release/src/router/busybox/libbb/printable_string.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Unicode support routines.
   4  *
   5  * Copyright (C) 2010 Denys Vlasenko
   6  *
   7  * Licensed under GPLv2, see file LICENSE in this source tree.
   8  */
   9 #include "libbb.h"
  10 #include "unicode.h"
  11
  12 const char* FAST_FUNC printable_string(uni_stat_t *stats, const char *str)
  13 {
  14         static char *saved[4];
  15         static unsigned cur_saved; /* = 0 */
  16
  17         char *dst;
  18         const char *s;
  19
  20         s = str;
  21         while (1) {
  22                 unsigned char c = *s;
  23                 if (c == '\0') {
  24                         /* 99+% of inputs do not need conversion */
  25                         if (stats) {
  26                                 stats->byte_count = (s - str);
  27                                 stats->unicode_count = (s - str);
  28                                 stats->unicode_width = (s - str);
  29                         }
  30                         return str;
  31                 }
  32                 if (c < ' ')
  33                         break;
  34                 if (c >= 0x7f)
  35                         break;
  36                 s++;
  37         }
  38
  39 #if ENABLE_UNICODE_SUPPORT
  40         dst = unicode_conv_to_printable(stats, str);
  41 #else
  42         {
  43                 char *d = dst = xstrdup(str);
  44                 while (1) {
  45                         unsigned char c = *d;
  46                         if (c == '\0')
  47                                 break;
  48                         if (c < ' ' || c >= 0x7f)
  49                                 *d = '?';
  50                         d++;
  51                 }
  52                 if (stats) {
  53                         stats->byte_count = (d - dst);
  54                         stats->unicode_count = (d - dst);
  55                         stats->unicode_width = (d - dst);
  56                 }
  57         }
  58 #endif
  59
  60         free(saved[cur_saved]);
  61         saved[cur_saved] = dst;
  62         cur_saved = (cur_saved + 1) & (ARRAY_SIZE(saved)-1);
  63
  64         return dst;
  65 }