Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
34static 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
45/**
46 * Writes path to fp, escaping spaces with a backslash.
47 */
48void fprint_path_escaped(FILE *fp, const char *path);
49
50static inline void *xmalloc(size_t len)
51{
52 void *new = malloc(len);
53
54 if (!new)
55 die("malloc() failed\n");
56
57 return new;
58}
59
60static inline void *xrealloc(void *p, size_t len)
61{
62 void *new = realloc(p, len);
63
64 if (!new)
65 die("realloc() failed (len=%zd)\n", len);
66
67 return new;
68}
69
70extern char *xstrdup(const char *s);
71extern char *xstrndup(const char *s, size_t len);
72
73extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
74extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
75extern int PRINTF(2, 0) xavsprintf_append(char **strp, const char *fmt, va_list ap);
76extern char *join_path(const char *path, const char *name);
77
78/**
79 * Check a property of a given length to see if it is all printable and
80 * has a valid terminator. The property can contain either a single string,
81 * or multiple strings each of non-zero length.
82 *
83 * @param data The string to check
84 * @param len The string length including terminator
85 * @return 1 if a valid printable string, 0 if not
86 */
87bool util_is_printable_string(const void *data, int len);
88
89/*
90 * Parse an escaped character starting at index i in string s. The resulting
91 * character will be returned and the index i will be updated to point at the
92 * character directly after the end of the encoding, this may be the '\0'
93 * terminator of the string.
94 */
95char get_escape_char(const char *s, int *i);
96
97/**
98 * Read a device tree file into a buffer. This will report any errors on
99 * stderr.
100 *
101 * @param filename The filename to read, or - for stdin
102 * @param len If non-NULL, the amount of data we managed to read
103 * @return Pointer to allocated buffer containing fdt, or NULL on error
104 */
105char *utilfdt_read(const char *filename, size_t *len);
106
107/**
108 * Read a device tree file into a buffer. Does not report errors, but only
109 * returns them. The value returned can be passed to strerror() to obtain
110 * an error message for the user.
111 *
112 * @param filename The filename to read, or - for stdin
113 * @param buffp Returns pointer to buffer containing fdt
114 * @param len If non-NULL, the amount of data we managed to read
115 * @return 0 if ok, else an errno value representing the error
116 */
117int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
118
119/**
120 * Write a device tree buffer to a file. This will report any errors on
121 * stderr.
122 *
123 * @param filename The filename to write, or - for stdout
124 * @param blob Pointer to buffer containing fdt
125 * @return 0 if ok, -1 on error
126 */
127int utilfdt_write(const char *filename, const void *blob);
128
129/**
130 * Write a device tree buffer to a file. Does not report errors, but only
131 * returns them. The value returned can be passed to strerror() to obtain
132 * an error message for the user.
133 *
134 * @param filename The filename to write, or - for stdout
135 * @param blob Pointer to buffer containing fdt
136 * @return 0 if ok, else an errno value representing the error
137 */
138int utilfdt_write_err(const char *filename, const void *blob);
139
140/**
141 * Decode a data type string. The purpose of this string
142 *
143 * The string consists of an optional character followed by the type:
144 * Modifier characters:
145 * hh or b 1 byte
146 * h 2 byte
147 * l 4 byte, default
148 *
149 * Type character:
150 * s string
151 * i signed integer
152 * u unsigned integer
153 * x hex
154 * r raw
155 *
156 * TODO: Implement ll modifier (8 bytes)
157 * TODO: Implement o type (octal)
158 *
159 * @param fmt Format string to process
160 * @param type Returns type found(s/d/u/x), or 0 if none
161 * @param size Returns size found(1,2,4,8) or 4 if none
162 * @return 0 if ok, -1 on error (no type given, or other invalid format)
163 */
164int utilfdt_decode_type(const char *fmt, int *type, int *size);
165
166/*
167 * This is a usage message fragment for the -t option. It is the format
168 * supported by utilfdt_decode_type.
169 */
170
171#define USAGE_TYPE_MSG \
172 "<type>\ts=string, i=int, u=unsigned, x=hex, r=raw\n" \
173 "\tOptional modifier prefix:\n" \
174 "\t\thh or b=byte, h=2 byte, l=4 byte (default)";
175
176/**
177 * Print property data in a readable format to stdout
178 *
179 * Properties that look like strings will be printed as strings. Otherwise
180 * the data will be displayed either as cells (if len is a multiple of 4
181 * bytes) or bytes.
182 *
183 * If len is 0 then this function does nothing.
184 *
185 * @param data Pointers to property data
186 * @param len Length of property data
187 */
188void utilfdt_print_data(const char *data, int len);
189
190/**
191 * Show source version and exit
192 */
193void NORETURN util_version(void);
194
195/**
196 * Show usage and exit
197 *
198 * This helps standardize the output of various utils. You most likely want
199 * to use the usage() helper below rather than call this.
200 *
201 * @param errmsg If non-NULL, an error message to display
202 * @param synopsis The initial example usage text (and possible examples)
203 * @param short_opts The string of short options
204 * @param long_opts The structure of long options
205 * @param opts_help An array of help strings (should align with long_opts)
206 */
207void NORETURN util_usage(const char *errmsg, const char *synopsis,
208 const char *short_opts,
209 struct option const long_opts[],
210 const char * const opts_help[]);
211
212/**
213 * Show usage and exit
214 *
215 * If you name all your usage variables with usage_xxx, then you can call this
216 * help macro rather than expanding all arguments yourself.
217 *
218 * @param errmsg If non-NULL, an error message to display
219 */
220#define usage(errmsg) \
221 util_usage(errmsg, usage_synopsis, usage_short_opts, \
222 usage_long_opts, usage_opts_help)
223
224/**
225 * Call getopt_long() with standard options
226 *
227 * Since all util code runs getopt in the same way, provide a helper.
228 */
229#define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
230 usage_long_opts, NULL)
231
232/* Helper for aligning long_opts array */
233#define a_argument required_argument
234
235/* Helper for usage_short_opts string constant */
236#define USAGE_COMMON_SHORT_OPTS "hV"
237
238/* Helper for usage_long_opts option array */
239#define USAGE_COMMON_LONG_OPTS \
240 {"help", no_argument, NULL, 'h'}, \
241 {"version", no_argument, NULL, 'V'}, \
242 {NULL, no_argument, NULL, 0x0}
243
244/* Helper for usage_opts_help array */
245#define USAGE_COMMON_OPTS_HELP \
246 "Print this help and exit", \
247 "Print version and exit", \
248 NULL
249
250/* Helper for getopt case statements */
251#define case_USAGE_COMMON_FLAGS \
252 case 'h': usage(NULL); \
253 case 'V': util_version(); \
254 case '?': usage("unknown option");
255
256#endif /* UTIL_H */