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
die(const char * str,...)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
xmalloc(size_t len)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
xrealloc(void * p,size_t len)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