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 #if __GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4)
17 #define PRINTF(i, j)	__attribute__((format (gnu_printf, i, j)))
18 #else
19 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
20 #endif
21 #define NORETURN	__attribute__((noreturn))
22 #else
23 #define PRINTF(i, j)
24 #define NORETURN
25 #endif
26 
27 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
28 
29 #define stringify(s)	stringify_(s)
30 #define stringify_(s)	#s
31 
die(const char * str,...)32 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
33 {
34 	va_list ap;
35 
36 	va_start(ap, str);
37 	fprintf(stderr, "FATAL ERROR: ");
38 	vfprintf(stderr, str, ap);
39 	va_end(ap);
40 	exit(1);
41 }
42 
xmalloc(size_t len)43 static inline void *xmalloc(size_t len)
44 {
45 	void *new = malloc(len);
46 
47 	if (!new)
48 		die("malloc() failed\n");
49 
50 	return new;
51 }
52 
xrealloc(void * p,size_t len)53 static inline void *xrealloc(void *p, size_t len)
54 {
55 	void *new = realloc(p, len);
56 
57 	if (!new)
58 		die("realloc() failed (len=%zd)\n", len);
59 
60 	return new;
61 }
62 
63 extern char *xstrdup(const char *s);
64 extern char *xstrndup(const char *s, size_t len);
65 
66 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
67 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
68 extern int xavsprintf_append(char **strp, const char *fmt, va_list ap);
69 extern char *join_path(const char *path, const char *name);
70 
71 /**
72  * Check a property of a given length to see if it is all printable and
73  * has a valid terminator. The property can contain either a single string,
74  * or multiple strings each of non-zero length.
75  *
76  * @param data	The string to check
77  * @param len	The string length including terminator
78  * @return 1 if a valid printable string, 0 if not
79  */
80 bool util_is_printable_string(const void *data, int len);
81 
82 /*
83  * Parse an escaped character starting at index i in string s.  The resulting
84  * character will be returned and the index i will be updated to point at the
85  * character directly after the end of the encoding, this may be the '\0'
86  * terminator of the string.
87  */
88 char get_escape_char(const char *s, int *i);
89 
90 /**
91  * Read a device tree file into a buffer. This will report any errors on
92  * stderr.
93  *
94  * @param filename	The filename to read, or - for stdin
95  * @param len		If non-NULL, the amount of data we managed to read
96  * @return Pointer to allocated buffer containing fdt, or NULL on error
97  */
98 char *utilfdt_read(const char *filename, size_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  * @param len		If non-NULL, the amount of data we managed to read
108  * @return 0 if ok, else an errno value representing the error
109  */
110 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
111 
112 /**
113  * Write a device tree buffer to a file. This will report any errors on
114  * stderr.
115  *
116  * @param filename	The filename to write, or - for stdout
117  * @param blob		Pointer to buffer containing fdt
118  * @return 0 if ok, -1 on error
119  */
120 int utilfdt_write(const char *filename, const void *blob);
121 
122 /**
123  * Write a device tree buffer to a file. Does not report errors, but only
124  * returns them. The value returned can be passed to strerror() to obtain
125  * an error message for the user.
126  *
127  * @param filename	The filename to write, or - for stdout
128  * @param blob		Pointer to buffer containing fdt
129  * @return 0 if ok, else an errno value representing the error
130  */
131 int utilfdt_write_err(const char *filename, const void *blob);
132 
133 /**
134  * Decode a data type string. The purpose of this string
135  *
136  * The string consists of an optional character followed by the type:
137  *	Modifier characters:
138  *		hh or b	1 byte
139  *		h	2 byte
140  *		l	4 byte, default
141  *
142  *	Type character:
143  *		s	string
144  *		i	signed integer
145  *		u	unsigned integer
146  *		x	hex
147  *		r	raw
148  *
149  * TODO: Implement ll modifier (8 bytes)
150  * TODO: Implement o type (octal)
151  *
152  * @param fmt		Format string to process
153  * @param type		Returns type found(s/d/u/x), or 0 if none
154  * @param size		Returns size found(1,2,4,8) or 4 if none
155  * @return 0 if ok, -1 on error (no type given, or other invalid format)
156  */
157 int utilfdt_decode_type(const char *fmt, int *type, int *size);
158 
159 /*
160  * This is a usage message fragment for the -t option. It is the format
161  * supported by utilfdt_decode_type.
162  */
163 
164 #define USAGE_TYPE_MSG \
165 	"<type>\ts=string, i=int, u=unsigned, x=hex, r=raw\n" \
166 	"\tOptional modifier prefix:\n" \
167 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
168 
169 /**
170  * Print property data in a readable format to stdout
171  *
172  * Properties that look like strings will be printed as strings. Otherwise
173  * the data will be displayed either as cells (if len is a multiple of 4
174  * bytes) or bytes.
175  *
176  * If len is 0 then this function does nothing.
177  *
178  * @param data	Pointers to property data
179  * @param len	Length of property data
180  */
181 void utilfdt_print_data(const char *data, int len);
182 
183 /**
184  * Show source version and exit
185  */
186 void NORETURN util_version(void);
187 
188 /**
189  * Show usage and exit
190  *
191  * This helps standardize the output of various utils.  You most likely want
192  * to use the usage() helper below rather than call this.
193  *
194  * @param errmsg	If non-NULL, an error message to display
195  * @param synopsis	The initial example usage text (and possible examples)
196  * @param short_opts	The string of short options
197  * @param long_opts	The structure of long options
198  * @param opts_help	An array of help strings (should align with long_opts)
199  */
200 void NORETURN util_usage(const char *errmsg, const char *synopsis,
201 			 const char *short_opts,
202 			 struct option const long_opts[],
203 			 const char * const opts_help[]);
204 
205 /**
206  * Show usage and exit
207  *
208  * If you name all your usage variables with usage_xxx, then you can call this
209  * help macro rather than expanding all arguments yourself.
210  *
211  * @param errmsg	If non-NULL, an error message to display
212  */
213 #define usage(errmsg) \
214 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
215 		   usage_long_opts, usage_opts_help)
216 
217 /**
218  * Call getopt_long() with standard options
219  *
220  * Since all util code runs getopt in the same way, provide a helper.
221  */
222 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
223 				       usage_long_opts, NULL)
224 
225 /* Helper for aligning long_opts array */
226 #define a_argument required_argument
227 
228 /* Helper for usage_short_opts string constant */
229 #define USAGE_COMMON_SHORT_OPTS "hV"
230 
231 /* Helper for usage_long_opts option array */
232 #define USAGE_COMMON_LONG_OPTS \
233 	{"help",      no_argument, NULL, 'h'}, \
234 	{"version",   no_argument, NULL, 'V'}, \
235 	{NULL,        no_argument, NULL, 0x0}
236 
237 /* Helper for usage_opts_help array */
238 #define USAGE_COMMON_OPTS_HELP \
239 	"Print this help and exit", \
240 	"Print version and exit", \
241 	NULL
242 
243 /* Helper for getopt case statements */
244 #define case_USAGE_COMMON_FLAGS \
245 	case 'h': usage(NULL); \
246 	case 'V': util_version(); \
247 	case '?': usage("unknown option");
248 
249 #endif /* UTIL_H */
250