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 __clang__
17 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
18 #else
19 #define PRINTF(i, j)	__attribute__((format (gnu_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 
65 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
66 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
67 extern int xavsprintf_append(char **strp, const char *fmt, va_list ap);
68 extern char *join_path(const char *path, const char *name);
69 
70 /**
71  * Check a property of a given length to see if it is all printable and
72  * has a valid terminator. The property can contain either a single string,
73  * or multiple strings each of non-zero length.
74  *
75  * @param data	The string to check
76  * @param len	The string length including terminator
77  * @return 1 if a valid printable string, 0 if not
78  */
79 bool util_is_printable_string(const void *data, int len);
80 
81 /*
82  * Parse an escaped character starting at index i in string s.  The resulting
83  * character will be returned and the index i will be updated to point at the
84  * character directly after the end of the encoding, this may be the '\0'
85  * terminator of the string.
86  */
87 char get_escape_char(const char *s, int *i);
88 
89 /**
90  * Read a device tree file into a buffer. This will report any errors on
91  * stderr.
92  *
93  * @param filename	The filename to read, or - for stdin
94  * @param len		If non-NULL, the amount of data we managed to read
95  * @return Pointer to allocated buffer containing fdt, or NULL on error
96  */
97 char *utilfdt_read(const char *filename, size_t *len);
98 
99 /**
100  * Read a device tree file into a buffer. Does not report errors, but only
101  * returns them. The value returned can be passed to strerror() to obtain
102  * an error message for the user.
103  *
104  * @param filename	The filename to read, or - for stdin
105  * @param buffp		Returns pointer to buffer containing fdt
106  * @param len		If non-NULL, the amount of data we managed to read
107  * @return 0 if ok, else an errno value representing the error
108  */
109 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
110 
111 /**
112  * Write a device tree buffer to a file. This will report any errors on
113  * stderr.
114  *
115  * @param filename	The filename to write, or - for stdout
116  * @param blob		Pointer to buffer containing fdt
117  * @return 0 if ok, -1 on error
118  */
119 int utilfdt_write(const char *filename, const void *blob);
120 
121 /**
122  * Write a device tree buffer to a file. Does not report errors, but only
123  * returns them. The value returned can be passed to strerror() to obtain
124  * an error message for the user.
125  *
126  * @param filename	The filename to write, or - for stdout
127  * @param blob		Pointer to buffer containing fdt
128  * @return 0 if ok, else an errno value representing the error
129  */
130 int utilfdt_write_err(const char *filename, const void *blob);
131 
132 /**
133  * Decode a data type string. The purpose of this string
134  *
135  * The string consists of an optional character followed by the type:
136  *	Modifier characters:
137  *		hh or b	1 byte
138  *		h	2 byte
139  *		l	4 byte, default
140  *
141  *	Type character:
142  *		s	string
143  *		i	signed integer
144  *		u	unsigned integer
145  *		x	hex
146  *
147  * TODO: Implement ll modifier (8 bytes)
148  * TODO: Implement o type (octal)
149  *
150  * @param fmt		Format string to process
151  * @param type		Returns type found(s/d/u/x), or 0 if none
152  * @param size		Returns size found(1,2,4,8) or 4 if none
153  * @return 0 if ok, -1 on error (no type given, or other invalid format)
154  */
155 int utilfdt_decode_type(const char *fmt, int *type, int *size);
156 
157 /*
158  * This is a usage message fragment for the -t option. It is the format
159  * supported by utilfdt_decode_type.
160  */
161 
162 #define USAGE_TYPE_MSG \
163 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
164 	"\tOptional modifier prefix:\n" \
165 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
166 
167 /**
168  * Print property data in a readable format to stdout
169  *
170  * Properties that look like strings will be printed as strings. Otherwise
171  * the data will be displayed either as cells (if len is a multiple of 4
172  * bytes) or bytes.
173  *
174  * If len is 0 then this function does nothing.
175  *
176  * @param data	Pointers to property data
177  * @param len	Length of property data
178  */
179 void utilfdt_print_data(const char *data, int len);
180 
181 /**
182  * Show source version and exit
183  */
184 void NORETURN util_version(void);
185 
186 /**
187  * Show usage and exit
188  *
189  * This helps standardize the output of various utils.  You most likely want
190  * to use the usage() helper below rather than call this.
191  *
192  * @param errmsg	If non-NULL, an error message to display
193  * @param synopsis	The initial example usage text (and possible examples)
194  * @param short_opts	The string of short options
195  * @param long_opts	The structure of long options
196  * @param opts_help	An array of help strings (should align with long_opts)
197  */
198 void NORETURN util_usage(const char *errmsg, const char *synopsis,
199 			 const char *short_opts,
200 			 struct option const long_opts[],
201 			 const char * const opts_help[]);
202 
203 /**
204  * Show usage and exit
205  *
206  * If you name all your usage variables with usage_xxx, then you can call this
207  * help macro rather than expanding all arguments yourself.
208  *
209  * @param errmsg	If non-NULL, an error message to display
210  */
211 #define usage(errmsg) \
212 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
213 		   usage_long_opts, usage_opts_help)
214 
215 /**
216  * Call getopt_long() with standard options
217  *
218  * Since all util code runs getopt in the same way, provide a helper.
219  */
220 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
221 				       usage_long_opts, NULL)
222 
223 /* Helper for aligning long_opts array */
224 #define a_argument required_argument
225 
226 /* Helper for usage_short_opts string constant */
227 #define USAGE_COMMON_SHORT_OPTS "hV"
228 
229 /* Helper for usage_long_opts option array */
230 #define USAGE_COMMON_LONG_OPTS \
231 	{"help",      no_argument, NULL, 'h'}, \
232 	{"version",   no_argument, NULL, 'V'}, \
233 	{NULL,        no_argument, NULL, 0x0}
234 
235 /* Helper for usage_opts_help array */
236 #define USAGE_COMMON_OPTS_HELP \
237 	"Print this help and exit", \
238 	"Print version and exit", \
239 	NULL
240 
241 /* Helper for getopt case statements */
242 #define case_USAGE_COMMON_FLAGS \
243 	case 'h': usage(NULL); \
244 	case 'V': util_version(); \
245 	case '?': usage("unknown option");
246 
247 #endif /* UTIL_H */
248