xref: /linux/scripts/dtc/util.h (revision f79e4d5f92a129a1159c973735007d4ddc8541f3)
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 #define stringify(s)	stringify_(s)
39 #define stringify_(s)	#s
40 
41 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
42 {
43 	va_list ap;
44 
45 	va_start(ap, str);
46 	fprintf(stderr, "FATAL ERROR: ");
47 	vfprintf(stderr, str, ap);
48 	va_end(ap);
49 	exit(1);
50 }
51 
52 static inline void *xmalloc(size_t len)
53 {
54 	void *new = malloc(len);
55 
56 	if (!new)
57 		die("malloc() failed\n");
58 
59 	return new;
60 }
61 
62 static inline void *xrealloc(void *p, size_t len)
63 {
64 	void *new = realloc(p, len);
65 
66 	if (!new)
67 		die("realloc() failed (len=%zd)\n", len);
68 
69 	return new;
70 }
71 
72 extern char *xstrdup(const char *s);
73 
74 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
75 extern char *join_path(const char *path, const char *name);
76 
77 /**
78  * Check a property of a given length to see if it is all printable and
79  * has a valid terminator. The property can contain either a single string,
80  * or multiple strings each of non-zero length.
81  *
82  * @param data	The string to check
83  * @param len	The string length including terminator
84  * @return 1 if a valid printable string, 0 if not
85  */
86 bool util_is_printable_string(const void *data, int len);
87 
88 /*
89  * Parse an escaped character starting at index i in string s.  The resulting
90  * character will be returned and the index i will be updated to point at the
91  * character directly after the end of the encoding, this may be the '\0'
92  * terminator of the string.
93  */
94 char get_escape_char(const char *s, int *i);
95 
96 /**
97  * Read a device tree file into a buffer. This will report any errors on
98  * stderr.
99  *
100  * @param filename	The filename to read, or - for stdin
101  * @return Pointer to allocated buffer containing fdt, or NULL on error
102  */
103 char *utilfdt_read(const char *filename);
104 
105 /**
106  * Like utilfdt_read(), but also passes back the size of the file read.
107  *
108  * @param len		If non-NULL, the amount of data we managed to read
109  */
110 char *utilfdt_read_len(const char *filename, off_t *len);
111 
112 /**
113  * Read a device tree file into a buffer. Does not report errors, but only
114  * returns them. The value returned can be passed to strerror() to obtain
115  * an error message for the user.
116  *
117  * @param filename	The filename to read, or - for stdin
118  * @param buffp		Returns pointer to buffer containing fdt
119  * @return 0 if ok, else an errno value representing the error
120  */
121 int utilfdt_read_err(const char *filename, char **buffp);
122 
123 /**
124  * Like utilfdt_read_err(), but also passes back the size of the file read.
125  *
126  * @param len		If non-NULL, the amount of data we managed to read
127  */
128 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
129 
130 /**
131  * Write a device tree buffer to a file. This will report any errors on
132  * stderr.
133  *
134  * @param filename	The filename to write, or - for stdout
135  * @param blob		Poiner to buffer containing fdt
136  * @return 0 if ok, -1 on error
137  */
138 int utilfdt_write(const char *filename, const void *blob);
139 
140 /**
141  * Write a device tree buffer to a file. Does not report errors, but only
142  * returns them. The value returned can be passed to strerror() to obtain
143  * an error message for the user.
144  *
145  * @param filename	The filename to write, or - for stdout
146  * @param blob		Poiner to buffer containing fdt
147  * @return 0 if ok, else an errno value representing the error
148  */
149 int utilfdt_write_err(const char *filename, const void *blob);
150 
151 /**
152  * Decode a data type string. The purpose of this string
153  *
154  * The string consists of an optional character followed by the type:
155  *	Modifier characters:
156  *		hh or b	1 byte
157  *		h	2 byte
158  *		l	4 byte, default
159  *
160  *	Type character:
161  *		s	string
162  *		i	signed integer
163  *		u	unsigned integer
164  *		x	hex
165  *
166  * TODO: Implement ll modifier (8 bytes)
167  * TODO: Implement o type (octal)
168  *
169  * @param fmt		Format string to process
170  * @param type		Returns type found(s/d/u/x), or 0 if none
171  * @param size		Returns size found(1,2,4,8) or 4 if none
172  * @return 0 if ok, -1 on error (no type given, or other invalid format)
173  */
174 int utilfdt_decode_type(const char *fmt, int *type, int *size);
175 
176 /*
177  * This is a usage message fragment for the -t option. It is the format
178  * supported by utilfdt_decode_type.
179  */
180 
181 #define USAGE_TYPE_MSG \
182 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
183 	"\tOptional modifier prefix:\n" \
184 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
185 
186 /**
187  * Print property data in a readable format to stdout
188  *
189  * Properties that look like strings will be printed as strings. Otherwise
190  * the data will be displayed either as cells (if len is a multiple of 4
191  * bytes) or bytes.
192  *
193  * If len is 0 then this function does nothing.
194  *
195  * @param data	Pointers to property data
196  * @param len	Length of property data
197  */
198 void utilfdt_print_data(const char *data, int len);
199 
200 /**
201  * Show source version and exit
202  */
203 void NORETURN util_version(void);
204 
205 /**
206  * Show usage and exit
207  *
208  * This helps standardize the output of various utils.  You most likely want
209  * to use the usage() helper below rather than call this.
210  *
211  * @param errmsg	If non-NULL, an error message to display
212  * @param synopsis	The initial example usage text (and possible examples)
213  * @param short_opts	The string of short options
214  * @param long_opts	The structure of long options
215  * @param opts_help	An array of help strings (should align with long_opts)
216  */
217 void NORETURN util_usage(const char *errmsg, const char *synopsis,
218 			 const char *short_opts,
219 			 struct option const long_opts[],
220 			 const char * const opts_help[]);
221 
222 /**
223  * Show usage and exit
224  *
225  * If you name all your usage variables with usage_xxx, then you can call this
226  * help macro rather than expanding all arguments yourself.
227  *
228  * @param errmsg	If non-NULL, an error message to display
229  */
230 #define usage(errmsg) \
231 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
232 		   usage_long_opts, usage_opts_help)
233 
234 /**
235  * Call getopt_long() with standard options
236  *
237  * Since all util code runs getopt in the same way, provide a helper.
238  */
239 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
240 				       usage_long_opts, NULL)
241 
242 /* Helper for aligning long_opts array */
243 #define a_argument required_argument
244 
245 /* Helper for usage_short_opts string constant */
246 #define USAGE_COMMON_SHORT_OPTS "hV"
247 
248 /* Helper for usage_long_opts option array */
249 #define USAGE_COMMON_LONG_OPTS \
250 	{"help",      no_argument, NULL, 'h'}, \
251 	{"version",   no_argument, NULL, 'V'}, \
252 	{NULL,        no_argument, NULL, 0x0}
253 
254 /* Helper for usage_opts_help array */
255 #define USAGE_COMMON_OPTS_HELP \
256 	"Print this help and exit", \
257 	"Print version and exit", \
258 	NULL
259 
260 /* Helper for getopt case statements */
261 #define case_USAGE_COMMON_FLAGS \
262 	case 'h': usage(NULL); \
263 	case 'V': util_version(); \
264 	case '?': usage("unknown option");
265 
266 #endif /* UTIL_H */
267