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