scripts/dtc/util.h

   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 static inline void __attribute__((noreturn)) die(const char *str, ...)
  31 {
  32         va_list ap;
  33
  34         va_start(ap, str);
  35         fprintf(stderr, "FATAL ERROR: ");
  36         vfprintf(stderr, str, ap);
  37         va_end(ap);
  38         exit(1);
  39 }
  40
  41 static inline void *xmalloc(size_t len)
  42 {
  43         void *new = malloc(len);
  44
  45         if (!new)
  46                 die("malloc() failed\n");
  47
  48         return new;
  49 }
  50
  51 static inline void *xrealloc(void *p, size_t len)
  52 {
  53         void *new = realloc(p, len);
  54
  55         if (!new)
  56                 die("realloc() failed (len=%d)\n", len);
  57
  58         return new;
  59 }
  60
  61 extern char *xstrdup(const char *s);
  62 extern int xasprintf(char **strp, const char *fmt, ...);
  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  * @return Pointer to allocated buffer containing fdt, or NULL on error
  90  */
  91 char *utilfdt_read(const char *filename);
  92
  93 /**
  94  * Like utilfdt_read(), but also passes back the size of the file read.
  95  *
  96  * @param len           If non-NULL, the amount of data we managed to read
  97  */
  98 char *utilfdt_read_len(const char *filename, off_t *len);
  99
 100 /**
 101  * Read a device tree file into a buffer. Does not report errors, but only
 102  * returns them. The value returned can be passed to strerror() to obtain
 103  * an error message for the user.
 104  *
 105  * @param filename      The filename to read, or - for stdin
 106  * @param buffp         Returns pointer to buffer containing fdt
 107  * @return 0 if ok, else an errno value representing the error
 108  */
 109 int utilfdt_read_err(const char *filename, char **buffp);
 110
 111 /**
 112  * Like utilfdt_read_err(), but also passes back the size of the file read.
 113  *
 114  * @param len           If non-NULL, the amount of data we managed to read
 115  */
 116 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
 117
 118 /**
 119  * Write a device tree buffer to a file. This will report any errors on
 120  * stderr.
 121  *
 122  * @param filename      The filename to write, or - for stdout
 123  * @param blob          Poiner to buffer containing fdt
 124  * @return 0 if ok, -1 on error
 125  */
 126 int utilfdt_write(const char *filename, const void *blob);
 127
 128 /**
 129  * Write a device tree buffer to a file. Does not report errors, but only
 130  * returns them. The value returned can be passed to strerror() to obtain
 131  * an error message for the user.
 132  *
 133  * @param filename      The filename to write, or - for stdout
 134  * @param blob          Poiner to buffer containing fdt
 135  * @return 0 if ok, else an errno value representing the error
 136  */
 137 int utilfdt_write_err(const char *filename, const void *blob);
 138
 139 /**
 140  * Decode a data type string. The purpose of this string
 141  *
 142  * The string consists of an optional character followed by the type:
 143  *      Modifier characters:
 144  *              hh or b 1 byte
 145  *              h       2 byte
 146  *              l       4 byte, default
 147  *
 148  *      Type character:
 149  *              s       string
 150  *              i       signed integer
 151  *              u       unsigned integer
 152  *              x       hex
 153  *
 154  * TODO: Implement ll modifier (8 bytes)
 155  * TODO: Implement o type (octal)
 156  *
 157  * @param fmt           Format string to process
 158  * @param type          Returns type found(s/d/u/x), or 0 if none
 159  * @param size          Returns size found(1,2,4,8) or 4 if none
 160  * @return 0 if ok, -1 on error (no type given, or other invalid format)
 161  */
 162 int utilfdt_decode_type(const char *fmt, int *type, int *size);
 163
 164 /*
 165  * This is a usage message fragment for the -t option. It is the format
 166  * supported by utilfdt_decode_type.
 167  */
 168
 169 #define USAGE_TYPE_MSG \
 170         "<type>\ts=string, i=int, u=unsigned, x=hex\n" \
 171         "\tOptional modifier prefix:\n" \
 172         "\t\thh or b=byte, h=2 byte, l=4 byte (default)";
 173
 174 /**
 175  * Print property data in a readable format to stdout
 176  *
 177  * Properties that look like strings will be printed as strings. Otherwise
 178  * the data will be displayed either as cells (if len is a multiple of 4
 179  * bytes) or bytes.
 180  *
 181  * If len is 0 then this function does nothing.
 182  *
 183  * @param data  Pointers to property data
 184  * @param len   Length of property data
 185  */
 186 void utilfdt_print_data(const char *data, int len);
 187
 188 /**
 189  * Show source version and exit
 190  */
 191 void util_version(void) __attribute__((noreturn));
 192
 193 /**
 194  * Show usage and exit
 195  *
 196  * This helps standardize the output of various utils.  You most likely want
 197  * to use the usage() helper below rather than call this.
 198  *
 199  * @param errmsg        If non-NULL, an error message to display
 200  * @param synopsis      The initial example usage text (and possible examples)
 201  * @param short_opts    The string of short options
 202  * @param long_opts     The structure of long options
 203  * @param opts_help     An array of help strings (should align with long_opts)
 204  */
 205 void util_usage(const char *errmsg, const char *synopsis,
 206                 const char *short_opts, struct option const long_opts[],
 207                 const char * const opts_help[]) __attribute__((noreturn));
 208
 209 /**
 210  * Show usage and exit
 211  *
 212  * If you name all your usage variables with usage_xxx, then you can call this
 213  * help macro rather than expanding all arguments yourself.
 214  *
 215  * @param errmsg        If non-NULL, an error message to display
 216  */
 217 #define usage(errmsg) \
 218         util_usage(errmsg, usage_synopsis, usage_short_opts, \
 219                    usage_long_opts, usage_opts_help)
 220
 221 /**
 222  * Call getopt_long() with standard options
 223  *
 224  * Since all util code runs getopt in the same way, provide a helper.
 225  */
 226 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
 227                                        usage_long_opts, NULL)
 228
 229 /* Helper for aligning long_opts array */
 230 #define a_argument required_argument
 231
 232 /* Helper for usage_short_opts string constant */
 233 #define USAGE_COMMON_SHORT_OPTS "hV"
 234
 235 /* Helper for usage_long_opts option array */
 236 #define USAGE_COMMON_LONG_OPTS \
 237         {"help",      no_argument, NULL, 'h'}, \
 238         {"version",   no_argument, NULL, 'V'}, \
 239         {NULL,        no_argument, NULL, 0x0}
 240
 241 /* Helper for usage_opts_help array */
 242 #define USAGE_COMMON_OPTS_HELP \
 243         "Print this help and exit", \
 244         "Print version and exit", \
 245         NULL
 246
 247 /* Helper for getopt case statements */
 248 #define case_USAGE_COMMON_FLAGS \
 249         case 'h': usage(NULL); \
 250         case 'V': util_version(); \
 251         case '?': usage("unknown option");
 252
 253 #endif /* _UTIL_H */