xref: /linux/scripts/dtc/util.h (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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 #ifdef __GNUC__
29 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
30 #define NORETURN	__attribute__((noreturn))
31 #else
32 #define PRINTF(i, j)
33 #define NORETURN
34 #endif
35 
36 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
37 
38 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
39 {
40 	va_list ap;
41 
42 	va_start(ap, str);
43 	fprintf(stderr, "FATAL ERROR: ");
44 	vfprintf(stderr, str, ap);
45 	va_end(ap);
46 	exit(1);
47 }
48 
49 static inline void *xmalloc(size_t len)
50 {
51 	void *new = malloc(len);
52 
53 	if (!new)
54 		die("malloc() failed\n");
55 
56 	return new;
57 }
58 
59 static inline void *xrealloc(void *p, size_t len)
60 {
61 	void *new = realloc(p, len);
62 
63 	if (!new)
64 		die("realloc() failed (len=%zd)\n", len);
65 
66 	return new;
67 }
68 
69 extern char *xstrdup(const char *s);
70 
71 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
72 extern char *join_path(const char *path, const char *name);
73 
74 /**
75  * Check a property of a given length to see if it is all printable and
76  * has a valid terminator. The property can contain either a single string,
77  * or multiple strings each of non-zero length.
78  *
79  * @param data	The string to check
80  * @param len	The string length including terminator
81  * @return 1 if a valid printable string, 0 if not
82  */
83 bool util_is_printable_string(const void *data, int len);
84 
85 /*
86  * Parse an escaped character starting at index i in string s.  The resulting
87  * character will be returned and the index i will be updated to point at the
88  * character directly after the end of the encoding, this may be the '\0'
89  * terminator of the string.
90  */
91 char get_escape_char(const char *s, int *i);
92 
93 /**
94  * Read a device tree file into a buffer. This will report any errors on
95  * stderr.
96  *
97  * @param filename	The filename to read, or - for stdin
98  * @return Pointer to allocated buffer containing fdt, or NULL on error
99  */
100 char *utilfdt_read(const char *filename);
101 
102 /**
103  * Like utilfdt_read(), but also passes back the size of the file read.
104  *
105  * @param len		If non-NULL, the amount of data we managed to read
106  */
107 char *utilfdt_read_len(const char *filename, off_t *len);
108 
109 /**
110  * Read a device tree file into a buffer. Does not report errors, but only
111  * returns them. The value returned can be passed to strerror() to obtain
112  * an error message for the user.
113  *
114  * @param filename	The filename to read, or - for stdin
115  * @param buffp		Returns pointer to buffer containing fdt
116  * @return 0 if ok, else an errno value representing the error
117  */
118 int utilfdt_read_err(const char *filename, char **buffp);
119 
120 /**
121  * Like utilfdt_read_err(), but also passes back the size of the file read.
122  *
123  * @param len		If non-NULL, the amount of data we managed to read
124  */
125 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
126 
127 /**
128  * Write a device tree buffer to a file. This will report any errors on
129  * stderr.
130  *
131  * @param filename	The filename to write, or - for stdout
132  * @param blob		Poiner to buffer containing fdt
133  * @return 0 if ok, -1 on error
134  */
135 int utilfdt_write(const char *filename, const void *blob);
136 
137 /**
138  * Write a device tree buffer to a file. Does not report errors, but only
139  * returns them. The value returned can be passed to strerror() to obtain
140  * an error message for the user.
141  *
142  * @param filename	The filename to write, or - for stdout
143  * @param blob		Poiner to buffer containing fdt
144  * @return 0 if ok, else an errno value representing the error
145  */
146 int utilfdt_write_err(const char *filename, const void *blob);
147 
148 /**
149  * Decode a data type string. The purpose of this string
150  *
151  * The string consists of an optional character followed by the type:
152  *	Modifier characters:
153  *		hh or b	1 byte
154  *		h	2 byte
155  *		l	4 byte, default
156  *
157  *	Type character:
158  *		s	string
159  *		i	signed integer
160  *		u	unsigned integer
161  *		x	hex
162  *
163  * TODO: Implement ll modifier (8 bytes)
164  * TODO: Implement o type (octal)
165  *
166  * @param fmt		Format string to process
167  * @param type		Returns type found(s/d/u/x), or 0 if none
168  * @param size		Returns size found(1,2,4,8) or 4 if none
169  * @return 0 if ok, -1 on error (no type given, or other invalid format)
170  */
171 int utilfdt_decode_type(const char *fmt, int *type, int *size);
172 
173 /*
174  * This is a usage message fragment for the -t option. It is the format
175  * supported by utilfdt_decode_type.
176  */
177 
178 #define USAGE_TYPE_MSG \
179 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
180 	"\tOptional modifier prefix:\n" \
181 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
182 
183 /**
184  * Print property data in a readable format to stdout
185  *
186  * Properties that look like strings will be printed as strings. Otherwise
187  * the data will be displayed either as cells (if len is a multiple of 4
188  * bytes) or bytes.
189  *
190  * If len is 0 then this function does nothing.
191  *
192  * @param data	Pointers to property data
193  * @param len	Length of property data
194  */
195 void utilfdt_print_data(const char *data, int len);
196 
197 /**
198  * Show source version and exit
199  */
200 void NORETURN util_version(void);
201 
202 /**
203  * Show usage and exit
204  *
205  * This helps standardize the output of various utils.  You most likely want
206  * to use the usage() helper below rather than call this.
207  *
208  * @param errmsg	If non-NULL, an error message to display
209  * @param synopsis	The initial example usage text (and possible examples)
210  * @param short_opts	The string of short options
211  * @param long_opts	The structure of long options
212  * @param opts_help	An array of help strings (should align with long_opts)
213  */
214 void NORETURN util_usage(const char *errmsg, const char *synopsis,
215 			 const char *short_opts,
216 			 struct option const long_opts[],
217 			 const char * const opts_help[]);
218 
219 /**
220  * Show usage and exit
221  *
222  * If you name all your usage variables with usage_xxx, then you can call this
223  * help macro rather than expanding all arguments yourself.
224  *
225  * @param errmsg	If non-NULL, an error message to display
226  */
227 #define usage(errmsg) \
228 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
229 		   usage_long_opts, usage_opts_help)
230 
231 /**
232  * Call getopt_long() with standard options
233  *
234  * Since all util code runs getopt in the same way, provide a helper.
235  */
236 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
237 				       usage_long_opts, NULL)
238 
239 /* Helper for aligning long_opts array */
240 #define a_argument required_argument
241 
242 /* Helper for usage_short_opts string constant */
243 #define USAGE_COMMON_SHORT_OPTS "hV"
244 
245 /* Helper for usage_long_opts option array */
246 #define USAGE_COMMON_LONG_OPTS \
247 	{"help",      no_argument, NULL, 'h'}, \
248 	{"version",   no_argument, NULL, 'V'}, \
249 	{NULL,        no_argument, NULL, 0x0}
250 
251 /* Helper for usage_opts_help array */
252 #define USAGE_COMMON_OPTS_HELP \
253 	"Print this help and exit", \
254 	"Print version and exit", \
255 	NULL
256 
257 /* Helper for getopt case statements */
258 #define case_USAGE_COMMON_FLAGS \
259 	case 'h': usage(NULL); \
260 	case 'V': util_version(); \
261 	case '?': usage("unknown option");
262 
263 #endif /* _UTIL_H */
264