release/src-rt-6.x.4708/tools/misc/xz/src/xz/util.c

   1 ///////////////////////////////////////////////////////////////////////////////
   2 //
   3 /// \file       util.c
   4 /// \brief      Miscellaneous utility functions
   5 //
   6 //  Author:     Lasse Collin
   7 //
   8 //  This file has been put into the public domain.
   9 //  You can do whatever you want with this file.
  10 //
  11 ///////////////////////////////////////////////////////////////////////////////
  12
  13 #include "private.h"
  14 #include <stdarg.h>
  15
  16
  17 /// Buffers for uint64_to_str() and uint64_to_nicestr()
  18 static char bufs[4][128];
  19
  20 /// Thousand separator support in uint64_to_str() and uint64_to_nicestr()
  21 static enum { UNKNOWN, WORKS, BROKEN } thousand = UNKNOWN;
  22
  23
  24 extern void *
  25 xrealloc(void *ptr, size_t size)
  26 {
  27         assert(size > 0);
  28
  29         ptr = realloc(ptr, size);
  30         if (ptr == NULL)
  31                 message_fatal("%s", strerror(errno));
  32
  33         return ptr;
  34 }
  35
  36
  37 extern char *
  38 xstrdup(const char *src)
  39 {
  40         assert(src != NULL);
  41         const size_t size = strlen(src) + 1;
  42         char *dest = xmalloc(size);
  43         return memcpy(dest, src, size);
  44 }
  45
  46
  47 extern uint64_t
  48 str_to_uint64(const char *name, const char *value, uint64_t min, uint64_t max)
  49 {
  50         uint64_t result = 0;
  51
  52         // Skip blanks.
  53         while (*value == ' ' || *value == '\t')
  54                 ++value;
  55
  56         // Accept special value "max". Supporting "min" doesn't seem useful.
  57         if (strcmp(value, "max") == 0)
  58                 return max;
  59
  60         if (*value < '0' || *value > '9')
  61                 message_fatal(_("%s: Value is not a non-negative "
  62                                 "decimal integer"), value);
  63
  64         do {
  65                 // Don't overflow.
  66                 if (result > UINT64_MAX / 10)
  67                         goto error;
  68
  69                 result *= 10;
  70
  71                 // Another overflow check
  72                 const uint32_t add = *value - '0';
  73                 if (UINT64_MAX - add < result)
  74                         goto error;
  75
  76                 result += add;
  77                 ++value;
  78         } while (*value >= '0' && *value <= '9');
  79
  80         if (*value != '\0') {
  81                 // Look for suffix. Originally this supported both base-2
  82                 // and base-10, but since there seems to be little need
  83                 // for base-10 in this program, treat everything as base-2
  84                 // and also be more relaxed about the case of the first
  85                 // letter of the suffix.
  86                 uint64_t multiplier = 0;
  87                 if (*value == 'k' || *value == 'K')
  88                         multiplier = UINT64_C(1) << 10;
  89                 else if (*value == 'm' || *value == 'M')
  90                         multiplier = UINT64_C(1) << 20;
  91                 else if (*value == 'g' || *value == 'G')
  92                         multiplier = UINT64_C(1) << 30;
  93
  94                 ++value;
  95
  96                 // Allow also e.g. Ki, KiB, and KB.
  97                 if (*value != '\0' && strcmp(value, "i") != 0
  98                                 && strcmp(value, "iB") != 0
  99                                 && strcmp(value, "B") != 0)
 100                         multiplier = 0;
 101
 102                 if (multiplier == 0) {
 103                         message(V_ERROR, _("%s: Invalid multiplier suffix"),
 104                                         value - 1);
 105                         message_fatal(_("Valid suffixes are `KiB' (2^10), "
 106                                         "`MiB' (2^20), and `GiB' (2^30)."));
 107                 }
 108
 109                 // Don't overflow here either.
 110                 if (result > UINT64_MAX / multiplier)
 111                         goto error;
 112
 113                 result *= multiplier;
 114         }
 115
 116         if (result < min || result > max)
 117                 goto error;
 118
 119         return result;
 120
 121 error:
 122         message_fatal(_("Value of the option `%s' must be in the range "
 123                                 "[%" PRIu64 ", %" PRIu64 "]"),
 124                                 name, min, max);
 125 }
 126
 127
 128 extern uint64_t
 129 round_up_to_mib(uint64_t n)
 130 {
 131         return (n >> 20) + ((n & ((UINT32_C(1) << 20) - 1)) != 0);
 132 }
 133
 134
 135 /// Check if thousand separator is supported. Run-time checking is easiest,
 136 /// because it seems to be sometimes lacking even on POSIXish system.
 137 static void
 138 check_thousand_sep(uint32_t slot)
 139 {
 140         if (thousand == UNKNOWN) {
 141                 bufs[slot][0] = '\0';
 142                 snprintf(bufs[slot], sizeof(bufs[slot]), "%'u", 1U);
 143                 thousand = bufs[slot][0] == '1' ? WORKS : BROKEN;
 144         }
 145
 146         return;
 147 }
 148
 149
 150 extern const char *
 151 uint64_to_str(uint64_t value, uint32_t slot)
 152 {
 153         assert(slot < ARRAY_SIZE(bufs));
 154
 155         check_thousand_sep(slot);
 156
 157         if (thousand == WORKS)
 158                 snprintf(bufs[slot], sizeof(bufs[slot]), "%'" PRIu64, value);
 159         else
 160                 snprintf(bufs[slot], sizeof(bufs[slot]), "%" PRIu64, value);
 161
 162         return bufs[slot];
 163 }
 164
 165
 166 extern const char *
 167 uint64_to_nicestr(uint64_t value, enum nicestr_unit unit_min,
 168                 enum nicestr_unit unit_max, bool always_also_bytes,
 169                 uint32_t slot)
 170 {
 171         assert(unit_min <= unit_max);
 172         assert(unit_max <= NICESTR_TIB);
 173         assert(slot < ARRAY_SIZE(bufs));
 174
 175         check_thousand_sep(slot);
 176
 177         enum nicestr_unit unit = NICESTR_B;
 178         char *pos = bufs[slot];
 179         size_t left = sizeof(bufs[slot]);
 180
 181         if ((unit_min == NICESTR_B && value < 10000)
 182                         || unit_max == NICESTR_B) {
 183                 // The value is shown as bytes.
 184                 if (thousand == WORKS)
 185                         my_snprintf(&pos, &left, "%'u", (unsigned int)value);
 186                 else
 187                         my_snprintf(&pos, &left, "%u", (unsigned int)value);
 188         } else {
 189                 // Scale the value to a nicer unit. Unless unit_min and
 190                 // unit_max limit us, we will show at most five significant
 191                 // digits with one decimal place.
 192                 double d = (double)(value);
 193                 do {
 194                         d /= 1024.0;
 195                         ++unit;
 196                 } while (unit < unit_min || (d > 9999.9 && unit < unit_max));
 197
 198                 if (thousand == WORKS)
 199                         my_snprintf(&pos, &left, "%'.1f", d);
 200                 else
 201                         my_snprintf(&pos, &left, "%.1f", d);
 202         }
 203
 204         static const char suffix[5][4] = { "B", "KiB", "MiB", "GiB", "TiB" };
 205         my_snprintf(&pos, &left, " %s", suffix[unit]);
 206
 207         if (always_also_bytes && value >= 10000) {
 208                 if (thousand == WORKS)
 209                         snprintf(pos, left, " (%'" PRIu64 " B)", value);
 210                 else
 211                         snprintf(pos, left, " (%" PRIu64 " B)", value);
 212         }
 213
 214         return bufs[slot];
 215 }
 216
 217
 218 extern void
 219 my_snprintf(char **pos, size_t *left, const char *fmt, ...)
 220 {
 221         va_list ap;
 222         va_start(ap, fmt);
 223         const int len = vsnprintf(*pos, *left, fmt, ap);
 224         va_end(ap);
 225
 226         // If an error occurred, we want the caller to think that the whole
 227         // buffer was used. This way no more data will be written to the
 228         // buffer. We don't need better error handling here, although it
 229         // is possible that the result looks garbage on the terminal if
 230         // e.g. an UTF-8 character gets split. That shouldn't (easily)
 231         // happen though, because the buffers used have some extra room.
 232         if (len < 0 || (size_t)(len) >= *left) {
 233                 *left = 0;
 234         } else {
 235                 *pos += len;
 236                 *left -= len;
 237         }
 238
 239         return;
 240 }
 241
 242
 243 extern bool
 244 is_empty_filename(const char *filename)
 245 {
 246         if (filename[0] == '\0') {
 247                 message_error(_("Empty filename, skipping"));
 248                 return true;
 249         }
 250
 251         return false;
 252 }
 253
 254
 255 extern bool
 256 is_tty_stdin(void)
 257 {
 258         const bool ret = isatty(STDIN_FILENO);
 259
 260         if (ret)
 261                 message_error(_("Compressed data cannot be read from "
 262                                 "a terminal"));
 263
 264         return ret;
 265 }
 266
 267
 268 extern bool
 269 is_tty_stdout(void)
 270 {
 271         const bool ret = isatty(STDOUT_FILENO);
 272
 273         if (ret)
 274                 message_error(_("Compressed data cannot be written to "
 275                                 "a terminal"));
 276
 277         return ret;
 278 }