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