| /* Recode strings between character sets, using iconv. |
| Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc. |
| |
| This program is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public License as |
| published by the Free Software Foundation; either version 2.1, or (at |
| your option) any later version. |
| |
| This program 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 Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License along |
| with this program; if not, write to the Free Software Foundation, |
| Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| |
| #ifdef HAVE_CONFIG_H |
| # include <config.h> |
| #endif |
| |
| /* Get prototype. */ |
| #include "iconvme.h" |
| |
| /* Get malloc. */ |
| #include <stdlib.h> |
| |
| /* Get strcmp. */ |
| #include <string.h> |
| |
| /* Get errno. */ |
| #include <errno.h> |
| |
| #ifdef _LIBC |
| # define HAVE_ICONV 1 |
| #else |
| /* Get strdup. */ |
| # include "strdup.h" |
| #endif |
| |
| #if HAVE_ICONV |
| /* Get iconv etc. */ |
| # include <iconv.h> |
| /* Get MB_LEN_MAX, CHAR_BIT. */ |
| # include <limits.h> |
| #endif |
| |
| #ifndef SIZE_MAX |
| # define SIZE_MAX ((size_t) -1) |
| #endif |
| |
| /* Convert a zero-terminated string STR from the FROM_CODSET code set |
| to the TO_CODESET code set. The returned string is allocated using |
| malloc, and must be dellocated by the caller using free. On |
| failure, NULL is returned and errno holds the error reason. Note |
| that if TO_CODESET uses \0 for anything but to terminate the |
| string, the caller of this function may have difficulties finding |
| out the length of the output string. */ |
| char * |
| iconv_string (const char *str, const char *from_codeset, |
| const char *to_codeset) |
| { |
| char *dest = NULL; |
| #if HAVE_ICONV |
| iconv_t cd; |
| char *outp; |
| char *p = (char *) str; |
| size_t inbytes_remaining = strlen (p); |
| /* Guess the maximum length the output string can have. */ |
| size_t outbuf_size = inbytes_remaining + 1; |
| size_t outbytes_remaining; |
| size_t err; |
| int have_error = 0; |
| |
| /* Use a worst-case output size guess, so long as that wouldn't be |
| too large for comfort. It's OK if the guess is wrong so long as |
| it's nonzero. */ |
| size_t approx_sqrt_SIZE_MAX = SIZE_MAX >> (sizeof (size_t) * CHAR_BIT / 2); |
| if (outbuf_size <= approx_sqrt_SIZE_MAX / MB_LEN_MAX) |
| outbuf_size *= MB_LEN_MAX; |
| outbytes_remaining = outbuf_size - 1; |
| #endif |
| |
| if (strcmp (to_codeset, from_codeset) == 0) |
| return strdup (str); |
| |
| #if HAVE_ICONV |
| cd = iconv_open (to_codeset, from_codeset); |
| if (cd == (iconv_t) -1) |
| return NULL; |
| |
| outp = dest = (char *) malloc (outbuf_size); |
| if (dest == NULL) |
| goto out; |
| |
| again: |
| err = iconv (cd, &p, &inbytes_remaining, &outp, &outbytes_remaining); |
| |
| if (err == (size_t) - 1) |
| { |
| switch (errno) |
| { |
| case EINVAL: |
| /* Incomplete text, do not report an error */ |
| break; |
| |
| case E2BIG: |
| { |
| size_t used = outp - dest; |
| size_t newsize = outbuf_size * 2; |
| char *newdest; |
| |
| if (newsize <= outbuf_size) |
| { |
| errno = ENOMEM; |
| have_error = 1; |
| goto out; |
| } |
| newdest = (char *) realloc (dest, newsize); |
| if (newdest == NULL) |
| { |
| have_error = 1; |
| goto out; |
| } |
| dest = newdest; |
| outbuf_size = newsize; |
| |
| outp = dest + used; |
| outbytes_remaining = outbuf_size - used - 1; /* -1 for NUL */ |
| |
| goto again; |
| } |
| break; |
| |
| case EILSEQ: |
| have_error = 1; |
| break; |
| |
| default: |
| have_error = 1; |
| break; |
| } |
| } |
| |
| *outp = '\0'; |
| |
| out: |
| { |
| int save_errno = errno; |
| |
| if (iconv_close (cd) < 0 && !have_error) |
| { |
| /* If we didn't have a real error before, make sure we restore |
| the iconv_close error below. */ |
| save_errno = errno; |
| have_error = 1; |
| } |
| |
| if (have_error && dest) |
| { |
| free (dest); |
| dest = NULL; |
| errno = save_errno; |
| } |
| } |
| #else |
| errno = ENOSYS; |
| #endif |
| |
| return dest; |
| } |