *
126  * parameters
127  * 	kstat_t *ksp - kstat containing the field
128  * 	char *name - text string representing the field name
129  *
130  * returns
131  *	void * - pointer to data retrieved
132  */
133 void *
134 kstat_value(kstat_t *ksp, char *name)
135 {
136 	kstat_named_t *knm;
137 
138 	if ((knm = kstat_data_lookup(ksp, name)) == NULL)
139 		return (NULL);
140 
141 	switch (knm->data_type) {
142 		case KSTAT_DATA_CHAR :
143 			return (knm->value.c);
144 		case KSTAT_DATA_INT32 :
145 			return (&knm->value.i32);
146 		case KSTAT_DATA_UINT32 :
147 			return (&knm->value.ui32);
148 		case KSTAT_DATA_INT64 :
149 			return (&knm->value.i64);
150 		case KSTAT_DATA_UINT64 :
151 			return (&knm->value.ui64);
152 		case KSTAT_DATA_STRING :
153 			return (KSTAT_NAMED_STR_PTR(knm));
154 	}
155 
156 	return (NULL);
157 }
158 
159 /*
160  * kstat_free() - deallocated memory associated with a kstat
161  *
162  * paramters
163  * 	kstat_t ksp - kstat to be deallocated
164  *
165  * returns
166  * 	void
167  */
168 void
169 kstat_free(kstat_t *ksp)
170 {
171 	if (ksp != NULL) {
172 		if (ksp->ks_data != NULL)
173 			free(ksp->ks_data);
174 		free(ksp);
175 	}
176 }
177 
178 uint32_t
179 kstat_delta(kstat_t *pksp, kstat_t *cksp, char *name)
180 {
181 	uint32_t *pv, *cv;
182 
183 	pv = kstat_value(pksp, name);
184 	cv = kstat_value(cksp, name);
185 
186 	return (u32_delta(*pv, *cv));
187 }
188