actube/src/cw/format_is_utf8.c

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/*
This file is part of actube.
actube is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
libcapwap 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file
* @brief Implementation for format_is_utf8
*/
#include "format.h"
/**
* Check if a string is in UTF8 format
* @param str String to check
* @param len Length of the string
* @return 0 if the string is not in UTF8 format, otherwise it is UTF8.
*/
int format_is_utf8(unsigned char *str, size_t len)
{
size_t i = 0;
size_t bytes = 0;
while (i < len) {
if (str[i] < 0x20) {
return 0;
}
if (str[i] <= 0x7F)
bytes = 0;
else if (str[i] >= 0xC0 /*11000000 */ && str[i] <= 0xDF /*11011111 */ )
bytes = 1;
else if (str[i] >= 0xE0 /*11100000 */ && str[i] <= 0xEF /*11101111 */ )
bytes = 2;
else if (str[i] >= 0xF0 /*11110000 */
&& str[i] <= 0xF4 /* Cause of RFC 3629 */ )
bytes = 3;
else {
return 0;
}
i += 1;
while (i < len && bytes > 0 && str[i] >= 0x80 && str[i] <= 0xBF) {
i += 1;
bytes -= 1;
}
if (bytes != 0) {
return 0;
}
}
return 1;
}