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Diffstat (limited to 'externals/mysql/mysys/my_uuid.c')
| -rw-r--r-- | externals/mysql/mysys/my_uuid.c | 243 |
1 files changed, 0 insertions, 243 deletions
diff --git a/externals/mysql/mysys/my_uuid.c b/externals/mysql/mysys/my_uuid.c deleted file mode 100644 index 64db822cfb0..00000000000 --- a/externals/mysql/mysys/my_uuid.c +++ /dev/null @@ -1,243 +0,0 @@ -/* Copyright (C) 2007 MySQL AB, Sergei Golubchik & Michael Widenius - - 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 */ - -/* - implements Universal Unique Identifiers (UUIDs), as in - DCE 1.1: Remote Procedure Call, - Open Group Technical Standard Document Number C706, October 1997, - (supersedes C309 DCE: Remote Procedure Call 8/1994, - which was basis for ISO/IEC 11578:1996 specification) - - A UUID has the following structure: - - Field NDR Data Type Octet # Note - time_low unsigned long 0-3 The low field of the - timestamp. - time_mid unsigned short 4-5 The middle field of - the timestamp. - time_hi_and_version unsigned short 6-7 The high field of the - timestamp multiplexed - with the version number. - clock_seq_hi_and_reserved unsigned small 8 The high field of the - clock sequence multi- - plexed with the variant. - clock_seq_low unsigned small 9 The low field of the - clock sequence. - node character 10-15 The spatially unique node - identifier. -*/ - -#include "mysys_priv.h" -#include <m_string.h> -#include <myisampack.h> /* mi_int2store, mi_int4store */ - -static my_bool my_uuid_inited= 0; -static struct my_rnd_struct uuid_rand; -static uint nanoseq; -static ulonglong uuid_time= 0; -static uchar uuid_suffix[2+6]; /* clock_seq and node */ - -#ifdef THREAD -static pthread_mutex_t LOCK_uuid_generator; -#endif - -/* - Number of 100-nanosecond intervals between - 1582-10-15 00:00:00.00 and 1970-01-01 00:00:00.00 -*/ - -#define UUID_TIME_OFFSET ((ulonglong) 141427 * 24 * 60 * 60 * \ - 1000 * 1000 * 10) -#define UUID_VERSION 0x1000 -#define UUID_VARIANT 0x8000 - - -/* Helper function */ - -static void set_clock_seq() -{ - uint16 clock_seq= ((uint)(my_rnd(&uuid_rand)*16383)) | UUID_VARIANT; - mi_int2store(uuid_suffix, clock_seq); -} - - -/** - Init structures needed for my_uuid - - @func my_uuid_init() - @param seed1 Seed for random generator - @param seed2 Seed for random generator - - @note - Seed1 & seed2 should NOT depend on clock. This is to be able to - generate a random mac address according to UUID specs. -*/ - -void my_uuid_init(ulong seed1, ulong seed2) -{ - uchar *mac= uuid_suffix+2; - ulonglong now; - - if (my_uuid_inited) - return; - my_uuid_inited= 1; - now= my_getsystime(); - nanoseq= 0; - - if (my_gethwaddr(mac)) - { - uint i; - /* - Generating random "hardware addr" - - Specs explicitly specify that node identifier should NOT - correlate with a clock_seq value, so we use a separate - randominit() here. - */ - /* purecov: begin inspected */ - my_rnd_init(&uuid_rand, (ulong) (seed2+ now/2), (ulong) (now+rand())); - for (i=0; i < sizeof(mac); i++) - mac[i]= (uchar)(my_rnd(&uuid_rand)*255); - /* purecov: end */ - } - my_rnd_init(&uuid_rand, (ulong) (seed1 + now), (ulong) (now/2+ getpid())); - set_clock_seq(); - pthread_mutex_init(&LOCK_uuid_generator, MY_MUTEX_INIT_FAST); -} - - -/** - Create a global unique identifier (uuid) - - @func my_uuid() - @param to Store uuid here. Must be of size MY_uuid_SIZE (16) -*/ - -void my_uuid(uchar *to) -{ - ulonglong tv; - uint32 time_low; - uint16 time_mid, time_hi_and_version; - - DBUG_ASSERT(my_uuid_inited); - - pthread_mutex_lock(&LOCK_uuid_generator); - tv= my_getsystime() + UUID_TIME_OFFSET + nanoseq; - - if (likely(tv > uuid_time)) - { - /* - Current time is ahead of last timestamp, as it should be. - If we "borrowed time", give it back, just as long as we - stay ahead of the previous timestamp. - */ - if (nanoseq) - { - uint delta; - DBUG_ASSERT((tv > uuid_time) && (nanoseq > 0)); - /* - -1 so we won't make tv= uuid_time for nanoseq >= (tv - uuid_time) - */ - delta= min(nanoseq, (uint)(tv - uuid_time -1)); - tv-= delta; - nanoseq-= delta; - } - } - else - { - if (unlikely(tv == uuid_time)) - { - /* - For low-res system clocks. If several requests for UUIDs - end up on the same tick, we add a nano-second to make them - different. - ( current_timestamp + nanoseq * calls_in_this_period ) - may end up > next_timestamp; this is OK. Nonetheless, we'll - try to unwind nanoseq when we get a chance to. - If nanoseq overflows, we'll start over with a new numberspace - (so the if() below is needed so we can avoid the ++tv and thus - match the follow-up if() if nanoseq overflows!). - */ - if (likely(++nanoseq)) - ++tv; - } - - if (unlikely(tv <= uuid_time)) - { - /* - If the admin changes the system clock (or due to Daylight - Saving Time), the system clock may be turned *back* so we - go through a period once more for which we already gave out - UUIDs. To avoid duplicate UUIDs despite potentially identical - times, we make a new random component. - We also come here if the nanoseq "borrowing" overflows. - In either case, we throw away any nanoseq borrowing since it's - irrelevant in the new numberspace. - */ - set_clock_seq(); - tv= my_getsystime() + UUID_TIME_OFFSET; - nanoseq= 0; - DBUG_PRINT("uuid",("making new numberspace")); - } - } - - uuid_time=tv; - pthread_mutex_unlock(&LOCK_uuid_generator); - - time_low= (uint32) (tv & 0xFFFFFFFF); - time_mid= (uint16) ((tv >> 32) & 0xFFFF); - time_hi_and_version= (uint16) ((tv >> 48) | UUID_VERSION); - - /* - Note, that the standard does NOT specify byte ordering in - multi-byte fields. it's implementation defined (but must be - the same for all fields). - We use big-endian, so we can use memcmp() to compare UUIDs - and for straightforward UUID to string conversion. - */ - mi_int4store(to, time_low); - mi_int2store(to+4, time_mid); - mi_int2store(to+6, time_hi_and_version); - bmove(to+8, uuid_suffix, sizeof(uuid_suffix)); -} - - -/** - Convert uuid to string representation - - @func my_uuid2str() - @param guid uuid - @param s Output buffer.Must be at least MY_UUID_STRING_LENGTH+1 large. -*/ -void my_uuid2str(const uchar *guid, char *s) -{ - int i; - for (i=0; i < MY_UUID_SIZE; i++) - { - *s++= _dig_vec_lower[guid[i] >>4]; - *s++= _dig_vec_lower[guid[i] & 15]; - if(i == 3 || i == 5 || i == 7 || i == 9) - *s++= '-'; - } -} - -void my_uuid_end() -{ - if (my_uuid_inited) - { - my_uuid_inited= 0; - pthread_mutex_destroy(&LOCK_uuid_generator); - } -} |