xref: /openbmc/linux/scripts/dtc/util.h (revision 174cd4b1)
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 int xasprintf(char **strp, const char *fmt, ...);
63 extern char *join_path(const char *path, const char *name);
64 
65 /**
66  * Check a property of a given length to see if it is all printable and
67  * has a valid terminator. The property can contain either a single string,
68  * or multiple strings each of non-zero length.
69  *
70  * @param data	The string to check
71  * @param len	The string length including terminator
72  * @return 1 if a valid printable string, 0 if not
73  */
74 bool util_is_printable_string(const void *data, int len);
75 
76 /*
77  * Parse an escaped character starting at index i in string s.  The resulting
78  * character will be returned and the index i will be updated to point at the
79  * character directly after the end of the encoding, this may be the '\0'
80  * terminator of the string.
81  */
82 char get_escape_char(const char *s, int *i);
83 
84 /**
85  * Read a device tree file into a buffer. This will report any errors on
86  * stderr.
87  *
88  * @param filename	The filename to read, or - for stdin
89  * @return Pointer to allocated buffer containing fdt, or NULL on error
90  */
91 char *utilfdt_read(const char *filename);
92 
93 /**
94  * Like utilfdt_read(), but also passes back the size of the file read.
95  *
96  * @param len		If non-NULL, the amount of data we managed to read
97  */
98 char *utilfdt_read_len(const char *filename, off_t *len);
99 
100 /**
101  * Read a device tree file into a buffer. Does not report errors, but only
102  * returns them. The value returned can be passed to strerror() to obtain
103  * an error message for the user.
104  *
105  * @param filename	The filename to read, or - for stdin
106  * @param buffp		Returns pointer to buffer containing fdt
107  * @return 0 if ok, else an errno value representing the error
108  */
109 int utilfdt_read_err(const char *filename, char **buffp);
110 
111 /**
112  * Like utilfdt_read_err(), but also passes back the size of the file read.
113  *
114  * @param len		If non-NULL, the amount of data we managed to read
115  */
116 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
117 
118 /**
119  * Write a device tree buffer to a file. This will report any errors on
120  * stderr.
121  *
122  * @param filename	The filename to write, or - for stdout
123  * @param blob		Poiner to buffer containing fdt
124  * @return 0 if ok, -1 on error
125  */
126 int utilfdt_write(const char *filename, const void *blob);
127 
128 /**
129  * Write a device tree buffer to a file. Does not report errors, but only
130  * returns them. The value returned can be passed to strerror() to obtain
131  * an error message for the user.
132  *
133  * @param filename	The filename to write, or - for stdout
134  * @param blob		Poiner to buffer containing fdt
135  * @return 0 if ok, else an errno value representing the error
136  */
137 int utilfdt_write_err(const char *filename, const void *blob);
138 
139 /**
140  * Decode a data type string. The purpose of this string
141  *
142  * The string consists of an optional character followed by the type:
143  *	Modifier characters:
144  *		hh or b	1 byte
145  *		h	2 byte
146  *		l	4 byte, default
147  *
148  *	Type character:
149  *		s	string
150  *		i	signed integer
151  *		u	unsigned integer
152  *		x	hex
153  *
154  * TODO: Implement ll modifier (8 bytes)
155  * TODO: Implement o type (octal)
156  *
157  * @param fmt		Format string to process
158  * @param type		Returns type found(s/d/u/x), or 0 if none
159  * @param size		Returns size found(1,2,4,8) or 4 if none
160  * @return 0 if ok, -1 on error (no type given, or other invalid format)
161  */
162 int utilfdt_decode_type(const char *fmt, int *type, int *size);
163 
164 /*
165  * This is a usage message fragment for the -t option. It is the format
166  * supported by utilfdt_decode_type.
167  */
168 
169 #define USAGE_TYPE_MSG \
170 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
171 	"\tOptional modifier prefix:\n" \
172 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
173 
174 /**
175  * Print property data in a readable format to stdout
176  *
177  * Properties that look like strings will be printed as strings. Otherwise
178  * the data will be displayed either as cells (if len is a multiple of 4
179  * bytes) or bytes.
180  *
181  * If len is 0 then this function does nothing.
182  *
183  * @param data	Pointers to property data
184  * @param len	Length of property data
185  */
186 void utilfdt_print_data(const char *data, int len);
187 
188 /**
189  * Show source version and exit
190  */
191 void util_version(void) __attribute__((noreturn));
192 
193 /**
194  * Show usage and exit
195  *
196  * This helps standardize the output of various utils.  You most likely want
197  * to use the usage() helper below rather than call this.
198  *
199  * @param errmsg	If non-NULL, an error message to display
200  * @param synopsis	The initial example usage text (and possible examples)
201  * @param short_opts	The string of short options
202  * @param long_opts	The structure of long options
203  * @param opts_help	An array of help strings (should align with long_opts)
204  */
205 void util_usage(const char *errmsg, const char *synopsis,
206 		const char *short_opts, struct option const long_opts[],
207 		const char * const opts_help[]) __attribute__((noreturn));
208 
209 /**
210  * Show usage and exit
211  *
212  * If you name all your usage variables with usage_xxx, then you can call this
213  * help macro rather than expanding all arguments yourself.
214  *
215  * @param errmsg	If non-NULL, an error message to display
216  */
217 #define usage(errmsg) \
218 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
219 		   usage_long_opts, usage_opts_help)
220 
221 /**
222  * Call getopt_long() with standard options
223  *
224  * Since all util code runs getopt in the same way, provide a helper.
225  */
226 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
227 				       usage_long_opts, NULL)
228 
229 /* Helper for aligning long_opts array */
230 #define a_argument required_argument
231 
232 /* Helper for usage_short_opts string constant */
233 #define USAGE_COMMON_SHORT_OPTS "hV"
234 
235 /* Helper for usage_long_opts option array */
236 #define USAGE_COMMON_LONG_OPTS \
237 	{"help",      no_argument, NULL, 'h'}, \
238 	{"version",   no_argument, NULL, 'V'}, \
239 	{NULL,        no_argument, NULL, 0x0}
240 
241 /* Helper for usage_opts_help array */
242 #define USAGE_COMMON_OPTS_HELP \
243 	"Print this help and exit", \
244 	"Print version and exit", \
245 	NULL
246 
247 /* Helper for getopt case statements */
248 #define case_USAGE_COMMON_FLAGS \
249 	case 'h': usage(NULL); \
250 	case 'V': util_version(); \
251 	case '?': usage("unknown option");
252 
253 #endif /* _UTIL_H */
254