iconv/gconv_open.c

   1 /* Find matching transformation algorithms and initialize steps.
   2    Copyright (C) 1997, 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <errno.h>
  22 #include <stdlib.h>
  23
  24 #include <gconv_int.h>
  25
  26
  27 int
  28 internal_function
  29 __gconv_open (const char *toset, const char *fromset, gconv_t *handle)
  30 {
  31   struct gconv_step *steps;
  32   size_t nsteps;
  33   gconv_t result = NULL;
  34   size_t cnt = 0;
  35   int res;
  36
  37   res = __gconv_find_transform (toset, fromset, &steps, &nsteps);
  38   if (res == GCONV_OK)
  39     {
  40       /* Allocate room for handle.  */
  41       result = (gconv_t) malloc (sizeof (struct gconv_info));
  42       if (result == NULL)
  43         res = GCONV_NOMEM;
  44       else
  45         {
  46           /* Remember the list of steps.  */
  47           result->steps = steps;
  48           result->nsteps = nsteps;
  49
  50           /* Allocate array for the step data.  */
  51           result->data = (struct gconv_step_data *)
  52             calloc (nsteps, sizeof (struct gconv_step_data));
  53
  54           if (result->data == NULL)
  55             res = GCONV_NOMEM;
  56           else
  57             {
  58               /* Call all initialization functions for the transformation
  59                  step implemenations.  */
  60               struct gconv_step_data *data = result->data;
  61
  62               for (cnt = 0; cnt < nsteps; ++cnt)
  63                 {
  64                   /* If this is the last step we must not allocate an output
  65                      buffer.  */
  66                   data[cnt].is_last = cnt == nsteps - 1;
  67
  68                   /* Reset the counter.  */
  69                   data[cnt].invocation_counter = 0;
  70
  71                   /* It's a regular use.  */
  72                   data[cnt].internal_use = 0;
  73
  74                   /* We use the `mbstate_t' member in DATA.  */
  75                   data[cnt].statep = &data[cnt].__state;
  76
  77                   /* Allocate the buffer.  */
  78                   if (!data[cnt].is_last)
  79                     {
  80                       size_t size = (GCONV_NCHAR_GOAL
  81                                      * steps[cnt].max_needed_to);
  82
  83                       data[cnt].outbuf = (char *) malloc (size);
  84                       if (data[cnt].outbuf == NULL)
  85                         {
  86                           res = GCONV_NOMEM;
  87                           break;
  88                         }
  89                       data[cnt].outbufend = data[cnt].outbuf + size;
  90                     }
  91                 }
  92             }
  93         }
  94     }
  95
  96   if (res != GCONV_OK)
  97     {
  98       /* Something went wrong.  Free all the resources.  */
  99       int serrno = errno;
 100
 101       if (result != NULL)
 102         {
 103           if (result->data != NULL)
 104             {
 105               while (cnt-- > 0)
 106                 free (result->data[cnt].outbuf);
 107
 108               free (result->data);
 109             }
 110
 111           free (result);
 112           result = NULL;
 113         }
 114
 115       __gconv_close_transform (steps, nsteps);
 116
 117       __set_errno (serrno);
 118     }
 119
 120   *handle = result;
 121   return res;
 122 }