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/* Copyright (C) 2009 Codership Oy <info@codersihp.com>
This program 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; version 2 of the License.
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 General Public License for more details.
You should have received a copy of the GNU 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
*/
/*! @file Helper functions to deal with history UUID string representations */
#include <errno.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include "wsrep_api.h"
/*!
* Read UUID from string
* @return length of UUID string representation or -EINVAL in case of error
*/
int
wsrep_uuid_scan (const char* str, size_t str_len, wsrep_uuid_t* uuid)
{
unsigned int uuid_len = 0;
unsigned int uuid_offt = 0;
while (uuid_len + 1 < str_len) {
/* We are skipping potential '-' after uuid_offt == 4, 6, 8, 10
* which means
* (uuid_offt >> 1) == 2, 3, 4, 5,
* which in turn means
* (uuid_offt >> 1) - 2 <= 3
* since it is always >= 0, because uuid_offt is unsigned */
if (((uuid_offt >> 1) - 2) <= 3 && str[uuid_len] == '-') {
// skip dashes after 4th, 6th, 8th and 10th positions
uuid_len += 1;
continue;
}
if (isxdigit(str[uuid_len]) && isxdigit(str[uuid_len + 1])) {
// got hex digit, scan another byte to uuid, increment uuid_offt
sscanf (str + uuid_len, "%2hhx", uuid->data + uuid_offt);
uuid_len += 2;
uuid_offt += 1;
if (sizeof (uuid->data) == uuid_offt)
return (int)uuid_len;
}
else {
break;
}
}
*uuid = WSREP_UUID_UNDEFINED;
return -EINVAL;
}
/*!
* Write UUID to string
* @return length of UUID string representation or -EMSGSIZE if string is too
* short
*/
int
wsrep_uuid_print (const wsrep_uuid_t* uuid, char* str, size_t str_len)
{
if (str_len > 36) {
const unsigned char* u = uuid->data;
return snprintf(str, str_len, "%02x%02x%02x%02x-%02x%02x-%02x%02x-"
"%02x%02x-%02x%02x%02x%02x%02x%02x",
u[ 0], u[ 1], u[ 2], u[ 3], u[ 4], u[ 5], u[ 6], u[ 7],
u[ 8], u[ 9], u[10], u[11], u[12], u[13], u[14], u[15]);
}
else {
return -EMSGSIZE;
}
}
/*!
* Compare two UUIDs
* @return -1, 0, 1 if lhs is respectively smaller, equal, or greater than rhs
*/
int
wsrep_uuid_compare (const wsrep_uuid_t* lhs, const wsrep_uuid_t* rhs)
{
return memcmp(lhs, rhs, sizeof(wsrep_uuid_t));
}
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