aboutsummaryrefslogtreecommitdiffstats
path: root/fdtput.c
blob: 72a0058761d519ee95bd85623c9d62cce0a6d44b (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
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
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
/*
 * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 *
 * 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., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <assert.h>
#include <ctype.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <libfdt.h>

#include "util.h"

/* These are the operations we support */
enum oper_type {
	OPER_WRITE_PROP,		/* Write a property in a node */
	OPER_CREATE_NODE,		/* Create a new node */
	OPER_REMOVE_NODE,		/* Delete a node */
	OPER_DELETE_PROP,		/* Delete a property in a node */
};

struct display_info {
	enum oper_type oper;	/* operation to perform */
	int type;		/* data type (s/i/u/x or 0 for default) */
	int size;		/* data size (1/2/4) */
	int verbose;		/* verbose output */
	int auto_path;		/* automatically create all path components */
};


/**
 * Report an error with a particular node.
 *
 * @param name		Node name to report error on
 * @param namelen	Length of node name, or -1 to use entire string
 * @param err		Error number to report (-FDT_ERR_...)
 */
static void report_error(const char *name, int namelen, int err)
{
	if (namelen == -1)
		namelen = strlen(name);
	fprintf(stderr, "Error at '%1.*s': %s\n", namelen, name,
		fdt_strerror(err));
}

/**
 * Encode a series of arguments in a property value.
 *
 * @param disp		Display information / options
 * @param arg		List of arguments from command line
 * @param arg_count	Number of arguments (may be 0)
 * @param valuep	Returns buffer containing value
 * @param value_len	Returns length of value encoded
 */
static int encode_value(struct display_info *disp, char **arg, int arg_count,
			char **valuep, int *value_len)
{
	char *value = NULL;	/* holding area for value */
	int value_size = 0;	/* size of holding area */
	char *ptr;		/* pointer to current value position */
	int len;		/* length of this cell/string/byte */
	int ival;
	int upto;	/* the number of bytes we have written to buf */
	char fmt[3];

	upto = 0;

	if (disp->verbose)
		fprintf(stderr, "Decoding value:\n");

	fmt[0] = '%';
	fmt[1] = disp->type ? disp->type : 'd';
	fmt[2] = '\0';
	for (; arg_count > 0; arg++, arg_count--, upto += len) {
		/* assume integer unless told otherwise */
		if (disp->type == 's')
			len = strlen(*arg) + 1;
		else
			len = disp->size == -1 ? 4 : disp->size;

		/* enlarge our value buffer by a suitable margin if needed */
		if (upto + len > value_size) {
			value_size = (upto + len) + 500;
			value = xrealloc(value, value_size);
		}

		ptr = value + upto;
		if (disp->type == 's') {
			memcpy(ptr, *arg, len);
			if (disp->verbose)
				fprintf(stderr, "\tstring: '%s'\n", ptr);
		} else {
			fdt32_t *iptr = (fdt32_t *)ptr;
			sscanf(*arg, fmt, &ival);
			if (len == 4)
				*iptr = cpu_to_fdt32(ival);
			else
				*ptr = (uint8_t)ival;
			if (disp->verbose) {
				fprintf(stderr, "\t%s: %d\n",
					disp->size == 1 ? "byte" :
					disp->size == 2 ? "short" : "int",
					ival);
			}
		}
	}
	*value_len = upto;
	*valuep = value;
	if (disp->verbose)
		fprintf(stderr, "Value size %d\n", upto);
	return 0;
}

#define ALIGN(x)		(((x) + (FDT_TAGSIZE) - 1) & ~((FDT_TAGSIZE) - 1))

static char *realloc_fdt(char *fdt, int delta)
{
	int new_sz = fdt_totalsize(fdt) + delta;
	fdt = xrealloc(fdt, new_sz);
	fdt_open_into(fdt, fdt, new_sz);
	return fdt;
}

static char *realloc_node(char *fdt, const char *name)
{
	int delta;
	/* FDT_BEGIN_NODE, node name in off_struct and FDT_END_NODE */
	delta = sizeof(struct fdt_node_header) + ALIGN(strlen(name) + 1)
			+ FDT_TAGSIZE;
	return realloc_fdt(fdt, delta);
}

static char *realloc_property(char *fdt, int nodeoffset,
		const char *name, int newlen)
{
	int delta = 0;
	int oldlen = 0;

	if (!fdt_get_property(fdt, nodeoffset, name, &oldlen))
		/* strings + property header */
		delta = sizeof(struct fdt_property) + strlen(name) + 1;

	if (newlen > oldlen)
		/* actual value in off_struct */
		delta += ALIGN(newlen) - ALIGN(oldlen);

	return realloc_fdt(fdt, delta);
}

static int store_key_value(char **blob, const char *node_name,
		const char *property, const char *buf, int len)
{
	int node;
	int err;

	node = fdt_path_offset(*blob, node_name);
	if (node < 0) {
		report_error(node_name, -1, node);
		return -1;
	}

	err = fdt_setprop(*blob, node, property, buf, len);
	if (err == -FDT_ERR_NOSPACE) {
		*blob = realloc_property(*blob, node, property, len);
		err = fdt_setprop(*blob, node, property, buf, len);
	}
	if (err) {
		report_error(property, -1, err);
		return -1;
	}
	return 0;
}

/**
 * Create paths as needed for all components of a path
 *
 * Any components of the path that do not exist are created. Errors are
 * reported.
 *
 * @param blob		FDT blob to write into
 * @param in_path	Path to process
 * @return 0 if ok, -1 on error
 */
static int create_paths(char **blob, const char *in_path)
{
	const char *path = in_path;
	const char *sep;
	int node, offset = 0;

	/* skip leading '/' */
	while (*path == '/')
		path++;

	for (sep = path; *sep; path = sep + 1, offset = node) {
		/* equivalent to strchrnul(), but it requires _GNU_SOURCE */
		sep = strchr(path, '/');
		if (!sep)
			sep = path + strlen(path);

		node = fdt_subnode_offset_namelen(*blob, offset, path,
				sep - path);
		if (node == -FDT_ERR_NOTFOUND) {
			*blob = realloc_node(*blob, path);
			node = fdt_add_subnode_namelen(*blob, offset, path,
						       sep - path);
		}
		if (node < 0) {
			report_error(path, sep - path, node);
			return -1;
		}
	}

	return 0;
}

/**
 * Create a new node in the fdt.
 *
 * This will overwrite the node_name string. Any error is reported.
 *
 * TODO: Perhaps create fdt_path_offset_namelen() so we don't need to do this.
 *
 * @param blob		FDT blob to write into
 * @param node_name	Name of node to create
 * @return new node offset if found, or -1 on failure
 */
static int create_node(char **blob, const char *node_name)
{
	int node = 0;
	char *p;

	p = strrchr(node_name, '/');
	if (!p) {
		report_error(node_name, -1, -FDT_ERR_BADPATH);
		return -1;
	}
	*p = '\0';

	*blob = realloc_node(*blob, p + 1);

	if (p > node_name) {
		node = fdt_path_offset(*blob, node_name);
		if (node < 0) {
			report_error(node_name, -1, node);
			return -1;
		}
	}

	node = fdt_add_subnode(*blob, node, p + 1);
	if (node < 0) {
		report_error(p + 1, -1, node);
		return -1;
	}

	return 0;
}

/**
 * Delete a property of a node in the fdt.
 *
 * @param blob		FDT blob to write into
 * @param node_name	Path to node containing the property to delete
 * @param prop_name	Name of property to delete
 * @return 0 on success, or -1 on failure
 */
static int delete_prop(char *blob, const char *node_name, const char *prop_name)
{
	int node = 0;

	node = fdt_path_offset(blob, node_name);
	if (node < 0) {
		report_error(node_name, -1, node);
		return -1;
	}

	node = fdt_delprop(blob, node, prop_name);
	if (node < 0) {
		report_error(node_name, -1, node);
		return -1;
	}

	return 0;
}

/**
 * Delete a node in the fdt.
 *
 * @param blob		FDT blob to write into
 * @param node_name	Name of node to delete
 * @return 0 on success, or -1 on failure
 */
static int delete_node(char *blob, const char *node_name)
{
	int node = 0;

	node = fdt_path_offset(blob, node_name);
	if (node < 0) {
		report_error(node_name, -1, node);
		return -1;
	}

	node = fdt_del_node(blob, node);
	if (node < 0) {
		report_error(node_name, -1, node);
		return -1;
	}

	return 0;
}

static int do_fdtput(struct display_info *disp, const char *filename,
		    char **arg, int arg_count)
{
	char *value = NULL;
	char *blob;
	char *node;
	int len, ret = 0;

	blob = utilfdt_read(filename);
	if (!blob)
		return -1;

	switch (disp->oper) {
	case OPER_WRITE_PROP:
		/*
		 * Convert the arguments into a single binary value, then
		 * store them into the property.
		 */
		assert(arg_count >= 2);
		if (disp->auto_path && create_paths(&blob, *arg))
			return -1;
		if (encode_value(disp, arg + 2, arg_count - 2, &value, &len) ||
			store_key_value(&blob, *arg, arg[1], value, len))
			ret = -1;
		break;
	case OPER_CREATE_NODE:
		for (; ret >= 0 && arg_count--; arg++) {
			if (disp->auto_path)
				ret = create_paths(&blob, *arg);
			else
				ret = create_node(&blob, *arg);
		}
		break;
	case OPER_REMOVE_NODE:
		for (; ret >= 0 && arg_count--; arg++)
			ret = delete_node(blob, *arg);
		break;
	case OPER_DELETE_PROP:
		node = *arg;
		for (arg++; ret >= 0 && arg_count-- > 1; arg++)
			ret = delete_prop(blob, node, *arg);
		break;
	}
	if (ret >= 0) {
		fdt_pack(blob);
		ret = utilfdt_write(filename, blob);
	}

	free(blob);

	if (value) {
		free(value);
	}

	return ret;
}

/* Usage related data. */
static const char usage_synopsis[] =
	"write a property value to a device tree\n"
	"	fdtput <options> <dt file> <node> <property> [<value>...]\n"
	"	fdtput -c <options> <dt file> [<node>...]\n"
	"	fdtput -r <options> <dt file> [<node>...]\n"
	"	fdtput -d <options> <dt file> <node> [<property>...]\n"
	"\n"
	"The command line arguments are joined together into a single value.\n"
	USAGE_TYPE_MSG;
static const char usage_short_opts[] = "crdpt:v" USAGE_COMMON_SHORT_OPTS;
static struct option const usage_long_opts[] = {
	{"create",           no_argument, NULL, 'c'},
	{"remove",	     no_argument, NULL, 'r'},
	{"delete",	     no_argument, NULL, 'd'},
	{"auto-path",        no_argument, NULL, 'p'},
	{"type",              a_argument, NULL, 't'},
	{"verbose",          no_argument, NULL, 'v'},
	USAGE_COMMON_LONG_OPTS,
};
static const char * const usage_opts_help[] = {
	"Create nodes if they don't already exist",
	"Delete nodes (and any subnodes) if they already exist",
	"Delete properties if they already exist",
	"Automatically create nodes as needed for the node path",
	"Type of data",
	"Display each value decoded from command line",
	USAGE_COMMON_OPTS_HELP
};

int main(int argc, char *argv[])
{
	int opt;
	struct display_info disp;
	char *filename = NULL;

	memset(&disp, '\0', sizeof(disp));
	disp.size = -1;
	disp.oper = OPER_WRITE_PROP;
	while ((opt = util_getopt_long()) != EOF) {
		/*
		 * TODO: add options to:
		 * - rename node
		 * - pack fdt before writing
		 * - set amount of free space when writing
		 */
		switch (opt) {
		case_USAGE_COMMON_FLAGS

		case 'c':
			disp.oper = OPER_CREATE_NODE;
			break;
		case 'r':
			disp.oper = OPER_REMOVE_NODE;
			break;
		case 'd':
			disp.oper = OPER_DELETE_PROP;
			break;
		case 'p':
			disp.auto_path = 1;
			break;
		case 't':
			if (utilfdt_decode_type(optarg, &disp.type,
					&disp.size))
				usage("Invalid type string");
			break;

		case 'v':
			disp.verbose = 1;
			break;
		}
	}

	if (optind < argc)
		filename = argv[optind++];
	if (!filename)
		usage("missing filename");

	argv += optind;
	argc -= optind;

	if (disp.oper == OPER_WRITE_PROP) {
		if (argc < 1)
			usage("missing node");
		if (argc < 2)
			usage("missing property");
	}

	if (disp.oper == OPER_DELETE_PROP)
		if (argc < 1)
			usage("missing node");

	if (do_fdtput(&disp, filename, argv, argc))
		return 1;
	return 0;
}