summaryrefslogtreecommitdiffstats
path: root/dmi.c
blob: 40ca85c77ea17f18f3159765182a34071bb70aa6 (plain)
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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
/*
 * This file is part of the flashrom project.
 *
 * Copyright (C) 2009,2010 Michael Karcher
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#include "flash.h"

int has_dmi_support = 0;

#if STANDALONE

/* Stub to indicate missing DMI functionality.
 * has_dmi_support is 0 by default, so nothing to do here.
 * Because dmidecode is not available on all systems, the goal is to implement
 * the DMI subset we need directly in this file.
 */
void dmi_init(void)
{
}

int dmi_match(const char *pattern)
{
	return 0;
}

#else /* STANDALONE */

const char *dmidecode_names[] = {
	"system-manufacturer",
	"system-product-name",
	"system-version",
	"baseboard-manufacturer",
	"baseboard-product-name",
	"baseboard-version",
};

#define DMI_COMMAND_LEN_MAX 260
const char *dmidecode_command = "dmidecode";

char *dmistrings[ARRAY_SIZE(dmidecode_names)];

/* Strings longer than 4096 in DMI are just insane. */
#define DMI_MAX_ANSWER_LEN 4096

static char *get_dmi_string(const char *string_name)
{
	FILE *dmidecode_pipe;
	char *result;
	char answerbuf[DMI_MAX_ANSWER_LEN];
	char commandline[DMI_COMMAND_LEN_MAX + 40];

	snprintf(commandline, sizeof(commandline),
		 "%s -s %s", dmidecode_command, string_name);
	dmidecode_pipe = popen(commandline, "r");
	if (!dmidecode_pipe) {
		msg_perr("DMI pipe open error\n");
		return NULL;
	}
	if (!fgets(answerbuf, DMI_MAX_ANSWER_LEN, dmidecode_pipe)) {
		if(ferror(dmidecode_pipe)) {
			msg_perr("DMI pipe read error\n");
			pclose(dmidecode_pipe);
			return NULL;
		} else {
			answerbuf[0] = 0;	/* Hit EOF */
		}
	}
	/* Toss all output above DMI_MAX_ANSWER_LEN away to prevent
	   deadlock on pclose. */
	while (!feof(dmidecode_pipe))
		getc(dmidecode_pipe);
	if (pclose(dmidecode_pipe) != 0) {
		msg_pinfo("dmidecode execution unsucessfull - continuing "
			"without DMI info\n");
		return NULL;
	}

	/* Chomp trailing newline. */
	if (answerbuf[0] != 0 &&
	    answerbuf[strlen(answerbuf) - 1] == '\n')
		answerbuf[strlen(answerbuf) - 1] = 0;
	msg_pdbg("DMI string %s: \"%s\"\n", string_name, answerbuf);

	result = strdup(answerbuf);
	if (!result)
		puts("WARNING: Out of memory - DMI support fails");

	return result;
}

void dmi_init(void)
{
	int i;
	char *chassis_type;

	has_dmi_support = 1;
	for (i = 0; i < ARRAY_SIZE(dmidecode_names); i++) {
		dmistrings[i] = get_dmi_string(dmidecode_names[i]);
		if (!dmistrings[i]) {
			has_dmi_support = 0;
			return;
		}
	}

	chassis_type = get_dmi_string("chassis-type");
	if (chassis_type && (!strcmp(chassis_type, "Notebook") ||
			     !strcmp(chassis_type, "Portable"))) {
		msg_pdbg("Laptop detected via DMI\n");
		is_laptop = 1;
	}
	free(chassis_type);
}

/**
 * Does an substring/prefix/postfix/whole-string match.
 *
 * The pattern is matched as-is. The only metacharacters supported are '^'
 * at the beginning and '$' at the end. So you can look for "^prefix",
 * "suffix$", "substring" or "^complete string$".
 *
 * @param value The string to check.
 * @param pattern The pattern.
 * @return Nonzero if pattern matches.
 */
static int dmi_compare(const char *value, const char *pattern)
{
	int anchored = 0;
	int patternlen;

	msg_pspew("matching %s against %s\n", value, pattern);
	/* The empty string is part of all strings! */
	if (pattern[0] == 0)
		return 1;

	if (pattern[0] == '^') {
		anchored = 1;
		pattern++;
	}

	patternlen = strlen(pattern);
	if (pattern[patternlen - 1] == '$') {
		int valuelen = strlen(value);
		patternlen--;
		if (patternlen > valuelen)
			return 0;

		/* full string match: require same length */
		if (anchored && (valuelen != patternlen))
			return 0;

		/* start character to make ends match */
		value += valuelen - patternlen;
		anchored = 1;
	}

	if (anchored)
		return strncmp(value, pattern, patternlen) == 0;
	else
		return strstr(value, pattern) != NULL;
}

int dmi_match(const char *pattern)
{
	int i;

	if (!has_dmi_support)
		return 0;

	for (i = 0; i < ARRAY_SIZE(dmidecode_names); i++)
		if (dmi_compare(dmistrings[i], pattern))
			return 1;

	return 0;
}

#endif /* STANDALONE */
OpenPOWER on IntegriCloud