summaryrefslogtreecommitdiffstats
path: root/dmi.c
blob: 1a598344c77945162081d5a584b796e4d2229720 (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
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
/* DMI (Desktop Management Interface)
   also called
   SMBIOS (System Management BIOS)
*/

#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "common.h"

char *dmidecode_file = NULL;


static const char *cat_BIOS[] = { "Vendor", "Version" };
static const char *cat_System[] = { "Manufacturer", "Product Name", "Version" };
static const char *cat_Base_Board[] = { "Manufacturer", "Product Name", "Version" };

struct category {
	const char *cat_name;
	unsigned int nb_fields;
	const char **fields;
};

static const struct category categories[] = {
	{ "BIOS", psizeof(cat_BIOS), cat_BIOS },
	{ "System", psizeof(cat_System), cat_System },
	{ "Base Board", psizeof(cat_Base_Board), cat_Base_Board },

};
static int nb_categories = psizeof(categories);

struct criterion {
	char *name;
	char *val;
};
struct criteria {
	unsigned int nb;
	struct criterion *criteria;
};

/*********************************************************************************/
static int streq(const char *s1, const char *s2) {
	return strcmp(s1, s2) == 0;
}
static int str_begins_with(const char *s, const char *prefix) {
	return strncmp(s, prefix, strlen(prefix)) == 0;
}
static int remove_suffix_in_place(char *s, const char *suffix) {
	unsigned int l = strlen(s);
	unsigned int l_suffix = strlen(suffix);
	if (l >= l_suffix && streq(s + l - l_suffix, suffix)) {
		s[l - l_suffix] = '\0';
		return 1;
	} else
		return 0;
}
static void remove_ending_spaces(char *s) {
	char *p;
	for (p = s + strlen(s) - 1; p >= s; p--) {
		if (*p != '\n' && *p != '\r' && *p != ' ' && *p != '\t')
			break;
		*p = '\0';
	}
}
static char *skip_leading_spaces(char *s) {
	for (; *s; s++)
		if (*s != '\n' && *s != '\r' && *s != ' ' && *s != '\t')
			break;
	return s;
}

/*********************************************************************************/
static char *get_after_colon(char *s) {
	char *p = strchr(s, ':');
	if (p) {
		*p = '\0';
		return p + (p[1] == ' ' ? 2 : 1);
	} else return NULL;
}

static const struct category *lookup_category(const char *cat_name) {
	int i;
	for (i = 0; i < nb_categories; i++)
		if (streq(categories[i].cat_name, cat_name))
			return &categories[i];
	return NULL;
}

static int lookup_field(const struct category *category, const char *field_name) {
	unsigned int i;
	for (i = 0; i < category->nb_fields; i++)
		if (streq(category->fields[i], field_name))
			return 1;
	return 0;
}

static char *lookup_criteria(struct criteria criteria, const char *field) {
	unsigned int i;
	for (i = 0; i < criteria.nb; i++)
		if (streq(criteria.criteria[i].name, field))
			return criteria.criteria[i].val;
	return NULL;
}

/*********************************************************************************/
static struct criteria criteria_from_dmidecode(void) {
	FILE *f;
	char buf[BUF_SIZE];

	struct criteria r = {0, NULL};
	size_t allocated = MAX_DEVICES;

	if (!(f = dmidecode_file ? fopen(dmidecode_file, "r") : popen("dmidecode", "r"))) {
		perror("dmidecode");
		return r;
	}

	r.criteria = malloc(sizeof(*r.criteria) * MAX_DEVICES);

	const struct category *category = NULL;

	/* dmidecode output is less indented as of 2.7 */
	int tab_level = 1;
        if (fgets(buf, sizeof(buf) - 1, f)) {
		int major, minor;
		if (sscanf(buf, "# dmidecode %d.%d", &major, &minor) == 2 && major >= 2 && minor >= 7)
			tab_level = 0;
	}

	while (fgets(buf, sizeof(buf) - 1, f)) {
		if (!buf[0] || !buf[1] || (tab_level && buf[0] != '\t'))
			; /* don't care */
		else if (buf[tab_level] != '\t') {
			char *s = buf + tab_level;
			if (!str_begins_with(s, "DMI type ")) {
				remove_ending_spaces(s);
				remove_suffix_in_place(s, " Information");
				category = lookup_category(s);
			}
		} else if (category) {
			/* don't even look if we don't have an interesting category */
			char *s = buf + tab_level + 1;
			char *val = get_after_colon(s);
			if (val && lookup_field(category, s)) {
				if (r.nb >= allocated) {
				    allocated = r.nb*2;
				    r.criteria = realloc(r.criteria, sizeof(struct criterion) * allocated);
				}
				struct criterion *criterion = &r.criteria[r.nb++];
				asprintf(&criterion->name, "%s/%s", category->cat_name, s);
				remove_ending_spaces(val);
				criterion->val = strdup(skip_leading_spaces(val));
			}
		}
	}
	if (dmidecode_file ? fclose(f) != 0 : pclose(f) == -1) {
		r.nb = 0;
		return r;
	}
	r.criteria = realloc(r.criteria, sizeof(*r.criteria) * r.nb);

	return r;
}

static void free_criteria(struct criteria criteria) {
	unsigned int i;
	for (i = 0; i < criteria.nb; i++) {
		free(criteria.criteria[i].name);
		free(criteria.criteria[i].val);
	}
	if (criteria.nb) free(criteria.criteria);
	criteria.nb = 0;
}

static struct dmi_entries entries_matching_criteria(struct criteria criteria) {
	fh f;
	char buf[2048];
	int line;
	struct dmi_entries r;
	#define MAX_INDENT 20
	int valid[MAX_INDENT];
	char *constraints[MAX_INDENT];

	enum state { in_constraints, in_implies } state = in_implies;
	int was_a_blank_line = 1;
	size_t allocated = MAX_DEVICES;

	r.nb = 0;
	f = fh_open("dmitable");

#define die(err) do { fprintf(stderr, "%s %d: " err "\n", "dmitable", line); exit(1); } while (0)

	r.entries = malloc(sizeof(*r.entries) * MAX_DEVICES);

#define foreach_indent(min, action) do { int i; for (i = min; i < MAX_INDENT; i++) { action; } } while (0)
	
	foreach_indent(0, valid[i] = 1; constraints[i] = NULL);

	int previous_refine = 0;

	for (line = 1; fh_gets(buf, sizeof(buf) - 1, &f); line++) {
		char *s = skip_leading_spaces(buf);
		if (*s == '#') continue; // skip comments

		if (!*s) {
			was_a_blank_line = 1;
		} else {
			int refine = s - buf;
			if (refine > MAX_INDENT) die("too indented constraints");

			remove_ending_spaces(s);
			if (str_begins_with(s, "=> ")) {
				if (refine != previous_refine) die("\"=>\" must not be indented");
				state = in_implies;
				was_a_blank_line = 0;
				
				if (valid[refine]) {
					if (r.nb >= allocated) {
					    allocated = r.nb*2;
					    r.entries = realloc(r.entries, sizeof(struct criterion) * allocated);
					}
					struct dmi_entry *entry = &r.entries[r.nb++];

					s += strlen("=> ");
					char *val = get_after_colon(s);
					if (!val) die("invalid value");
					asprintf(&entry->module, "%s:%s", s, val);

					char tmp[BUF_SIZE];
					tmp[0] = '\0';

					int i;
					for (i = 0; i <= refine; i++)
						if (constraints[i]) {
							if (i) strncat(tmp, "|", BUF_SIZE);
							strncat(tmp, constraints[i], BUF_SIZE);
						}
					entry->constraints = strdup(tmp);
				}
			} else {
				if (state == in_constraints && refine == previous_refine) die("to refine, indent");
				if (!was_a_blank_line) die("missing empty line");
				state = in_constraints;
				previous_refine = refine;
				was_a_blank_line = 0;

				if (refine == 0 || valid[refine - 1]) {

					char *wanted_val = get_after_colon(s);
					if (!wanted_val) die("bad format");

					char *wanted_val_orig = strdup(wanted_val);
					char *val = lookup_criteria(criteria, s);

					int ok = wanted_val && val && (
						remove_suffix_in_place(wanted_val, ".*") ?
						str_begins_with(val, wanted_val) :
						streq(val, wanted_val));
				
					foreach_indent(refine, valid[i] = ok; ifree(constraints[i]));
					if (ok) 
						constraints[refine] = wanted_val_orig;
					else
						free(wanted_val_orig);

				} /* otherwise no need checking */				
			}			
		}
	}
	foreach_indent(0, ifree(constraints[i]));
	fh_close(&f);

	r.entries = realloc(r.entries, sizeof(*r.entries) * r.nb);
	return r;
}

extern void dmi_entries_free(struct dmi_entries entries) {
	unsigned int i;
	for (i = 0; i < entries.nb; i++) {
		free(entries.entries[i].constraints);
		free(entries.entries[i].module);
	}
	if (entries.nb) free(entries.entries);
	entries.nb = 0;
}

extern struct dmi_entries dmi_probe(void) {
	struct criteria criteria = criteria_from_dmidecode();
	struct dmi_entries entries = entries_matching_criteria(criteria);
	free_criteria(criteria);

	return entries;
}