iconv/iconv.c

   1 /* Convert characters in input buffer using conversion descriptor to
   2    output buffer.
   3    Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library 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 GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include <stddef.h> /* for NULL */
  23 #include <errno.h>
  24 #include <iconv.h>
  25
  26 #include <gconv_int.h>
  27
  28 #include <assert.h>
  29
  30
  31 size_t
  32 iconv (iconv_t cd, char **inbuf, size_t *inbytesleft, char **outbuf,
  33        size_t *outbytesleft)
  34 {
  35   __gconv_t gcd = (__gconv_t) cd;
  36   char *outstart = outbuf ? *outbuf : NULL;
  37   size_t converted;
  38   int result;
  39
  40   if (__builtin_expect (inbuf == NULL || *inbuf == NULL, 0))
  41     {
  42       if (outbuf == NULL || *outbuf == NULL)
  43         result = __gconv (gcd, NULL, NULL, NULL, NULL, &converted);
  44       else
  45         result = __gconv (gcd, NULL, NULL, (unsigned char **) outbuf,
  46                           (unsigned char *) (outstart + *outbytesleft),
  47                           &converted);
  48     }
  49   else
  50     {
  51       const char *instart = *inbuf;
  52
  53       result = __gconv (gcd, (const unsigned char **) inbuf,
  54                         (const unsigned char *)  (*inbuf + *inbytesleft),
  55                         (unsigned char **) outbuf,
  56                         (unsigned char *) (*outbuf + *outbytesleft),
  57                         &converted);
  58
  59       *inbytesleft -= *inbuf - instart;
  60     }
  61   if (outstart != NULL)
  62     *outbytesleft -= *outbuf - outstart;
  63
  64   switch (__builtin_expect (result, __GCONV_OK))
  65     {
  66     case __GCONV_ILLEGAL_DESCRIPTOR:
  67       __set_errno (EBADF);
  68       converted = (size_t) -1L;
  69       break;
  70
  71     case __GCONV_ILLEGAL_INPUT:
  72       __set_errno (EILSEQ);
  73       converted = (size_t) -1L;
  74       break;
  75
  76     case __GCONV_FULL_OUTPUT:
  77       __set_errno (E2BIG);
  78       converted = (size_t) -1L;
  79       break;
  80
  81     case __GCONV_INCOMPLETE_INPUT:
  82       __set_errno (EINVAL);
  83       converted = (size_t) -1L;
  84       break;
  85
  86     case __GCONV_EMPTY_INPUT:
  87     case __GCONV_OK:
  88       /* Nothing.  */
  89       break;
  90
  91     default:
  92       assert (!"Nothing like this should happen");
  93     }
  94
  95   return converted;
  96 }