From: drh <>
Date: Mon, 19 Aug 2024 14:23:57 +0000 (+0000)
Subject: Fix leap-year handling for dates prior to 0400-03-01.
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2110735fab52201a21e76531e71d8684e695b895;p=thirdparty%2Fsqlite.git

Fix leap-year handling for dates prior to 0400-03-01.

FossilOrigin-Name: 6767bf1c6713795a360da218a4e0f8106a264b54333849dd18b951ef6a82cba4
---

diff --git a/manifest b/manifest
index a83c5c071a..3101658c80 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Version\s3.46.1
-D 2024-08-13T09:16:08.704
+C Fix\sleap-year\shandling\sfor\sdates\sprior\sto\s0400-03-01.
+D 2024-08-19T14:23:57.073
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -700,7 +700,7 @@ F src/build.c 237ccc0290d131d646be722f418e92ee0a38043aee25e7dfdc75f8ce5b3abe4e
 F src/callback.c db3a45e376deff6a16c0058163fe0ae2b73a2945f3f408ca32cf74960b28d490
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c 64e4b1227b4ed123146f0aa2989131d1fbd9b927b11e80c9d58c6a68f9cd5ce3
-F src/date.c 126ba2ab10aeb2e7ba6e089b5f07b747c0625b8287f78b60da346eda8d23c875
+F src/date.c a3e9ff72b3696b746363d46bbc9dfbd70745f3108c7680f88da79176b309c0d4
 F src/dbpage.c 80e46e1df623ec40486da7a5086cb723b0275a6e2a7b01d9f9b5da0f04ba2782
 F src/dbstat.c 3b677254d512fcafd4d0b341bf267b38b235ccfddbef24f9154e19360fa22e43
 F src/delete.c cb766727c78e715f9fb7ec8a7d03658ed2a3016343ca687acfcec9083cdca500
@@ -1052,6 +1052,7 @@ F test/date.test c8ff835023f2107b57ce7a45c92265d51c98a23fc93231e998f12d850831aad
 F test/date2.test 7e12ec14aaf4d5e6294b4ba140445b0eca06ea50062a9c3a69c4ee13d0b6f8b1
 F test/date3.test a1b77abf05c6772fe5ca2337cac1398892f2a41e62bce7e6be0f4a08a0e64ae5
 F test/date4.test 75dc8401e8c0639a228cd26a6eaa4ff5ea8ccda912b9853d1c9462c476670e17
+F test/date5.test 14ba189bc4d03efc371dd5302e035764f6633355a3e13acb4a45e7b33530231e
 F test/dbdata.test 042f49acff3438f940eeba5868d3af080ae64ddf26ae78f80c92bec3ca7d8603
 F test/dbfuzz.c 73047c920d6210e5912c87cdffd9a1c281d4252e
 F test/dbfuzz001.test 6c9a4622029d69dc38926f115864b055cb2f39badd25ec22cbfb130c8ba8e9c3
@@ -2191,10 +2192,9 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P fc956353d3762d0e655b88f9d0c1a3840b40453a22e97160ccdf60485be56a92
-R 47b9d94ac84047bf00fd35221bcbfde9
-T +sym-release *
-T +sym-version-3.46.1 *
+P c9c2ab54ba1f5f46360f1b4f35d849cd3f080e6fc2b6c60e91b16c63f69a1e33
+Q +474b7e34b83bc5e85854bc3b386f31ff39b390549d89b94921f33bbc5b658d1d
+R 1e40592919c74a0f6624604d0cccc039
 U drh
-Z 519cc14a63561bb4dfa17935ffe00a32
+Z e341397c58ff7c6668cbd648792386ce
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 43d669ec29..2d58f211ab 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-c9c2ab54ba1f5f46360f1b4f35d849cd3f080e6fc2b6c60e91b16c63f69a1e33
+6767bf1c6713795a360da218a4e0f8106a264b54333849dd18b951ef6a82cba4
diff --git a/src/date.c b/src/date.c
index d74cecb1d9..a89051e87d 100644
--- a/src/date.c
+++ b/src/date.c
@@ -271,8 +271,8 @@ static void computeJD(DateTime *p){
     Y--;
     M += 12;
   }
-  A = Y/100;
-  B = 2 - A + (A/4);
+  A = (Y+4800)/100;
+  B = 38 - A + (A/4);
   X1 = 36525*(Y+4716)/100;
   X2 = 306001*(M+1)/10000;
   p->iJD = (sqlite3_int64)((X1 + X2 + D + B - 1524.5 ) * 86400000);
@@ -456,7 +456,7 @@ static int validJulianDay(sqlite3_int64 iJD){
 ** Compute the Year, Month, and Day from the julian day number.
 */
 static void computeYMD(DateTime *p){
-  int Z, A, B, C, D, E, X1;
+  int Z, alpha, A, B, C, D, E, X1;
   if( p->validYMD ) return;
   if( !p->validJD ){
     p->Y = 2000;
@@ -467,8 +467,8 @@ static void computeYMD(DateTime *p){
     return;
   }else{
     Z = (int)((p->iJD + 43200000)/86400000);
-    A = (int)((Z - 1867216.25)/36524.25);
-    A = Z + 1 + A - (A/4);
+    alpha = (int)((Z + 32044.75)/36524.25) - 52;
+    A = Z + 1 + alpha - ((alpha+100)/4) + 25;
     B = A + 1524;
     C = (int)((B - 122.1)/365.25);
     D = (36525*(C&32767))/100;
diff --git a/test/date5.test b/test/date5.test
new file mode 100644
index 0000000000..688f84d0f1
--- /dev/null
+++ b/test/date5.test
@@ -0,0 +1,86 @@
+# 2024-08-19
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# https://sqlite.org/forum/forumpost/eaa0a09786c6368b
+#
+# Apparently SQLite has been miscomputing leap-year dates before
+# the year 0400.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+# Skip this whole file if date and time functions are omitted
+# at compile-time
+#
+ifcapable {!datetime} {
+  finish_test
+  return
+}
+
+# Data sources:
+#   1-10  https://ssd.jpl.nasa.gov/tools/jdc/#/cd
+#   11    Jean Meeus, Astronomical Algorithms, ISBN 0-943396-61-1, p.59
+#   12    https://en.wikipedia.org/wiki/Julian_day
+#   
+# ID YEAR MONTH DAY JD
+set date5data {
+   1 2024     2  29 2460369.5
+   2 2024     3   1 2460370.5
+   3 2023     2  28 2460003.5
+   4 2023     3   1 2460004.5
+   5 2000     2  29 2451603.5
+   6 2000     3   1 2451604.5
+   7 1900     2  28 2415078.5
+   8 1900     3   1 2415079.5
+   9 1712     2  29 2346413.5
+  10 1712     3   1 2346414.5
+  11 1977     4  26 2443259.5
+  12 2013     1   1 2456293.5
+}
+
+foreach {id y m d jd} $date5data {
+  set date [format %04d-%02d-%02d $y $m $d]
+  do_execsql_test date5-jd$jd {
+    SELECT date($::jd);
+  } $date
+  do_execsql_test date5-cal/$date {
+    SELECT julianday($::date);
+  } $jd
+  for {set i 1} {$y+400*$i<=9999} {incr i} {
+    set y2 [expr {$y+400*$i}]
+    set date2 [format %04d-%02d-%02d $y2 $m $d]
+    set jd2 [expr {$jd+146097*$i}]
+    do_execsql_test date5-jd$jd2 {
+      SELECT date($::jd2);
+    } $date2
+    do_execsql_test date5-cal/$date2 {
+      SELECT julianday($::date2);
+    } $jd2
+  }
+  for {set i 1} {$y-400*$i>=-4712} {incr i} {
+    set y2 [expr {$y-400*$i}]
+    if {$y2<0} {
+      set date2 [format -%04d-%02d-%02d [expr {-$y2}] $m $d]
+    } else {
+      set date2 [format %04d-%02d-%02d $y2 $m $d]
+    }
+    set jd2 [expr {$jd-146097*$i}]
+    do_execsql_test date5-jd$jd2 {
+      SELECT date($::jd2);
+    } $date2
+    do_execsql_test date5-cal/$date2 {
+      SELECT julianday($::date2);
+    } $jd2
+  }
+}
+
+finish_test