xref: /linux/scripts/dtc/util.h (revision 46e6acfe3501fa938af9c5bd730f0020235b08a2)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef UTIL_H
3 #define UTIL_H
4 
5 #include <stdlib.h>
6 #include <stdarg.h>
7 #include <stdbool.h>
8 #include <getopt.h>
9 
10 /*
11  * Copyright 2011 The Chromium Authors, All Rights Reserved.
12  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
13  */
14 
15 #ifdef __GNUC__
16 #ifdef __MINGW_PRINTF_FORMAT
17 #define PRINTF(i, j)	__attribute__((format (__MINGW_PRINTF_FORMAT, i, j)))
18 #elif __GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4)
19 #define PRINTF(i, j)	__attribute__((format (gnu_printf, i, j)))
20 #else
21 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
22 #endif
23 #define NORETURN	__attribute__((noreturn))
24 #else
25 #define PRINTF(i, j)
26 #define NORETURN
27 #endif
28 
29 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
30 
31 #define stringify(s)	stringify_(s)
32 #define stringify_(s)	#s
33 
34 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
35 {
36 	va_list ap;
37 
38 	va_start(ap, str);
39 	fprintf(stderr, "FATAL ERROR: ");
40 	vfprintf(stderr, str, ap);
41 	va_end(ap);
42 	exit(1);
43 }
44 
45 static inline void *xmalloc(size_t len)
46 {
47 	void *new = malloc(len);
48 
49 	if (!new)
50 		die("malloc() failed\n");
51 
52 	return new;
53 }
54 
55 static inline void *xrealloc(void *p, size_t len)
56 {
57 	void *new = realloc(p, len);
58 
59 	if (!new)
60 		die("realloc() failed (len=%zd)\n", len);
61 
62 	return new;
63 }
64 
65 extern char *xstrdup(const char *s);
66 extern char *xstrndup(const char *s, size_t len);
67 
68 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
69 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
70 extern int PRINTF(2, 0) xavsprintf_append(char **strp, const char *fmt, va_list ap);
71 extern char *join_path(const char *path, const char *name);
72 
73 /**
74  * Check a property of a given length to see if it is all printable and
75  * has a valid terminator. The property can contain either a single string,
76  * or multiple strings each of non-zero length.
77  *
78  * @param data	The string to check
79  * @param len	The string length including terminator
80  * @return 1 if a valid printable string, 0 if not
81  */
82 bool util_is_printable_string(const void *data, int len);
83 
84 /*
85  * Parse an escaped character starting at index i in string s.  The resulting
86  * character will be returned and the index i will be updated to point at the
87  * character directly after the end of the encoding, this may be the '\0'
88  * terminator of the string.
89  */
90 char get_escape_char(const char *s, int *i);
91 
92 /**
93  * Read a device tree file into a buffer. This will report any errors on
94  * stderr.
95  *
96  * @param filename	The filename to read, or - for stdin
97  * @param len		If non-NULL, the amount of data we managed to read
98  * @return Pointer to allocated buffer containing fdt, or NULL on error
99  */
100 char *utilfdt_read(const char *filename, size_t *len);
101 
102 /**
103  * Read a device tree file into a buffer. Does not report errors, but only
104  * returns them. The value returned can be passed to strerror() to obtain
105  * an error message for the user.
106  *
107  * @param filename	The filename to read, or - for stdin
108  * @param buffp		Returns pointer to buffer containing fdt
109  * @param len		If non-NULL, the amount of data we managed to read
110  * @return 0 if ok, else an errno value representing the error
111  */
112 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
113 
114 /**
115  * Write a device tree buffer to a file. This will report any errors on
116  * stderr.
117  *
118  * @param filename	The filename to write, or - for stdout
119  * @param blob		Pointer to buffer containing fdt
120  * @return 0 if ok, -1 on error
121  */
122 int utilfdt_write(const char *filename, const void *blob);
123 
124 /**
125  * Write a device tree buffer to a file. Does not report errors, but only
126  * returns them. The value returned can be passed to strerror() to obtain
127  * an error message for the user.
128  *
129  * @param filename	The filename to write, or - for stdout
130  * @param blob		Pointer to buffer containing fdt
131  * @return 0 if ok, else an errno value representing the error
132  */
133 int utilfdt_write_err(const char *filename, const void *blob);
134 
135 /**
136  * Decode a data type string. The purpose of this string
137  *
138  * The string consists of an optional character followed by the type:
139  *	Modifier characters:
140  *		hh or b	1 byte
141  *		h	2 byte
142  *		l	4 byte, default
143  *
144  *	Type character:
145  *		s	string
146  *		i	signed integer
147  *		u	unsigned integer
148  *		x	hex
149  *		r	raw
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, r=raw\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 NORETURN util_version(void);
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 NORETURN util_usage(const char *errmsg, const char *synopsis,
203 			 const char *short_opts,
204 			 struct option const long_opts[],
205 			 const char * const opts_help[]);
206 
207 /**
208  * Show usage and exit
209  *
210  * If you name all your usage variables with usage_xxx, then you can call this
211  * help macro rather than expanding all arguments yourself.
212  *
213  * @param errmsg	If non-NULL, an error message to display
214  */
215 #define usage(errmsg) \
216 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
217 		   usage_long_opts, usage_opts_help)
218 
219 /**
220  * Call getopt_long() with standard options
221  *
222  * Since all util code runs getopt in the same way, provide a helper.
223  */
224 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
225 				       usage_long_opts, NULL)
226 
227 /* Helper for aligning long_opts array */
228 #define a_argument required_argument
229 
230 /* Helper for usage_short_opts string constant */
231 #define USAGE_COMMON_SHORT_OPTS "hV"
232 
233 /* Helper for usage_long_opts option array */
234 #define USAGE_COMMON_LONG_OPTS \
235 	{"help",      no_argument, NULL, 'h'}, \
236 	{"version",   no_argument, NULL, 'V'}, \
237 	{NULL,        no_argument, NULL, 0x0}
238 
239 /* Helper for usage_opts_help array */
240 #define USAGE_COMMON_OPTS_HELP \
241 	"Print this help and exit", \
242 	"Print version and exit", \
243 	NULL
244 
245 /* Helper for getopt case statements */
246 #define case_USAGE_COMMON_FLAGS \
247 	case 'h': usage(NULL); \
248 	case 'V': util_version(); \
249 	case '?': usage("unknown option");
250 
251 #endif /* UTIL_H */
252