xref: /linux/scripts/dtc/util.c (revision af873fcecef567abf8a3468b06dd4e4aab46da6d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2011 The Chromium Authors, All Rights Reserved.
4  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
5  *
6  * util_is_printable_string contributed by
7  *	Pantelis Antoniou <pantelis.antoniou AT gmail.com>
8  */
9 
10 #include <ctype.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <stdarg.h>
14 #include <string.h>
15 #include <assert.h>
16 
17 #include <errno.h>
18 #include <fcntl.h>
19 #include <unistd.h>
20 
21 #include "libfdt.h"
22 #include "util.h"
23 #include "version_gen.h"
24 
25 char *xstrdup(const char *s)
26 {
27 	int len = strlen(s) + 1;
28 	char *d = xmalloc(len);
29 
30 	memcpy(d, s, len);
31 
32 	return d;
33 }
34 
35 int xavsprintf_append(char **strp, const char *fmt, va_list ap)
36 {
37 	int n, size = 0;	/* start with 128 bytes */
38 	char *p;
39 	va_list ap_copy;
40 
41 	p = *strp;
42 	if (p)
43 		size = strlen(p);
44 
45 	va_copy(ap_copy, ap);
46 	n = vsnprintf(NULL, 0, fmt, ap_copy) + 1;
47 	va_end(ap_copy);
48 
49 	p = xrealloc(p, size + n);
50 
51 	n = vsnprintf(p + size, n, fmt, ap);
52 
53 	*strp = p;
54 	return strlen(p);
55 }
56 
57 int xasprintf_append(char **strp, const char *fmt, ...)
58 {
59 	int n;
60 	va_list ap;
61 
62 	va_start(ap, fmt);
63 	n = xavsprintf_append(strp, fmt, ap);
64 	va_end(ap);
65 
66 	return n;
67 }
68 
69 int xasprintf(char **strp, const char *fmt, ...)
70 {
71 	int n;
72 	va_list ap;
73 
74 	*strp = NULL;
75 
76 	va_start(ap, fmt);
77 	n = xavsprintf_append(strp, fmt, ap);
78 	va_end(ap);
79 
80 	return n;
81 }
82 
83 char *join_path(const char *path, const char *name)
84 {
85 	int lenp = strlen(path);
86 	int lenn = strlen(name);
87 	int len;
88 	int needslash = 1;
89 	char *str;
90 
91 	len = lenp + lenn + 2;
92 	if ((lenp > 0) && (path[lenp-1] == '/')) {
93 		needslash = 0;
94 		len--;
95 	}
96 
97 	str = xmalloc(len);
98 	memcpy(str, path, lenp);
99 	if (needslash) {
100 		str[lenp] = '/';
101 		lenp++;
102 	}
103 	memcpy(str+lenp, name, lenn+1);
104 	return str;
105 }
106 
107 bool util_is_printable_string(const void *data, int len)
108 {
109 	const char *s = data;
110 	const char *ss, *se;
111 
112 	/* zero length is not */
113 	if (len == 0)
114 		return 0;
115 
116 	/* must terminate with zero */
117 	if (s[len - 1] != '\0')
118 		return 0;
119 
120 	se = s + len;
121 
122 	while (s < se) {
123 		ss = s;
124 		while (s < se && *s && isprint((unsigned char)*s))
125 			s++;
126 
127 		/* not zero, or not done yet */
128 		if (*s != '\0' || s == ss)
129 			return 0;
130 
131 		s++;
132 	}
133 
134 	return 1;
135 }
136 
137 /*
138  * Parse a octal encoded character starting at index i in string s.  The
139  * resulting character will be returned and the index i will be updated to
140  * point at the character directly after the end of the encoding, this may be
141  * the '\0' terminator of the string.
142  */
143 static char get_oct_char(const char *s, int *i)
144 {
145 	char x[4];
146 	char *endx;
147 	long val;
148 
149 	x[3] = '\0';
150 	strncpy(x, s + *i, 3);
151 
152 	val = strtol(x, &endx, 8);
153 
154 	assert(endx > x);
155 
156 	(*i) += endx - x;
157 	return val;
158 }
159 
160 /*
161  * Parse a hexadecimal encoded character starting at index i in string s.  The
162  * resulting character will be returned and the index i will be updated to
163  * point at the character directly after the end of the encoding, this may be
164  * the '\0' terminator of the string.
165  */
166 static char get_hex_char(const char *s, int *i)
167 {
168 	char x[3];
169 	char *endx;
170 	long val;
171 
172 	x[2] = '\0';
173 	strncpy(x, s + *i, 2);
174 
175 	val = strtol(x, &endx, 16);
176 	if (!(endx  > x))
177 		die("\\x used with no following hex digits\n");
178 
179 	(*i) += endx - x;
180 	return val;
181 }
182 
183 char get_escape_char(const char *s, int *i)
184 {
185 	char	c = s[*i];
186 	int	j = *i + 1;
187 	char	val;
188 
189 	switch (c) {
190 	case 'a':
191 		val = '\a';
192 		break;
193 	case 'b':
194 		val = '\b';
195 		break;
196 	case 't':
197 		val = '\t';
198 		break;
199 	case 'n':
200 		val = '\n';
201 		break;
202 	case 'v':
203 		val = '\v';
204 		break;
205 	case 'f':
206 		val = '\f';
207 		break;
208 	case 'r':
209 		val = '\r';
210 		break;
211 	case '0':
212 	case '1':
213 	case '2':
214 	case '3':
215 	case '4':
216 	case '5':
217 	case '6':
218 	case '7':
219 		j--; /* need to re-read the first digit as
220 		      * part of the octal value */
221 		val = get_oct_char(s, &j);
222 		break;
223 	case 'x':
224 		val = get_hex_char(s, &j);
225 		break;
226 	default:
227 		val = c;
228 	}
229 
230 	(*i) = j;
231 	return val;
232 }
233 
234 int utilfdt_read_err(const char *filename, char **buffp, size_t *len)
235 {
236 	int fd = 0;	/* assume stdin */
237 	char *buf = NULL;
238 	size_t bufsize = 1024, offset = 0;
239 	int ret = 0;
240 
241 	*buffp = NULL;
242 	if (strcmp(filename, "-") != 0) {
243 		fd = open(filename, O_RDONLY);
244 		if (fd < 0)
245 			return errno;
246 	}
247 
248 	/* Loop until we have read everything */
249 	buf = xmalloc(bufsize);
250 	do {
251 		/* Expand the buffer to hold the next chunk */
252 		if (offset == bufsize) {
253 			bufsize *= 2;
254 			buf = xrealloc(buf, bufsize);
255 		}
256 
257 		ret = read(fd, &buf[offset], bufsize - offset);
258 		if (ret < 0) {
259 			ret = errno;
260 			break;
261 		}
262 		offset += ret;
263 	} while (ret != 0);
264 
265 	/* Clean up, including closing stdin; return errno on error */
266 	close(fd);
267 	if (ret)
268 		free(buf);
269 	else
270 		*buffp = buf;
271 	if (len)
272 		*len = bufsize;
273 	return ret;
274 }
275 
276 char *utilfdt_read(const char *filename, size_t *len)
277 {
278 	char *buff;
279 	int ret = utilfdt_read_err(filename, &buff, len);
280 
281 	if (ret) {
282 		fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
283 			strerror(ret));
284 		return NULL;
285 	}
286 	/* Successful read */
287 	return buff;
288 }
289 
290 int utilfdt_write_err(const char *filename, const void *blob)
291 {
292 	int fd = 1;	/* assume stdout */
293 	int totalsize;
294 	int offset;
295 	int ret = 0;
296 	const char *ptr = blob;
297 
298 	if (strcmp(filename, "-") != 0) {
299 		fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
300 		if (fd < 0)
301 			return errno;
302 	}
303 
304 	totalsize = fdt_totalsize(blob);
305 	offset = 0;
306 
307 	while (offset < totalsize) {
308 		ret = write(fd, ptr + offset, totalsize - offset);
309 		if (ret < 0) {
310 			ret = -errno;
311 			break;
312 		}
313 		offset += ret;
314 	}
315 	/* Close the file/stdin; return errno on error */
316 	if (fd != 1)
317 		close(fd);
318 	return ret < 0 ? -ret : 0;
319 }
320 
321 
322 int utilfdt_write(const char *filename, const void *blob)
323 {
324 	int ret = utilfdt_write_err(filename, blob);
325 
326 	if (ret) {
327 		fprintf(stderr, "Couldn't write blob to '%s': %s\n", filename,
328 			strerror(ret));
329 	}
330 	return ret ? -1 : 0;
331 }
332 
333 int utilfdt_decode_type(const char *fmt, int *type, int *size)
334 {
335 	int qualifier = 0;
336 
337 	if (!*fmt)
338 		return -1;
339 
340 	/* get the conversion qualifier */
341 	*size = -1;
342 	if (strchr("hlLb", *fmt)) {
343 		qualifier = *fmt++;
344 		if (qualifier == *fmt) {
345 			switch (*fmt++) {
346 /* TODO:		case 'l': qualifier = 'L'; break;*/
347 			case 'h':
348 				qualifier = 'b';
349 				break;
350 			}
351 		}
352 	}
353 
354 	/* we should now have a type */
355 	if ((*fmt == '\0') || !strchr("iuxs", *fmt))
356 		return -1;
357 
358 	/* convert qualifier (bhL) to byte size */
359 	if (*fmt != 's')
360 		*size = qualifier == 'b' ? 1 :
361 				qualifier == 'h' ? 2 :
362 				qualifier == 'l' ? 4 : -1;
363 	*type = *fmt++;
364 
365 	/* that should be it! */
366 	if (*fmt)
367 		return -1;
368 	return 0;
369 }
370 
371 void utilfdt_print_data(const char *data, int len)
372 {
373 	int i;
374 	const char *s;
375 
376 	/* no data, don't print */
377 	if (len == 0)
378 		return;
379 
380 	if (util_is_printable_string(data, len)) {
381 		printf(" = ");
382 
383 		s = data;
384 		do {
385 			printf("\"%s\"", s);
386 			s += strlen(s) + 1;
387 			if (s < data + len)
388 				printf(", ");
389 		} while (s < data + len);
390 
391 	} else if ((len % 4) == 0) {
392 		const fdt32_t *cell = (const fdt32_t *)data;
393 
394 		printf(" = <");
395 		for (i = 0, len /= 4; i < len; i++)
396 			printf("0x%08x%s", fdt32_to_cpu(cell[i]),
397 			       i < (len - 1) ? " " : "");
398 		printf(">");
399 	} else {
400 		const unsigned char *p = (const unsigned char *)data;
401 		printf(" = [");
402 		for (i = 0; i < len; i++)
403 			printf("%02x%s", *p++, i < len - 1 ? " " : "");
404 		printf("]");
405 	}
406 }
407 
408 void NORETURN util_version(void)
409 {
410 	printf("Version: %s\n", DTC_VERSION);
411 	exit(0);
412 }
413 
414 void NORETURN util_usage(const char *errmsg, const char *synopsis,
415 			 const char *short_opts,
416 			 struct option const long_opts[],
417 			 const char * const opts_help[])
418 {
419 	FILE *fp = errmsg ? stderr : stdout;
420 	const char a_arg[] = "<arg>";
421 	size_t a_arg_len = strlen(a_arg) + 1;
422 	size_t i;
423 	int optlen;
424 
425 	fprintf(fp,
426 		"Usage: %s\n"
427 		"\n"
428 		"Options: -[%s]\n", synopsis, short_opts);
429 
430 	/* prescan the --long opt length to auto-align */
431 	optlen = 0;
432 	for (i = 0; long_opts[i].name; ++i) {
433 		/* +1 is for space between --opt and help text */
434 		int l = strlen(long_opts[i].name) + 1;
435 		if (long_opts[i].has_arg == a_argument)
436 			l += a_arg_len;
437 		if (optlen < l)
438 			optlen = l;
439 	}
440 
441 	for (i = 0; long_opts[i].name; ++i) {
442 		/* helps when adding new applets or options */
443 		assert(opts_help[i] != NULL);
444 
445 		/* first output the short flag if it has one */
446 		if (long_opts[i].val > '~')
447 			fprintf(fp, "      ");
448 		else
449 			fprintf(fp, "  -%c, ", long_opts[i].val);
450 
451 		/* then the long flag */
452 		if (long_opts[i].has_arg == no_argument)
453 			fprintf(fp, "--%-*s", optlen, long_opts[i].name);
454 		else
455 			fprintf(fp, "--%s %s%*s", long_opts[i].name, a_arg,
456 				(int)(optlen - strlen(long_opts[i].name) - a_arg_len), "");
457 
458 		/* finally the help text */
459 		fprintf(fp, "%s\n", opts_help[i]);
460 	}
461 
462 	if (errmsg) {
463 		fprintf(fp, "\nError: %s\n", errmsg);
464 		exit(EXIT_FAILURE);
465 	} else
466 		exit(EXIT_SUCCESS);
467 }
468