glibc/iconv/gconv_open.c

120 lines
3.3 KiB
C

/* Find matching transformation algorithms and initialize steps.
Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <gconv_int.h>
int
internal_function
__gconv_open (const char *toset, const char *fromset, __gconv_t *handle,
int flags)
{
struct __gconv_step *steps;
size_t nsteps;
__gconv_t result = NULL;
size_t cnt = 0;
int res;
res = __gconv_find_transform (toset, fromset, &steps, &nsteps, flags);
if (res == __GCONV_OK)
{
/* Allocate room for handle. */
result = (__gconv_t) malloc (sizeof (struct __gconv_info)
+ (nsteps
* sizeof (struct __gconv_step_data)));
if (result == NULL)
res = __GCONV_NOMEM;
else
{
/* Remember the list of steps. */
result->__steps = steps;
result->__nsteps = nsteps;
/* Clear the array for the step data. */
memset (result->__data, '\0',
nsteps * sizeof (struct __gconv_step_data));
/* Call all initialization functions for the transformation
step implementations. */
for (cnt = 0; cnt < nsteps - 1; ++cnt)
{
size_t size;
/* If this is the last step we must not allocate an
output buffer. */
result->__data[cnt].__is_last = 0;
/* Reset the counter. */
result->__data[cnt].__invocation_counter = 0;
/* It's a regular use. */
result->__data[cnt].__internal_use = 0;
/* We use the `mbstate_t' member in DATA. */
result->__data[cnt].__statep = &result->__data[cnt].__state;
/* Allocate the buffer. */
size = (GCONV_NCHAR_GOAL * steps[cnt].__max_needed_to);
result->__data[cnt].__outbuf = (char *) malloc (size);
if (result->__data[cnt].__outbuf == NULL)
{
res = __GCONV_NOMEM;
break;
}
result->__data[cnt].__outbufend =
result->__data[cnt].__outbuf + size;
}
/* Now handle the last entry. */
result->__data[cnt].__is_last = 1;
result->__data[cnt].__invocation_counter = 0;
result->__data[cnt].__internal_use = 0;
result->__data[cnt].__statep = &result->__data[cnt].__state;
}
}
if (res != __GCONV_OK)
{
/* Something went wrong. Free all the resources. */
int serrno = errno;
if (result != NULL)
{
while (cnt-- > 0)
free (result->__data[cnt].__outbuf);
free (result);
result = NULL;
}
__gconv_close_transform (steps, nsteps);
__set_errno (serrno);
}
*handle = result;
return res;
}