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
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