util.h revision 318102
1#ifndef _UTIL_H 2#define _UTIL_H 3 4#include <stdarg.h> 5#include <stdbool.h> 6#include <getopt.h> 7 8/* 9 * Copyright 2011 The Chromium Authors, All Rights Reserved. 10 * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc. 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License as 14 * published by the Free Software Foundation; either version 2 of the 15 * License, or (at your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License 23 * along with this program; if not, write to the Free Software 24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 25 * USA 26 */ 27 28#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) 29 30#ifdef __GNUC__ 31static inline void 32__attribute__((noreturn)) __attribute__((format (printf, 1, 2))) 33die(const char *str, ...) 34#else 35static inline void die(const char *str, ...) 36#endif 37{ 38 va_list ap; 39 40 va_start(ap, str); 41 fprintf(stderr, "FATAL ERROR: "); 42 vfprintf(stderr, str, ap); 43 va_end(ap); 44 exit(1); 45} 46 47static inline void *xmalloc(size_t len) 48{ 49 void *new = malloc(len); 50 51 if (!new) 52 die("malloc() failed\n"); 53 54 return new; 55} 56 57static inline void *xrealloc(void *p, size_t len) 58{ 59 void *new = realloc(p, len); 60 61 if (!new) 62 die("realloc() failed (len=%zd)\n", len); 63 64 return new; 65} 66 67extern char *xstrdup(const char *s); 68 69#ifdef __GNUC__ 70extern int __attribute__((format (printf, 2, 3))) 71xasprintf(char **strp, const char *fmt, ...); 72#else 73extern int xasprintf(char **strp, const char *fmt, ...); 74#endif 75extern char *join_path(const char *path, const char *name); 76 77/** 78 * Check a property of a given length to see if it is all printable and 79 * has a valid terminator. The property can contain either a single string, 80 * or multiple strings each of non-zero length. 81 * 82 * @param data The string to check 83 * @param len The string length including terminator 84 * @return 1 if a valid printable string, 0 if not 85 */ 86bool util_is_printable_string(const void *data, int len); 87 88/* 89 * Parse an escaped character starting at index i in string s. The resulting 90 * character will be returned and the index i will be updated to point at the 91 * character directly after the end of the encoding, this may be the '\0' 92 * terminator of the string. 93 */ 94char get_escape_char(const char *s, int *i); 95 96/** 97 * Read a device tree file into a buffer. This will report any errors on 98 * stderr. 99 * 100 * @param filename The filename to read, or - for stdin 101 * @return Pointer to allocated buffer containing fdt, or NULL on error 102 */ 103char *utilfdt_read(const char *filename); 104 105/** 106 * Like utilfdt_read(), but also passes back the size of the file read. 107 * 108 * @param len If non-NULL, the amount of data we managed to read 109 */ 110char *utilfdt_read_len(const char *filename, off_t *len); 111 112/** 113 * Read a device tree file into a buffer. Does not report errors, but only 114 * returns them. The value returned can be passed to strerror() to obtain 115 * an error message for the user. 116 * 117 * @param filename The filename to read, or - for stdin 118 * @param buffp Returns pointer to buffer containing fdt 119 * @return 0 if ok, else an errno value representing the error 120 */ 121int utilfdt_read_err(const char *filename, char **buffp); 122 123/** 124 * Like utilfdt_read_err(), but also passes back the size of the file read. 125 * 126 * @param len If non-NULL, the amount of data we managed to read 127 */ 128int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len); 129 130/** 131 * Write a device tree buffer to a file. This will report any errors on 132 * stderr. 133 * 134 * @param filename The filename to write, or - for stdout 135 * @param blob Poiner to buffer containing fdt 136 * @return 0 if ok, -1 on error 137 */ 138int utilfdt_write(const char *filename, const void *blob); 139 140/** 141 * Write a device tree buffer to a file. Does not report errors, but only 142 * returns them. The value returned can be passed to strerror() to obtain 143 * an error message for the user. 144 * 145 * @param filename The filename to write, or - for stdout 146 * @param blob Poiner to buffer containing fdt 147 * @return 0 if ok, else an errno value representing the error 148 */ 149int utilfdt_write_err(const char *filename, const void *blob); 150 151/** 152 * Decode a data type string. The purpose of this string 153 * 154 * The string consists of an optional character followed by the type: 155 * Modifier characters: 156 * hh or b 1 byte 157 * h 2 byte 158 * l 4 byte, default 159 * 160 * Type character: 161 * s string 162 * i signed integer 163 * u unsigned integer 164 * x hex 165 * 166 * TODO: Implement ll modifier (8 bytes) 167 * TODO: Implement o type (octal) 168 * 169 * @param fmt Format string to process 170 * @param type Returns type found(s/d/u/x), or 0 if none 171 * @param size Returns size found(1,2,4,8) or 4 if none 172 * @return 0 if ok, -1 on error (no type given, or other invalid format) 173 */ 174int utilfdt_decode_type(const char *fmt, int *type, int *size); 175 176/* 177 * This is a usage message fragment for the -t option. It is the format 178 * supported by utilfdt_decode_type. 179 */ 180 181#define USAGE_TYPE_MSG \ 182 "<type>\ts=string, i=int, u=unsigned, x=hex\n" \ 183 "\tOptional modifier prefix:\n" \ 184 "\t\thh or b=byte, h=2 byte, l=4 byte (default)"; 185 186/** 187 * Print property data in a readable format to stdout 188 * 189 * Properties that look like strings will be printed as strings. Otherwise 190 * the data will be displayed either as cells (if len is a multiple of 4 191 * bytes) or bytes. 192 * 193 * If len is 0 then this function does nothing. 194 * 195 * @param data Pointers to property data 196 * @param len Length of property data 197 */ 198void utilfdt_print_data(const char *data, int len); 199 200/** 201 * Show source version and exit 202 */ 203void util_version(void) __attribute__((noreturn)); 204 205/** 206 * Show usage and exit 207 * 208 * This helps standardize the output of various utils. You most likely want 209 * to use the usage() helper below rather than call this. 210 * 211 * @param errmsg If non-NULL, an error message to display 212 * @param synopsis The initial example usage text (and possible examples) 213 * @param short_opts The string of short options 214 * @param long_opts The structure of long options 215 * @param opts_help An array of help strings (should align with long_opts) 216 */ 217void util_usage(const char *errmsg, const char *synopsis, 218 const char *short_opts, struct option const long_opts[], 219 const char * const opts_help[]) __attribute__((noreturn)); 220 221/** 222 * Show usage and exit 223 * 224 * If you name all your usage variables with usage_xxx, then you can call this 225 * help macro rather than expanding all arguments yourself. 226 * 227 * @param errmsg If non-NULL, an error message to display 228 */ 229#define usage(errmsg) \ 230 util_usage(errmsg, usage_synopsis, usage_short_opts, \ 231 usage_long_opts, usage_opts_help) 232 233/** 234 * Call getopt_long() with standard options 235 * 236 * Since all util code runs getopt in the same way, provide a helper. 237 */ 238#define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \ 239 usage_long_opts, NULL) 240 241/* Helper for aligning long_opts array */ 242#define a_argument required_argument 243 244/* Helper for usage_short_opts string constant */ 245#define USAGE_COMMON_SHORT_OPTS "hV" 246 247/* Helper for usage_long_opts option array */ 248#define USAGE_COMMON_LONG_OPTS \ 249 {"help", no_argument, NULL, 'h'}, \ 250 {"version", no_argument, NULL, 'V'}, \ 251 {NULL, no_argument, NULL, 0x0} 252 253/* Helper for usage_opts_help array */ 254#define USAGE_COMMON_OPTS_HELP \ 255 "Print this help and exit", \ 256 "Print version and exit", \ 257 NULL 258 259/* Helper for getopt case statements */ 260#define case_USAGE_COMMON_FLAGS \ 261 case 'h': usage(NULL); \ 262 case 'V': util_version(); \ 263 case '?': usage("unknown option"); 264 265#endif /* _UTIL_H */ 266