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
39static sigjmp_buf env;
40static sig_atomic_t sig_raised = 0;
41static void sig_handler(int);
42
43void
44sig_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 */
69kstat_t *
70kstat_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 */
133void *
134kstat_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 */
168void
169kstat_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
178uint32_t
179kstat_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