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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 18:07:14 +0000 |
commit | a175314c3e5827eb193872241446f2f8f5c9d33c (patch) | |
tree | cd3d60ca99ae00829c52a6ca79150a5b6e62528b /sql/tztime.cc | |
parent | Initial commit. (diff) | |
download | mariadb-10.5-upstream.tar.xz mariadb-10.5-upstream.zip |
Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sql/tztime.cc')
-rw-r--r-- | sql/tztime.cc | 3029 |
1 files changed, 3029 insertions, 0 deletions
diff --git a/sql/tztime.cc b/sql/tztime.cc new file mode 100644 index 00000000..23c015e4 --- /dev/null +++ b/sql/tztime.cc @@ -0,0 +1,3029 @@ +/* + Copyright (c) 2004, 2010, Oracle and/or its affiliates. + + 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +/* + Most of the following code and structures were derived from + public domain code from ftp://elsie.nci.nih.gov/pub + (We will refer to this code as to elsie-code further.) +*/ + +/* + We should not include sql_priv.h in mysql_tzinfo_to_sql utility since + it creates unsolved link dependencies on some platforms. +*/ + +#ifdef USE_PRAGMA_IMPLEMENTATION +#pragma implementation // gcc: Class implementation +#endif + +#include "mariadb.h" +#if !defined(TZINFO2SQL) && !defined(TESTTIME) +#include "sql_priv.h" +#include "unireg.h" +#include "sql_time.h" // localtime_to_TIME +#include "sql_base.h" // open_system_tables_for_read, + // close_system_tables +#else +#include <my_time.h> +#include <my_sys.h> +#include <mysql_version.h> +#include <my_getopt.h> +#endif + +#include "tztime.h" +#include "tzfile.h" +#include <m_string.h> +#include <my_dir.h> +#include <mysql/psi/mysql_file.h> +#include "lock.h" // MYSQL_LOCK_IGNORE_FLUSH, + // MYSQL_LOCK_IGNORE_TIMEOUT + +/* + Now we don't use abbreviations in server but we will do this in future. +*/ +#if defined(TZINFO2SQL) || defined(TESTTIME) +#define ABBR_ARE_USED +#else +#if !defined(DBUG_OFF) +/* Let use abbreviations for debug purposes */ +#undef ABBR_ARE_USED +#define ABBR_ARE_USED +#endif /* !defined(DBUG_OFF) */ +#endif /* defined(TZINFO2SQL) || defined(TESTTIME) */ + +#define PROGRAM_VERSION "1.1" + +/* Structure describing local time type (e.g. Moscow summer time (MSD)) */ +typedef struct ttinfo +{ + long tt_gmtoff; // Offset from UTC in seconds + uint tt_isdst; // Is daylight saving time or not. Used to set tm_isdst +#ifdef ABBR_ARE_USED + uint tt_abbrind; // Index of start of abbreviation for this time type. +#endif + /* + We don't use tt_ttisstd and tt_ttisgmt members of original elsie-code + struct since we don't support POSIX-style TZ descriptions in variables. + */ +} TRAN_TYPE_INFO; + +/* Structure describing leap-second corrections. */ +typedef struct lsinfo +{ + my_time_t ls_trans; // Transition time + long ls_corr; // Correction to apply +} LS_INFO; + +/* + Structure with information describing ranges of my_time_t shifted to local + time (my_time_t + offset). Used for local MYSQL_TIME -> my_time_t conversion. + See comments for TIME_to_gmt_sec() for more info. +*/ +typedef struct revtinfo +{ + long rt_offset; // Offset of local time from UTC in seconds + uint rt_type; // Type of period 0 - Normal period. 1 - Spring time-gap +} REVT_INFO; + +#ifdef TZNAME_MAX +#define MY_TZNAME_MAX TZNAME_MAX +#endif +#ifndef TZNAME_MAX +#define MY_TZNAME_MAX 255 +#endif + +/* + Structure which fully describes time zone which is + described in our db or in zoneinfo files. +*/ +typedef struct st_time_zone_info +{ + uint leapcnt; // Number of leap-second corrections + uint timecnt; // Number of transitions between time types + uint typecnt; // Number of local time types + uint charcnt; // Number of characters used for abbreviations + uint revcnt; // Number of transition descr. for TIME->my_time_t conversion + /* The following are dynamical arrays are allocated in MEM_ROOT */ + my_time_t *ats; // Times of transitions between time types + uchar *types; // Local time types for transitions + TRAN_TYPE_INFO *ttis; // Local time types descriptions +#ifdef ABBR_ARE_USED + /* Storage for local time types abbreviations. They are stored as ASCIIZ */ + char *chars; +#endif + /* + Leap seconds corrections descriptions, this array is shared by + all time zones who use leap seconds. + */ + LS_INFO *lsis; + /* + Starting points and descriptions of shifted my_time_t (my_time_t + offset) + ranges on which shifted my_time_t -> my_time_t mapping is linear or undefined. + Used for tm -> my_time_t conversion. + */ + my_time_t *revts; + REVT_INFO *revtis; + /* + Time type which is used for times smaller than first transition or if + there are no transitions at all. + */ + TRAN_TYPE_INFO *fallback_tti; + +} TIME_ZONE_INFO; + + +static my_bool prepare_tz_info(TIME_ZONE_INFO *sp, MEM_ROOT *storage); + +my_bool opt_leap, opt_verbose, opt_skip_write_binlog; + +#if defined(TZINFO2SQL) || defined(TESTTIME) + +/* + Load time zone description from zoneinfo (TZinfo) file. + + SYNOPSIS + tz_load() + name - path to zoneinfo file + sp - TIME_ZONE_INFO structure to fill + + RETURN VALUES + 0 - Ok + 1 - Error +*/ +static my_bool +tz_load(const char *name, TIME_ZONE_INFO *sp, MEM_ROOT *storage) +{ + uchar *p; + ssize_t read_from_file; + uint i; + MYSQL_FILE *file; + + if (!(file= mysql_file_fopen(0, name, O_RDONLY|O_BINARY, MYF(MY_WME)))) + return 1; + { + union + { + struct tzhead tzhead; + uchar buf[sizeof(struct tzhead) + sizeof(my_time_t) * TZ_MAX_TIMES + + TZ_MAX_TIMES + sizeof(TRAN_TYPE_INFO) * TZ_MAX_TYPES + +#ifdef ABBR_ARE_USED + MY_MAX(TZ_MAX_CHARS + 1, (2 * (MY_TZNAME_MAX + 1))) + +#endif + sizeof(LS_INFO) * TZ_MAX_LEAPS]; + } u; + uint ttisstdcnt; + uint ttisgmtcnt; + char *tzinfo_buf; + + read_from_file= (ssize_t)mysql_file_fread(file, u.buf, sizeof(u.buf), MYF(MY_WME)); + + if (mysql_file_fclose(file, MYF(MY_WME)) != 0) + return 1; + + if (read_from_file < (int)sizeof(struct tzhead)) + return 1; + + ttisstdcnt= int4net(u.tzhead.tzh_ttisgmtcnt); + ttisgmtcnt= int4net(u.tzhead.tzh_ttisstdcnt); + sp->leapcnt= int4net(u.tzhead.tzh_leapcnt); + sp->timecnt= int4net(u.tzhead.tzh_timecnt); + sp->typecnt= int4net(u.tzhead.tzh_typecnt); + sp->charcnt= int4net(u.tzhead.tzh_charcnt); + p= u.tzhead.tzh_charcnt + sizeof(u.tzhead.tzh_charcnt); + if (sp->leapcnt > TZ_MAX_LEAPS || + sp->typecnt == 0 || sp->typecnt > TZ_MAX_TYPES || + sp->timecnt > TZ_MAX_TIMES || + sp->charcnt > TZ_MAX_CHARS || + (ttisstdcnt != sp->typecnt && ttisstdcnt != 0) || + (ttisgmtcnt != sp->typecnt && ttisgmtcnt != 0)) + return 1; + if ((uint)(read_from_file - (p - u.buf)) < + sp->timecnt * 4 + /* ats */ + sp->timecnt + /* types */ + sp->typecnt * (4 + 2) + /* ttinfos */ + sp->charcnt + /* chars */ + sp->leapcnt * (4 + 4) + /* lsinfos */ + ttisstdcnt + /* ttisstds */ + ttisgmtcnt) /* ttisgmts */ + return 1; + + if (!(tzinfo_buf= (char *)alloc_root(storage, + ALIGN_SIZE(sp->timecnt * + sizeof(my_time_t)) + + ALIGN_SIZE(sp->timecnt) + + ALIGN_SIZE(sp->typecnt * + sizeof(TRAN_TYPE_INFO)) + +#ifdef ABBR_ARE_USED + ALIGN_SIZE(sp->charcnt+1) + +#endif + sp->leapcnt * sizeof(LS_INFO)))) + return 1; + + sp->ats= (my_time_t *)tzinfo_buf; + tzinfo_buf+= ALIGN_SIZE(sp->timecnt * sizeof(my_time_t)); + sp->types= (uchar *)tzinfo_buf; + tzinfo_buf+= ALIGN_SIZE(sp->timecnt); + sp->ttis= (TRAN_TYPE_INFO *)tzinfo_buf; + tzinfo_buf+= ALIGN_SIZE(sp->typecnt * sizeof(TRAN_TYPE_INFO)); +#ifdef ABBR_ARE_USED + sp->chars= tzinfo_buf; + tzinfo_buf+= ALIGN_SIZE(sp->charcnt+1); +#endif + sp->lsis= (LS_INFO *)tzinfo_buf; + + for (i= 0; i < sp->timecnt; i++, p+= 4) + sp->ats[i]= int4net(p); + + for (i= 0; i < sp->timecnt; i++) + { + sp->types[i]= (uchar) *p++; + if (sp->types[i] >= sp->typecnt) + return 1; + } + for (i= 0; i < sp->typecnt; i++) + { + TRAN_TYPE_INFO * ttisp; + + ttisp= &sp->ttis[i]; + ttisp->tt_gmtoff= int4net(p); + p+= 4; + ttisp->tt_isdst= (uchar) *p++; + if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1) + return 1; + ttisp->tt_abbrind= (uchar) *p++; + if (ttisp->tt_abbrind > sp->charcnt) + return 1; + } + for (i= 0; i < sp->charcnt; i++) + sp->chars[i]= *p++; + sp->chars[i]= '\0'; /* ensure '\0' at end */ + for (i= 0; i < sp->leapcnt; i++) + { + LS_INFO *lsisp; + + lsisp= &sp->lsis[i]; + lsisp->ls_trans= int4net(p); + p+= 4; + lsisp->ls_corr= int4net(p); + p+= 4; + } + /* + Since we don't support POSIX style TZ definitions in variables we + don't read further like glibc or elsie code. + */ + } + + return prepare_tz_info(sp, storage); +} +#endif /* defined(TZINFO2SQL) || defined(TESTTIME) */ + + +/* + Finish preparation of time zone description for use in TIME_to_gmt_sec() + and gmt_sec_to_TIME() functions. + + SYNOPSIS + prepare_tz_info() + sp - pointer to time zone description + storage - pointer to MEM_ROOT where arrays for map allocated + + DESCRIPTION + First task of this function is to find fallback time type which will + be used if there are no transitions or we have moment in time before + any transitions. + Second task is to build "shifted my_time_t" -> my_time_t map used in + MYSQL_TIME -> my_time_t conversion. + Note: See description of TIME_to_gmt_sec() function first. + In order to perform MYSQL_TIME -> my_time_t conversion we need to build table + which defines "shifted by tz offset and leap seconds my_time_t" -> + my_time_t function which is almost the same (except ranges of ambiguity) + as reverse function to piecewise linear function used for my_time_t -> + "shifted my_time_t" conversion and which is also specified as table in + zoneinfo file or in our db (It is specified as start of time type ranges + and time type offsets). So basic idea is very simple - let us iterate + through my_time_t space from one point of discontinuity of my_time_t -> + "shifted my_time_t" function to another and build our approximation of + reverse function. (Actually we iterate through ranges on which + my_time_t -> "shifted my_time_t" is linear function). + + RETURN VALUES + 0 Ok + 1 Error +*/ +static my_bool +prepare_tz_info(TIME_ZONE_INFO *sp, MEM_ROOT *storage) +{ + my_time_t cur_t= MY_TIME_T_MIN; + my_time_t cur_l, end_t, UNINIT_VAR(end_l); + my_time_t cur_max_seen_l= MY_TIME_T_MIN; + long cur_offset, cur_corr, cur_off_and_corr; + uint next_trans_idx, next_leap_idx; + uint i; + /* + Temporary arrays where we will store tables. Needed because + we don't know table sizes ahead. (Well we can estimate their + upper bound but this will take extra space.) + */ + my_time_t revts[TZ_MAX_REV_RANGES]; + REVT_INFO revtis[TZ_MAX_REV_RANGES]; + + /* + Let us setup fallback time type which will be used if we have not any + transitions or if we have moment of time before first transition. + We will find first non-DST local time type and use it (or use first + local time type if all of them are DST types). + */ + for (i= 0; i < sp->typecnt && sp->ttis[i].tt_isdst; i++) + /* no-op */ ; + if (i == sp->typecnt) + i= 0; + sp->fallback_tti= &(sp->ttis[i]); + + + /* + Let us build shifted my_time_t -> my_time_t map. + */ + sp->revcnt= 0; + + /* Let us find initial offset */ + if (sp->timecnt == 0 || cur_t < sp->ats[0]) + { + /* + If we have not any transitions or t is before first transition we are using + already found fallback time type which index is already in i. + */ + next_trans_idx= 0; + } + else + { + /* cur_t == sp->ats[0] so we found transition */ + i= sp->types[0]; + next_trans_idx= 1; + } + + cur_offset= sp->ttis[i].tt_gmtoff; + + + /* let us find leap correction... unprobable, but... */ + for (next_leap_idx= 0; next_leap_idx < sp->leapcnt && + cur_t >= sp->lsis[next_leap_idx].ls_trans; + ++next_leap_idx) + continue; + + if (next_leap_idx > 0) + cur_corr= sp->lsis[next_leap_idx - 1].ls_corr; + else + cur_corr= 0; + + /* Iterate trough t space */ + while (sp->revcnt < TZ_MAX_REV_RANGES - 1) + { + cur_off_and_corr= cur_offset - cur_corr; + + /* + We assuming that cur_t could be only overflowed downwards, + we also assume that end_t won't be overflowed in this case. + */ + if (cur_off_and_corr < 0 && + cur_t < MY_TIME_T_MIN - cur_off_and_corr) + cur_t= MY_TIME_T_MIN - cur_off_and_corr; + + cur_l= cur_t + cur_off_and_corr; + + /* + Let us choose end_t as point before next time type change or leap + second correction. + */ + end_t= MY_MIN((next_trans_idx < sp->timecnt) ? sp->ats[next_trans_idx] - 1: + MY_TIME_T_MAX, + (next_leap_idx < sp->leapcnt) ? + sp->lsis[next_leap_idx].ls_trans - 1: MY_TIME_T_MAX); + /* + again assuming that end_t can be overlowed only in positive side + we also assume that end_t won't be overflowed in this case. + */ + if (cur_off_and_corr > 0 && + end_t > MY_TIME_T_MAX - cur_off_and_corr) + end_t= MY_TIME_T_MAX - cur_off_and_corr; + + end_l= end_t + cur_off_and_corr; + + + if (end_l > cur_max_seen_l) + { + /* We want special handling in the case of first range */ + if (cur_max_seen_l == MY_TIME_T_MIN) + { + revts[sp->revcnt]= cur_l; + revtis[sp->revcnt].rt_offset= cur_off_and_corr; + revtis[sp->revcnt].rt_type= 0; + sp->revcnt++; + cur_max_seen_l= end_l; + } + else + { + if (cur_l > cur_max_seen_l + 1) + { + /* We have a spring time-gap and we are not at the first range */ + revts[sp->revcnt]= cur_max_seen_l + 1; + revtis[sp->revcnt].rt_offset= revtis[sp->revcnt-1].rt_offset; + revtis[sp->revcnt].rt_type= 1; + sp->revcnt++; + if (sp->revcnt == TZ_MAX_TIMES + TZ_MAX_LEAPS + 1) + break; /* That was too much */ + cur_max_seen_l= cur_l - 1; + } + + /* Assume here end_l > cur_max_seen_l (because end_l>=cur_l) */ + + revts[sp->revcnt]= cur_max_seen_l + 1; + revtis[sp->revcnt].rt_offset= cur_off_and_corr; + revtis[sp->revcnt].rt_type= 0; + sp->revcnt++; + cur_max_seen_l= end_l; + } + } + + if (end_t == MY_TIME_T_MAX || + ((cur_off_and_corr > 0) && + (end_t >= MY_TIME_T_MAX - cur_off_and_corr))) + /* end of t space */ + break; + + cur_t= end_t + 1; + + /* + Let us find new offset and correction. Because of our choice of end_t + cur_t can only be point where new time type starts or/and leap + correction is performed. + */ + if (sp->timecnt != 0 && cur_t >= sp->ats[0]) /* else reuse old offset */ + if (next_trans_idx < sp->timecnt && + cur_t == sp->ats[next_trans_idx]) + { + /* We are at offset point */ + cur_offset= sp->ttis[sp->types[next_trans_idx]].tt_gmtoff; + ++next_trans_idx; + } + + if (next_leap_idx < sp->leapcnt && + cur_t == sp->lsis[next_leap_idx].ls_trans) + { + /* we are at leap point */ + cur_corr= sp->lsis[next_leap_idx].ls_corr; + ++next_leap_idx; + } + } + + /* check if we have had enough space */ + if (sp->revcnt == TZ_MAX_REV_RANGES - 1) + return 1; + + /* set maximum end_l as finisher */ + revts[sp->revcnt]= end_l; + + /* Allocate arrays of proper size in sp and copy result there */ + if (!(sp->revts= (my_time_t *)alloc_root(storage, + sizeof(my_time_t) * (sp->revcnt + 1))) || + !(sp->revtis= (REVT_INFO *)alloc_root(storage, + sizeof(REVT_INFO) * sp->revcnt))) + return 1; + + memcpy(sp->revts, revts, sizeof(my_time_t) * (sp->revcnt + 1)); + memcpy(sp->revtis, revtis, sizeof(REVT_INFO) * sp->revcnt); + + return 0; +} + + +#if !defined(TZINFO2SQL) + +static const uint mon_lengths[2][MONS_PER_YEAR]= +{ + { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }, + { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 } +}; + +static const uint mon_starts[2][MONS_PER_YEAR]= +{ + { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }, + { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335 } +}; + +static const uint year_lengths[2]= +{ + DAYS_PER_NYEAR, DAYS_PER_LYEAR +}; + +#define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) + + +/* + Converts time from my_time_t representation (seconds in UTC since Epoch) + to broken down representation using given local time zone offset. + + SYNOPSIS + sec_to_TIME() + tmp - pointer to structure for broken down representation + t - my_time_t value to be converted + offset - local time zone offset + + DESCRIPTION + Convert my_time_t with offset to MYSQL_TIME struct. Differs from timesub + (from elsie code) because doesn't contain any leap correction and + TM_GMTOFF and is_dst setting and contains some MySQL specific + initialization. Funny but with removing of these we almost have + glibc's offtime function. +*/ +static void +sec_to_TIME(MYSQL_TIME * tmp, my_time_t t, long offset) +{ + long days; + long rem; + int y; + int yleap; + const uint *ip; + + days= (long) (t / SECS_PER_DAY); + rem= (long) (t % SECS_PER_DAY); + + /* + We do this as separate step after dividing t, because this + allows us handle times near my_time_t bounds without overflows. + */ + rem+= offset; + while (rem < 0) + { + rem+= SECS_PER_DAY; + days--; + } + while (rem >= SECS_PER_DAY) + { + rem -= SECS_PER_DAY; + days++; + } + tmp->hour= (uint)(rem / SECS_PER_HOUR); + rem= rem % SECS_PER_HOUR; + tmp->minute= (uint)(rem / SECS_PER_MIN); + /* + A positive leap second requires a special + representation. This uses "... ??:59:60" et seq. + */ + tmp->second= (uint)(rem % SECS_PER_MIN); + + y= EPOCH_YEAR; + while (days < 0 || days >= (long)year_lengths[yleap= isleap(y)]) + { + int newy; + + newy= y + days / DAYS_PER_NYEAR; + if (days < 0) + newy--; + days-= (newy - y) * DAYS_PER_NYEAR + + LEAPS_THRU_END_OF(newy - 1) - + LEAPS_THRU_END_OF(y - 1); + y= newy; + } + tmp->year= y; + + ip= mon_lengths[yleap]; + for (tmp->month= 0; days >= (long) ip[tmp->month]; tmp->month++) + days= days - (long) ip[tmp->month]; + tmp->month++; + tmp->day= (uint)(days + 1); + + /* filling MySQL specific MYSQL_TIME members */ + tmp->neg= 0; tmp->second_part= 0; + tmp->time_type= MYSQL_TIMESTAMP_DATETIME; +} + + +/* + Find time range which contains given my_time_t value + + SYNOPSIS + find_time_range() + t - my_time_t value for which we looking for range + range_boundaries - sorted array of range starts. + higher_bound - number of ranges + + DESCRIPTION + Performs binary search for range which contains given my_time_t value. + It has sense if number of ranges is greater than zero and my_time_t value + is greater or equal than beginning of first range. It also assumes that + t belongs to some range specified or end of last is MY_TIME_T_MAX. + + With this localtime_r on real data may takes less time than with linear + search (I've seen 30% speed up). + + RETURN VALUE + Index of range to which t belongs +*/ +static uint +find_time_range(my_time_t t, const my_time_t *range_boundaries, + uint higher_bound) +{ + uint i, lower_bound= 0; + + /* + Function will work without this assertion but result would be meaningless. + */ + DBUG_ASSERT(higher_bound > 0 && t >= range_boundaries[0]); + + /* + Do binary search for minimal interval which contain t. We preserve: + range_boundaries[lower_bound] <= t < range_boundaries[higher_bound] + invariant and decrease this higher_bound - lower_bound gap twice + times on each step. + */ + + while (higher_bound - lower_bound > 1) + { + i= (lower_bound + higher_bound) >> 1; + if (range_boundaries[i] <= t) + lower_bound= i; + else + higher_bound= i; + } + return lower_bound; +} + +/* + Find local time transition for given my_time_t. + + SYNOPSIS + find_transition_type() + t - my_time_t value to be converted + sp - pointer to struct with time zone description + + RETURN VALUE + Pointer to structure in time zone description describing + local time type for given my_time_t. +*/ +static +const TRAN_TYPE_INFO * +find_transition_type(my_time_t t, const TIME_ZONE_INFO *sp) +{ + if (unlikely(sp->timecnt == 0 || t < sp->ats[0])) + { + /* + If we have not any transitions or t is before first transition let + us use fallback time type. + */ + return sp->fallback_tti; + } + + /* + Do binary search for minimal interval between transitions which + contain t. With this localtime_r on real data may takes less + time than with linear search (I've seen 30% speed up). + */ + return &(sp->ttis[sp->types[find_time_range(t, sp->ats, sp->timecnt)]]); +} + + +/* + Converts time in my_time_t representation (seconds in UTC since Epoch) to + broken down MYSQL_TIME representation in local time zone. + + SYNOPSIS + gmt_sec_to_TIME() + tmp - pointer to structure for broken down represenatation + sec_in_utc - my_time_t value to be converted + sp - pointer to struct with time zone description + + TODO + We can improve this function by creating joined array of transitions and + leap corrections. This will require adding extra field to TRAN_TYPE_INFO + for storing number of "extra" seconds to minute occurred due to correction + (60th and 61st second, look how we calculate them as "hit" in this + function). + Under realistic assumptions about frequency of transitions the same array + can be used fot MYSQL_TIME -> my_time_t conversion. For this we need to + implement tweaked binary search which will take into account that some + MYSQL_TIME has two matching my_time_t ranges and some of them have none. +*/ +static void +gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t sec_in_utc, const TIME_ZONE_INFO *sp) +{ + const TRAN_TYPE_INFO *ttisp; + const LS_INFO *lp; + long corr= 0; + int hit= 0; + int i; + + /* + Find proper transition (and its local time type) for our sec_in_utc value. + Funny but again by separating this step in function we receive code + which very close to glibc's code. No wonder since they obviously use + the same base and all steps are sensible. + */ + ttisp= find_transition_type(sec_in_utc, sp); + + /* + Let us find leap correction for our sec_in_utc value and number of extra + secs to add to this minute. + This loop is rarely used because most users will use time zones without + leap seconds, and even in case when we have such time zone there won't + be many iterations (we have about 22 corrections at this moment (2004)). + */ + for ( i= sp->leapcnt; i-- > 0; ) + { + lp= &sp->lsis[i]; + if (sec_in_utc >= lp->ls_trans) + { + if (sec_in_utc == lp->ls_trans) + { + hit= ((i == 0 && lp->ls_corr > 0) || + lp->ls_corr > sp->lsis[i - 1].ls_corr); + if (hit) + { + while (i > 0 && + sp->lsis[i].ls_trans == sp->lsis[i - 1].ls_trans + 1 && + sp->lsis[i].ls_corr == sp->lsis[i - 1].ls_corr + 1) + { + hit++; + i--; + } + } + } + corr= lp->ls_corr; + break; + } + } + + sec_to_TIME(tmp, sec_in_utc, ttisp->tt_gmtoff - corr); + + tmp->second+= hit; +} + + +/* + Converts local time in broken down representation to local + time zone analog of my_time_t represenation. + + SYNOPSIS + sec_since_epoch() + year, mon, mday, hour, min, sec - broken down representation. + + DESCRIPTION + Converts time in broken down representation to my_time_t representation + ignoring time zone. Note that we cannot convert back some valid _local_ + times near ends of my_time_t range because of my_time_t overflow. But we + ignore this fact now since MySQL will never pass such argument. + + RETURN VALUE + Seconds since epoch time representation. +*/ +static my_time_t +sec_since_epoch(int year, int mon, int mday, int hour, int min ,int sec) +{ + /* Guard against my_time_t overflow(on system with 32 bit my_time_t) */ + DBUG_ASSERT(!(year == TIMESTAMP_MAX_YEAR && mon == 1 && mday > 17)); +#ifndef WE_WANT_TO_HANDLE_UNORMALIZED_DATES + /* + It turns out that only whenever month is normalized or unnormalized + plays role. + */ + DBUG_ASSERT(mon > 0 && mon < 13); + long days= year * DAYS_PER_NYEAR - EPOCH_YEAR * DAYS_PER_NYEAR + + LEAPS_THRU_END_OF(year - 1) - + LEAPS_THRU_END_OF(EPOCH_YEAR - 1); + days+= mon_starts[isleap(year)][mon - 1]; +#else + long norm_month= (mon - 1) % MONS_PER_YEAR; + long a_year= year + (mon - 1)/MONS_PER_YEAR - (int)(norm_month < 0); + long days= a_year * DAYS_PER_NYEAR - EPOCH_YEAR * DAYS_PER_NYEAR + + LEAPS_THRU_END_OF(a_year - 1) - + LEAPS_THRU_END_OF(EPOCH_YEAR - 1); + days+= mon_starts[isleap(a_year)] + [norm_month + (norm_month < 0 ? MONS_PER_YEAR : 0)]; +#endif + days+= mday - 1; + + return ((days * HOURS_PER_DAY + hour) * MINS_PER_HOUR + min) * + SECS_PER_MIN + sec; +} + +/* + Converts local time in broken down MYSQL_TIME representation to my_time_t + representation. + + SYNOPSIS + TIME_to_gmt_sec() + t - pointer to structure for broken down represenatation + sp - pointer to struct with time zone description + error_code - 0, if the conversion was successful; + ER_WARN_DATA_OUT_OF_RANGE, if t contains datetime value + which is out of TIMESTAMP range; + ER_WARN_INVALID_TIMESTAMP, if t represents value which + doesn't exists (falls into the spring time-gap). + + DESCRIPTION + This is mktime analog for MySQL. It is essentially different + from mktime (or hypotetical my_mktime) because: + - It has no idea about tm_isdst member so if it + has two answers it will give the smaller one + - If we are in spring time gap then it will return + beginning of the gap + - It can give wrong results near the ends of my_time_t due to + overflows, but we are safe since in MySQL we will never + call this function for such dates (its restriction for year + between 1970 and 2038 gives us several days of reserve). + - By default it doesn't support un-normalized input. But if + sec_since_epoch() function supports un-normalized dates + then this function should handle un-normalized input right, + altough it won't normalize structure TIME. + + Traditional approach to problem of conversion from broken down + representation to time_t is iterative. Both elsie's and glibc + implementation try to guess what time_t value should correspond to + this broken-down value. They perform localtime_r function on their + guessed value and then calculate the difference and try to improve + their guess. Elsie's code guesses time_t value in bit by bit manner, + Glibc's code tries to add difference between broken-down value + corresponding to guess and target broken-down value to current guess. + It also uses caching of last found correction... So Glibc's approach + is essentially faster but introduces some undetermenism (in case if + is_dst member of broken-down representation (tm struct) is not known + and we have two possible answers). + + We use completely different approach. It is better since it is both + faster than iterative implementations and fully determenistic. If you + look at my_time_t to MYSQL_TIME conversion then you'll find that it consist + of two steps: + The first is calculating shifted my_time_t value and the second - TIME + calculation from shifted my_time_t value (well it is a bit simplified + picture). The part in which we are interested in is my_time_t -> shifted + my_time_t conversion. It is piecewise linear function which is defined + by combination of transition times as break points and times offset + as changing function parameter. The possible inverse function for this + converison would be ambiguos but with MySQL's restrictions we can use + some function which is the same as inverse function on unambigiuos + ranges and coincides with one of branches of inverse function in + other ranges. Thus we just need to build table which will determine + this shifted my_time_t -> my_time_t conversion similar to existing + (my_time_t -> shifted my_time_t table). We do this in + prepare_tz_info function. + + TODO + If we can even more improve this function. For doing this we will need to + build joined map of transitions and leap corrections for gmt_sec_to_TIME() + function (similar to revts/revtis). Under realistic assumptions about + frequency of transitions we can use the same array for TIME_to_gmt_sec(). + We need to implement special version of binary search for this. Such step + will be beneficial to CPU cache since we will decrease data-set used for + conversion twice. + + RETURN VALUE + Seconds in UTC since Epoch. + 0 in case of error. +*/ + +static my_time_t +TIME_to_gmt_sec(const MYSQL_TIME *t, const TIME_ZONE_INFO *sp, uint *error_code) +{ + my_time_t local_t; + uint saved_seconds; + uint i; + int shift= 0; + DBUG_ENTER("TIME_to_gmt_sec"); + + if (!validate_timestamp_range(t)) + { + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + DBUG_RETURN(0); + } + + *error_code= 0; + + /* We need this for correct leap seconds handling */ + if (t->second < SECS_PER_MIN) + saved_seconds= 0; + else + saved_seconds= t->second; + + /* + NOTE: to convert full my_time_t range we do a shift of the + boundary dates here to avoid overflow of my_time_t. + We use alike approach in my_system_gmt_sec(). + + However in that function we also have to take into account + overflow near 0 on some platforms. That's because my_system_gmt_sec + uses localtime_r(), which doesn't work with negative values correctly + on platforms with unsigned time_t (QNX). Here we don't use localtime() + => we negative values of local_t are ok. + */ + + if ((t->year == TIMESTAMP_MAX_YEAR) && (t->month == 1) && t->day > 4) + { + /* + We will pass (t->day - shift) to sec_since_epoch(), and + want this value to be a positive number, so we shift + only dates > 4.01.2038 (to avoid owerflow). + */ + shift= 2; + } + + + local_t= sec_since_epoch(t->year, t->month, (t->day - shift), + t->hour, t->minute, + saved_seconds ? 0 : t->second); + + /* We have at least one range */ + DBUG_ASSERT(sp->revcnt >= 1); + + if (local_t < sp->revts[0] || local_t > sp->revts[sp->revcnt]) + { + /* + This means that source time can't be represented as my_time_t due to + limited my_time_t range. + */ + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + DBUG_RETURN(0); + } + + /* binary search for our range */ + i= find_time_range(local_t, sp->revts, sp->revcnt); + + /* + As there are no offset switches at the end of TIMESTAMP range, + we could simply check for overflow here (and don't need to bother + about DST gaps etc) + */ + if (shift) + { + if (local_t > (my_time_t) (TIMESTAMP_MAX_VALUE - shift * SECS_PER_DAY + + sp->revtis[i].rt_offset - saved_seconds)) + { + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + DBUG_RETURN(0); /* my_time_t overflow */ + } + local_t+= shift * SECS_PER_DAY; + } + + if (sp->revtis[i].rt_type) + { + /* + Oops! We are in spring time gap. + May be we should return error here? + Now we are returning my_time_t value corresponding to the + beginning of the gap. + */ + *error_code= ER_WARN_INVALID_TIMESTAMP; + local_t= sp->revts[i] - sp->revtis[i].rt_offset + saved_seconds; + } + else + local_t= local_t - sp->revtis[i].rt_offset + saved_seconds; + + /* check for TIMESTAMP_MAX_VALUE was already done above */ + if (local_t < TIMESTAMP_MIN_VALUE) + { + local_t= 0; + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + } + + DBUG_RETURN(local_t); +} + + +/* + End of elsie derived code. +*/ +#endif /* !defined(TZINFO2SQL) */ + + +#if !defined(TESTTIME) && !defined(TZINFO2SQL) + +/* + String with names of SYSTEM time zone. +*/ +static const String tz_SYSTEM_name("SYSTEM", 6, &my_charset_latin1); + + +/* + Instance of this class represents local time zone used on this system + (specified by TZ environment variable or via any other system mechanism). + It uses system functions (localtime_r, my_system_gmt_sec) for conversion + and is always available. Because of this it is used by default - if there + were no explicit time zone specified. On the other hand because of this + conversion methods provided by this class is significantly slower and + possibly less multi-threaded-friendly than corresponding Time_zone_db + methods so the latter should be preffered there it is possible. +*/ +class Time_zone_system : public Time_zone +{ +public: + Time_zone_system() {} /* Remove gcc warning */ + virtual my_time_t TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const; + virtual void gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const; + virtual const String * get_name() const; +}; + + +/* + Converts local time in system time zone in MYSQL_TIME representation + to its my_time_t representation. + + SYNOPSIS + TIME_to_gmt_sec() + t - pointer to MYSQL_TIME structure with local time in + broken-down representation. + error_code - 0, if the conversion was successful; + ER_WARN_DATA_OUT_OF_RANGE, if t contains datetime value + which is out of TIMESTAMP range; + ER_WARN_INVALID_TIMESTAMP, if t represents value which + doesn't exists (falls into the spring time-gap). + + DESCRIPTION + This method uses system function (localtime_r()) for conversion + local time in system time zone in MYSQL_TIME structure to its my_time_t + representation. Unlike the same function for Time_zone_db class + it it won't handle unnormalized input properly. Still it will + return lowest possible my_time_t in case of ambiguity or if we + provide time corresponding to the time-gap. + + You should call my_init_time() function before using this function. + + RETURN VALUE + Corresponding my_time_t value or 0 in case of error +*/ +my_time_t +Time_zone_system::TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const +{ + long not_used; + return my_system_gmt_sec(t, ¬_used, error_code); +} + + +/* + Converts time from UTC seconds since Epoch (my_time_t) representation + to system local time zone broken-down representation. + + SYNOPSIS + gmt_sec_to_TIME() + tmp - pointer to MYSQL_TIME structure to fill-in + t - my_time_t value to be converted + + NOTE + We assume that value passed to this function will fit into time_t range + supported by localtime_r. This conversion is putting restriction on + TIMESTAMP range in MySQL. If we can get rid of SYSTEM time zone at least + for interaction with client then we can extend TIMESTAMP range down to + the 1902 easily. +*/ +void +Time_zone_system::gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const +{ + struct tm tmp_tm; + time_t tmp_t= (time_t)t; + + localtime_r(&tmp_t, &tmp_tm); + localtime_to_TIME(tmp, &tmp_tm); + tmp->time_type= MYSQL_TIMESTAMP_DATETIME; + adjust_leap_second(tmp); +} + + +/* + Get name of time zone + + SYNOPSIS + get_name() + + RETURN VALUE + Name of time zone as String +*/ +const String * +Time_zone_system::get_name() const +{ + return &tz_SYSTEM_name; +} + + +/* + Instance of this class represents UTC time zone. It uses system gmtime_r + function for conversions and is always available. It is used only for + my_time_t -> MYSQL_TIME conversions in various UTC_... functions, it is not + intended for MYSQL_TIME -> my_time_t conversions and shouldn't be exposed to user. +*/ +class Time_zone_utc : public Time_zone +{ +public: + Time_zone_utc() {} /* Remove gcc warning */ + virtual my_time_t TIME_to_gmt_sec(const MYSQL_TIME *t, + uint *error_code) const; + virtual void gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const; + virtual const String * get_name() const; +}; + + +/* + Convert UTC time from MYSQL_TIME representation to its my_time_t representation. + + DESCRIPTION + Since Time_zone_utc is used only internally for my_time_t -> TIME + conversions, this function of Time_zone interface is not implemented for + this class and should not be called. + + RETURN VALUE + 0 +*/ +my_time_t +Time_zone_utc::TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const +{ + /* Should be never called */ + DBUG_ASSERT(0); + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + return 0; +} + + +/* + Converts time from UTC seconds since Epoch (my_time_t) representation + to broken-down representation (also in UTC). + + SYNOPSIS + gmt_sec_to_TIME() + tmp - pointer to MYSQL_TIME structure to fill-in + t - my_time_t value to be converted + + NOTE + See note for apropriate Time_zone_system method. +*/ +void +Time_zone_utc::gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const +{ + struct tm tmp_tm; + time_t tmp_t= (time_t)t; + gmtime_r(&tmp_t, &tmp_tm); + localtime_to_TIME(tmp, &tmp_tm); + tmp->time_type= MYSQL_TIMESTAMP_DATETIME; + adjust_leap_second(tmp); +} + + +/* + Get name of time zone + + SYNOPSIS + get_name() + + DESCRIPTION + Since Time_zone_utc is used only internally by SQL's UTC_* functions it + is not accessible directly, and hence this function of Time_zone + interface is not implemented for this class and should not be called. + + RETURN VALUE + 0 +*/ +const String * +Time_zone_utc::get_name() const +{ + /* Should be never called */ + DBUG_ASSERT(0); + return 0; +} + + +/* + Instance of this class represents some time zone which is + described in mysql.time_zone family of tables. +*/ +class Time_zone_db : public Time_zone +{ +public: + Time_zone_db(TIME_ZONE_INFO *tz_info_arg, const String * tz_name_arg); + virtual my_time_t TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const; + virtual void gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const; + virtual const String * get_name() const; +private: + TIME_ZONE_INFO *tz_info; + const String *tz_name; +}; + + +/* + Initializes object representing time zone described by mysql.time_zone + tables. + + SYNOPSIS + Time_zone_db() + tz_info_arg - pointer to TIME_ZONE_INFO structure which is filled + according to db or other time zone description + (for example by my_tz_init()). + Several Time_zone_db instances can share one + TIME_ZONE_INFO structure. + tz_name_arg - name of time zone. +*/ +Time_zone_db::Time_zone_db(TIME_ZONE_INFO *tz_info_arg, + const String *tz_name_arg): + tz_info(tz_info_arg), tz_name(tz_name_arg) +{ +} + + +/* + Converts local time in time zone described from TIME + representation to its my_time_t representation. + + SYNOPSIS + TIME_to_gmt_sec() + t - pointer to MYSQL_TIME structure with local time + in broken-down representation. + error_code - 0, if the conversion was successful; + ER_WARN_DATA_OUT_OF_RANGE, if t contains datetime value + which is out of TIMESTAMP range; + ER_WARN_INVALID_TIMESTAMP, if t represents value which + doesn't exists (falls into the spring time-gap). + + DESCRIPTION + Please see ::TIME_to_gmt_sec for function description and + parameter restrictions. + + RETURN VALUE + Corresponding my_time_t value or 0 in case of error +*/ +my_time_t +Time_zone_db::TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const +{ + return ::TIME_to_gmt_sec(t, tz_info, error_code); +} + + +/* + Converts time from UTC seconds since Epoch (my_time_t) representation + to local time zone described in broken-down representation. + + SYNOPSIS + gmt_sec_to_TIME() + tmp - pointer to MYSQL_TIME structure to fill-in + t - my_time_t value to be converted +*/ +void +Time_zone_db::gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const +{ + ::gmt_sec_to_TIME(tmp, t, tz_info); + adjust_leap_second(tmp); +} + + +/* + Get name of time zone + + SYNOPSIS + get_name() + + RETURN VALUE + Name of time zone as ASCIIZ-string +*/ +const String * +Time_zone_db::get_name() const +{ + return tz_name; +} + + +/* + Instance of this class represents time zone which + was specified as offset from UTC. +*/ +class Time_zone_offset : public Time_zone +{ +public: + Time_zone_offset(long tz_offset_arg); + virtual my_time_t TIME_to_gmt_sec(const MYSQL_TIME *t, + uint *error_code) const; + virtual void gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const; + virtual const String * get_name() const; + /* + This have to be public because we want to be able to access it from + my_offset_tzs_get_key() function + */ + long offset; +private: + /* Extra reserve because of snprintf */ + char name_buff[7+16]; + String name; +}; + + +/* + Initializes object representing time zone described by its offset from UTC. + + SYNOPSIS + Time_zone_offset() + tz_offset_arg - offset from UTC in seconds. + Positive for direction to east. +*/ +Time_zone_offset::Time_zone_offset(long tz_offset_arg): + offset(tz_offset_arg) +{ + uint hours= abs((int)(offset / SECS_PER_HOUR)); + uint minutes= abs((int)(offset % SECS_PER_HOUR / SECS_PER_MIN)); + size_t length= my_snprintf(name_buff, sizeof(name_buff), "%s%02d:%02d", + (offset>=0) ? "+" : "-", hours, minutes); + name.set(name_buff, length, &my_charset_latin1); +} + + +/* + Converts local time in time zone described as offset from UTC + from MYSQL_TIME representation to its my_time_t representation. + + SYNOPSIS + TIME_to_gmt_sec() + t - pointer to MYSQL_TIME structure with local time + in broken-down representation. + error_code - 0, if the conversion was successful; + ER_WARN_DATA_OUT_OF_RANGE, if t contains datetime value + which is out of TIMESTAMP range; + ER_WARN_INVALID_TIMESTAMP, if t represents value which + doesn't exists (falls into the spring time-gap). + + RETURN VALUE + Corresponding my_time_t value or 0 in case of error. +*/ + +my_time_t +Time_zone_offset::TIME_to_gmt_sec(const MYSQL_TIME *t, uint *error_code) const +{ + my_time_t local_t; + int shift= 0; + + /* + Check timestamp range.we have to do this as calling function relies on + us to make all validation checks here. + */ + if (!validate_timestamp_range(t)) + { + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + return 0; + } + *error_code= 0; + + /* + Do a temporary shift of the boundary dates to avoid + overflow of my_time_t if the time value is near it's + maximum range + */ + if ((t->year == TIMESTAMP_MAX_YEAR) && (t->month == 1) && t->day > 4) + shift= 2; + + local_t= sec_since_epoch(t->year, t->month, (t->day - shift), + t->hour, t->minute, t->second) - + offset; + + if (shift) + { + /* Add back the shifted time */ + local_t+= shift * SECS_PER_DAY; + } + + if (local_t >= TIMESTAMP_MIN_VALUE && local_t <= TIMESTAMP_MAX_VALUE) + return local_t; + + /* range error*/ + *error_code= ER_WARN_DATA_OUT_OF_RANGE; + return 0; +} + + +/* + Converts time from UTC seconds since Epoch (my_time_t) representation + to local time zone described as offset from UTC and in broken-down + representation. + + SYNOPSIS + gmt_sec_to_TIME() + tmp - pointer to MYSQL_TIME structure to fill-in + t - my_time_t value to be converted +*/ +void +Time_zone_offset::gmt_sec_to_TIME(MYSQL_TIME *tmp, my_time_t t) const +{ + sec_to_TIME(tmp, t, offset); +} + + +/* + Get name of time zone + + SYNOPSIS + get_name() + + RETURN VALUE + Name of time zone as pointer to String object +*/ +const String * +Time_zone_offset::get_name() const +{ + return &name; +} + + +static Time_zone_utc tz_UTC; +static Time_zone_system tz_SYSTEM; +static Time_zone_offset tz_OFFSET0(0); + +Time_zone *my_tz_OFFSET0= &tz_OFFSET0; +Time_zone *my_tz_UTC= &tz_UTC; +Time_zone *my_tz_SYSTEM= &tz_SYSTEM; + +static HASH tz_names; +static HASH offset_tzs; +static MEM_ROOT tz_storage; + +/* + These mutex protects offset_tzs and tz_storage. + These protection needed only when we are trying to set + time zone which is specified as offset, and searching for existing + time zone in offset_tzs or creating if it didn't existed before in + tz_storage. So contention is low. +*/ +static mysql_mutex_t tz_LOCK; +static bool tz_inited= 0; + +/* + This two static variables are inteded for holding info about leap seconds + shared by all time zones. +*/ +static uint tz_leapcnt= 0; +static LS_INFO *tz_lsis= 0; + +/* + Shows whenever we have found time zone tables during start-up. + Used for avoiding of putting those tables to global table list + for queries that use time zone info. +*/ +static bool time_zone_tables_exist= 1; + + +/* + Names of tables (with their lengths) that are needed + for dynamical loading of time zone descriptions. +*/ + +static const LEX_CSTRING tz_tables_names[MY_TZ_TABLES_COUNT]= +{ + { STRING_WITH_LEN("time_zone_name")}, + { STRING_WITH_LEN("time_zone")}, + { STRING_WITH_LEN("time_zone_transition_type")}, + { STRING_WITH_LEN("time_zone_transition")} +}; + +class Tz_names_entry: public Sql_alloc +{ +public: + String name; + Time_zone *tz; +}; + + +/* + We are going to call both of these functions from C code so + they should obey C calling conventions. +*/ + +extern "C" uchar * +my_tz_names_get_key(Tz_names_entry *entry, size_t *length, + my_bool not_used __attribute__((unused))) +{ + *length= entry->name.length(); + return (uchar*) entry->name.ptr(); +} + +extern "C" uchar * +my_offset_tzs_get_key(Time_zone_offset *entry, + size_t *length, + my_bool not_used __attribute__((unused))) +{ + *length= sizeof(long); + return (uchar*) &entry->offset; +} + + +/* + Prepare table list with time zone related tables from preallocated array. + + SYNOPSIS + tz_init_table_list() + tz_tabs - pointer to preallocated array of MY_TZ_TABLES_COUNT + TABLE_LIST objects + + DESCRIPTION + This function prepares list of TABLE_LIST objects which can be used + for opening of time zone tables from preallocated array. +*/ + +static void +tz_init_table_list(TABLE_LIST *tz_tabs) +{ + for (int i= 0; i < MY_TZ_TABLES_COUNT; i++) + { + tz_tabs[i].init_one_table(&MYSQL_SCHEMA_NAME, tz_tables_names + i, + NULL, TL_READ); + if (i != MY_TZ_TABLES_COUNT - 1) + tz_tabs[i].next_global= tz_tabs[i].next_local= &tz_tabs[i+1]; + if (i != 0) + tz_tabs[i].prev_global= &tz_tabs[i-1].next_global; + } +} + +static PSI_memory_key key_memory_tz_storage; + +#ifdef HAVE_PSI_INTERFACE +static PSI_mutex_key key_tz_LOCK; + +static PSI_mutex_info all_tz_mutexes[]= +{ + { & key_tz_LOCK, "tz_LOCK", PSI_FLAG_GLOBAL} +}; + +static PSI_memory_info all_tz_memory[]= +{ + { &key_memory_tz_storage, "tz_storage", PSI_FLAG_GLOBAL} +}; + +static void init_tz_psi_keys(void) +{ + const char* category= "sql"; + int count; + + if (PSI_server == NULL) + return; + + count= array_elements(all_tz_mutexes); + PSI_server->register_mutex(category, all_tz_mutexes, count); + + count= array_elements(all_tz_memory); + mysql_memory_register(category, all_tz_memory, count); +} +#endif /* HAVE_PSI_INTERFACE */ + + +/* + Initialize time zone support infrastructure. + + SYNOPSIS + my_tz_init() + thd - current thread object + default_tzname - default time zone or 0 if none. + bootstrap - indicates whenever we are in bootstrap mode + + DESCRIPTION + This function will init memory structures needed for time zone support, + it will register mandatory SYSTEM time zone in them. It will try to open + mysql.time_zone* tables and load information about default time zone and + information which further will be shared among all time zones loaded. + If system tables with time zone descriptions don't exist it won't fail + (unless default_tzname is time zone from tables). If bootstrap parameter + is true then this routine assumes that we are in bootstrap mode and won't + load time zone descriptions unless someone specifies default time zone + which is supposedly stored in those tables. + It'll also set default time zone if it is specified. + + RETURN VALUES + 0 - ok + 1 - Error +*/ +my_bool +my_tz_init(THD *org_thd, const char *default_tzname, my_bool bootstrap) +{ + THD *thd; + TABLE_LIST tz_tables[1+MY_TZ_TABLES_COUNT]; + TABLE *table; + const LEX_CSTRING tmp_table_name= { STRING_WITH_LEN("time_zone_leap_second") }; + Tz_names_entry *tmp_tzname; + my_bool return_val= 1; + int res; + DBUG_ENTER("my_tz_init"); + +#ifdef HAVE_PSI_INTERFACE + init_tz_psi_keys(); +#endif + + /* + To be able to run this from boot, we allocate a temporary THD + */ + if (!(thd= new THD(0))) + DBUG_RETURN(1); + thd->thread_stack= (char*) &thd; + thd->store_globals(); + + /* Init all memory structures that require explicit destruction */ + if (my_hash_init(key_memory_tz_storage, &tz_names, &my_charset_latin1, 20, 0, + 0, (my_hash_get_key) my_tz_names_get_key, 0, 0)) + { + sql_print_error("Fatal error: OOM while initializing time zones"); + goto end; + } + if (my_hash_init(key_memory_tz_storage, &offset_tzs, &my_charset_latin1, 26, + 0, 0, (my_hash_get_key)my_offset_tzs_get_key, 0, 0)) + { + sql_print_error("Fatal error: OOM while initializing time zones"); + my_hash_free(&tz_names); + goto end; + } + init_sql_alloc(key_memory_tz_storage, &tz_storage, 32 * 1024, 0, MYF(0)); + mysql_mutex_init(key_tz_LOCK, &tz_LOCK, MY_MUTEX_INIT_FAST); + tz_inited= 1; + + /* Add 'SYSTEM' time zone to tz_names hash */ + if (!(tmp_tzname= new (&tz_storage) Tz_names_entry())) + { + sql_print_error("Fatal error: OOM while initializing time zones"); + goto end_with_cleanup; + } + tmp_tzname->name.set(STRING_WITH_LEN("SYSTEM"), &my_charset_latin1); + tmp_tzname->tz= my_tz_SYSTEM; + if (my_hash_insert(&tz_names, (const uchar *)tmp_tzname)) + { + sql_print_error("Fatal error: OOM while initializing time zones"); + goto end_with_cleanup; + } + + if (bootstrap) + { + /* If we are in bootstrap mode we should not load time zone tables */ + return_val= time_zone_tables_exist= 0; + goto end_with_cleanup; + } + + /* + After this point all memory structures are inited and we even can live + without time zone description tables. Now try to load information about + leap seconds shared by all time zones. + */ + + thd->set_db(&MYSQL_SCHEMA_NAME); + bzero((char*) &tz_tables[0], sizeof(TABLE_LIST)); + tz_tables[0].alias= tz_tables[0].table_name= tmp_table_name; + tz_tables[0].db= MYSQL_SCHEMA_NAME; + tz_tables[0].lock_type= TL_READ; + + tz_init_table_list(tz_tables+1); + tz_tables[0].next_global= tz_tables[0].next_local= &tz_tables[1]; + tz_tables[1].prev_global= &tz_tables[0].next_global; + init_mdl_requests(tz_tables); + + /* + We need to open only mysql.time_zone_leap_second, but we try to + open all time zone tables to see if they exist. + */ + if (open_and_lock_tables(thd, tz_tables, FALSE, + MYSQL_OPEN_IGNORE_FLUSH | MYSQL_LOCK_IGNORE_TIMEOUT)) + { + sql_print_warning("Can't open and lock time zone table: %s " + "trying to live without them", + thd->get_stmt_da()->message()); + /* We will try emulate that everything is ok */ + return_val= time_zone_tables_exist= 0; + goto end_with_setting_default_tz; + } + + for (TABLE_LIST *tl= tz_tables; tl; tl= tl->next_global) + { + tl->table->use_all_columns(); + /* Force close at the end of the function to free memory. */ + tl->table->mark_table_for_reopen(); + } + + /* + Now we are going to load leap seconds descriptions that are shared + between all time zones that use them. We are using index for getting + records in proper order. Since we share the same MEM_ROOT between + all time zones we just allocate enough memory for it first. + */ + if (!(tz_lsis= (LS_INFO*) alloc_root(&tz_storage, + sizeof(LS_INFO) * TZ_MAX_LEAPS))) + { + sql_print_error("Fatal error: Out of memory while loading " + "mysql.time_zone_leap_second table"); + goto end_with_close; + } + + table= tz_tables[0].table; + + if (table->file->ha_index_init(0, 1)) + goto end_with_close; + + table->use_all_columns(); + tz_leapcnt= 0; + + res= table->file->ha_index_first(table->record[0]); + + while (!res) + { + if (tz_leapcnt + 1 > TZ_MAX_LEAPS) + { + sql_print_error("Fatal error: While loading mysql.time_zone_leap_second" + " table: too much leaps"); + table->file->ha_index_end(); + goto end_with_close; + } + + tz_lsis[tz_leapcnt].ls_trans= (my_time_t)table->field[0]->val_int(); + tz_lsis[tz_leapcnt].ls_corr= (long)table->field[1]->val_int(); + + tz_leapcnt++; + + DBUG_PRINT("info", + ("time_zone_leap_second table: tz_leapcnt: %u tt_time: %lu offset: %ld", + tz_leapcnt, (ulong) tz_lsis[tz_leapcnt-1].ls_trans, + tz_lsis[tz_leapcnt-1].ls_corr)); + + res= table->file->ha_index_next(table->record[0]); + } + + (void)table->file->ha_index_end(); + + if (res != HA_ERR_END_OF_FILE) + { + sql_print_error("Fatal error: Error while loading " + "mysql.time_zone_leap_second table"); + goto end_with_close; + } + + /* + Loading of info about leap seconds succeeded + */ + + return_val= 0; + + +end_with_setting_default_tz: + /* If we have default time zone try to load it */ + if (default_tzname) + { + String tmp_tzname2(default_tzname, &my_charset_latin1); + /* + Time zone tables may be open here, and my_tz_find() may open + most of them once more, but this is OK for system tables open + for READ. + */ + if (unlikely(!(global_system_variables.time_zone= + my_tz_find(thd, &tmp_tzname2)))) + { + sql_print_error("Fatal error: Illegal or unknown default time zone '%s'", + default_tzname); + return_val= 1; + } + } + +end_with_close: + if (time_zone_tables_exist) + close_mysql_tables(thd); + +end_with_cleanup: + + /* if there were error free time zone describing structs */ + if (unlikely(return_val)) + my_tz_free(); +end: + delete thd; + if (org_thd) + org_thd->store_globals(); /* purecov: inspected */ + + default_tz= default_tz_name ? global_system_variables.time_zone + : my_tz_SYSTEM; + + DBUG_RETURN(return_val); +} + + +/* + Free resources used by time zone support infrastructure. + + SYNOPSIS + my_tz_free() +*/ + +void my_tz_free() +{ + if (tz_inited) + { + tz_inited= 0; + mysql_mutex_destroy(&tz_LOCK); + my_hash_free(&offset_tzs); + my_hash_free(&tz_names); + free_root(&tz_storage, MYF(0)); + } +} + + +/* + Load time zone description from system tables. + + SYNOPSIS + tz_load_from_open_tables() + tz_name - name of time zone that should be loaded. + tz_tables - list of tables from which time zone description + should be loaded + + DESCRIPTION + This function will try to load information about time zone specified + from the list of the already opened and locked tables (first table in + tz_tables should be time_zone_name, next time_zone, then + time_zone_transition_type and time_zone_transition should be last). + It will also update information in hash used for time zones lookup. + + RETURN VALUES + Returns pointer to newly created Time_zone object or 0 in case of error. + +*/ + +static Time_zone* +tz_load_from_open_tables(const String *tz_name, TABLE_LIST *tz_tables) +{ + TABLE *table= 0; + TIME_ZONE_INFO *tz_info= NULL; + Tz_names_entry *tmp_tzname; + Time_zone *return_val= 0; + int res; + uint tzid, ttid; + my_time_t ttime; + char buff[MAX_FIELD_WIDTH]; + uchar keybuff[32]; + Field *field; + String abbr(buff, sizeof(buff), &my_charset_latin1); + char *alloc_buff= NULL; + char *tz_name_buff= NULL; + /* + Temporary arrays that are used for loading of data for filling + TIME_ZONE_INFO structure + */ + my_time_t ats[TZ_MAX_TIMES]; + uchar types[TZ_MAX_TIMES]; + TRAN_TYPE_INFO ttis[TZ_MAX_TYPES]; +#ifdef ABBR_ARE_USED + char chars[MY_MAX(TZ_MAX_CHARS + 1, (2 * (MY_TZNAME_MAX + 1)))]; +#endif + /* + Used as a temporary tz_info until we decide that we actually want to + allocate and keep the tz info and tz name in tz_storage. + */ + TIME_ZONE_INFO tmp_tz_info; + memset(&tmp_tz_info, 0, sizeof(TIME_ZONE_INFO)); + + DBUG_ENTER("tz_load_from_open_tables"); + + /* + Let us find out time zone id by its name (there is only one index + and it is specifically for this purpose). + */ + table= tz_tables->table; + tz_tables= tz_tables->next_local; + table->field[0]->store(tz_name->ptr(), tz_name->length(), + &my_charset_latin1); + if (table->file->ha_index_init(0, 1)) + goto end; + + if (table->file->ha_index_read_map(table->record[0], table->field[0]->ptr, + HA_WHOLE_KEY, HA_READ_KEY_EXACT)) + { +#ifdef EXTRA_DEBUG + /* + Most probably user has mistyped time zone name, so no need to bark here + unless we need it for debugging. + */ + sql_print_error("Can't find description of time zone '%.*b'", + tz_name->length(), tz_name->ptr()); +#endif + goto end; + } + + tzid= (uint)table->field[1]->val_int(); + + (void)table->file->ha_index_end(); + + /* + Now we need to lookup record in mysql.time_zone table in order to + understand whenever this timezone uses leap seconds (again we are + using the only index in this table). + */ + table= tz_tables->table; + tz_tables= tz_tables->next_local; + field= table->field[0]; + field->store((longlong) tzid, TRUE); + DBUG_ASSERT(field->key_length() <= sizeof(keybuff)); + field->get_key_image(keybuff, + MY_MIN(field->key_length(), sizeof(keybuff)), + Field::itRAW); + if (table->file->ha_index_init(0, 1)) + goto end; + + if (table->file->ha_index_read_map(table->record[0], keybuff, + HA_WHOLE_KEY, HA_READ_KEY_EXACT)) + { + sql_print_error("Can't find description of time zone '%u'", tzid); + goto end; + } + + /* If Uses_leap_seconds == 'Y' */ + if (table->field[1]->val_int() == 1) + { + tmp_tz_info.leapcnt= tz_leapcnt; + tmp_tz_info.lsis= tz_lsis; + } + + (void)table->file->ha_index_end(); + + /* + Now we will iterate through records for out time zone in + mysql.time_zone_transition_type table. Because we want records + only for our time zone guess what are we doing? + Right - using special index. + */ + table= tz_tables->table; + tz_tables= tz_tables->next_local; + field= table->field[0]; + field->store((longlong) tzid, TRUE); + DBUG_ASSERT(field->key_length() <= sizeof(keybuff)); + field->get_key_image(keybuff, + MY_MIN(field->key_length(), sizeof(keybuff)), + Field::itRAW); + if (table->file->ha_index_init(0, 1)) + goto end; + + res= table->file->ha_index_read_map(table->record[0], keybuff, + (key_part_map)1, HA_READ_KEY_EXACT); + while (!res) + { + ttid= (uint)table->field[1]->val_int(); + + if (ttid >= TZ_MAX_TYPES) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition_type table: too big " + "transition type id"); + goto end; + } + + ttis[ttid].tt_gmtoff= (long)table->field[2]->val_int(); + ttis[ttid].tt_isdst= (table->field[3]->val_int() > 0); + +#ifdef ABBR_ARE_USED + // FIXME should we do something with duplicates here ? + table->field[4]->val_str(&abbr, &abbr); + if (tmp_tz_info.charcnt + abbr.length() + 1 > sizeof(chars)) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition_type table: not enough " + "room for abbreviations"); + goto end; + } + ttis[ttid].tt_abbrind= tmp_tz_info.charcnt; + memcpy(chars + tmp_tz_info.charcnt, abbr.ptr(), abbr.length()); + tmp_tz_info.charcnt+= abbr.length(); + chars[tmp_tz_info.charcnt]= 0; + tmp_tz_info.charcnt++; + + DBUG_PRINT("info", + ("time_zone_transition_type table: tz_id=%u tt_id=%u tt_gmtoff=%ld " + "abbr='%s' tt_isdst=%u", tzid, ttid, ttis[ttid].tt_gmtoff, + chars + ttis[ttid].tt_abbrind, ttis[ttid].tt_isdst)); +#else + DBUG_PRINT("info", + ("time_zone_transition_type table: tz_id=%u tt_id=%u tt_gmtoff=%ld " + "tt_isdst=%u", tzid, ttid, ttis[ttid].tt_gmtoff, ttis[ttid].tt_isdst)); +#endif + + /* ttid is increasing because we are reading using index */ + DBUG_ASSERT(ttid >= tmp_tz_info.typecnt); + + tmp_tz_info.typecnt= ttid + 1; + + res= table->file->ha_index_next_same(table->record[0], keybuff, 4); + } + + if (res != HA_ERR_END_OF_FILE) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition_type table"); + goto end; + } + + (void)table->file->ha_index_end(); + + + /* + At last we are doing the same thing for records in + mysql.time_zone_transition table. Here we additionally need records + in ascending order by index scan also satisfies us. + */ + table= tz_tables->table; + table->field[0]->store((longlong) tzid, TRUE); + if (table->file->ha_index_init(0, 1)) + goto end; + + res= table->file->ha_index_read_map(table->record[0], keybuff, + (key_part_map)1, HA_READ_KEY_EXACT); + while (!res) + { + ttime= (my_time_t)table->field[1]->val_int(); + ttid= (uint)table->field[2]->val_int(); + + if (tmp_tz_info.timecnt + 1 > TZ_MAX_TIMES) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition table: " + "too much transitions"); + goto end; + } + if (ttid + 1 > tmp_tz_info.typecnt) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition table: " + "bad transition type id"); + goto end; + } + + ats[tmp_tz_info.timecnt]= ttime; + types[tmp_tz_info.timecnt]= ttid; + tmp_tz_info.timecnt++; + + DBUG_PRINT("info", + ("time_zone_transition table: tz_id: %u tt_time: %lu tt_id: %u", + tzid, (ulong) ttime, ttid)); + + res= table->file->ha_index_next_same(table->record[0], keybuff, 4); + } + + /* + We have to allow HA_ERR_KEY_NOT_FOUND because some time zones + for example UTC have no transitons. + */ + if (res != HA_ERR_END_OF_FILE && res != HA_ERR_KEY_NOT_FOUND) + { + sql_print_error("Error while loading time zone description from " + "mysql.time_zone_transition table"); + goto end; + } + + (void)table->file->ha_index_end(); + table= 0; + + /* + Let us check how correct our time zone description is. We don't check for + tz->timecnt < 1 since it is ok for GMT. + */ + if (tmp_tz_info.typecnt < 1) + { + sql_print_error("loading time zone without transition types"); + goto end; + } + + /* Allocate memory for the timezone info and timezone name in tz_storage. */ + if (!(alloc_buff= (char*) alloc_root(&tz_storage, sizeof(TIME_ZONE_INFO) + + tz_name->length() + 1))) + { + sql_print_error("Out of memory while loading time zone description"); + return 0; + } + + /* Move the temporary tz_info into the allocated area */ + tz_info= (TIME_ZONE_INFO *)alloc_buff; + memcpy(tz_info, &tmp_tz_info, sizeof(TIME_ZONE_INFO)); + tz_name_buff= alloc_buff + sizeof(TIME_ZONE_INFO); + /* + By writing zero to the end we guarantee that we can call ptr() + instead of c_ptr() for time zone name. + */ + strmake(tz_name_buff, tz_name->ptr(), tz_name->length()); + + /* + Now we will allocate memory and init TIME_ZONE_INFO structure. + */ + if (!(alloc_buff= (char*) alloc_root(&tz_storage, + ALIGN_SIZE(sizeof(my_time_t) * + tz_info->timecnt) + + ALIGN_SIZE(tz_info->timecnt) + +#ifdef ABBR_ARE_USED + ALIGN_SIZE(tz_info->charcnt) + +#endif + sizeof(TRAN_TYPE_INFO) * + tz_info->typecnt))) + { + sql_print_error("Out of memory while loading time zone description"); + goto end; + } + + tz_info->ats= (my_time_t *) alloc_buff; + memcpy(tz_info->ats, ats, tz_info->timecnt * sizeof(my_time_t)); + alloc_buff+= ALIGN_SIZE(sizeof(my_time_t) * tz_info->timecnt); + tz_info->types= (uchar *)alloc_buff; + memcpy(tz_info->types, types, tz_info->timecnt); + alloc_buff+= ALIGN_SIZE(tz_info->timecnt); +#ifdef ABBR_ARE_USED + tz_info->chars= alloc_buff; + memcpy(tz_info->chars, chars, tz_info->charcnt); + alloc_buff+= ALIGN_SIZE(tz_info->charcnt); +#endif + tz_info->ttis= (TRAN_TYPE_INFO *)alloc_buff; + memcpy(tz_info->ttis, ttis, tz_info->typecnt * sizeof(TRAN_TYPE_INFO)); + + /* Build reversed map. */ + if (prepare_tz_info(tz_info, &tz_storage)) + { + sql_print_error("Unable to build mktime map for time zone"); + goto end; + } + + + if (!(tmp_tzname= new (&tz_storage) Tz_names_entry()) || + !(tmp_tzname->tz= new (&tz_storage) Time_zone_db(tz_info, + &(tmp_tzname->name))) || + (tmp_tzname->name.set(tz_name_buff, tz_name->length(), + &my_charset_latin1), + my_hash_insert(&tz_names, (const uchar *)tmp_tzname))) + { + sql_print_error("Out of memory while loading time zone"); + goto end; + } + + /* + Loading of time zone succeeded + */ + return_val= tmp_tzname->tz; + +end: + + if (table && table->file->inited) + (void) table->file->ha_index_end(); + + DBUG_RETURN(return_val); +} + + +/* + Parse string that specifies time zone as offset from UTC. + + SYNOPSIS + str_to_offset() + str - pointer to string which contains offset + length - length of string + offset - out parameter for storing found offset in seconds. + + DESCRIPTION + This function parses string which contains time zone offset + in form similar to '+10:00' and converts found value to + seconds from UTC form (east is positive). + + RETURN VALUE + 0 - Ok + 1 - String doesn't contain valid time zone offset +*/ +my_bool +str_to_offset(const char *str, uint length, long *offset) +{ + const char *end= str + length; + my_bool negative; + ulong number_tmp; + long offset_tmp; + + if (length < 4) + return 1; + + if (*str == '+') + negative= 0; + else if (*str == '-') + negative= 1; + else + return 1; + str++; + + number_tmp= 0; + + while (str < end && my_isdigit(&my_charset_latin1, *str)) + { + number_tmp= number_tmp*10 + *str - '0'; + str++; + } + + if (str + 1 >= end || *str != ':') + return 1; + str++; + + offset_tmp = number_tmp * MINS_PER_HOUR; number_tmp= 0; + + while (str < end && my_isdigit(&my_charset_latin1, *str)) + { + number_tmp= number_tmp * 10 + *str - '0'; + str++; + } + + if (str != end) + return 1; + + offset_tmp= (offset_tmp + number_tmp) * SECS_PER_MIN; + + if (negative) + offset_tmp= -offset_tmp; + + /* + Check if offset is in range prescribed by standard + (from -12:59 to 13:00). + */ + + if (number_tmp > 59 || offset_tmp < -13 * SECS_PER_HOUR + 1 || + offset_tmp > 13 * SECS_PER_HOUR) + return 1; + + *offset= offset_tmp; + + return 0; +} + + +/* + Get Time_zone object for specified time zone. + + SYNOPSIS + my_tz_find() + thd - pointer to thread THD structure + name - time zone specification + + DESCRIPTION + This function checks if name is one of time zones described in db, + predefined SYSTEM time zone or valid time zone specification as + offset from UTC (In last case it will create proper Time_zone_offset + object if there were not any.). If name is ok it returns corresponding + Time_zone object. + + Clients of this function are not responsible for releasing resources + occupied by returned Time_zone object so they can just forget pointers + to Time_zone object if they are not needed longer. + + Other important property of this function: if some Time_zone found once + it will be for sure found later, so this function can also be used for + checking if proper Time_zone object exists (and if there will be error + it will be reported during first call). + + If name pointer is 0 then this function returns 0 (this allows to pass 0 + values as parameter without additional external check and this property + is used by @@time_zone variable handling code). + + It will perform lookup in system tables (mysql.time_zone*), + opening and locking them, and closing afterwards. It won't perform + such lookup if no time zone describing tables were found during + server start up. + + RETURN VALUE + Pointer to corresponding Time_zone object. 0 - in case of bad time zone + specification or other error. + +*/ +Time_zone * +my_tz_find(THD *thd, const String *name) +{ + Tz_names_entry *tmp_tzname; + Time_zone *result_tz= 0; + long offset; + DBUG_ENTER("my_tz_find"); + DBUG_PRINT("enter", ("time zone name='%s'", + name ? ((String *)name)->c_ptr_safe() : "NULL")); + + if (!name || name->is_empty()) + DBUG_RETURN(0); + + mysql_mutex_lock(&tz_LOCK); + + if (!str_to_offset(name->ptr(), name->length(), &offset)) + { + if (!(result_tz= (Time_zone_offset *)my_hash_search(&offset_tzs, + (const uchar *)&offset, + sizeof(long)))) + { + DBUG_PRINT("info", ("Creating new Time_zone_offset object")); + + if (!(result_tz= new (&tz_storage) Time_zone_offset(offset)) || + my_hash_insert(&offset_tzs, (const uchar *) result_tz)) + { + result_tz= 0; + sql_print_error("Fatal error: Out of memory " + "while setting new time zone"); + } + } + } + else + { + result_tz= 0; + if ((tmp_tzname= (Tz_names_entry *)my_hash_search(&tz_names, + (const uchar *) + name->ptr(), + name->length()))) + result_tz= tmp_tzname->tz; + else if (time_zone_tables_exist) + { + TABLE_LIST tz_tables[MY_TZ_TABLES_COUNT]; + + /* + Allocate start_new_trans with malloc as it's > 4000 bytes and this + function can be called deep inside a stored procedure + */ + start_new_trans *new_trans= new start_new_trans(thd); + tz_init_table_list(tz_tables); + init_mdl_requests(tz_tables); + if (!open_system_tables_for_read(thd, tz_tables)) + { + result_tz= tz_load_from_open_tables(name, tz_tables); + thd->commit_whole_transaction_and_close_tables(); + } + new_trans->restore_old_transaction(); + delete new_trans; + } + } + + mysql_mutex_unlock(&tz_LOCK); + + if (result_tz && result_tz != my_tz_SYSTEM && result_tz != my_tz_UTC) + status_var_increment(thd->status_var.feature_timezone); + + DBUG_RETURN(result_tz); +} + + +/** + Convert leap seconds into non-leap + + This function will convert the leap seconds added by the OS to + non-leap seconds, e.g. 23:59:59, 23:59:60 -> 23:59:59, 00:00:01 ... + This check is not checking for years on purpose : although it's not a + complete check this way it doesn't require looking (and having installed) + the leap seconds table. + + @param[in,out] broken down time structure as filled in by the OS +*/ + +void Time_zone::adjust_leap_second(MYSQL_TIME *t) +{ + if (t->second == 60 || t->second == 61) + t->second= 59; +} + +#endif /* !defined(TESTTIME) && !defined(TZINFO2SQL) */ + + +#ifdef TZINFO2SQL +/* + This code belongs to mysql_tzinfo_to_sql converter command line utility. + This utility should be used by db admin for populating mysql.time_zone + tables. +*/ + +/* + Print info about time zone described by TIME_ZONE_INFO struct as + SQL statements populating mysql.time_zone* tables. + + SYNOPSIS + print_tz_as_sql() + tz_name - name of time zone + sp - structure describing time zone +*/ +void +print_tz_as_sql(const char* tz_name, const TIME_ZONE_INFO *sp) +{ + uint i; + + /* Here we assume that all time zones have same leap correction tables */ + printf("INSERT INTO time_zone (Use_leap_seconds) VALUES ('%s');\n", + sp->leapcnt ? "Y" : "N"); + printf("SET @time_zone_id= LAST_INSERT_ID();\n"); + printf("INSERT INTO time_zone_name (Name, Time_zone_id) VALUES \ +('%s', @time_zone_id);\n", tz_name); + + if (sp->timecnt) + { + printf("INSERT INTO time_zone_transition \ +(Time_zone_id, Transition_time, Transition_type_id) VALUES\n"); + for (i= 0; i < sp->timecnt; i++) + printf("%s(@time_zone_id, %ld, %u)\n", (i == 0 ? " " : ","), sp->ats[i], + (uint)sp->types[i]); + printf(";\n"); + } + + printf("INSERT INTO time_zone_transition_type \ +(Time_zone_id, Transition_type_id, Offset, Is_DST, Abbreviation) VALUES\n"); + + for (i= 0; i < sp->typecnt; i++) + printf("%s(@time_zone_id, %u, %ld, %d, '%s')\n", (i == 0 ? " " : ","), i, + sp->ttis[i].tt_gmtoff, sp->ttis[i].tt_isdst, + sp->chars + sp->ttis[i].tt_abbrind); + printf(";\n"); +} + + +/* + Print info about leap seconds in time zone as SQL statements + populating mysql.time_zone_leap_second table. + + SYNOPSIS + print_tz_leaps_as_sql() + sp - structure describing time zone +*/ +void +print_tz_leaps_as_sql(const TIME_ZONE_INFO *sp) +{ + uint i; + + /* + We are assuming that there are only one list of leap seconds + For all timezones. + */ + if (!opt_skip_write_binlog) + printf("\\d |\n" + "IF (select count(*) from information_schema.global_variables where\n" + "variable_name='wsrep_on' and variable_value='ON') = 1 THEN\n" + "ALTER TABLE time_zone_leap_second ENGINE=InnoDB;\n" + "END IF|\n" + "\\d ;\n"); + + printf("TRUNCATE TABLE time_zone_leap_second;\n"); + + if (sp->leapcnt) + { + printf("INSERT INTO time_zone_leap_second \ +(Transition_time, Correction) VALUES\n"); + for (i= 0; i < sp->leapcnt; i++) + printf("%s(%ld, %ld)\n", (i == 0 ? " " : ","), + sp->lsis[i].ls_trans, sp->lsis[i].ls_corr); + printf(";\n"); + } + + if (!opt_skip_write_binlog) + printf("\\d |\n" + "IF (select count(*) from information_schema.global_variables where\n" + "variable_name='wsrep_on' and variable_value='ON') = 1 THEN\n" + "ALTER TABLE time_zone_leap_second ENGINE=Aria;\n" + "END IF|\n" + "\\d ;\n"); + + printf("ALTER TABLE time_zone_leap_second ORDER BY Transition_time;\n"); +} + + +/* + Some variables used as temporary or as parameters + in recursive scan_tz_dir() code. +*/ +TIME_ZONE_INFO tz_info; +MEM_ROOT tz_storage; +char fullname[FN_REFLEN + 1]; +char *root_name_end; + +/* + known file types that exist in the zoneinfo directory that are safe to + silently skip +*/ +const char *known_extensions[]= { + ".tab", + NullS +}; + + +/* + Recursively scan zoneinfo directory and print all found time zone + descriptions as SQL. + + SYNOPSIS + scan_tz_dir() + name_end - pointer to end of path to directory to be searched. + symlink_recursion_level How many symlink directory levels are used + verbose >0 if we should print warnings + + DESCRIPTION + This auxiliary recursive function also uses several global + variables as in parameters and for storing temporary values. + + fullname - path to directory that should be scanned. + root_name_end - pointer to place in fullname where part with + path to initial directory ends. + current_tz_id - last used time zone id + + RETURN VALUE + 0 - Ok, 1 - Fatal error + +*/ +my_bool +scan_tz_dir(char * name_end, uint symlink_recursion_level, uint verbose) +{ + MY_DIR *cur_dir; + char *name_end_tmp; + uint i; + + /* Sort directory data, to pass mtr tests on different platforms. */ + if (!(cur_dir= my_dir(fullname, MYF(MY_WANT_STAT|MY_WANT_SORT)))) + return 1; + + name_end= strmake(name_end, "/", FN_REFLEN - (name_end - fullname)); + + for (i= 0; i < cur_dir->number_of_files; i++) + { + if (cur_dir->dir_entry[i].name[0] != '.' && + strcmp(cur_dir->dir_entry[i].name, "Factory")) + { + name_end_tmp= strmake(name_end, cur_dir->dir_entry[i].name, + FN_REFLEN - (name_end - fullname)); + + if (MY_S_ISDIR(cur_dir->dir_entry[i].mystat->st_mode)) + { + my_bool is_symlink; + if ((is_symlink= my_is_symlink(fullname)) && + symlink_recursion_level > 0) + { + /* + The timezone definition data in some Linux distributions + (e.g. the "timezone-data-2013f" package in Gentoo) + may have synlimks like: + /usr/share/zoneinfo/posix/ -> /usr/share/zoneinfo/, + so the same timezone files are available under two names + (e.g. "CET" and "posix/CET"). + + We allow one level of symlink recursion for backward + compatibility with earlier timezone data packages that have + duplicate copies of the same timezone files inside the root + directory and the "posix" subdirectory (instead of symlinking). + This makes "posix/CET" still available, but helps to avoid + following such symlinks infinitely: + /usr/share/zoneinfo/posix/posix/posix/.../posix/ + */ + + /* + This is a normal case and not critical. only print warning if + verbose mode is chosen. + */ + if (verbose > 0) + { + fflush(stdout); + fprintf(stderr, "Warning: Skipping directory '%s': " + "to avoid infinite symlink recursion.\n", fullname); + } + continue; + } + if (scan_tz_dir(name_end_tmp, symlink_recursion_level + is_symlink, + verbose)) + { + my_dirend(cur_dir); + return 1; + } + } + else if (MY_S_ISREG(cur_dir->dir_entry[i].mystat->st_mode)) + { + init_alloc_root(PSI_INSTRUMENT_ME, &tz_storage, + 32768, 0, MYF(MY_THREAD_SPECIFIC)); + if (!tz_load(fullname, &tz_info, &tz_storage)) + print_tz_as_sql(root_name_end + 1, &tz_info); + else + { + /* + Some systems (like debian, opensuse etc) have description + files (.tab). We skip these silently if verbose is > 0 + */ + const char *current_ext= fn_ext(fullname); + my_bool known_ext= 0; + + for (const char **ext= known_extensions ; *ext ; ext++) + { + if (!strcmp(*ext, current_ext)) + { + known_ext= 1; + break; + } + } + if (verbose > 0 || !known_ext) + { + fflush(stdout); + fprintf(stderr, + "Warning: Unable to load '%s' as time zone. Skipping it.\n", + fullname); + } + } + free_root(&tz_storage, MYF(0)); + } + else + { + fflush(stdout); + fprintf(stderr, "Warning: '%s' is not regular file or directory\n", + fullname); + } + } + } + + my_dirend(cur_dir); + + return 0; +} + + +static const char *load_default_groups[]= +{ "mysql_tzinfo_to_sql", 0}; + +static struct my_option my_long_options[] = +{ + {"help", '?', "Display this help and exit.", 0, 0, 0, GET_NO_ARG, NO_ARG, + 0, 0, 0, 0, 0, 0}, +#ifdef DBUG_OFF + {"debug", '#', "This is a non-debug version. Catch this and exit", + 0,0, 0, GET_DISABLED, OPT_ARG, 0, 0, 0, 0, 0, 0}, +#else + {"debug", '#', "Output debug log. Often this is 'd:t:o,filename'.", + 0, 0, 0, GET_STR, OPT_ARG, 0, 0, 0, 0, 0, 0}, +#endif + {"leap", 'l', "Print the leap second information from the given time zone file. By convention, when --leap is used the next argument is the timezonefile", + &opt_leap, &opt_leap, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0}, + {"verbose", 'v', "Write non critical warnings", + &opt_verbose, &opt_verbose, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0}, + {"version", 'V', "Output version information and exit.", + 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0}, + {"skip-write-binlog", 'S', "Do not replicate changes to time zone tables to other nodes in a Galera cluster", + &opt_skip_write_binlog,&opt_skip_write_binlog, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0}, + { 0, 0, 0, 0, 0, 0, GET_NO_ARG, NO_ARG, 0, 0, 0, 0, 0, 0} +}; + + +C_MODE_START +static my_bool get_one_option(const struct my_option *, const char *, + const char *); +C_MODE_END + +static void print_version(void) +{ + printf("%s Ver %s Distrib %s, for %s (%s)\n",my_progname, PROGRAM_VERSION, + MYSQL_SERVER_VERSION,SYSTEM_TYPE,MACHINE_TYPE); +} + +static void print_usage(void) +{ + fprintf(stderr, "Usage:\n"); + fprintf(stderr, " %s [options] timezonedir\n", my_progname); + fprintf(stderr, " %s [options] timezonefile timezonename\n", my_progname); + print_defaults("my",load_default_groups); + puts(""); + my_print_help(my_long_options); + my_print_variables(my_long_options); +} + + +static my_bool +get_one_option(const struct my_option *opt, const char *argument, const char *) +{ + switch(opt->id) { + case '#': +#ifndef DBUG_OFF + DBUG_PUSH(argument ? argument : "d:t:S:i:O,/tmp/mysq_tzinfo_to_sql.trace"); +#endif + break; + case '?': + print_version(); + puts(""); + print_usage(); + exit(0); + case 'V': + print_version(); + exit(0); + } + return 0; +} + + +int +main(int argc, char **argv) +{ + char **default_argv; + MY_INIT(argv[0]); + + load_defaults_or_exit("my", load_default_groups, &argc, &argv); + default_argv= argv; + + if ((handle_options(&argc, &argv, my_long_options, get_one_option))) + exit(1); + + if ((argc != 1 && argc != 2) || (opt_leap && argc != 1)) + { + print_usage(); + free_defaults(default_argv); + return 1; + } + + if (opt_skip_write_binlog) + { + /* If skip_write_binlog is set and wsrep is compiled in we disable + sql_log_bin and wsrep_on to avoid Galera replicating below + truncate table clauses. This will allow user to set different + time zones to nodes in Galera cluster. */ + printf("set @prep1=if((select count(*) from information_schema.global_variables where variable_name='wsrep_on' and variable_value='ON'), 'SET SESSION SQL_LOG_BIN=?, WSREP_ON=OFF;', 'do ?');\n" + "prepare set_wsrep_write_binlog from @prep1;\n" + "set @toggle=0; execute set_wsrep_write_binlog using @toggle;\n"); + } + else + { + // Alter time zone tables to InnoDB if wsrep_on is enabled + // to allow changes to them to replicate with Galera + printf("\\d |\n" + "IF (select count(*) from information_schema.global_variables where\n" + "variable_name='wsrep_on' and variable_value='ON') = 1 THEN\n" + "ALTER TABLE time_zone ENGINE=InnoDB;\n" + "ALTER TABLE time_zone_name ENGINE=InnoDB;\n" + "ALTER TABLE time_zone_transition ENGINE=InnoDB;\n" + "ALTER TABLE time_zone_transition_type ENGINE=InnoDB;\n" + "END IF|\n" + "\\d ;\n"); + } + + if (argc == 1 && !opt_leap) + { + /* Argument is timezonedir */ + + root_name_end= strmake_buf(fullname, argv[0]); + + printf("TRUNCATE TABLE time_zone;\n"); + printf("TRUNCATE TABLE time_zone_name;\n"); + printf("TRUNCATE TABLE time_zone_transition;\n"); + printf("TRUNCATE TABLE time_zone_transition_type;\n"); + printf("START TRANSACTION;\n"); + + if (scan_tz_dir(root_name_end, 0, opt_verbose)) + { + printf("ROLLBACK;\n"); + fflush(stdout); + fprintf(stderr, + "There were fatal errors during processing " + "of zoneinfo directory '%s'\n", fullname); + return 1; + } + + printf("COMMIT;\n"); + printf("ALTER TABLE time_zone_transition " + "ORDER BY Time_zone_id, Transition_time;\n"); + printf("ALTER TABLE time_zone_transition_type " + "ORDER BY Time_zone_id, Transition_type_id;\n"); + } + else + { + /* + First argument is timezonefile. + The second is timezonename if opt_leap is not given + */ + init_alloc_root(PSI_INSTRUMENT_ME, &tz_storage, 32768, 0, MYF(0)); + + if (tz_load(argv[0], &tz_info, &tz_storage)) + { + fflush(stdout); + fprintf(stderr, "Problems with zoneinfo file '%s'\n", argv[0]); + return 1; + } + if (opt_leap) + print_tz_leaps_as_sql(&tz_info); + else + print_tz_as_sql(argv[1], &tz_info); + + free_root(&tz_storage, MYF(0)); + } + + if(!opt_skip_write_binlog) + { + // Fall back to Aria + printf("\\d |\n" + "IF (select count(*) from information_schema.global_variables where\n" + "variable_name='wsrep_on' and variable_value='ON') = 1 THEN\n" + "ALTER TABLE time_zone ENGINE=Aria;\n" + "ALTER TABLE time_zone_name ENGINE=Aria;\n" + "ALTER TABLE time_zone_transition ENGINE=Aria;\n" + "ALTER TABLE time_zone_transition_type ENGINE=Aria;\n" + "END IF|\n" + "\\d ;\n"); + } + + free_defaults(default_argv); + my_end(0); + return 0; +} + +#endif /* defined(TZINFO2SQL) */ + + +#ifdef TESTTIME + +/* + Some simple brute-force test which allowed to catch a pair of bugs. + Also can provide interesting facts about system's time zone support + implementation. +*/ + +#ifndef CHAR_BIT +#define CHAR_BIT 8 +#endif + +#ifndef TYPE_BIT +#define TYPE_BIT(type) (sizeof (type) * CHAR_BIT) +#endif + +#ifndef TYPE_SIGNED +#define TYPE_SIGNED(type) (((type) -1) < 0) +#endif + +my_bool +is_equal_TIME_tm(const TIME* time_arg, const struct tm * tm_arg) +{ + return (time_arg->year == (uint)tm_arg->tm_year+TM_YEAR_BASE) && + (time_arg->month == (uint)tm_arg->tm_mon+1) && + (time_arg->day == (uint)tm_arg->tm_mday) && + (time_arg->hour == (uint)tm_arg->tm_hour) && + (time_arg->minute == (uint)tm_arg->tm_min) && + (time_arg->second == (uint)tm_arg->tm_sec) && + time_arg->second_part == 0; +} + + +int +main(int argc, char **argv) +{ + my_bool localtime_negative; + TIME_ZONE_INFO tz_info; + struct tm tmp; + MYSQL_TIME time_tmp; + time_t t, t1, t2; + char fullname[FN_REFLEN+1]; + char *str_end; + MEM_ROOT tz_storage; + + MY_INIT(argv[0]); + + init_alloc_root(&tz_storage, "timezone_storage", 32768, MYF(0)); + + /* let us set some well known timezone */ + setenv("TZ", "MET", 1); + tzset(); + + /* Some initial time zone related system info */ + printf("time_t: %s %u bit\n", TYPE_SIGNED(time_t) ? "signed" : "unsigned", + (uint)TYPE_BIT(time_t)); + if (TYPE_SIGNED(time_t)) + { + t= -100; + localtime_negative= MY_TEST(localtime_r(&t, &tmp) != 0); + printf("localtime_r %s negative params \ + (time_t=%d is %d-%d-%d %d:%d:%d)\n", + (localtime_negative ? "supports" : "doesn't support"), (int)t, + TM_YEAR_BASE + tmp.tm_year, tmp.tm_mon + 1, tmp.tm_mday, + tmp.tm_hour, tmp.tm_min, tmp.tm_sec); + + printf("mktime %s negative results (%d)\n", + (t == mktime(&tmp) ? "doesn't support" : "supports"), + (int)mktime(&tmp)); + } + + tmp.tm_year= 103; tmp.tm_mon= 2; tmp.tm_mday= 30; + tmp.tm_hour= 2; tmp.tm_min= 30; tmp.tm_sec= 0; tmp.tm_isdst= -1; + t= mktime(&tmp); + printf("mktime returns %s for spring time gap (%d)\n", + (t != (time_t)-1 ? "something" : "error"), (int)t); + + tmp.tm_year= 103; tmp.tm_mon= 8; tmp.tm_mday= 1; + tmp.tm_hour= 0; tmp.tm_min= 0; tmp.tm_sec= 0; tmp.tm_isdst= 0; + t= mktime(&tmp); + printf("mktime returns %s for non existing date (%d)\n", + (t != (time_t)-1 ? "something" : "error"), (int)t); + + tmp.tm_year= 103; tmp.tm_mon= 8; tmp.tm_mday= 1; + tmp.tm_hour= 25; tmp.tm_min=0; tmp.tm_sec=0; tmp.tm_isdst=1; + t= mktime(&tmp); + printf("mktime %s unnormalized input (%d)\n", + (t != (time_t)-1 ? "handles" : "doesn't handle"), (int)t); + + tmp.tm_year= 103; tmp.tm_mon= 9; tmp.tm_mday= 26; + tmp.tm_hour= 0; tmp.tm_min= 30; tmp.tm_sec= 0; tmp.tm_isdst= 1; + mktime(&tmp); + tmp.tm_hour= 2; tmp.tm_isdst= -1; + t= mktime(&tmp); + tmp.tm_hour= 4; tmp.tm_isdst= 0; + mktime(&tmp); + tmp.tm_hour= 2; tmp.tm_isdst= -1; + t1= mktime(&tmp); + printf("mktime is %s (%d %d)\n", + (t == t1 ? "determenistic" : "is non-determenistic"), + (int)t, (int)t1); + + /* Let us load time zone description */ + str_end= strmake_buf(fullname, TZDIR); + strmake(str_end, "/MET", FN_REFLEN - (str_end - fullname)); + + if (tz_load(fullname, &tz_info, &tz_storage)) + { + printf("Unable to load time zone info from '%s'\n", fullname); + free_root(&tz_storage, MYF(0)); + return 1; + } + + printf("Testing our implementation\n"); + + if (TYPE_SIGNED(time_t) && localtime_negative) + { + for (t= -40000; t < 20000; t++) + { + localtime_r(&t, &tmp); + gmt_sec_to_TIME(&time_tmp, (my_time_t)t, &tz_info); + if (!is_equal_TIME_tm(&time_tmp, &tmp)) + { + printf("Problem with negative time_t = %d\n", (int)t); + free_root(&tz_storage, MYF(0)); + return 1; + } + } + printf("gmt_sec_to_TIME = localtime for time_t in [-40000,20000) range\n"); + } + + for (t= 1000000000; t < 1100000000; t+= 13) + { + localtime_r(&t,&tmp); + gmt_sec_to_TIME(&time_tmp, (my_time_t)t, &tz_info); + + if (!is_equal_TIME_tm(&time_tmp, &tmp)) + { + printf("Problem with time_t = %d\n", (int)t); + free_root(&tz_storage, MYF(0)); + return 1; + } + } + printf("gmt_sec_to_TIME = localtime for time_t in [1000000000,1100000000) range\n"); + + my_init_time(); + + /* + Be careful here! my_system_gmt_sec doesn't fully handle unnormalized + dates. + */ + for (time_tmp.year= 1980; time_tmp.year < 2010; time_tmp.year++) + { + for (time_tmp.month= 1; time_tmp.month < 13; time_tmp.month++) + { + for (time_tmp.day= 1; + time_tmp.day < mon_lengths[isleap(time_tmp.year)][time_tmp.month-1]; + time_tmp.day++) + { + for (time_tmp.hour= 0; time_tmp.hour < 24; time_tmp.hour++) + { + for (time_tmp.minute= 0; time_tmp.minute < 60; time_tmp.minute+= 5) + { + for (time_tmp.second=0; time_tmp.second<60; time_tmp.second+=25) + { + long not_used; + uint not_used_2; + t= (time_t)my_system_gmt_sec(&time_tmp, ¬_used, ¬_used_2); + t1= (time_t)TIME_to_gmt_sec(&time_tmp, &tz_info, ¬_used_2); + if (t != t1) + { + /* + We need special handling during autumn since my_system_gmt_sec + prefers greater time_t values (in MET) for ambiguity. + And BTW that is a bug which should be fixed !!! + */ + tmp.tm_year= time_tmp.year - TM_YEAR_BASE; + tmp.tm_mon= time_tmp.month - 1; + tmp.tm_mday= time_tmp.day; + tmp.tm_hour= time_tmp.hour; + tmp.tm_min= time_tmp.minute; + tmp.tm_sec= time_tmp.second; + tmp.tm_isdst= 1; + + t2= mktime(&tmp); + + if (t1 == t2) + continue; + + printf("Problem: %u/%u/%u %u:%u:%u with times t=%d, t1=%d\n", + time_tmp.year, time_tmp.month, time_tmp.day, + time_tmp.hour, time_tmp.minute, time_tmp.second, + (int)t,(int)t1); + + free_root(&tz_storage, MYF(0)); + return 1; + } + } + } + } + } + } + } + + printf("TIME_to_gmt_sec = my_system_gmt_sec for test range\n"); + + free_root(&tz_storage, MYF(0)); + return 0; +} + +#endif /* defined(TESTTIME) */ |