scripts/dtc/util.h

   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
  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
  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
  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 */