scripts/dtc/util.h

   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 #ifdef __clang__
  16 #define PRINTF(i, j)    __attribute__((format (printf, i, j)))
  17 #else
  18 #define PRINTF(i, j)    __attribute__((format (gnu_printf, i, j)))
  19 #endif
  20 #define NORETURN        __attribute__((noreturn))
  21 #else
  22 #define PRINTF(i, j)
  23 #define NORETURN
  24 #endif
  25
  26 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  27
  28 #define stringify(s)    stringify_(s)
  29 #define stringify_(s)   #s
  30
  31 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
  32 {
  33         va_list ap;
  34
  35         va_start(ap, str);
  36         fprintf(stderr, "FATAL ERROR: ");
  37         vfprintf(stderr, str, ap);
  38         va_end(ap);
  39         exit(1);
  40 }
  41
  42 static inline void *xmalloc(size_t len)
  43 {
  44         void *new = malloc(len);
  45
  46         if (!new)
  47                 die("malloc() failed\n");
  48
  49         return new;
  50 }
  51
  52 static inline void *xrealloc(void *p, size_t len)
  53 {
  54         void *new = realloc(p, len);
  55
  56         if (!new)
  57                 die("realloc() failed (len=%zd)\n", len);
  58
  59         return new;
  60 }
  61
  62 extern char *xstrdup(const char *s);
  63
  64 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
  65 extern int PRINTF(2, 3) xasprintf_append(char **strp, const char *fmt, ...);
  66 extern int xavsprintf_append(char **strp, const char *fmt, va_list ap);
  67 extern char *join_path(const char *path, const char *name);
  68
  69 /**
  70  * Check a property of a given length to see if it is all printable and
  71  * has a valid terminator. The property can contain either a single string,
  72  * or multiple strings each of non-zero length.
  73  *
  74  * @param data  The string to check
  75  * @param len   The string length including terminator
  76  * @return 1 if a valid printable string, 0 if not
  77  */
  78 bool util_is_printable_string(const void *data, int len);
  79
  80 /*
  81  * Parse an escaped character starting at index i in string s.  The resulting
  82  * character will be returned and the index i will be updated to point at the
  83  * character directly after the end of the encoding, this may be the '\0'
  84  * terminator of the string.
  85  */
  86 char get_escape_char(const char *s, int *i);
  87
  88 /**
  89  * Read a device tree file into a buffer. This will report any errors on
  90  * stderr.
  91  *
  92  * @param filename      The filename to read, or - for stdin
  93  * @param len           If non-NULL, the amount of data we managed to read
  94  * @return Pointer to allocated buffer containing fdt, or NULL on error
  95  */
  96 char *utilfdt_read(const char *filename, size_t *len);
  97
  98 /**
  99  * Read a device tree file into a buffer. Does not report errors, but only
 100  * returns them. The value returned can be passed to strerror() to obtain
 101  * an error message for the user.
 102  *
 103  * @param filename      The filename to read, or - for stdin
 104  * @param buffp         Returns pointer to buffer containing fdt
 105  * @param len           If non-NULL, the amount of data we managed to read
 106  * @return 0 if ok, else an errno value representing the error
 107  */
 108 int utilfdt_read_err(const char *filename, char **buffp, size_t *len);
 109
 110 /**
 111  * Write a device tree buffer to a file. This will report any errors on
 112  * stderr.
 113  *
 114  * @param filename      The filename to write, or - for stdout
 115  * @param blob          Pointer to buffer containing fdt
 116  * @return 0 if ok, -1 on error
 117  */
 118 int utilfdt_write(const char *filename, const void *blob);
 119
 120 /**
 121  * Write a device tree buffer to a file. Does not report errors, but only
 122  * returns them. The value returned can be passed to strerror() to obtain
 123  * an error message for the user.
 124  *
 125  * @param filename      The filename to write, or - for stdout
 126  * @param blob          Pointer to buffer containing fdt
 127  * @return 0 if ok, else an errno value representing the error
 128  */
 129 int utilfdt_write_err(const char *filename, const void *blob);
 130
 131 /**
 132  * Decode a data type string. The purpose of this string
 133  *
 134  * The string consists of an optional character followed by the type:
 135  *      Modifier characters:
 136  *              hh or b 1 byte
 137  *              h       2 byte
 138  *              l       4 byte, default
 139  *
 140  *      Type character:
 141  *              s       string
 142  *              i       signed integer
 143  *              u       unsigned integer
 144  *              x       hex
 145  *
 146  * TODO: Implement ll modifier (8 bytes)
 147  * TODO: Implement o type (octal)
 148  *
 149  * @param fmt           Format string to process
 150  * @param type          Returns type found(s/d/u/x), or 0 if none
 151  * @param size          Returns size found(1,2,4,8) or 4 if none
 152  * @return 0 if ok, -1 on error (no type given, or other invalid format)
 153  */
 154 int utilfdt_decode_type(const char *fmt, int *type, int *size);
 155
 156 /*
 157  * This is a usage message fragment for the -t option. It is the format
 158  * supported by utilfdt_decode_type.
 159  */
 160
 161 #define USAGE_TYPE_MSG \
 162         "<type>\ts=string, i=int, u=unsigned, x=hex\n" \
 163         "\tOptional modifier prefix:\n" \
 164         "\t\thh or b=byte, h=2 byte, l=4 byte (default)";
 165
 166 /**
 167  * Print property data in a readable format to stdout
 168  *
 169  * Properties that look like strings will be printed as strings. Otherwise
 170  * the data will be displayed either as cells (if len is a multiple of 4
 171  * bytes) or bytes.
 172  *
 173  * If len is 0 then this function does nothing.
 174  *
 175  * @param data  Pointers to property data
 176  * @param len   Length of property data
 177  */
 178 void utilfdt_print_data(const char *data, int len);
 179
 180 /**
 181  * Show source version and exit
 182  */
 183 void NORETURN util_version(void);
 184
 185 /**
 186  * Show usage and exit
 187  *
 188  * This helps standardize the output of various utils.  You most likely want
 189  * to use the usage() helper below rather than call this.
 190  *
 191  * @param errmsg        If non-NULL, an error message to display
 192  * @param synopsis      The initial example usage text (and possible examples)
 193  * @param short_opts    The string of short options
 194  * @param long_opts     The structure of long options
 195  * @param opts_help     An array of help strings (should align with long_opts)
 196  */
 197 void NORETURN util_usage(const char *errmsg, const char *synopsis,
 198                          const char *short_opts,
 199                          struct option const long_opts[],
 200                          const char * const opts_help[]);
 201
 202 /**
 203  * Show usage and exit
 204  *
 205  * If you name all your usage variables with usage_xxx, then you can call this
 206  * help macro rather than expanding all arguments yourself.
 207  *
 208  * @param errmsg        If non-NULL, an error message to display
 209  */
 210 #define usage(errmsg) \
 211         util_usage(errmsg, usage_synopsis, usage_short_opts, \
 212                    usage_long_opts, usage_opts_help)
 213
 214 /**
 215  * Call getopt_long() with standard options
 216  *
 217  * Since all util code runs getopt in the same way, provide a helper.
 218  */
 219 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
 220                                        usage_long_opts, NULL)
 221
 222 /* Helper for aligning long_opts array */
 223 #define a_argument required_argument
 224
 225 /* Helper for usage_short_opts string constant */
 226 #define USAGE_COMMON_SHORT_OPTS "hV"
 227
 228 /* Helper for usage_long_opts option array */
 229 #define USAGE_COMMON_LONG_OPTS \
 230         {"help",      no_argument, NULL, 'h'}, \
 231         {"version",   no_argument, NULL, 'V'}, \
 232         {NULL,        no_argument, NULL, 0x0}
 233
 234 /* Helper for usage_opts_help array */
 235 #define USAGE_COMMON_OPTS_HELP \
 236         "Print this help and exit", \
 237         "Print version and exit", \
 238         NULL
 239
 240 /* Helper for getopt case statements */
 241 #define case_USAGE_COMMON_FLAGS \
 242         case 'h': usage(NULL); \
 243         case 'V': util_version(); \
 244         case '?': usage("unknown option");
 245
 246 #endif /* UTIL_H */