source/lib/util_unistr.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba utility functions
   4    Copyright (C) Andrew Tridgell 1992-2001
   5    Copyright (C) Simo Sorce 2001
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23 #include "system/iconv.h"
  24
  25 /* these 2 tables define the unicode case handling.  They are loaded
  26    at startup either via mmap() or read() from the lib directory */
  27 static void *upcase_table;
  28 static void *lowcase_table;
  29
  30
  31 /*******************************************************************
  32 load the case handling tables
  33 ********************************************************************/
  34 static void load_case_tables(void)
  35 {
  36         TALLOC_CTX *mem_ctx;
  37
  38         mem_ctx = talloc_init("load_case_tables");
  39         if (!mem_ctx) {
  40                 smb_panic("No memory for case_tables");
  41         }
  42         upcase_table = map_file(lib_path(mem_ctx, "upcase.dat"), 0x20000);
  43         lowcase_table = map_file(lib_path(mem_ctx, "lowcase.dat"), 0x20000);
  44         talloc_free(mem_ctx);
  45         if (upcase_table == NULL) {
  46                 upcase_table = (void *)-1;
  47         }
  48         if (lowcase_table == NULL) {
  49                 lowcase_table = (void *)-1;
  50         }
  51 }
  52
  53 /*******************************************************************
  54  Convert a codepoint_t to upper case.
  55 ********************************************************************/
  56 codepoint_t toupper_w(codepoint_t val)
  57 {
  58         if (val < 128) {
  59                 return toupper(val);
  60         }
  61         if (upcase_table == (void *)-1) {
  62                 return val;
  63         }
  64         if (upcase_table == NULL) {
  65                 load_case_tables();
  66         }
  67         if (val & 0xFFFF0000) {
  68                 return val;
  69         }
  70         return SVAL(upcase_table, val*2);
  71 }
  72
  73 /*******************************************************************
  74  Convert a codepoint_t to lower case.
  75 ********************************************************************/
  76 codepoint_t tolower_w(codepoint_t val)
  77 {
  78         if (val < 128) {
  79                 return tolower(val);
  80         }
  81         if (lowcase_table == (void *)-1) {
  82                 return val;
  83         }
  84         if (lowcase_table == NULL) {
  85                 load_case_tables();
  86         }
  87         if (val & 0xFFFF0000) {
  88                 return val;
  89         }
  90         return SVAL(lowcase_table, val*2);
  91 }
  92
  93 /*******************************************************************
  94 return the number of bytes occupied by a buffer in CH_UTF16 format
  95 the result includes the null termination
  96 ********************************************************************/
  97 size_t utf16_len(const void *buf)
  98 {
  99         size_t len;
 100
 101         for (len = 0; SVAL(buf,len); len += 2) ;
 102
 103         return len + 2;
 104 }
 105
 106 /*******************************************************************
 107 return the number of bytes occupied by a buffer in CH_UTF16 format
 108 the result includes the null termination
 109 limited by 'n' bytes
 110 ********************************************************************/
 111 size_t utf16_len_n(const void *src, size_t n)
 112 {
 113         size_t len;
 114
 115         for (len = 0; (len+2 < n) && SVAL(src, len); len += 2) ;
 116
 117         if (len+2 <= n) {
 118                 len += 2;
 119         }
 120
 121         return len;
 122 }
 123
 124
 125 size_t ucs2_align(const void *base_ptr, const void *p, int flags)
 126 {
 127         if (flags & (STR_NOALIGN|STR_ASCII))
 128                 return 0;
 129         return PTR_DIFF(p, base_ptr) & 1;
 130 }
 131
 132 /*
 133   compare two codepoints case insensitively
 134 */
 135 int codepoint_cmpi(codepoint_t c1, codepoint_t c2)
 136 {
 137         if (c1 == c2 ||
 138             toupper_w(c1) == toupper_w(c2)) {
 139                 return 0;
 140         }
 141         return c1 - c2;
 142 }