usr/src/boot/sys/boot/efi/libefi/efichar.c

   1 /*
   2  * Copyright (c) 2010 Marcel Moolenaar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28
  29 #include <sys/types.h>
  30 #include <errno.h>
  31 #include <stand.h>
  32 #include <efichar.h>
  33
  34 int
  35 ucs2len(const CHAR16 *str)
  36 {
  37         int i;
  38
  39         i = 0;
  40         while (*str++)
  41                 i++;
  42         return (i);
  43 }
  44
  45 /*
  46  * If nm were converted to utf8, what what would strlen
  47  * return on the resulting string?
  48  */
  49 static size_t
  50 utf8_len_of_ucs2(const CHAR16 *nm)
  51 {
  52         size_t len;
  53         CHAR16 c;
  54
  55         len = 0;
  56         while (*nm) {
  57                 c = *nm++;
  58                 if (c > 0x7ff)
  59                         len += 3;
  60                 else if (c > 0x7f)
  61                         len += 2;
  62                 else
  63                         len++;
  64         }
  65
  66         return (len);
  67 }
  68
  69 int
  70 ucs2_to_utf8(const CHAR16 *nm, char **name)
  71 {
  72         size_t len, sz;
  73         CHAR16 c;
  74         char *cp;
  75         int freeit = *name == NULL;
  76
  77         sz = utf8_len_of_ucs2(nm) + 1;
  78         len = 0;
  79         if (*name != NULL)
  80                 cp = *name;
  81         else
  82                 cp = *name = malloc(sz);
  83         if (*name == NULL)
  84                 return (ENOMEM);
  85
  86         while (*nm) {
  87                 c = *nm++;
  88                 if (c > 0x7ff) {
  89                         if (len++ < sz)
  90                                 *cp++ = (char)(0xE0 | (c >> 12));
  91                         if (len++ < sz)
  92                                 *cp++ = (char)(0x80 | ((c >> 6) & 0x3f));
  93                         if (len++ < sz)
  94                                 *cp++ = (char)(0x80 | (c & 0x3f));
  95                 } else if (c > 0x7f) {
  96                         if (len++ < sz)
  97                                 *cp++ = (char)(0xC0 | ((c >> 6) & 0x1f));
  98                         if (len++ < sz)
  99                                 *cp++ = (char)(0x80 | (c & 0x3f));
 100                 } else {
 101                         if (len++ < sz)
 102                                 *cp++ = (char)(c & 0x7f);
 103                 }
 104         }
 105
 106         if (len >= sz) {
 107                 /* Absent bugs, we'll never return EOVERFLOW */
 108                 if (freeit) {
 109                         free(*name);
 110                         *name = NULL;
 111                 }
 112                 return (EOVERFLOW);
 113         }
 114         *cp++ = '\0';
 115
 116         return (0);
 117 }
 118
 119 int
 120 utf8_to_ucs2(const char *name, CHAR16 **nmp, size_t *len)
 121 {
 122         CHAR16 *nm;
 123         size_t sz;
 124         uint32_t ucs4;
 125         int c, bytes;
 126         int freeit = *nmp == NULL;
 127
 128         sz = strlen(name) * 2 + 2;
 129         if (*nmp == NULL)
 130                 *nmp = malloc(sz);
 131         if (*nmp == NULL)
 132                 return (ENOMEM);
 133         nm = *nmp;
 134         *len = sz;
 135
 136         ucs4 = 0;
 137         bytes = 0;
 138         while (sz > 1 && *name != '\0') {
 139                 c = *name++;
 140                 /*
 141                  * Conditionalize on the two major character types:
 142                  * initial and followup characters.
 143                  */
 144                 if ((c & 0xc0) != 0x80) {
 145                         /* Initial characters. */
 146                         if (bytes != 0)
 147                                 goto ilseq;
 148                         if ((c & 0xf8) == 0xf0) {
 149                                 ucs4 = c & 0x07;
 150                                 bytes = 3;
 151                         } else if ((c & 0xf0) == 0xe0) {
 152                                 ucs4 = c & 0x0f;
 153                                 bytes = 2;
 154                         } else if ((c & 0xe0) == 0xc0) {
 155                                 ucs4 = c & 0x1f;
 156                                 bytes = 1;
 157                         } else {
 158                                 ucs4 = c & 0x7f;
 159                                 bytes = 0;
 160                         }
 161                 } else {
 162                         /* Followup characters. */
 163                         if (bytes > 0) {
 164                                 ucs4 = (ucs4 << 6) + (c & 0x3f);
 165                                 bytes--;
 166                         } else if (bytes == 0) {
 167                                 goto ilseq;
 168                         }
 169                 }
 170                 if (bytes == 0) {
 171                         if (ucs4 > 0xffff)
 172                                 goto ilseq;
 173                         *nm++ = (CHAR16)ucs4;
 174                         sz -= 2;
 175                 }
 176         }
 177         if (sz < 2) {
 178                 if (freeit) {
 179                         free(nm);
 180                         *nmp = NULL;
 181                 }
 182                 return (EDOOFUS);
 183         }
 184         sz -= 2;
 185         *nm = 0;
 186         *len -= sz;
 187         return (0);
 188 ilseq:
 189         if (freeit) {
 190                 free(nm);
 191                 *nmp = NULL;
 192         }
 193         return (EILSEQ);
 194 }