aboutsummaryrefslogtreecommitdiff
path: root/sbin/ddb/ddb_script.c
blob: e36cb660638088d3d3d989384bea120df51b7ce4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2007 Robert N. M. Watson
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/types.h>
#include <sys/sysctl.h>

#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>

#include "ddb.h"

/*
 * These commands manage DDB(4) scripts from user space.  For better or worse,
 * the setting and unsetting of scripts is only poorly represented using
 * sysctl(8), and this interface provides a more user-friendly way to
 * accomplish this management, wrapped around lower-level sysctls.  For
 * completeness, listing of scripts is also included.
 */

#define	SYSCTL_SCRIPT	"debug.ddb.scripting.script"
#define	SYSCTL_SCRIPTS	"debug.ddb.scripting.scripts"
#define	SYSCTL_UNSCRIPT	"debug.ddb.scripting.unscript"

/*
 * Print all scripts (scriptname==NULL) or a specific script.
 */
static void
ddb_list_scripts(const char *scriptname)
{
	char *buffer, *line, *nextline;
	char *line_script, *line_scriptname;
	size_t buflen, len;
	int ret;

repeat:
	if (sysctlbyname(SYSCTL_SCRIPTS, NULL, &buflen, NULL, 0) < 0)
		err(EX_OSERR, "sysctl: %s", SYSCTL_SCRIPTS);
	if (buflen == 0)
		return;
	buffer = malloc(buflen);
	if (buffer == NULL)
		err(EX_OSERR, "malloc");
	bzero(buffer, buflen);
	len = buflen;
	ret = sysctlbyname(SYSCTL_SCRIPTS, buffer, &len, NULL, 0);
	if (ret < 0 && errno != ENOMEM)
		err(EX_OSERR, "sysctl: %s", SYSCTL_SCRIPTS);
	if (ret < 0) {
		free(buffer);
		goto repeat;
	}

	/*
	 * We nul'd the buffer before calling sysctl(), so at worst empty.
	 *
	 * If a specific script hasn't been requested, print it all.
	 */
	if (scriptname == NULL) {
		printf("%s", buffer);
		free(buffer);
		return;
	}

	/*
	 * If a specific script has been requested, we have to parse the
	 * string to find it.
	 */
	nextline = buffer;
	while ((line = strsep(&nextline, "\n")) != NULL) {
		line_script = line;
		line_scriptname = strsep(&line_script, "=");
		if (line_script == NULL)
			continue;
		if (strcmp(scriptname, line_scriptname) != 0)
			continue;
		printf("%s\n", line_script);
		break;
	}
	if (line == NULL) {
		errno = ENOENT;
		err(EX_DATAERR, "%s", scriptname);
	}
	free(buffer);
}

/*
 * "ddb script" can be used to either print or set a script.
 */
void
ddb_script(int argc, char *argv[])
{

	if (argc != 2)
		usage();
	argv++;
	argc--;
	if (strchr(argv[0], '=') != 0) {
		if (sysctlbyname(SYSCTL_SCRIPT, NULL, NULL, argv[0],
		    strlen(argv[0]) + 1) < 0)
			err(EX_OSERR, "sysctl: %s", SYSCTL_SCRIPTS);
	} else
		ddb_list_scripts(argv[0]);
}

void
ddb_scripts(int argc, char *argv[] __unused)
{

	if (argc != 1)
		usage();
	ddb_list_scripts(NULL);
}

void
ddb_unscript(int argc, char *argv[])
{
	int ret;

	if (argc != 2)
		usage();
	argv++;
	argc--;
	ret = sysctlbyname(SYSCTL_UNSCRIPT, NULL, NULL, argv[0],
	    strlen(argv[0]) + 1);
	if (ret < 0 && errno == EINVAL) {
		errno = ENOENT;
		err(EX_DATAERR, "sysctl: %s", argv[0]);
	} else if (ret < 0)
		err(EX_OSERR, "sysctl: %s", SYSCTL_UNSCRIPT);
}