tor-android/external/badvpn_dns/misc/string_begins_with.h

97 lines
2.8 KiB
C
Raw Normal View History

2015-01-25 11:08:34 +00:00
/**
* @file string_begins_with.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* @section DESCRIPTION
*
* Function for checking if a string begins with a given string.
*/
#ifndef BADVPN_MISC_STRING_BEGINS_WITH
#define BADVPN_MISC_STRING_BEGINS_WITH
#include <stddef.h>
#include <string.h>
#include <misc/debug.h>
static size_t data_begins_with (const char *str, size_t str_len, const char *needle)
{
ASSERT(strlen(needle) > 0)
size_t len = 0;
while (str_len > 0 && *needle) {
if (*str != *needle) {
return 0;
}
str++;
str_len--;
needle++;
len++;
}
if (*needle) {
return 0;
}
return len;
}
static size_t string_begins_with (const char *str, const char *needle)
{
ASSERT(strlen(needle) > 0)
return data_begins_with(str, strlen(str), needle);
}
static size_t data_begins_with_bin (const char *str, size_t str_len, const char *needle, size_t needle_len)
{
ASSERT(needle_len > 0)
size_t len = 0;
while (str_len > 0 && needle_len > 0) {
if (*str != *needle) {
return 0;
}
str++;
str_len--;
needle++;
needle_len--;
len++;
}
if (needle_len > 0) {
return 0;
}
return len;
}
#endif