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 __MINGW_PRINTF_FORMAT
17 #define PRINTF(i, j) __attribute__((format (__MINGW_PRINTF_FORMAT, i, j)))
18 #elif __GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4)
19 #define PRINTF(i, j) __attribute__((format (gnu_printf, i, j)))
20 #else
21 #define PRINTF(i, j) __attribute__((format (printf, i, j)))
22 #endif
23 #define NORETURN __attribute__((noreturn))
24 #else
25 #define PRINTF(i, j)
26 #define NORETURN
27 #endif
28
29 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
30
31 #define stringify(s) stringify_(s)
32 #define stringify_(s) #s
33
die(const char * str,...)34 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
35 {
36 va_list ap;
37
38 va_start(ap, str);
39 fprintf(stderr, "FATAL ERROR: ");
40 vfprintf(stderr, str, ap);
41 va_end(ap);
42 exit(1);
43 }
44
xmalloc(size_t len)45 static inline void *xmalloc(size_t len)
46 {
47 void *new = malloc(len);
48
49 if (!new)
50 die("malloc() failed\n");
51
52 return new;
53 }
54
xrealloc(void * p,size_t len)55 static inline void *xrealloc(void *p, size_t len)
56 {
57 void *new = realloc(p, len);
58
59 if (!new)
60 die("realloc() failed (len=%zd)\n", len);
61
62 return new;
63 }
64
65 extern char *xstrdup(const char *s);
66 extern char *xstrndup(const char *s, size_t len);
67
68 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
69 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
70 extern int PRINTF(2, 0) xavsprintf_append(char **strp, const char *fmt, va_list ap);
71 extern char *join_path(const char *path, const char *name);
72
73 /**
74 * Check a property of a given length to see if it is all printable and
75 * has a valid terminator. The property can contain either a single string,
76 * or multiple strings each of non-zero length.
77 *
78 * @param data The string to check
79 * @param len The string length including terminator
80 * @return 1 if a valid printable string, 0 if not
81 */
82 bool util_is_printable_string(const void *data, int len);
83
84 /*
85 * Parse an escaped character starting at index i in string s. The resulting
86 * character will be returned and the index i will be updated to point at the
87 * character directly after the end of the encoding, this may be the '\0'
88 * terminator of the string.
89 */
90 char get_escape_char(const char *s, int *i);
91
92 /**
93 * Read a device tree file into a buffer. This will report any errors on
94 * stderr.
95 *
96 * @param filename The filename to read, or - for stdin
97 * @param len If non-NULL, the amount of data we managed to read
98 * @return Pointer to allocated buffer containing fdt, or NULL on error
99 */
100 char *utilfdt_read(const char *filename, size_t *len);
101
102 /**
103 * Read a device tree file into a buffer. Does not report errors, but only
104 * returns them. The value returned can be passed to strerror() to obtain
105 * an error message for the user.
106 *
107 * @param filename The filename to read, or - for stdin
108 * @param buffp Returns pointer to buffer containing fdt
109 * @param len If non-NULL, the amount of data we managed to read
110 * @return 0 if ok, else an errno value representing the error
111 */
112 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
113
114 /**
115 * Write a device tree buffer to a file. This will report any errors on
116 * stderr.
117 *
118 * @param filename The filename to write, or - for stdout
119 * @param blob Pointer to buffer containing fdt
120 * @return 0 if ok, -1 on error
121 */
122 int utilfdt_write(const char *filename, const void *blob);
123
124 /**
125 * Write a device tree buffer to a file. Does not report errors, but only
126 * returns them. The value returned can be passed to strerror() to obtain
127 * an error message for the user.
128 *
129 * @param filename The filename to write, or - for stdout
130 * @param blob Pointer to buffer containing fdt
131 * @return 0 if ok, else an errno value representing the error
132 */
133 int utilfdt_write_err(const char *filename, const void *blob);
134
135 /**
136 * Decode a data type string. The purpose of this string
137 *
138 * The string consists of an optional character followed by the type:
139 * Modifier characters:
140 * hh or b 1 byte
141 * h 2 byte
142 * l 4 byte, default
143 *
144 * Type character:
145 * s string
146 * i signed integer
147 * u unsigned integer
148 * x hex
149 * r raw
150 *
151 * TODO: Implement ll modifier (8 bytes)
152 * TODO: Implement o type (octal)
153 *
154 * @param fmt Format string to process
155 * @param type Returns type found(s/d/u/x), or 0 if none
156 * @param size Returns size found(1,2,4,8) or 4 if none
157 * @return 0 if ok, -1 on error (no type given, or other invalid format)
158 */
159 int utilfdt_decode_type(const char *fmt, int *type, int *size);
160
161 /*
162 * This is a usage message fragment for the -t option. It is the format
163 * supported by utilfdt_decode_type.
164 */
165
166 #define USAGE_TYPE_MSG \
167 "<type>\ts=string, i=int, u=unsigned, x=hex, r=raw\n" \
168 "\tOptional modifier prefix:\n" \
169 "\t\thh or b=byte, h=2 byte, l=4 byte (default)";
170
171 /**
172 * Print property data in a readable format to stdout
173 *
174 * Properties that look like strings will be printed as strings. Otherwise
175 * the data will be displayed either as cells (if len is a multiple of 4
176 * bytes) or bytes.
177 *
178 * If len is 0 then this function does nothing.
179 *
180 * @param data Pointers to property data
181 * @param len Length of property data
182 */
183 void utilfdt_print_data(const char *data, int len);
184
185 /**
186 * Show source version and exit
187 */
188 void NORETURN util_version(void);
189
190 /**
191 * Show usage and exit
192 *
193 * This helps standardize the output of various utils. You most likely want
194 * to use the usage() helper below rather than call this.
195 *
196 * @param errmsg If non-NULL, an error message to display
197 * @param synopsis The initial example usage text (and possible examples)
198 * @param short_opts The string of short options
199 * @param long_opts The structure of long options
200 * @param opts_help An array of help strings (should align with long_opts)
201 */
202 void NORETURN util_usage(const char *errmsg, const char *synopsis,
203 const char *short_opts,
204 struct option const long_opts[],
205 const char * const opts_help[]);
206
207 /**
208 * Show usage and exit
209 *
210 * If you name all your usage variables with usage_xxx, then you can call this
211 * help macro rather than expanding all arguments yourself.
212 *
213 * @param errmsg If non-NULL, an error message to display
214 */
215 #define usage(errmsg) \
216 util_usage(errmsg, usage_synopsis, usage_short_opts, \
217 usage_long_opts, usage_opts_help)
218
219 /**
220 * Call getopt_long() with standard options
221 *
222 * Since all util code runs getopt in the same way, provide a helper.
223 */
224 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
225 usage_long_opts, NULL)
226
227 /* Helper for aligning long_opts array */
228 #define a_argument required_argument
229
230 /* Helper for usage_short_opts string constant */
231 #define USAGE_COMMON_SHORT_OPTS "hV"
232
233 /* Helper for usage_long_opts option array */
234 #define USAGE_COMMON_LONG_OPTS \
235 {"help", no_argument, NULL, 'h'}, \
236 {"version", no_argument, NULL, 'V'}, \
237 {NULL, no_argument, NULL, 0x0}
238
239 /* Helper for usage_opts_help array */
240 #define USAGE_COMMON_OPTS_HELP \
241 "Print this help and exit", \
242 "Print version and exit", \
243 NULL
244
245 /* Helper for getopt case statements */
246 #define case_USAGE_COMMON_FLAGS \
247 case 'h': usage(NULL); \
248 case 'V': util_version(); \
249 case '?': usage("unknown option");
250
251 #endif /* UTIL_H */
252