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