xref: /openbmc/linux/scripts/dtc/util.h (revision 6c33a6f4)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef UTIL_H
3 #define UTIL_H
4 
5 #include <stdarg.h>
6 #include <stdbool.h>
7 #include <getopt.h>
8 
9 /*
10  * Copyright 2011 The Chromium Authors, All Rights Reserved.
11  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
12  */
13 
14 #ifdef __GNUC__
15 #ifdef __clang__
16 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
17 #else
18 #define PRINTF(i, j)	__attribute__((format (gnu_printf, i, j)))
19 #endif
20 #define NORETURN	__attribute__((noreturn))
21 #else
22 #define PRINTF(i, j)
23 #define NORETURN
24 #endif
25 
26 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
27 
28 #define stringify(s)	stringify_(s)
29 #define stringify_(s)	#s
30 
31 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
32 {
33 	va_list ap;
34 
35 	va_start(ap, str);
36 	fprintf(stderr, "FATAL ERROR: ");
37 	vfprintf(stderr, str, ap);
38 	va_end(ap);
39 	exit(1);
40 }
41 
42 static inline void *xmalloc(size_t len)
43 {
44 	void *new = malloc(len);
45 
46 	if (!new)
47 		die("malloc() failed\n");
48 
49 	return new;
50 }
51 
52 static inline void *xrealloc(void *p, size_t len)
53 {
54 	void *new = realloc(p, len);
55 
56 	if (!new)
57 		die("realloc() failed (len=%zd)\n", len);
58 
59 	return new;
60 }
61 
62 extern char *xstrdup(const char *s);
63 
64 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
65 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
66 extern int xavsprintf_append(char **strp, const char *fmt, va_list ap);
67 extern char *join_path(const char *path, const char *name);
68 
69 /**
70  * Check a property of a given length to see if it is all printable and
71  * has a valid terminator. The property can contain either a single string,
72  * or multiple strings each of non-zero length.
73  *
74  * @param data	The string to check
75  * @param len	The string length including terminator
76  * @return 1 if a valid printable string, 0 if not
77  */
78 bool util_is_printable_string(const void *data, int len);
79 
80 /*
81  * Parse an escaped character starting at index i in string s.  The resulting
82  * character will be returned and the index i will be updated to point at the
83  * character directly after the end of the encoding, this may be the '\0'
84  * terminator of the string.
85  */
86 char get_escape_char(const char *s, int *i);
87 
88 /**
89  * Read a device tree file into a buffer. This will report any errors on
90  * stderr.
91  *
92  * @param filename	The filename to read, or - for stdin
93  * @param len		If non-NULL, the amount of data we managed to read
94  * @return Pointer to allocated buffer containing fdt, or NULL on error
95  */
96 char *utilfdt_read(const char *filename, size_t *len);
97 
98 /**
99  * Read a device tree file into a buffer. Does not report errors, but only
100  * returns them. The value returned can be passed to strerror() to obtain
101  * an error message for the user.
102  *
103  * @param filename	The filename to read, or - for stdin
104  * @param buffp		Returns pointer to buffer containing fdt
105  * @param len		If non-NULL, the amount of data we managed to read
106  * @return 0 if ok, else an errno value representing the error
107  */
108 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
109 
110 /**
111  * Write a device tree buffer to a file. This will report any errors on
112  * stderr.
113  *
114  * @param filename	The filename to write, or - for stdout
115  * @param blob		Pointer to buffer containing fdt
116  * @return 0 if ok, -1 on error
117  */
118 int utilfdt_write(const char *filename, const void *blob);
119 
120 /**
121  * Write a device tree buffer to a file. Does not report errors, but only
122  * returns them. The value returned can be passed to strerror() to obtain
123  * an error message for the user.
124  *
125  * @param filename	The filename to write, or - for stdout
126  * @param blob		Pointer to buffer containing fdt
127  * @return 0 if ok, else an errno value representing the error
128  */
129 int utilfdt_write_err(const char *filename, const void *blob);
130 
131 /**
132  * Decode a data type string. The purpose of this string
133  *
134  * The string consists of an optional character followed by the type:
135  *	Modifier characters:
136  *		hh or b	1 byte
137  *		h	2 byte
138  *		l	4 byte, default
139  *
140  *	Type character:
141  *		s	string
142  *		i	signed integer
143  *		u	unsigned integer
144  *		x	hex
145  *
146  * TODO: Implement ll modifier (8 bytes)
147  * TODO: Implement o type (octal)
148  *
149  * @param fmt		Format string to process
150  * @param type		Returns type found(s/d/u/x), or 0 if none
151  * @param size		Returns size found(1,2,4,8) or 4 if none
152  * @return 0 if ok, -1 on error (no type given, or other invalid format)
153  */
154 int utilfdt_decode_type(const char *fmt, int *type, int *size);
155 
156 /*
157  * This is a usage message fragment for the -t option. It is the format
158  * supported by utilfdt_decode_type.
159  */
160 
161 #define USAGE_TYPE_MSG \
162 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
163 	"\tOptional modifier prefix:\n" \
164 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
165 
166 /**
167  * Print property data in a readable format to stdout
168  *
169  * Properties that look like strings will be printed as strings. Otherwise
170  * the data will be displayed either as cells (if len is a multiple of 4
171  * bytes) or bytes.
172  *
173  * If len is 0 then this function does nothing.
174  *
175  * @param data	Pointers to property data
176  * @param len	Length of property data
177  */
178 void utilfdt_print_data(const char *data, int len);
179 
180 /**
181  * Show source version and exit
182  */
183 void NORETURN util_version(void);
184 
185 /**
186  * Show usage and exit
187  *
188  * This helps standardize the output of various utils.  You most likely want
189  * to use the usage() helper below rather than call this.
190  *
191  * @param errmsg	If non-NULL, an error message to display
192  * @param synopsis	The initial example usage text (and possible examples)
193  * @param short_opts	The string of short options
194  * @param long_opts	The structure of long options
195  * @param opts_help	An array of help strings (should align with long_opts)
196  */
197 void NORETURN util_usage(const char *errmsg, const char *synopsis,
198 			 const char *short_opts,
199 			 struct option const long_opts[],
200 			 const char * const opts_help[]);
201 
202 /**
203  * Show usage and exit
204  *
205  * If you name all your usage variables with usage_xxx, then you can call this
206  * help macro rather than expanding all arguments yourself.
207  *
208  * @param errmsg	If non-NULL, an error message to display
209  */
210 #define usage(errmsg) \
211 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
212 		   usage_long_opts, usage_opts_help)
213 
214 /**
215  * Call getopt_long() with standard options
216  *
217  * Since all util code runs getopt in the same way, provide a helper.
218  */
219 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
220 				       usage_long_opts, NULL)
221 
222 /* Helper for aligning long_opts array */
223 #define a_argument required_argument
224 
225 /* Helper for usage_short_opts string constant */
226 #define USAGE_COMMON_SHORT_OPTS "hV"
227 
228 /* Helper for usage_long_opts option array */
229 #define USAGE_COMMON_LONG_OPTS \
230 	{"help",      no_argument, NULL, 'h'}, \
231 	{"version",   no_argument, NULL, 'V'}, \
232 	{NULL,        no_argument, NULL, 0x0}
233 
234 /* Helper for usage_opts_help array */
235 #define USAGE_COMMON_OPTS_HELP \
236 	"Print this help and exit", \
237 	"Print version and exit", \
238 	NULL
239 
240 /* Helper for getopt case statements */
241 #define case_USAGE_COMMON_FLAGS \
242 	case 'h': usage(NULL); \
243 	case 'V': util_version(); \
244 	case '?': usage("unknown option");
245 
246 #endif /* UTIL_H */
247