Line data    Source code

       1             : /* gunicode.c - Unicode manipulation functions
       2             :  *
       3             :  *  Copyright (C) 1999, 2000 Tom Tromey
       4             :  *  Copyright 2000, 2005 Red Hat, Inc.
       5             :  */
       6             : 
       7             : #include "gunicode.h"
       8             : 
       9             : #define unichar uint32_t
      10             : 
      11             : /**
      12             :  * g_utf8_prev_char:
      13             :  * @p: a pointer to a position within a UTF-8 encoded string
      14             :  *
      15             :  * Finds the previous UTF-8 character in the string before @p.
      16             :  *
      17             :  * @p does not have to be at the beginning of a UTF-8 character. No check
      18             :  * is made to see if the character found is actually valid other than
      19             :  * it starts with an appropriate byte. If @p might be the first
      20             :  * character of the string, you must use g_utf8_find_prev_char() instead.
      21             :  *
      22             :  * Return value: a pointer to the found character.
      23             :  **/
      24             : char *
      25         186 : utf8_prev_char (const char *p)
      26             : {
      27             :   while (1)
      28             :     {
      29         186 :       p--;
      30         186 :       if ((*p & 0xc0) != 0x80)
      31         144 :         return (char *)p;
      32         114 :     }
      33             : }
      34             : 
      35             : struct Interval
      36             : {
      37             :   unichar start, end;
      38             : };
      39             : 
      40             : static int
      41        1286 : interval_compare (const void *key, const void *elt)
      42             : {
      43        1286 :   unichar c = (unichar) (long) (key);
      44        1286 :   struct Interval *interval = (struct Interval *)elt;
      45             : 
      46        1286 :   if (c < interval->start)
      47         726 :     return -1;
      48         560 :   if (c > interval->end)
      49         400 :     return +1;
      50             : 
      51         160 :   return 0;
      52             : }
      53             : 
      54             : /*
      55             :  * NOTE:
      56             :  *
      57             :  * The tables for g_unichar_iswide() and g_unichar_iswide_cjk() are
      58             :  * generated from the Unicode Character Database's file
      59             :  * extracted/DerivedEastAsianWidth.txt using the gen-iswide-table.py
      60             :  * in this way:
      61             :  *
      62             :  *   ./gen-iswide-table.py < path/to/ucd/extracted/DerivedEastAsianWidth.txt | fmt
      63             :  *
      64             :  * Last update for Unicode 6.0.
      65             :  */
      66             : 
      67             : /**
      68             :  * g_unichar_iswide:
      69             :  * @c: a Unicode character
      70             :  *
      71             :  * Determines if a character is typically rendered in a double-width
      72             :  * cell.
      73             :  *
      74             :  * Return value: %TRUE if the character is wide
      75             :  **/
      76             : bool
      77         241 : unichar_iswide (unichar c)
      78             : {
      79             :   /* See NOTE earlier for how to update this table. */
      80             :   static const struct Interval wide[] = {
      81             :     {0x1100, 0x115F}, {0x2329, 0x232A}, {0x2E80, 0x2E99}, {0x2E9B, 0x2EF3},
      82             :     {0x2F00, 0x2FD5}, {0x2FF0, 0x2FFB}, {0x3000, 0x303E}, {0x3041, 0x3096},
      83             :     {0x3099, 0x30FF}, {0x3105, 0x312D}, {0x3131, 0x318E}, {0x3190, 0x31BA},
      84             :     {0x31C0, 0x31E3}, {0x31F0, 0x321E}, {0x3220, 0x3247}, {0x3250, 0x32FE},
      85             :     {0x3300, 0x4DBF}, {0x4E00, 0xA48C}, {0xA490, 0xA4C6}, {0xA960, 0xA97C},
      86             :     {0xAC00, 0xD7A3}, {0xF900, 0xFAFF}, {0xFE10, 0xFE19}, {0xFE30, 0xFE52},
      87             :     {0xFE54, 0xFE66}, {0xFE68, 0xFE6B}, {0xFF01, 0xFF60}, {0xFFE0, 0xFFE6},
      88             :     {0x1B000, 0x1B001}, {0x1F200, 0x1F202}, {0x1F210, 0x1F23A},
      89             :     {0x1F240, 0x1F248}, {0x1F250, 0x1F251},
      90             :     {0x1F300, 0x1F567}, /* Miscellaneous Symbols and Pictographs */
      91             :     {0x20000, 0x2FFFD}, {0x30000, 0x3FFFD},
      92             :   };
      93             : 
      94         241 :   if (bsearch ((void *)(uintptr_t)c, wide, (sizeof (wide) / sizeof ((wide)[0])), sizeof wide[0],
      95             :                interval_compare))
      96         160 :     return true;
      97             : 
      98          81 :   return false;
      99             : }
     100             : 
     101             : const char utf8_skip_data[256] = {
     102             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     103             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     104             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     105             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     106             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     107             :   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
     108             :   2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
     109             :   3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1
     110             : };