diff options
Diffstat (limited to 'lib/unistr/u16-to-u32.c')
-rw-r--r-- | lib/unistr/u16-to-u32.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/lib/unistr/u16-to-u32.c b/lib/unistr/u16-to-u32.c new file mode 100644 index 0000000..2f39dcd --- /dev/null +++ b/lib/unistr/u16-to-u32.c @@ -0,0 +1,125 @@ +/* Convert UTF-16 string to UTF-32 string. + Copyright (C) 2002, 2006-2007 Free Software Foundation, Inc. + Written by Bruno Haible <bruno@clisp.org>, 2002. + + 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */ + +#include <config.h> + +/* Specification. */ +#include "unistr.h" + +#define FUNC u16_to_u32 +#define SRC_UNIT uint16_t +#define DST_UNIT uint32_t + +#include <errno.h> +#include <stdlib.h> +#include <string.h> + +DST_UNIT * +FUNC (const SRC_UNIT *s, size_t n, DST_UNIT *resultbuf, size_t *lengthp) +{ + const SRC_UNIT *s_end = s + n; + /* Output string accumulator. */ + DST_UNIT *result; + size_t allocated; + size_t length; + + if (resultbuf != NULL) + { + result = resultbuf; + allocated = *lengthp; + } + else + { + result = NULL; + allocated = 0; + } + length = 0; + /* Invariants: + result is either == resultbuf or == NULL or malloc-allocated. + If length > 0, then result != NULL. */ + + while (s < s_end) + { + ucs4_t uc; + int count; + + /* Fetch a Unicode character from the input string. */ + count = u16_mbtouc (&uc, s, s_end - s); + if (count < 0) + { + if (!(result == resultbuf || result == NULL)) + free (result); + errno = EILSEQ; + return NULL; + } + s += count; + + /* Store it in the output string. */ + if (length + 1 > allocated) + { + DST_UNIT *memory; + + allocated = (allocated > 0 ? 2 * allocated : 12); + if (length + 1 > allocated) + allocated = length + 1; + if (result == resultbuf || result == NULL) + memory = (DST_UNIT *) malloc (allocated * sizeof (DST_UNIT)); + else + memory = + (DST_UNIT *) realloc (result, allocated * sizeof (DST_UNIT)); + + if (memory == NULL) + { + if (!(result == resultbuf || result == NULL)) + free (result); + errno = ENOMEM; + return NULL; + } + if (result == resultbuf && length > 0) + memcpy ((char *) memory, (char *) result, + length * sizeof (DST_UNIT)); + result = memory; + } + result[length++] = uc; + } + + if (length == 0) + { + if (result == NULL) + { + /* Return a non-NULL value. NULL means error. */ + result = (DST_UNIT *) malloc (1); + if (result == NULL) + { + errno = ENOMEM; + return NULL; + } + } + } + else if (result != resultbuf && length < allocated) + { + /* Shrink the allocated memory if possible. */ + DST_UNIT *memory; + + memory = (DST_UNIT *) realloc (result, length * sizeof (DST_UNIT)); + if (memory != NULL) + result = memory; + } + + *lengthp = length; + return result; +} |