xref: /openbmc/linux/scripts/dtc/util.h (revision d7a3d85e)
1 #ifndef _UTIL_H
2 #define _UTIL_H
3 
4 #include <stdarg.h>
5 #include <getopt.h>
6 
7 /*
8  * Copyright 2011 The Chromium Authors, All Rights Reserved.
9  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of the
14  * License, or (at your option) any later version.
15  *
16  *  This program is distributed in the hope that it will be useful,
17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  *  General Public License for more details.
20  *
21  *  You should have received a copy of the GNU General Public License
22  *  along with this program; if not, write to the Free Software
23  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
24  *                                                                   USA
25  */
26 
27 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
28 
29 static inline void __attribute__((noreturn)) die(const char *str, ...)
30 {
31 	va_list ap;
32 
33 	va_start(ap, str);
34 	fprintf(stderr, "FATAL ERROR: ");
35 	vfprintf(stderr, str, ap);
36 	exit(1);
37 }
38 
39 static inline void *xmalloc(size_t len)
40 {
41 	void *new = malloc(len);
42 
43 	if (!new)
44 		die("malloc() failed\n");
45 
46 	return new;
47 }
48 
49 static inline void *xrealloc(void *p, size_t len)
50 {
51 	void *new = realloc(p, len);
52 
53 	if (!new)
54 		die("realloc() failed (len=%d)\n", len);
55 
56 	return new;
57 }
58 
59 extern char *xstrdup(const char *s);
60 extern char *join_path(const char *path, const char *name);
61 
62 /**
63  * Check a property of a given length to see if it is all printable and
64  * has a valid terminator. The property can contain either a single string,
65  * or multiple strings each of non-zero length.
66  *
67  * @param data	The string to check
68  * @param len	The string length including terminator
69  * @return 1 if a valid printable string, 0 if not
70  */
71 int util_is_printable_string(const void *data, int len);
72 
73 /*
74  * Parse an escaped character starting at index i in string s.  The resulting
75  * character will be returned and the index i will be updated to point at the
76  * character directly after the end of the encoding, this may be the '\0'
77  * terminator of the string.
78  */
79 char get_escape_char(const char *s, int *i);
80 
81 /**
82  * Read a device tree file into a buffer. This will report any errors on
83  * stderr.
84  *
85  * @param filename	The filename to read, or - for stdin
86  * @return Pointer to allocated buffer containing fdt, or NULL on error
87  */
88 char *utilfdt_read(const char *filename);
89 
90 /**
91  * Like utilfdt_read(), but also passes back the size of the file read.
92  *
93  * @param len		If non-NULL, the amount of data we managed to read
94  */
95 char *utilfdt_read_len(const char *filename, off_t *len);
96 
97 /**
98  * Read a device tree file into a buffer. Does not report errors, but only
99  * returns them. The value returned can be passed to strerror() to obtain
100  * an error message for the user.
101  *
102  * @param filename	The filename to read, or - for stdin
103  * @param buffp		Returns pointer to buffer containing fdt
104  * @return 0 if ok, else an errno value representing the error
105  */
106 int utilfdt_read_err(const char *filename, char **buffp);
107 
108 /**
109  * Like utilfdt_read_err(), but also passes back the size of the file read.
110  *
111  * @param len		If non-NULL, the amount of data we managed to read
112  */
113 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
114 
115 /**
116  * Write a device tree buffer to a file. This will report any errors on
117  * stderr.
118  *
119  * @param filename	The filename to write, or - for stdout
120  * @param blob		Poiner to buffer containing fdt
121  * @return 0 if ok, -1 on error
122  */
123 int utilfdt_write(const char *filename, const void *blob);
124 
125 /**
126  * Write a device tree buffer to a file. Does not report errors, but only
127  * returns them. The value returned can be passed to strerror() to obtain
128  * an error message for the user.
129  *
130  * @param filename	The filename to write, or - for stdout
131  * @param blob		Poiner to buffer containing fdt
132  * @return 0 if ok, else an errno value representing the error
133  */
134 int utilfdt_write_err(const char *filename, const void *blob);
135 
136 /**
137  * Decode a data type string. The purpose of this string
138  *
139  * The string consists of an optional character followed by the type:
140  *	Modifier characters:
141  *		hh or b	1 byte
142  *		h	2 byte
143  *		l	4 byte, default
144  *
145  *	Type character:
146  *		s	string
147  *		i	signed integer
148  *		u	unsigned integer
149  *		x	hex
150  *
151  * TODO: Implement ll modifier (8 bytes)
152  * TODO: Implement o type (octal)
153  *
154  * @param fmt		Format string to process
155  * @param type		Returns type found(s/d/u/x), or 0 if none
156  * @param size		Returns size found(1,2,4,8) or 4 if none
157  * @return 0 if ok, -1 on error (no type given, or other invalid format)
158  */
159 int utilfdt_decode_type(const char *fmt, int *type, int *size);
160 
161 /*
162  * This is a usage message fragment for the -t option. It is the format
163  * supported by utilfdt_decode_type.
164  */
165 
166 #define USAGE_TYPE_MSG \
167 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
168 	"\tOptional modifier prefix:\n" \
169 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
170 
171 /**
172  * Print property data in a readable format to stdout
173  *
174  * Properties that look like strings will be printed as strings. Otherwise
175  * the data will be displayed either as cells (if len is a multiple of 4
176  * bytes) or bytes.
177  *
178  * If len is 0 then this function does nothing.
179  *
180  * @param data	Pointers to property data
181  * @param len	Length of property data
182  */
183 void utilfdt_print_data(const char *data, int len);
184 
185 /**
186  * Show source version and exit
187  */
188 void util_version(void) __attribute__((noreturn));
189 
190 /**
191  * Show usage and exit
192  *
193  * This helps standardize the output of various utils.  You most likely want
194  * to use the usage() helper below rather than call this.
195  *
196  * @param errmsg	If non-NULL, an error message to display
197  * @param synopsis	The initial example usage text (and possible examples)
198  * @param short_opts	The string of short options
199  * @param long_opts	The structure of long options
200  * @param opts_help	An array of help strings (should align with long_opts)
201  */
202 void util_usage(const char *errmsg, const char *synopsis,
203 		const char *short_opts, struct option const long_opts[],
204 		const char * const opts_help[]) __attribute__((noreturn));
205 
206 /**
207  * Show usage and exit
208  *
209  * If you name all your usage variables with usage_xxx, then you can call this
210  * help macro rather than expanding all arguments yourself.
211  *
212  * @param errmsg	If non-NULL, an error message to display
213  */
214 #define usage(errmsg) \
215 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
216 		   usage_long_opts, usage_opts_help)
217 
218 /**
219  * Call getopt_long() with standard options
220  *
221  * Since all util code runs getopt in the same way, provide a helper.
222  */
223 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
224 				       usage_long_opts, NULL)
225 
226 /* Helper for aligning long_opts array */
227 #define a_argument required_argument
228 
229 /* Helper for usage_short_opts string constant */
230 #define USAGE_COMMON_SHORT_OPTS "hV"
231 
232 /* Helper for usage_long_opts option array */
233 #define USAGE_COMMON_LONG_OPTS \
234 	{"help",      no_argument, NULL, 'h'}, \
235 	{"version",   no_argument, NULL, 'V'}, \
236 	{NULL,        no_argument, NULL, 0x0}
237 
238 /* Helper for usage_opts_help array */
239 #define USAGE_COMMON_OPTS_HELP \
240 	"Print this help and exit", \
241 	"Print version and exit", \
242 	NULL
243 
244 /* Helper for getopt case statements */
245 #define case_USAGE_COMMON_FLAGS \
246 	case 'h': usage(NULL); \
247 	case 'V': util_version(); \
248 	case '?': usage("unknown option");
249 
250 #endif /* _UTIL_H */
251