xref: /linux/scripts/dtc/util.h (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 #ifndef _UTIL_H
2 #define _UTIL_H
3 
4 #include <stdarg.h>
5 #include <stdbool.h>
6 #include <getopt.h>
7 
8 /*
9  * Copyright 2011 The Chromium Authors, All Rights Reserved.
10  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of the
15  * License, or (at your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; if not, write to the Free Software
24  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
25  *                                                                   USA
26  */
27 
28 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
29 
30 static inline void __attribute__((noreturn)) die(const char *str, ...)
31 {
32 	va_list ap;
33 
34 	va_start(ap, str);
35 	fprintf(stderr, "FATAL ERROR: ");
36 	vfprintf(stderr, str, ap);
37 	va_end(ap);
38 	exit(1);
39 }
40 
41 static inline void *xmalloc(size_t len)
42 {
43 	void *new = malloc(len);
44 
45 	if (!new)
46 		die("malloc() failed\n");
47 
48 	return new;
49 }
50 
51 static inline void *xrealloc(void *p, size_t len)
52 {
53 	void *new = realloc(p, len);
54 
55 	if (!new)
56 		die("realloc() failed (len=%d)\n", len);
57 
58 	return new;
59 }
60 
61 extern char *xstrdup(const char *s);
62 extern char *join_path(const char *path, const char *name);
63 
64 /**
65  * Check a property of a given length to see if it is all printable and
66  * has a valid terminator. The property can contain either a single string,
67  * or multiple strings each of non-zero length.
68  *
69  * @param data	The string to check
70  * @param len	The string length including terminator
71  * @return 1 if a valid printable string, 0 if not
72  */
73 bool util_is_printable_string(const void *data, int len);
74 
75 /*
76  * Parse an escaped character starting at index i in string s.  The resulting
77  * character will be returned and the index i will be updated to point at the
78  * character directly after the end of the encoding, this may be the '\0'
79  * terminator of the string.
80  */
81 char get_escape_char(const char *s, int *i);
82 
83 /**
84  * Read a device tree file into a buffer. This will report any errors on
85  * stderr.
86  *
87  * @param filename	The filename to read, or - for stdin
88  * @return Pointer to allocated buffer containing fdt, or NULL on error
89  */
90 char *utilfdt_read(const char *filename);
91 
92 /**
93  * Like utilfdt_read(), but also passes back the size of the file read.
94  *
95  * @param len		If non-NULL, the amount of data we managed to read
96  */
97 char *utilfdt_read_len(const char *filename, off_t *len);
98 
99 /**
100  * Read a device tree file into a buffer. Does not report errors, but only
101  * returns them. The value returned can be passed to strerror() to obtain
102  * an error message for the user.
103  *
104  * @param filename	The filename to read, or - for stdin
105  * @param buffp		Returns pointer to buffer containing fdt
106  * @return 0 if ok, else an errno value representing the error
107  */
108 int utilfdt_read_err(const char *filename, char **buffp);
109 
110 /**
111  * Like utilfdt_read_err(), but also passes back the size of the file read.
112  *
113  * @param len		If non-NULL, the amount of data we managed to read
114  */
115 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
116 
117 /**
118  * Write a device tree buffer to a file. This will report any errors on
119  * stderr.
120  *
121  * @param filename	The filename to write, or - for stdout
122  * @param blob		Poiner to buffer containing fdt
123  * @return 0 if ok, -1 on error
124  */
125 int utilfdt_write(const char *filename, const void *blob);
126 
127 /**
128  * Write a device tree buffer to a file. Does not report errors, but only
129  * returns them. The value returned can be passed to strerror() to obtain
130  * an error message for the user.
131  *
132  * @param filename	The filename to write, or - for stdout
133  * @param blob		Poiner to buffer containing fdt
134  * @return 0 if ok, else an errno value representing the error
135  */
136 int utilfdt_write_err(const char *filename, const void *blob);
137 
138 /**
139  * Decode a data type string. The purpose of this string
140  *
141  * The string consists of an optional character followed by the type:
142  *	Modifier characters:
143  *		hh or b	1 byte
144  *		h	2 byte
145  *		l	4 byte, default
146  *
147  *	Type character:
148  *		s	string
149  *		i	signed integer
150  *		u	unsigned integer
151  *		x	hex
152  *
153  * TODO: Implement ll modifier (8 bytes)
154  * TODO: Implement o type (octal)
155  *
156  * @param fmt		Format string to process
157  * @param type		Returns type found(s/d/u/x), or 0 if none
158  * @param size		Returns size found(1,2,4,8) or 4 if none
159  * @return 0 if ok, -1 on error (no type given, or other invalid format)
160  */
161 int utilfdt_decode_type(const char *fmt, int *type, int *size);
162 
163 /*
164  * This is a usage message fragment for the -t option. It is the format
165  * supported by utilfdt_decode_type.
166  */
167 
168 #define USAGE_TYPE_MSG \
169 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
170 	"\tOptional modifier prefix:\n" \
171 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
172 
173 /**
174  * Print property data in a readable format to stdout
175  *
176  * Properties that look like strings will be printed as strings. Otherwise
177  * the data will be displayed either as cells (if len is a multiple of 4
178  * bytes) or bytes.
179  *
180  * If len is 0 then this function does nothing.
181  *
182  * @param data	Pointers to property data
183  * @param len	Length of property data
184  */
185 void utilfdt_print_data(const char *data, int len);
186 
187 /**
188  * Show source version and exit
189  */
190 void util_version(void) __attribute__((noreturn));
191 
192 /**
193  * Show usage and exit
194  *
195  * This helps standardize the output of various utils.  You most likely want
196  * to use the usage() helper below rather than call this.
197  *
198  * @param errmsg	If non-NULL, an error message to display
199  * @param synopsis	The initial example usage text (and possible examples)
200  * @param short_opts	The string of short options
201  * @param long_opts	The structure of long options
202  * @param opts_help	An array of help strings (should align with long_opts)
203  */
204 void util_usage(const char *errmsg, const char *synopsis,
205 		const char *short_opts, struct option const long_opts[],
206 		const char * const opts_help[]) __attribute__((noreturn));
207 
208 /**
209  * Show usage and exit
210  *
211  * If you name all your usage variables with usage_xxx, then you can call this
212  * help macro rather than expanding all arguments yourself.
213  *
214  * @param errmsg	If non-NULL, an error message to display
215  */
216 #define usage(errmsg) \
217 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
218 		   usage_long_opts, usage_opts_help)
219 
220 /**
221  * Call getopt_long() with standard options
222  *
223  * Since all util code runs getopt in the same way, provide a helper.
224  */
225 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
226 				       usage_long_opts, NULL)
227 
228 /* Helper for aligning long_opts array */
229 #define a_argument required_argument
230 
231 /* Helper for usage_short_opts string constant */
232 #define USAGE_COMMON_SHORT_OPTS "hV"
233 
234 /* Helper for usage_long_opts option array */
235 #define USAGE_COMMON_LONG_OPTS \
236 	{"help",      no_argument, NULL, 'h'}, \
237 	{"version",   no_argument, NULL, 'V'}, \
238 	{NULL,        no_argument, NULL, 0x0}
239 
240 /* Helper for usage_opts_help array */
241 #define USAGE_COMMON_OPTS_HELP \
242 	"Print this help and exit", \
243 	"Print version and exit", \
244 	NULL
245 
246 /* Helper for getopt case statements */
247 #define case_USAGE_COMMON_FLAGS \
248 	case 'h': usage(NULL); \
249 	case 'V': util_version(); \
250 	case '?': usage("unknown option");
251 
252 #endif /* _UTIL_H */
253