xref: /OK3568_Linux_fs/kernel/scripts/dtc/util.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright 2011 The Chromium Authors, All Rights Reserved.
4*4882a593Smuzhiyun  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * util_is_printable_string contributed by
7*4882a593Smuzhiyun  *	Pantelis Antoniou <pantelis.antoniou AT gmail.com>
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <ctype.h>
11*4882a593Smuzhiyun #include <stdio.h>
12*4882a593Smuzhiyun #include <stdlib.h>
13*4882a593Smuzhiyun #include <stdarg.h>
14*4882a593Smuzhiyun #include <string.h>
15*4882a593Smuzhiyun #include <assert.h>
16*4882a593Smuzhiyun #include <inttypes.h>
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun #include <errno.h>
19*4882a593Smuzhiyun #include <fcntl.h>
20*4882a593Smuzhiyun #include <unistd.h>
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #include "libfdt.h"
23*4882a593Smuzhiyun #include "util.h"
24*4882a593Smuzhiyun #include "version_gen.h"
25*4882a593Smuzhiyun 
xstrdup(const char * s)26*4882a593Smuzhiyun char *xstrdup(const char *s)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun 	int len = strlen(s) + 1;
29*4882a593Smuzhiyun 	char *d = xmalloc(len);
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun 	memcpy(d, s, len);
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	return d;
34*4882a593Smuzhiyun }
35*4882a593Smuzhiyun 
xavsprintf_append(char ** strp,const char * fmt,va_list ap)36*4882a593Smuzhiyun int xavsprintf_append(char **strp, const char *fmt, va_list ap)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun 	int n, size = 0;	/* start with 128 bytes */
39*4882a593Smuzhiyun 	char *p;
40*4882a593Smuzhiyun 	va_list ap_copy;
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	p = *strp;
43*4882a593Smuzhiyun 	if (p)
44*4882a593Smuzhiyun 		size = strlen(p);
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	va_copy(ap_copy, ap);
47*4882a593Smuzhiyun 	n = vsnprintf(NULL, 0, fmt, ap_copy) + 1;
48*4882a593Smuzhiyun 	va_end(ap_copy);
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	p = xrealloc(p, size + n);
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	n = vsnprintf(p + size, n, fmt, ap);
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	*strp = p;
55*4882a593Smuzhiyun 	return strlen(p);
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun 
xasprintf_append(char ** strp,const char * fmt,...)58*4882a593Smuzhiyun int xasprintf_append(char **strp, const char *fmt, ...)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun 	int n;
61*4882a593Smuzhiyun 	va_list ap;
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	va_start(ap, fmt);
64*4882a593Smuzhiyun 	n = xavsprintf_append(strp, fmt, ap);
65*4882a593Smuzhiyun 	va_end(ap);
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	return n;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun 
xasprintf(char ** strp,const char * fmt,...)70*4882a593Smuzhiyun int xasprintf(char **strp, const char *fmt, ...)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun 	int n;
73*4882a593Smuzhiyun 	va_list ap;
74*4882a593Smuzhiyun 
75*4882a593Smuzhiyun 	*strp = NULL;
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	va_start(ap, fmt);
78*4882a593Smuzhiyun 	n = xavsprintf_append(strp, fmt, ap);
79*4882a593Smuzhiyun 	va_end(ap);
80*4882a593Smuzhiyun 
81*4882a593Smuzhiyun 	return n;
82*4882a593Smuzhiyun }
83*4882a593Smuzhiyun 
join_path(const char * path,const char * name)84*4882a593Smuzhiyun char *join_path(const char *path, const char *name)
85*4882a593Smuzhiyun {
86*4882a593Smuzhiyun 	int lenp = strlen(path);
87*4882a593Smuzhiyun 	int lenn = strlen(name);
88*4882a593Smuzhiyun 	int len;
89*4882a593Smuzhiyun 	int needslash = 1;
90*4882a593Smuzhiyun 	char *str;
91*4882a593Smuzhiyun 
92*4882a593Smuzhiyun 	len = lenp + lenn + 2;
93*4882a593Smuzhiyun 	if ((lenp > 0) && (path[lenp-1] == '/')) {
94*4882a593Smuzhiyun 		needslash = 0;
95*4882a593Smuzhiyun 		len--;
96*4882a593Smuzhiyun 	}
97*4882a593Smuzhiyun 
98*4882a593Smuzhiyun 	str = xmalloc(len);
99*4882a593Smuzhiyun 	memcpy(str, path, lenp);
100*4882a593Smuzhiyun 	if (needslash) {
101*4882a593Smuzhiyun 		str[lenp] = '/';
102*4882a593Smuzhiyun 		lenp++;
103*4882a593Smuzhiyun 	}
104*4882a593Smuzhiyun 	memcpy(str+lenp, name, lenn+1);
105*4882a593Smuzhiyun 	return str;
106*4882a593Smuzhiyun }
107*4882a593Smuzhiyun 
util_is_printable_string(const void * data,int len)108*4882a593Smuzhiyun bool util_is_printable_string(const void *data, int len)
109*4882a593Smuzhiyun {
110*4882a593Smuzhiyun 	const char *s = data;
111*4882a593Smuzhiyun 	const char *ss, *se;
112*4882a593Smuzhiyun 
113*4882a593Smuzhiyun 	/* zero length is not */
114*4882a593Smuzhiyun 	if (len == 0)
115*4882a593Smuzhiyun 		return 0;
116*4882a593Smuzhiyun 
117*4882a593Smuzhiyun 	/* must terminate with zero */
118*4882a593Smuzhiyun 	if (s[len - 1] != '\0')
119*4882a593Smuzhiyun 		return 0;
120*4882a593Smuzhiyun 
121*4882a593Smuzhiyun 	se = s + len;
122*4882a593Smuzhiyun 
123*4882a593Smuzhiyun 	while (s < se) {
124*4882a593Smuzhiyun 		ss = s;
125*4882a593Smuzhiyun 		while (s < se && *s && isprint((unsigned char)*s))
126*4882a593Smuzhiyun 			s++;
127*4882a593Smuzhiyun 
128*4882a593Smuzhiyun 		/* not zero, or not done yet */
129*4882a593Smuzhiyun 		if (*s != '\0' || s == ss)
130*4882a593Smuzhiyun 			return 0;
131*4882a593Smuzhiyun 
132*4882a593Smuzhiyun 		s++;
133*4882a593Smuzhiyun 	}
134*4882a593Smuzhiyun 
135*4882a593Smuzhiyun 	return 1;
136*4882a593Smuzhiyun }
137*4882a593Smuzhiyun 
138*4882a593Smuzhiyun /*
139*4882a593Smuzhiyun  * Parse a octal encoded character starting at index i in string s.  The
140*4882a593Smuzhiyun  * resulting character will be returned and the index i will be updated to
141*4882a593Smuzhiyun  * point at the character directly after the end of the encoding, this may be
142*4882a593Smuzhiyun  * the '\0' terminator of the string.
143*4882a593Smuzhiyun  */
get_oct_char(const char * s,int * i)144*4882a593Smuzhiyun static char get_oct_char(const char *s, int *i)
145*4882a593Smuzhiyun {
146*4882a593Smuzhiyun 	char x[4];
147*4882a593Smuzhiyun 	char *endx;
148*4882a593Smuzhiyun 	long val;
149*4882a593Smuzhiyun 
150*4882a593Smuzhiyun 	x[3] = '\0';
151*4882a593Smuzhiyun 	strncpy(x, s + *i, 3);
152*4882a593Smuzhiyun 
153*4882a593Smuzhiyun 	val = strtol(x, &endx, 8);
154*4882a593Smuzhiyun 
155*4882a593Smuzhiyun 	assert(endx > x);
156*4882a593Smuzhiyun 
157*4882a593Smuzhiyun 	(*i) += endx - x;
158*4882a593Smuzhiyun 	return val;
159*4882a593Smuzhiyun }
160*4882a593Smuzhiyun 
161*4882a593Smuzhiyun /*
162*4882a593Smuzhiyun  * Parse a hexadecimal encoded character starting at index i in string s.  The
163*4882a593Smuzhiyun  * resulting character will be returned and the index i will be updated to
164*4882a593Smuzhiyun  * point at the character directly after the end of the encoding, this may be
165*4882a593Smuzhiyun  * the '\0' terminator of the string.
166*4882a593Smuzhiyun  */
get_hex_char(const char * s,int * i)167*4882a593Smuzhiyun static char get_hex_char(const char *s, int *i)
168*4882a593Smuzhiyun {
169*4882a593Smuzhiyun 	char x[3];
170*4882a593Smuzhiyun 	char *endx;
171*4882a593Smuzhiyun 	long val;
172*4882a593Smuzhiyun 
173*4882a593Smuzhiyun 	x[2] = '\0';
174*4882a593Smuzhiyun 	strncpy(x, s + *i, 2);
175*4882a593Smuzhiyun 
176*4882a593Smuzhiyun 	val = strtol(x, &endx, 16);
177*4882a593Smuzhiyun 	if (!(endx  > x))
178*4882a593Smuzhiyun 		die("\\x used with no following hex digits\n");
179*4882a593Smuzhiyun 
180*4882a593Smuzhiyun 	(*i) += endx - x;
181*4882a593Smuzhiyun 	return val;
182*4882a593Smuzhiyun }
183*4882a593Smuzhiyun 
get_escape_char(const char * s,int * i)184*4882a593Smuzhiyun char get_escape_char(const char *s, int *i)
185*4882a593Smuzhiyun {
186*4882a593Smuzhiyun 	char	c = s[*i];
187*4882a593Smuzhiyun 	int	j = *i + 1;
188*4882a593Smuzhiyun 	char	val;
189*4882a593Smuzhiyun 
190*4882a593Smuzhiyun 	switch (c) {
191*4882a593Smuzhiyun 	case 'a':
192*4882a593Smuzhiyun 		val = '\a';
193*4882a593Smuzhiyun 		break;
194*4882a593Smuzhiyun 	case 'b':
195*4882a593Smuzhiyun 		val = '\b';
196*4882a593Smuzhiyun 		break;
197*4882a593Smuzhiyun 	case 't':
198*4882a593Smuzhiyun 		val = '\t';
199*4882a593Smuzhiyun 		break;
200*4882a593Smuzhiyun 	case 'n':
201*4882a593Smuzhiyun 		val = '\n';
202*4882a593Smuzhiyun 		break;
203*4882a593Smuzhiyun 	case 'v':
204*4882a593Smuzhiyun 		val = '\v';
205*4882a593Smuzhiyun 		break;
206*4882a593Smuzhiyun 	case 'f':
207*4882a593Smuzhiyun 		val = '\f';
208*4882a593Smuzhiyun 		break;
209*4882a593Smuzhiyun 	case 'r':
210*4882a593Smuzhiyun 		val = '\r';
211*4882a593Smuzhiyun 		break;
212*4882a593Smuzhiyun 	case '0':
213*4882a593Smuzhiyun 	case '1':
214*4882a593Smuzhiyun 	case '2':
215*4882a593Smuzhiyun 	case '3':
216*4882a593Smuzhiyun 	case '4':
217*4882a593Smuzhiyun 	case '5':
218*4882a593Smuzhiyun 	case '6':
219*4882a593Smuzhiyun 	case '7':
220*4882a593Smuzhiyun 		j--; /* need to re-read the first digit as
221*4882a593Smuzhiyun 		      * part of the octal value */
222*4882a593Smuzhiyun 		val = get_oct_char(s, &j);
223*4882a593Smuzhiyun 		break;
224*4882a593Smuzhiyun 	case 'x':
225*4882a593Smuzhiyun 		val = get_hex_char(s, &j);
226*4882a593Smuzhiyun 		break;
227*4882a593Smuzhiyun 	default:
228*4882a593Smuzhiyun 		val = c;
229*4882a593Smuzhiyun 	}
230*4882a593Smuzhiyun 
231*4882a593Smuzhiyun 	(*i) = j;
232*4882a593Smuzhiyun 	return val;
233*4882a593Smuzhiyun }
234*4882a593Smuzhiyun 
utilfdt_read_err(const char * filename,char ** buffp,size_t * len)235*4882a593Smuzhiyun int utilfdt_read_err(const char *filename, char **buffp, size_t *len)
236*4882a593Smuzhiyun {
237*4882a593Smuzhiyun 	int fd = 0;	/* assume stdin */
238*4882a593Smuzhiyun 	char *buf = NULL;
239*4882a593Smuzhiyun 	size_t bufsize = 1024, offset = 0;
240*4882a593Smuzhiyun 	int ret = 0;
241*4882a593Smuzhiyun 
242*4882a593Smuzhiyun 	*buffp = NULL;
243*4882a593Smuzhiyun 	if (strcmp(filename, "-") != 0) {
244*4882a593Smuzhiyun 		fd = open(filename, O_RDONLY);
245*4882a593Smuzhiyun 		if (fd < 0)
246*4882a593Smuzhiyun 			return errno;
247*4882a593Smuzhiyun 	}
248*4882a593Smuzhiyun 
249*4882a593Smuzhiyun 	/* Loop until we have read everything */
250*4882a593Smuzhiyun 	buf = xmalloc(bufsize);
251*4882a593Smuzhiyun 	do {
252*4882a593Smuzhiyun 		/* Expand the buffer to hold the next chunk */
253*4882a593Smuzhiyun 		if (offset == bufsize) {
254*4882a593Smuzhiyun 			bufsize *= 2;
255*4882a593Smuzhiyun 			buf = xrealloc(buf, bufsize);
256*4882a593Smuzhiyun 		}
257*4882a593Smuzhiyun 
258*4882a593Smuzhiyun 		ret = read(fd, &buf[offset], bufsize - offset);
259*4882a593Smuzhiyun 		if (ret < 0) {
260*4882a593Smuzhiyun 			ret = errno;
261*4882a593Smuzhiyun 			break;
262*4882a593Smuzhiyun 		}
263*4882a593Smuzhiyun 		offset += ret;
264*4882a593Smuzhiyun 	} while (ret != 0);
265*4882a593Smuzhiyun 
266*4882a593Smuzhiyun 	/* Clean up, including closing stdin; return errno on error */
267*4882a593Smuzhiyun 	close(fd);
268*4882a593Smuzhiyun 	if (ret)
269*4882a593Smuzhiyun 		free(buf);
270*4882a593Smuzhiyun 	else
271*4882a593Smuzhiyun 		*buffp = buf;
272*4882a593Smuzhiyun 	if (len)
273*4882a593Smuzhiyun 		*len = bufsize;
274*4882a593Smuzhiyun 	return ret;
275*4882a593Smuzhiyun }
276*4882a593Smuzhiyun 
utilfdt_read(const char * filename,size_t * len)277*4882a593Smuzhiyun char *utilfdt_read(const char *filename, size_t *len)
278*4882a593Smuzhiyun {
279*4882a593Smuzhiyun 	char *buff;
280*4882a593Smuzhiyun 	int ret = utilfdt_read_err(filename, &buff, len);
281*4882a593Smuzhiyun 
282*4882a593Smuzhiyun 	if (ret) {
283*4882a593Smuzhiyun 		fprintf(stderr, "Couldn't open blob from '%s': %s\n", filename,
284*4882a593Smuzhiyun 			strerror(ret));
285*4882a593Smuzhiyun 		return NULL;
286*4882a593Smuzhiyun 	}
287*4882a593Smuzhiyun 	/* Successful read */
288*4882a593Smuzhiyun 	return buff;
289*4882a593Smuzhiyun }
290*4882a593Smuzhiyun 
utilfdt_write_err(const char * filename,const void * blob)291*4882a593Smuzhiyun int utilfdt_write_err(const char *filename, const void *blob)
292*4882a593Smuzhiyun {
293*4882a593Smuzhiyun 	int fd = 1;	/* assume stdout */
294*4882a593Smuzhiyun 	int totalsize;
295*4882a593Smuzhiyun 	int offset;
296*4882a593Smuzhiyun 	int ret = 0;
297*4882a593Smuzhiyun 	const char *ptr = blob;
298*4882a593Smuzhiyun 
299*4882a593Smuzhiyun 	if (strcmp(filename, "-") != 0) {
300*4882a593Smuzhiyun 		fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
301*4882a593Smuzhiyun 		if (fd < 0)
302*4882a593Smuzhiyun 			return errno;
303*4882a593Smuzhiyun 	}
304*4882a593Smuzhiyun 
305*4882a593Smuzhiyun 	totalsize = fdt_totalsize(blob);
306*4882a593Smuzhiyun 	offset = 0;
307*4882a593Smuzhiyun 
308*4882a593Smuzhiyun 	while (offset < totalsize) {
309*4882a593Smuzhiyun 		ret = write(fd, ptr + offset, totalsize - offset);
310*4882a593Smuzhiyun 		if (ret < 0) {
311*4882a593Smuzhiyun 			ret = -errno;
312*4882a593Smuzhiyun 			break;
313*4882a593Smuzhiyun 		}
314*4882a593Smuzhiyun 		offset += ret;
315*4882a593Smuzhiyun 	}
316*4882a593Smuzhiyun 	/* Close the file/stdin; return errno on error */
317*4882a593Smuzhiyun 	if (fd != 1)
318*4882a593Smuzhiyun 		close(fd);
319*4882a593Smuzhiyun 	return ret < 0 ? -ret : 0;
320*4882a593Smuzhiyun }
321*4882a593Smuzhiyun 
322*4882a593Smuzhiyun 
utilfdt_write(const char * filename,const void * blob)323*4882a593Smuzhiyun int utilfdt_write(const char *filename, const void *blob)
324*4882a593Smuzhiyun {
325*4882a593Smuzhiyun 	int ret = utilfdt_write_err(filename, blob);
326*4882a593Smuzhiyun 
327*4882a593Smuzhiyun 	if (ret) {
328*4882a593Smuzhiyun 		fprintf(stderr, "Couldn't write blob to '%s': %s\n", filename,
329*4882a593Smuzhiyun 			strerror(ret));
330*4882a593Smuzhiyun 	}
331*4882a593Smuzhiyun 	return ret ? -1 : 0;
332*4882a593Smuzhiyun }
333*4882a593Smuzhiyun 
utilfdt_decode_type(const char * fmt,int * type,int * size)334*4882a593Smuzhiyun int utilfdt_decode_type(const char *fmt, int *type, int *size)
335*4882a593Smuzhiyun {
336*4882a593Smuzhiyun 	int qualifier = 0;
337*4882a593Smuzhiyun 
338*4882a593Smuzhiyun 	if (!*fmt)
339*4882a593Smuzhiyun 		return -1;
340*4882a593Smuzhiyun 
341*4882a593Smuzhiyun 	/* get the conversion qualifier */
342*4882a593Smuzhiyun 	*size = -1;
343*4882a593Smuzhiyun 	if (strchr("hlLb", *fmt)) {
344*4882a593Smuzhiyun 		qualifier = *fmt++;
345*4882a593Smuzhiyun 		if (qualifier == *fmt) {
346*4882a593Smuzhiyun 			switch (*fmt++) {
347*4882a593Smuzhiyun /* TODO:		case 'l': qualifier = 'L'; break;*/
348*4882a593Smuzhiyun 			case 'h':
349*4882a593Smuzhiyun 				qualifier = 'b';
350*4882a593Smuzhiyun 				break;
351*4882a593Smuzhiyun 			}
352*4882a593Smuzhiyun 		}
353*4882a593Smuzhiyun 	}
354*4882a593Smuzhiyun 
355*4882a593Smuzhiyun 	/* we should now have a type */
356*4882a593Smuzhiyun 	if ((*fmt == '\0') || !strchr("iuxs", *fmt))
357*4882a593Smuzhiyun 		return -1;
358*4882a593Smuzhiyun 
359*4882a593Smuzhiyun 	/* convert qualifier (bhL) to byte size */
360*4882a593Smuzhiyun 	if (*fmt != 's')
361*4882a593Smuzhiyun 		*size = qualifier == 'b' ? 1 :
362*4882a593Smuzhiyun 				qualifier == 'h' ? 2 :
363*4882a593Smuzhiyun 				qualifier == 'l' ? 4 : -1;
364*4882a593Smuzhiyun 	*type = *fmt++;
365*4882a593Smuzhiyun 
366*4882a593Smuzhiyun 	/* that should be it! */
367*4882a593Smuzhiyun 	if (*fmt)
368*4882a593Smuzhiyun 		return -1;
369*4882a593Smuzhiyun 	return 0;
370*4882a593Smuzhiyun }
371*4882a593Smuzhiyun 
utilfdt_print_data(const char * data,int len)372*4882a593Smuzhiyun void utilfdt_print_data(const char *data, int len)
373*4882a593Smuzhiyun {
374*4882a593Smuzhiyun 	int i;
375*4882a593Smuzhiyun 	const char *s;
376*4882a593Smuzhiyun 
377*4882a593Smuzhiyun 	/* no data, don't print */
378*4882a593Smuzhiyun 	if (len == 0)
379*4882a593Smuzhiyun 		return;
380*4882a593Smuzhiyun 
381*4882a593Smuzhiyun 	if (util_is_printable_string(data, len)) {
382*4882a593Smuzhiyun 		printf(" = ");
383*4882a593Smuzhiyun 
384*4882a593Smuzhiyun 		s = data;
385*4882a593Smuzhiyun 		do {
386*4882a593Smuzhiyun 			printf("\"%s\"", s);
387*4882a593Smuzhiyun 			s += strlen(s) + 1;
388*4882a593Smuzhiyun 			if (s < data + len)
389*4882a593Smuzhiyun 				printf(", ");
390*4882a593Smuzhiyun 		} while (s < data + len);
391*4882a593Smuzhiyun 
392*4882a593Smuzhiyun 	} else if ((len % 4) == 0) {
393*4882a593Smuzhiyun 		const fdt32_t *cell = (const fdt32_t *)data;
394*4882a593Smuzhiyun 
395*4882a593Smuzhiyun 		printf(" = <");
396*4882a593Smuzhiyun 		for (i = 0, len /= 4; i < len; i++)
397*4882a593Smuzhiyun 			printf("0x%08" PRIx32 "%s", fdt32_to_cpu(cell[i]),
398*4882a593Smuzhiyun 			       i < (len - 1) ? " " : "");
399*4882a593Smuzhiyun 		printf(">");
400*4882a593Smuzhiyun 	} else {
401*4882a593Smuzhiyun 		const unsigned char *p = (const unsigned char *)data;
402*4882a593Smuzhiyun 		printf(" = [");
403*4882a593Smuzhiyun 		for (i = 0; i < len; i++)
404*4882a593Smuzhiyun 			printf("%02x%s", *p++, i < len - 1 ? " " : "");
405*4882a593Smuzhiyun 		printf("]");
406*4882a593Smuzhiyun 	}
407*4882a593Smuzhiyun }
408*4882a593Smuzhiyun 
util_version(void)409*4882a593Smuzhiyun void NORETURN util_version(void)
410*4882a593Smuzhiyun {
411*4882a593Smuzhiyun 	printf("Version: %s\n", DTC_VERSION);
412*4882a593Smuzhiyun 	exit(0);
413*4882a593Smuzhiyun }
414*4882a593Smuzhiyun 
util_usage(const char * errmsg,const char * synopsis,const char * short_opts,struct option const long_opts[],const char * const opts_help[])415*4882a593Smuzhiyun void NORETURN util_usage(const char *errmsg, const char *synopsis,
416*4882a593Smuzhiyun 			 const char *short_opts,
417*4882a593Smuzhiyun 			 struct option const long_opts[],
418*4882a593Smuzhiyun 			 const char * const opts_help[])
419*4882a593Smuzhiyun {
420*4882a593Smuzhiyun 	FILE *fp = errmsg ? stderr : stdout;
421*4882a593Smuzhiyun 	const char a_arg[] = "<arg>";
422*4882a593Smuzhiyun 	size_t a_arg_len = strlen(a_arg) + 1;
423*4882a593Smuzhiyun 	size_t i;
424*4882a593Smuzhiyun 	int optlen;
425*4882a593Smuzhiyun 
426*4882a593Smuzhiyun 	fprintf(fp,
427*4882a593Smuzhiyun 		"Usage: %s\n"
428*4882a593Smuzhiyun 		"\n"
429*4882a593Smuzhiyun 		"Options: -[%s]\n", synopsis, short_opts);
430*4882a593Smuzhiyun 
431*4882a593Smuzhiyun 	/* prescan the --long opt length to auto-align */
432*4882a593Smuzhiyun 	optlen = 0;
433*4882a593Smuzhiyun 	for (i = 0; long_opts[i].name; ++i) {
434*4882a593Smuzhiyun 		/* +1 is for space between --opt and help text */
435*4882a593Smuzhiyun 		int l = strlen(long_opts[i].name) + 1;
436*4882a593Smuzhiyun 		if (long_opts[i].has_arg == a_argument)
437*4882a593Smuzhiyun 			l += a_arg_len;
438*4882a593Smuzhiyun 		if (optlen < l)
439*4882a593Smuzhiyun 			optlen = l;
440*4882a593Smuzhiyun 	}
441*4882a593Smuzhiyun 
442*4882a593Smuzhiyun 	for (i = 0; long_opts[i].name; ++i) {
443*4882a593Smuzhiyun 		/* helps when adding new applets or options */
444*4882a593Smuzhiyun 		assert(opts_help[i] != NULL);
445*4882a593Smuzhiyun 
446*4882a593Smuzhiyun 		/* first output the short flag if it has one */
447*4882a593Smuzhiyun 		if (long_opts[i].val > '~')
448*4882a593Smuzhiyun 			fprintf(fp, "      ");
449*4882a593Smuzhiyun 		else
450*4882a593Smuzhiyun 			fprintf(fp, "  -%c, ", long_opts[i].val);
451*4882a593Smuzhiyun 
452*4882a593Smuzhiyun 		/* then the long flag */
453*4882a593Smuzhiyun 		if (long_opts[i].has_arg == no_argument)
454*4882a593Smuzhiyun 			fprintf(fp, "--%-*s", optlen, long_opts[i].name);
455*4882a593Smuzhiyun 		else
456*4882a593Smuzhiyun 			fprintf(fp, "--%s %s%*s", long_opts[i].name, a_arg,
457*4882a593Smuzhiyun 				(int)(optlen - strlen(long_opts[i].name) - a_arg_len), "");
458*4882a593Smuzhiyun 
459*4882a593Smuzhiyun 		/* finally the help text */
460*4882a593Smuzhiyun 		fprintf(fp, "%s\n", opts_help[i]);
461*4882a593Smuzhiyun 	}
462*4882a593Smuzhiyun 
463*4882a593Smuzhiyun 	if (errmsg) {
464*4882a593Smuzhiyun 		fprintf(fp, "\nError: %s\n", errmsg);
465*4882a593Smuzhiyun 		exit(EXIT_FAILURE);
466*4882a593Smuzhiyun 	} else
467*4882a593Smuzhiyun 		exit(EXIT_SUCCESS);
468*4882a593Smuzhiyun }
469