guacamole-spice-protocol/src/protocols/vnc/convert.c
2013-06-05 11:00:28 -07:00

117 lines
4.0 KiB
C

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is libguac-client-vnc.
*
* The Initial Developer of the Original Code is
* James Muehlner.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdlib.h>
#include <string.h>
#include <iconv.h>
#include <errno.h>
char* convert(const char* from_charset, const char* to_charset, const char* input) {
size_t input_remaining;
size_t output_remaining;
size_t bytes_converted = 0;
char* output;
char* output_buffer;
char* new_buffer;
char* input_buffer;
size_t output_length;
iconv_t cd;
cd = iconv_open(to_charset, from_charset);
if(cd == (iconv_t) -1)
/* Cannot convert due to invalid character set */
return NULL;
input_remaining = strlen(input);
input_buffer = (char*) input;
/* Start the output buffer the same size as the input buffer */
output_length = input_remaining;
/* Leave some space at the end for NULL terminator */
if (!(output = (char*) malloc(output_length + 4))) {
/* Cannot convert due to memory allocation error */
iconv_close(cd);
return NULL;
}
do {
output_buffer = output + bytes_converted;
output_remaining = output_length - bytes_converted;
bytes_converted = iconv(cd, &input_buffer,
&input_remaining, &output_buffer, &output_remaining);
if(bytes_converted == -1) {
if(errno == E2BIG) {
/* The output buffer is too small, so allocate more space */
bytes_converted = output_buffer - output;
output_length += input_remaining * 2 + 8;
if (!(new_buffer = (char*) realloc(output, output_length + 4))) {
/* Cannot convert due to memory allocation error */
iconv_close(cd);
free(output);
return NULL;
}
output = new_buffer;
output_buffer = output + bytes_converted;
}
else if (errno == EILSEQ) {
/* Invalid sequence detected, return what's been converted so far */
break;
}
else if (errno == EINVAL) {
/* Incomplete sequence detected, can be ignored */
break;
}
}
} while (input_remaining);
/* Flush the iconv conversion */
iconv(cd, NULL, NULL, &output_buffer, &output_remaining);
iconv_close(cd);
/* Add the NULL terminator */
memset(output_buffer, 0, 4);
return output;
}