util.h (7175B)
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 32static 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 43static 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 53static 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 63extern char *xstrdup(const char *s); 64 65extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...); 66extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...); 67extern int xavsprintf_append(char **strp, const char *fmt, va_list ap); 68extern char *join_path(const char *path, const char *name); 69 70/** 71 * Check a property of a given length to see if it is all printable and 72 * has a valid terminator. The property can contain either a single string, 73 * or multiple strings each of non-zero length. 74 * 75 * @param data The string to check 76 * @param len The string length including terminator 77 * @return 1 if a valid printable string, 0 if not 78 */ 79bool util_is_printable_string(const void *data, int len); 80 81/* 82 * Parse an escaped character starting at index i in string s. The resulting 83 * character will be returned and the index i will be updated to point at the 84 * character directly after the end of the encoding, this may be the '\0' 85 * terminator of the string. 86 */ 87char get_escape_char(const char *s, int *i); 88 89/** 90 * Read a device tree file into a buffer. This will report any errors on 91 * stderr. 92 * 93 * @param filename The filename to read, or - for stdin 94 * @param len If non-NULL, the amount of data we managed to read 95 * @return Pointer to allocated buffer containing fdt, or NULL on error 96 */ 97char *utilfdt_read(const char *filename, size_t *len); 98 99/** 100 * Read a device tree file into a buffer. Does not report errors, but only 101 * returns them. The value returned can be passed to strerror() to obtain 102 * an error message for the user. 103 * 104 * @param filename The filename to read, or - for stdin 105 * @param buffp Returns pointer to buffer containing fdt 106 * @param len If non-NULL, the amount of data we managed to read 107 * @return 0 if ok, else an errno value representing the error 108 */ 109int utilfdt_read_err(const char *filename, char **buffp, size_t *len); 110 111/** 112 * Write a device tree buffer to a file. This will report any errors on 113 * stderr. 114 * 115 * @param filename The filename to write, or - for stdout 116 * @param blob Pointer to buffer containing fdt 117 * @return 0 if ok, -1 on error 118 */ 119int utilfdt_write(const char *filename, const void *blob); 120 121/** 122 * Write a device tree buffer to a file. Does not report errors, but only 123 * returns them. The value returned can be passed to strerror() to obtain 124 * an error message for the user. 125 * 126 * @param filename The filename to write, or - for stdout 127 * @param blob Pointer to buffer containing fdt 128 * @return 0 if ok, else an errno value representing the error 129 */ 130int utilfdt_write_err(const char *filename, const void *blob); 131 132/** 133 * Decode a data type string. The purpose of this string 134 * 135 * The string consists of an optional character followed by the type: 136 * Modifier characters: 137 * hh or b 1 byte 138 * h 2 byte 139 * l 4 byte, default 140 * 141 * Type character: 142 * s string 143 * i signed integer 144 * u unsigned integer 145 * x hex 146 * 147 * TODO: Implement ll modifier (8 bytes) 148 * TODO: Implement o type (octal) 149 * 150 * @param fmt Format string to process 151 * @param type Returns type found(s/d/u/x), or 0 if none 152 * @param size Returns size found(1,2,4,8) or 4 if none 153 * @return 0 if ok, -1 on error (no type given, or other invalid format) 154 */ 155int utilfdt_decode_type(const char *fmt, int *type, int *size); 156 157/* 158 * This is a usage message fragment for the -t option. It is the format 159 * supported by utilfdt_decode_type. 160 */ 161 162#define USAGE_TYPE_MSG \ 163 "<type>\ts=string, i=int, u=unsigned, x=hex\n" \ 164 "\tOptional modifier prefix:\n" \ 165 "\t\thh or b=byte, h=2 byte, l=4 byte (default)"; 166 167/** 168 * Print property data in a readable format to stdout 169 * 170 * Properties that look like strings will be printed as strings. Otherwise 171 * the data will be displayed either as cells (if len is a multiple of 4 172 * bytes) or bytes. 173 * 174 * If len is 0 then this function does nothing. 175 * 176 * @param data Pointers to property data 177 * @param len Length of property data 178 */ 179void utilfdt_print_data(const char *data, int len); 180 181/** 182 * Show source version and exit 183 */ 184void NORETURN util_version(void); 185 186/** 187 * Show usage and exit 188 * 189 * This helps standardize the output of various utils. You most likely want 190 * to use the usage() helper below rather than call this. 191 * 192 * @param errmsg If non-NULL, an error message to display 193 * @param synopsis The initial example usage text (and possible examples) 194 * @param short_opts The string of short options 195 * @param long_opts The structure of long options 196 * @param opts_help An array of help strings (should align with long_opts) 197 */ 198void NORETURN util_usage(const char *errmsg, const char *synopsis, 199 const char *short_opts, 200 struct option const long_opts[], 201 const char * const opts_help[]); 202 203/** 204 * Show usage and exit 205 * 206 * If you name all your usage variables with usage_xxx, then you can call this 207 * help macro rather than expanding all arguments yourself. 208 * 209 * @param errmsg If non-NULL, an error message to display 210 */ 211#define usage(errmsg) \ 212 util_usage(errmsg, usage_synopsis, usage_short_opts, \ 213 usage_long_opts, usage_opts_help) 214 215/** 216 * Call getopt_long() with standard options 217 * 218 * Since all util code runs getopt in the same way, provide a helper. 219 */ 220#define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \ 221 usage_long_opts, NULL) 222 223/* Helper for aligning long_opts array */ 224#define a_argument required_argument 225 226/* Helper for usage_short_opts string constant */ 227#define USAGE_COMMON_SHORT_OPTS "hV" 228 229/* Helper for usage_long_opts option array */ 230#define USAGE_COMMON_LONG_OPTS \ 231 {"help", no_argument, NULL, 'h'}, \ 232 {"version", no_argument, NULL, 'V'}, \ 233 {NULL, no_argument, NULL, 0x0} 234 235/* Helper for usage_opts_help array */ 236#define USAGE_COMMON_OPTS_HELP \ 237 "Print this help and exit", \ 238 "Print version and exit", \ 239 NULL 240 241/* Helper for getopt case statements */ 242#define case_USAGE_COMMON_FLAGS \ 243 case 'h': usage(NULL); \ 244 case 'V': util_version(); \ 245 case '?': usage("unknown option"); 246 247#endif /* UTIL_H */