Merge recent changes from trunk.

FossilOrigin-Name: c69f030b1ed9bddcc9ea79fe2361f39901bf1461ba3efdb32ddabcaa44319b2a

diff --cc main.mk
Simple merge

diff --cc manifest
index b52a60cb98154ff55f7119113c654432d1f08856,09bc31b90444d3d89c07b59875ed9f2a67a8ef43..7ef76f04448a3e5966ae805ef6ba9defc9ef9521
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,5 -1,5 +1,5 @@@
- C Merge\srecent\strunk\senhancements\sinto\sthe\sbegin-concurrent-pnu\sbranch.
- D 2020-04-09T18:44:15.075
 -C Avoid\sharmless\sUB\sin\smemcpy()\sin\sthe\sJSON\sextension.
 -D 2020-05-17T13:47:28.477
++C Merge\srecent\schanges\sfrom\strunk.
++D 2020-05-18T16:19:59.437
  F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
  F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
  F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@@ -458,7 -455,7 +460,7 @@@ F ext/userauth/userauth.c 7f00cded7dcaa
  F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
  F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
  F magic.txt 8273bf49ba3b0c8559cb2774495390c31fd61c60
- F main.mk 9f5e3ae3817e33e96c038290d4ebc9e4eff9ef01514b187907b1261c659d61e4
 -F main.mk addd0a300e90ad090dc4a934df8a6f1b6c52c057a1aebb93682aed29fb68a345
++F main.mk b786ce086d5c37515473535722abc93a81ec645fca5f0baac3de9a446b90faad
  F mkso.sh fd21c06b063bb16a5d25deea1752c2da6ac3ed83
  F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
  F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
@@@ -470,28 -467,28 +472,28 @@@ F spec.template 86a4a43b99ebb3e75e6b9a7
  F sqlite.pc.in 42b7bf0d02e08b9e77734a47798d1a55a9e0716b
  F sqlite3.1 fc7ad8990fc8409983309bb80de8c811a7506786
  F sqlite3.pc.in 48fed132e7cb71ab676105d2a4dc77127d8c1f3a
- F src/alter.c fa2c3be9b0ebecfafb7062072a0ae6eda126d3e5a9fd51b2eded5acd95dc783c
- F src/analyze.c 831bb090988477a00d3b4c000746e1b0454dcc93b10b793e6ebe1c47f25d193a
+ F src/alter.c 826bc4561456094cf758f095776026f25892a2bb3a7cd86742323267dc9bdb5f
+ F src/analyze.c 953a6c43870ccaf080597244e1eeb4dc2ff6cb84f9501b24e46323de36970b61
  F src/attach.c ff2daea0fe62080192e3f262670e4f61f5a86c1e7bea9cec34e960fe79852aa1
  F src/auth.c a3d5bfdba83d25abed1013a8c7a5f204e2e29b0c25242a56bc02bb0c07bf1e06
- F src/backup.c 5e617c087f1c2d6005c2ec694ce80d6e16bc68d906e1b1c556d7c7c2228b636b
+ F src/backup.c b1c90cd4110248c8e1273ff4578d3a84c0c34725e1b96dacd4a6294a908702de
 -F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 +F src/bitvec.c 8433d9e98dd6f2ea3286e0d2fe5d65de1bfc18a706486eb2026b01be066b5806
  F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
- F src/btree.c 73d4dabe25aba95f3475c348ab2668fe713dd807d1582d5dd458978ecd0fc5d2
- F src/btree.h 58768397849b547fe49c3ec276fbf3f9443aae1ff46c9e94454bfebb5443ec24
- F src/btreeInt.h b0e3cdf8dba3b17b9f61736ce78c627a384907080e1ae159e1385be745001426
- F src/build.c e8ee72dc44d85d467df3a1069269b0fa31adf19408d75e9f7cb1afca7ce01e45
 -F src/btree.c f14e415fcfd0b52b4e4ebd193ba5fadac5e8252c30f023389af682813af44025
 -F src/btree.h 989ef3c33413549e3e148f3dcb46c030f317dac130dc86809ba6b9aa4b16c72a
 -F src/btreeInt.h 5c8b8749805787313ecf49eb5be3ced1e94bbf8ef54bb01470ce6bd0d5185c67
 -F src/build.c ca9e7a33b74f1bf2eb3a5f37f9d07dfed335469f2d70c0bd350e0dd42a50183a
++F src/btree.c 9cdd780b9eefae9d9356b907903afd407581a0d143de507238a82fa9259964e6
++F src/btree.h 024ee56278d64622b7fe9350b0a0cdadd57ccb1f6f2de279d2053458b16cae8c
++F src/btreeInt.h d92bf22ef471c3d877daa32e677755ac9578707089116a679481c646e6b3e0b0
++F src/build.c 87e14ac12acd6151b631537697a36c1cc2dd8b01c6bd3a6a74971cce077ddac3
  F src/callback.c d0b853dd413255d2e337b34545e54d888ea02f20da5ad0e63585b389624c4a6c
  F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
- F src/ctime.c 6a77ec9e0eb87aea929e002c816298907e337094a7b556898ae2d1e6be209f90
+ F src/ctime.c e98518d2d3d4029a13c805e07313fb60c877be56db76e90dd5f3af73085d0ce6
  F src/date.c b29b349d277e3d579dcc295b24c0a2caed83fd8f090a9f7cbe6070c0fd662384
  F src/dbpage.c 8a01e865bf8bc6d7b1844b4314443a6436c07c3efe1d488ed89e81719047833a
  F src/dbstat.c 793deaf88a0904f88285d93d6713c636d55ede0ffd9f08d10f4ea825531d367f
- F src/delete.c 11000121c4281c0bce4e41db29addfaea0038eaa127ece02557c9207bc3e541d
- F src/expr.c b292bdecd64cd695109ceaa3c810f8b41f202368c75adb9ea680a875df5b0308
+ F src/delete.c 88047c8e59878c920fce14582bc1dde4d81157d1ca5ffdf36c2907e6d41996c4
+ F src/expr.c 8eed44d9de8a3b0fe1c9809bb75a02b65488774c8ba8685512d8f63adade18e5
  F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
  F src/fkey.c 4b575423b0a5d4898b1a7868ce985cf1a8ad91c741c9abbb108ff02536d20f41
- F src/func.c e9fc14ee686360ff77884731eeb97233a50ca424fd705d4a8c04e2afcf7039b0
 -F src/func.c 2333eb4277f55a5efdc12ef754e7d7ec9105d257b2fd00301d23ce1e8fa67dc0
++F src/func.c 3796e7e269a9f23867ad3e64152399d5f850f83b9ee3ba57a931da7e46ef9c00
  F src/global.c 79a988b56b06ce2d08ebefe1d35da9aa25b3851faa47ea5233361c4827185a64
  F src/hash.c 8d7dda241d0ebdafb6ffdeda3149a412d7df75102cecfc1021c98d6219823b19
  F src/hash.h 9d56a9079d523b648774c1784b74b89bd93fac7b365210157482e4319a468f38
@@@ -499,9 -496,9 +501,9 @@@ F src/hwtime.h cb1d7e3e1ed94b7aa6fde95a
  F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
  F src/insert.c 8e4211d04eb460c0694d486c6ba1c068d468c6f653c3f237869a802ad82854de
  F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
- F src/loadext.c b179df50e6e8bb0c36c149e95d958d49bd8c6c7469e59c01b53d164360bc6c32
- F src/main.c 48eb5ecb2096222f23f38c619730891a9fb79e0fd6ccceab4c530816bd6a7ebf
- F src/malloc.c cabfef0d725e04c8abfe0231a556ed8b78bf329dcc3fddbf903f6cdcd53cf4e6
+ F src/loadext.c 421310045bd78afefb772294a99e50f37d87ae578786a6169074e6291e30d969
 -F src/main.c 97d962ab1f830540043042e41085c5b85636a60e6ed95002c1a56b64f7eb6a0b
++F src/main.c 1290592ac9c7bd928f17e30fe442e523d30ce7e9ebabf56e7979735c1c7ede36
+ F src/malloc.c d0400b0366e1a3a2414ca4534b4a7406df34732835f37a15cb4642eb7df1a363
  F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
  F src/mem1.c c12a42539b1ba105e3707d0e628ad70e611040d8f5e38cf942cee30c867083de
  F src/mem2.c f1940d9e91948dd6a908fbb9ce3835c36b5d83c3
@@@ -520,33 -517,33 +522,33 @@@ F src/os.c 669cc3839cc35d20f81faf0be1ab
  F src/os.h 48388821692e87da174ea198bf96b1b2d9d83be5dfc908f673ee21fafbe0d432
  F src/os_common.h b2f4707a603e36811d9b1a13278bffd757857b85
  F src/os_setup.h 0dbaea40a7d36bf311613d31342e0b99e2536586
- F src/os_unix.c 257dd274b6af477be8e1de3e43c5c83164fe7816bbfaeeff81d4bd5e65844992
- F src/os_win.c 035a813cbd17f355bdcad7ab894af214a9c13a1db8aeac902365350b98cd45a7
 -F src/os_unix.c 13f983da988b6460ef3c4c22099c67ab0938291e543644ac4d99eccc8ba604f1
++F src/os_unix.c 550f4daf483619ef8357d98e9caa7cc613d13369ed8ffef17994d5020c12879d
+ F src/os_win.c 317718e8f04c449e7d9e1eacac0d14e7508e4a77c9d4c3cb7382299bd24561b7
  F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
- F src/pager.c 025511c3e6ef9f384b2daa770e751fedc2f92924f78c075d44cd6492a428afa2
- F src/pager.h 2ed03fade1813e9d058a3dfce15427fe6deda8a6ada5acaf0c0970b22e13f9e5
 -F src/pager.c 96436cb1920074d4ade120a1a8a9d0ae3f52df06651e21b7eccc5eae2f02b111
 -F src/pager.h 8d1dc9a2c3fc5eb6eeed75f48a076f425e77706f8935f05817fa05a308f587b5
 -F src/parse.y c8eff38606f443d5ba245263fa7abc05e4116d95656e050c4b78e9bfbf931add
++F src/pager.c 6f559d65b422f773b12a9eca2c25eb4eee333b26a15c556a0a2e001f998a2624
++F src/pager.h 7fed31537daa2593ad18df5f4e00b2988a2e25d74de2ab525500a6e26673687d
 +F src/parse.y 0724899be1d00dc438d0acadbfc2baddd4132a47268f25676ac79d56c1ee7351
  F src/pcache.c 385ff064bca69789d199a98e2169445dc16e4291fa807babd61d4890c3b34177
  F src/pcache.h 4f87acd914cef5016fae3030343540d75f5b85a1877eed1a2a19b9f284248586
  F src/pcache1.c 6596e10baf3d8f84cc1585d226cf1ab26564a5f5caf85a15757a281ff977d51a
- F src/pragma.c 5fd004b89c77319008ddff6d65dcc83ccca9584d3048f4f66b108b5906a20dba
- F src/pragma.h 9a5f52a4397ce0d9b6e99f2e3b9b657335e09e32127c712a768ed2744a9088b0
+ F src/pragma.c 1b0db48177e52b256c003b8dc6ac708b1079a82cded944a23820574586a4731f
 -F src/pragma.h 8168e588536bffd95319451f34e9a754dc37d205ebe433031a7813c5b286beae
++F src/pragma.h f45ac571c578e80533f6c72df0725b7879bdf861fdf1f5b75433495dbecdb0aa
  F src/prepare.c 8d4d6c8aa6afefc48027c54b41cdf134b4d6bc2fc4badbe483ad7fd9e1728a28
- F src/printf.c 9be6945837c839ba57837b4bc3af349eba630920fa5532aa518816defe42a7d4
+ F src/printf.c ebf563cff3122f6a61149964b738b470196d3619df31d6a720d0ff72fcfd7c7b
 -F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 +F src/random.c f27af4099afaea7284ade5c206224dcfdb2334cfd119d018b470d46356b3f27d
  F src/resolve.c d36a2b1639e1c33d7b508abfd3452a63e7fd81737f6f3940bfef085fca6f21f4
  F src/rowset.c ba9515a922af32abe1f7d39406b9d35730ed65efab9443dc5702693b60854c92
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- F src/shell.c.in cf7d6140c33859a86188aa52093dfa5d4e4d9ce32ecf1d588a127cb0a8f6f96f
- F src/sqlite.h.in 9df0e92cf5c83269f5b7ccd0cce62265e92cf9031867d3a6e0e1c71e6be45eb6
 -F src/select.c ee4b02ad8047c35891b7a612091beec21ae7a0155290dcbefb0824aed20c46f3
++F src/select.c 23d31a8bb7b7a147e547a00a210ce2a96144e48651f2e9d5ab7cb13a655bf36f
+ F src/shell.c.in cf2d24f54412c06e5fb34af7fabc748651125e1dceac29b740e91f06d23447b6
 -F src/sqlite.h.in 74342b41e9d68ff9e56b192009046f8dd0aa2bd76ce1a588f330de614ba61de7
++F src/sqlite.h.in bfd502d24286258ce9091c7a2865c4e6e953958d489d50ad23e46ca1e37b03cc
  F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
- F src/sqlite3ext.h 9c5269260409eb3275324ccace6a13a96f4ad330c708415f70ca6097901ff4ee
- F src/sqliteInt.h d3098bfc4763743413568620ef22304783c2d4a14ed20495b81efba9564fd71c
+ F src/sqlite3ext.h 2d1af80082edffd71c6f96f70ad1ce6a4fb46615ad10291fc77fe0dea9ff0197
 -F src/sqliteInt.h 8878a88c18a013d1843638001d7fc56a8f99740f151fc7597b1641b61accf58c
++F src/sqliteInt.h 0cb5bc0bf42881511c19c704cce0f13cc1753154d465386ef2e3634b702fb009
  F src/sqliteLimit.h 95cb8479ca459496d9c1c6a9f76b38aee12203a56ce1092fe13e50ae2454c032
  F src/status.c 9ff2210207c6c3b4d9631a8241a7d45ab1b26a0e9c84cb07a9b5ce2de9a3b278
- F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
- F src/tclsqlite.c d0aa320416efe88c4dbb0156ed6c494f2f9958871a940e46984ee57b3e7fcc50
+ F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
+ F src/tclsqlite.c 986b6391f02cd9b53c1d688be55899f6ffddeb8e8014cd83c1b73ff912579a71
 -F src/test1.c 5e8b8cc54e8c88906ea8a084387aa79bad245e539f4cee73149e5c0527e1db16
 +F src/test1.c c84b9ca57d9953e17410b0ca17b8c4b18a6b44676fa95bc5524caa0f0820d6bd
  F src/test2.c 3efb99ab7f1fc8d154933e02ae1378bac9637da5
  F src/test3.c 61798bb0d38b915067a8c8e03f5a534b431181f802659a6616f9b4ff7d872644
  F src/test4.c 405834f6a93ec395cc4c9bb8ecebf7c3d8079e7ca16ae65e82d01afd229694bb
@@@ -603,24 -600,25 +605,25 @@@ F src/threads.c 4ae07fa022a3dc7c5beb373
  F src/tokenize.c eee7bae3ec0bc4abee951554bf46a8ba567c0f7752ac90c820ed8afff4c612dc
  F src/treeview.c 82c6391a3ba76215d4185fd4719a56ec4caf186a40c8a7b6e6ba4ae4467c2742
  F src/trigger.c 4ada1037cc99777f647a882cdacbd1a4deb6567b69daf02946286401b88cdc04
- F src/update.c 188f8d0622ac3c7250c5bc34bc44f5f37adc027a5f9925bfffb24699aeb71411
 -F src/update.c 3199098455830fc2d8c8fc4ae3ec2ea513eef64339ae9a7048db62b21169bc7a
++F src/update.c c4f659b15422b96bfad29cd98ce6e7884516abd12552491fcc5421463bbb7c4a
  F src/upsert.c 2920de71b20f04fe25eb00b655d086f0ba60ea133c59d7fa3325c49838818e78
  F src/utf.c 95fb6e03a5ca679045c5adccd05380f0addccabef5911abddcb06af069500ab7
  F src/util.c 3b6cedf7a0c69bd6e1acce832873952d416212d6293b18d03064e07d7a9b5118
- F src/vacuum.c b6a321f6c6068c49f763fda52a0cd75fae9228d31f121b977436a00a158f22dc
- F src/vdbe.c 2375edd8bd776c99a3b4cf6b87c08dfb973730a7de2b4f7b83f3194862498223
- F src/vdbe.h 51282fbe819ee0e8eeeaab176240860d334c20a12b14f3b363e7f1a4e05d60b9
- F src/vdbeInt.h 0b728ee662862a38b1912af741e2ac64f524de3c77aa86cf4306c42bdcd9de59
- F src/vdbeapi.c d176ee7251d5344de7bb2a0d2dd0fe536834e5843d9bc2389e0f5cdcd5374141
- F src/vdbeaux.c d49b9578906607b77e61e1251b636db7852bb3a64f7a736e92d4fffa68d200ac
 -F src/vacuum.c de9780b89fa4ee74c3534f60b94820e3179aca759ffc1338ee53cb4ea7693dd3
 -F src/vdbe.c e3dba0dee25bc92e871c13cac655260912b3be4abcc85b439259c9934b208da3
++F src/vacuum.c 28f9a2430bf250c04bbf40a70d749e8c081c007b99602df61717d35b29b817ab
++F src/vdbe.c 6c2fdb92f247c4174b00961142de873b21444362b0e27e579ee9e1eda2b18adc
+ F src/vdbe.h 07b8c636a87df8b6e58f29d6badd7f10d5844353deff1d7c88ed1c2bfe3bbd35
+ F src/vdbeInt.h 571413068b5ac07e2ed8ca7a02fa529622fd5455ae6981498376e5e492d2e5ef
+ F src/vdbeapi.c e467b75a710ea099f8d2d022abf601d2ccd05e28f63b44b12d93000b6a75f4a8
 -F src/vdbeaux.c 80626786d21296d9e7936186850343afe5fc6368ad9724a172e151788425a063
++F src/vdbeaux.c af90721686bc750f0ea4961c734648ed9233984521a53d59c5e58158abe413be
  F src/vdbeblob.c 253ed82894924c362a7fa3079551d3554cd1cdace39aa833da77d3bc67e7c1b1
  F src/vdbemem.c 39b942ecca179f4f30a32b54579a85d74ccaefa5af2a0ad2700abe5ef0768b22
  F src/vdbesort.c 2be76d26998ce2b3324cdcc9f6443728e54b6c7677c553ad909c7d7cfab587df
  F src/vdbetrace.c fa3bf238002f0bbbdfb66cc8afb0cea284ff9f148d6439bc1f6f2b4c3b7143f0
- F src/vtab.c 7b704a90515a239c6cdba6a66b1bb3a385e62326cceb5ecb05ec7a091d6b8515
+ F src/vdbevtab.c ee5b4c902fdda2230f9503ac7b84c6d614c91e8f6f4dc1633e2e8dfef8ffb144
+ F src/vtab.c 7b452592ed2ee95dedb1f323d557cebede5a6f3b4558b21a5dca527e6ae9b12c
  F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
- F src/wal.c ba72dad1ff020776599b34881fe328a1cd7e9c51d906238415215dd335177326
- F src/wal.h ac2100eeda406a4492b8c183154507532d23ab9d5a8e32e208adfe4f9ea554f9
 -F src/wal.c d0365581aed11a75e176f67cdbdc1bdfe685c5381a052360a00bbf58d3252fa0
 -F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
++F src/wal.c 64575942847dcf6738a7495d7cb3cf6362d11061e02efc24619d6dc857065c8b
++F src/wal.h 7ffe787437f20a098af347011967a6d3bb8e5c3dc645e6be59eff44d2b2c5297
  F src/walker.c 7c429c694abd12413a5c17aec9f47cfe9eba6807e6b0a32df883e8e3a14835ed
  F src/where.c 9546c82056e8cdb27291f98cf1adca5d271240b399bb97b32f77fc2bea6146c9
  F src/whereInt.h 6b874aa15f94e43a2cec1080be64d955b04deeafeac90ffb5d6975c0d511be3c
@@@ -1669,8 -1660,8 +1674,8 @@@ F test/vtab_alter.test 736e66fb5ec7b4fe
  F test/vtab_err.test dcc8b7b9cb67522b3fe7a272c73856829dae4ab7fdb30399aea1b6981bda2b65
  F test/vtab_shared.test 5253bff2355a9a3f014c15337da7e177ab0ef8ad
  F test/vtabdrop.test 65d4cf6722972e5499bdaf0c0d70ee3b8133944a4e4bc31862563f32a7edca12
- F test/wal.test cdf0ca6cc0447520d19ef1c83287824ebeb3e82d75af856511ba96841a79fc9b
+ F test/wal.test 16180bc4becda176428ad02eaea437b4b8f5ae099314de443a4e12b2dcc007a2
 -F test/wal2.test 537f59e5c5932e3b45bf3591ae3e48a2601360c2e52821b633e222fe6ebd5b09
 +F test/wal2.test 6af203a0eb4be054661d9e0072cb22402c78dea4a89a10b77e9118ae3b91148a
  F test/wal3.test 2a93004bc0fb2b5c29888964024695bade278ab2
  F test/wal4.test 4744e155cd6299c6bd99d3eab1c82f77db9cdb3c
  F test/wal5.test 9c11da7aeccd83a46d79a556ad11a18d3cb15aa9
@@@ -1807,7 -1799,7 +1813,7 @@@ F tool/mkmsvcmin.tcl 6ecab9fe22c2c8de4d
  F tool/mkopcodec.tcl d1b6362bd3aa80d5520d4d6f3765badf01f6c43c
  F tool/mkopcodeh.tcl 352a4319c0ad869eb26442bf7c3b015aa15594c21f1cce5a6420dbe999367c21
  F tool/mkopts.tcl 680f785fdb09729fd9ac50632413da4eadbdf9071535e3f26d03795828ab07fa
- F tool/mkpragmatab.tcl e7cec3e2c6a95b55dd3a17b4f133c4e9bf6e2133c5b79cd1112f47c64ad26f48
 -F tool/mkpragmatab.tcl d348a4bf71ac068bddf89326562071cbbd962273d88f9b5e5d622f3e73b78bdf
++F tool/mkpragmatab.tcl b4074a101791d034bd3a5b8a6c69e9c4c8b7c420914f647ae78419130938f6d1
  F tool/mkshellc.tcl 70a9978e363b0f3280ca9ce1c46d72563ff479c1930a12a7375e3881b7325712
  F tool/mksourceid.c 36aa8020014aed0836fd13c51d6dc9219b0df1761d6b5f58ff5b616211b079b9
  F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
@@@ -1874,7 -1866,7 +1880,7 @@@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a9
  F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
  F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
  F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
- P 1e2109fd339cfb3b906673479672ed2e5a0dc17a94210f364c6fc1a657a62ae8 85d3dc8c50d8dbb8eac1956e8976e861d3b671e03355ca9257060fa3dca51cc4
- R 051fc8d3d56484207a7985fdb6780e2d
 -P 1313557b512297e7b75ed748894379b2022aecf696d5a58318e46a668321c1ff
 -R 0a3aaa0509481c9d6269f1e12c4b65a3
++P cedd138c749b777de0479a9e57aa9fe4f21cb99660abdc78c14e61afdef4f2f3 69e149f76853d196c8855fedfc98848b60fb116ac36bc08824b1a122469f8ece
++R 273ecb9bd25ca90e7692c8891452bfbd
  U drh
- Z 04e3a133efd17612f3969ea20ac459ce
 -Z c1782df13623caf985a15e6cbac97877
++Z 5a2a1344700e13213bc7143cc53246ed

diff --cc manifest.uuid
index 093a110d46e08f98fb09c44c325e6a6a4e1ccc2d,892a8523c0d669097c4d7d0145f17285a5d61d36..6c17632fbd8117e16229668ede4e72238ec4c8c1
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- cedd138c749b777de0479a9e57aa9fe4f21cb99660abdc78c14e61afdef4f2f3
 -69e149f76853d196c8855fedfc98848b60fb116ac36bc08824b1a122469f8ece
++c69f030b1ed9bddcc9ea79fe2361f39901bf1461ba3efdb32ddabcaa44319b2a

diff --cc src/btree.c
index ca0da9c26ed753e5d76fc741ad4d8b6ca2b28c7a,f269b3deee7a352c7d5a02807b98c374e0c15f28..e34584f9b2ae07dc514cfc8fa7bba4af70216221
--- 1/src/btree.c
--- 2/src/btree.c
+++ b/src/btree.c
@@@ -3621,8 -3371,8 +3622,9 @@@ int sqlite3BtreeNewDb(Btree *p)
  */
  int sqlite3BtreeBeginTrans(Btree *p, int wrflag, int *pSchemaVersion){
    BtShared *pBt = p->pBt;
+   Pager *pPager = pBt->pPager;
    int rc = SQLITE_OK;
 +  int bConcurrent = (p->db->bConcurrent && !ISAUTOVACUUM);
  
    sqlite3BtreeEnter(p);
    btreeIntegrity(p);
@@@ -3698,8 -3460,7 +3712,8 @@@
        if( (pBt->btsFlags & BTS_READ_ONLY)!=0 ){
          rc = SQLITE_READONLY;
        }else{
 -        rc = sqlite3PagerBegin(pPager, wrflag>1, sqlite3TempInMemory(p->db));
 +        int exFlag = bConcurrent ? -1 : (wrflag>1);
-         rc = sqlite3PagerBegin(pBt->pPager, exFlag, sqlite3TempInMemory(p->db));
++        rc = sqlite3PagerBegin(pPager, exFlag, sqlite3TempInMemory(p->db));
          if( rc==SQLITE_OK ){
            rc = newDatabase(pBt);
          }else if( rc==SQLITE_BUSY_SNAPSHOT && pBt->inTransaction==TRANS_NONE ){
@@@ -3777,11 -3533,7 +3795,12 @@@ trans_begun
        ** open savepoints. If the second parameter is greater than 0 and
        ** the sub-journal is not already open, then it will be opened here.
        */
 +      int nSavepoint = p->db->nSavepoint;
 +      rc = sqlite3PagerOpenSavepoint(pBt->pPager, nSavepoint);
 +      if( rc==SQLITE_OK && nSavepoint ){
 +        rc = btreePtrmapBegin(pBt, nSavepoint);
 +      }
+       rc = sqlite3PagerOpenSavepoint(pPager, p->db->nSavepoint);
      }
    }
  

diff --cc src/btree.h
Simple merge

diff --cc src/btreeInt.h
Simple merge

diff --cc src/build.c
Simple merge

diff --cc src/func.c
Simple merge

diff --cc src/main.c
Simple merge

diff --cc src/os_unix.c
Simple merge

diff --cc src/pager.c
Simple merge

diff --cc src/pager.h
Simple merge

diff --cc src/pragma.h
Simple merge

diff --cc src/select.c
Simple merge

diff --cc src/sqlite.h.in
Simple merge

diff --cc src/sqliteInt.h
Simple merge

diff --cc src/update.c
Simple merge

diff --cc src/vacuum.c
Simple merge

diff --cc src/vdbe.c
Simple merge

diff --cc src/vdbeaux.c
Simple merge

diff --cc src/wal.c
index 4e4c8de498db0d8ec52b405821a1edc14844d499,e8f7f24f85d7b47b9d846a13091f14a9b754211e..887fb266a586ba2477a013491777c29512a65e5f
--- 1/src/wal.c
--- 2/src/wal.c
+++ b/src/wal.c
@@@ -2797,17 -2879,6 +2898,7 @@@ int sqlite3WalBeginReadTransaction(Wal 
    testcase( rc==SQLITE_PROTOCOL );
    testcase( rc==SQLITE_OK );
  
- #ifdef SQLITE_ENABLE_SETLK_TIMEOUT
-   /* If they were disabled earlier and the read-transaction has been
-   ** successfully opened, re-enable blocking locks. This is because the
-   ** connection may attempt to upgrade to a write-transaction, which does
-   ** benefit from using blocking locks.  */
-   if( rc==SQLITE_OK ){
-     sqlite3OsFileControl(pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&tmout);
-   }
- #endif
- 
 +  pWal->nPriorFrame = pWal->hdr.mxFrame;
  #ifdef SQLITE_ENABLE_SNAPSHOT
    if( rc==SQLITE_OK ){
      if( pSnapshot && memcmp(pSnapshot, &pWal->hdr, sizeof(WalIndexHdr))!=0 ){
@@@ -3067,171 -3104,46 +3152,183 @@@ static int walWriteLock(Wal *pWal)
  ** There can only be a single writer active at a time.
  */
  int sqlite3WalBeginWriteTransaction(Wal *pWal){
-   int rc = walWriteLock(pWal);
+   int rc;
+ 
+ #ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+   /* If the write-lock is already held, then it was obtained before the
+   ** read-transaction was even opened, making this call a no-op.
+   ** Return early. */
+   if( pWal->writeLock ){
+     assert( !memcmp(&pWal->hdr,(void *)walIndexHdr(pWal),sizeof(WalIndexHdr)) );
+     return SQLITE_OK;
+   }
+ #endif
++  
++  rc = walWriteLock(pWal);
 +  if( rc==SQLITE_OK ){
 +    /* If another connection has written to the database file since the
 +    ** time the read transaction on this connection was started, then
 +    ** the write is disallowed. Release the WRITER lock and return
 +    ** SQLITE_BUSY_SNAPSHOT in this case.  */
 +    if( memcmp(&pWal->hdr, (void *)walIndexHdr(pWal), sizeof(WalIndexHdr))!=0 ){
 +      walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
 +      pWal->writeLock = 0;
 +      rc = SQLITE_BUSY_SNAPSHOT;
 +    }
 +  }
 +  return rc;
 +}
  
 -  /* Cannot start a write transaction without first holding a read
 -  ** transaction. */
 -  assert( pWal->readLock>=0 );
 -  assert( pWal->writeLock==0 && pWal->iReCksum==0 );
 +/*
 +** This function is called by a writer that has a read-lock on aReadmark[0]
 +** (pWal->readLock==0). This function relinquishes that lock and takes a
 +** lock on a different aReadmark[] slot. 
 +**
 +** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
 +*/
 +static int walUpgradeReadlock(Wal *pWal){
 +  int cnt;
 +  int rc;
 +  assert( pWal->writeLock && pWal->readLock==0 );
 +  walUnlockShared(pWal, WAL_READ_LOCK(0));
 +  pWal->readLock = -1;
 +  cnt = 0;
 +  do{
 +    int notUsed;
 +    rc = walTryBeginRead(pWal, &notUsed, 1, ++cnt);
 +  }while( rc==WAL_RETRY );
 +  assert( (rc&0xff)!=SQLITE_BUSY ); /* BUSY not possible when useWal==1 */
 +  testcase( (rc&0xff)==SQLITE_IOERR );
 +  testcase( rc==SQLITE_PROTOCOL );
 +  testcase( rc==SQLITE_OK );
 +  return rc;
 +}
  
 -  if( pWal->readOnly ){
 -    return SQLITE_READONLY;
 -  }
  
 -  /* Only one writer allowed at a time.  Get the write lock.  Return
 -  ** SQLITE_BUSY if unable.
 -  */
 -  rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1);
 -  if( rc ){
 -    return rc;
 -  }
 -  pWal->writeLock = 1;
 +#ifndef SQLITE_OMIT_CONCURRENT
 +/* 
 +** This function is only ever called when committing a "BEGIN CONCURRENT"
 +** transaction. It may be assumed that no frames have been written to
 +** the wal file. The second parameter is a pointer to the in-memory 
 +** representation of page 1 of the database (which may or may not be
 +** dirty). The third is a bitvec with a bit set for each page in the
 +** database file that was read by the current concurrent transaction.
 +**
 +** This function performs three tasks:
 +**
 +**   1) It obtains the WRITER lock on the wal file,
 +**
 +**   2) It checks that there are no conflicts between the current
 +**      transaction and any transactions committed to the wal file since
 +**      it was opened, and
 +**
 +**   3) It ejects any non-dirty pages from the page-cache that have been
 +**      written by another client since the CONCURRENT transaction was started
 +**      (so as to avoid ending up with an inconsistent cache after the
 +**      current transaction is committed).
 +**
 +** If no error occurs and the caller may proceed with committing the 
 +** transaction, SQLITE_OK is returned. SQLITE_BUSY is returned if the WRITER
 +** lock cannot be obtained. Or, if the WRITER lock can be obtained but there
 +** are conflicts with a committed transaction, SQLITE_BUSY_SNAPSHOT. Finally,
 +** if an error (i.e. an OOM condition or IO error), an SQLite error code
 +** is returned.
 +*/
 +int sqlite3WalLockForCommit(
 +  Wal *pWal, 
 +  PgHdr *pPage1, 
 +  Bitvec *pAllRead, 
 +  Pgno *piConflict
 +){
 +  Pager *pPager = pPage1->pPager;
 +  int rc = walWriteLock(pWal);
  
 -  /* If another connection has written to the database file since the
 -  ** time the read transaction on this connection was started, then
 -  ** the write is disallowed.
 +  /* If the database has been modified since this transaction was started,
 +  ** check if it is still possible to commit. The transaction can be 
 +  ** committed if:
 +  **
 +  **   a) None of the pages in pList have been modified since the 
 +  **      transaction opened, and
 +  **
 +  **   b) The database schema cookie has not been modified since the
 +  **      transaction was started.
    */
 -  if( memcmp(&pWal->hdr, (void *)walIndexHdr(pWal), sizeof(WalIndexHdr))!=0 ){
 -    walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
 -    pWal->writeLock = 0;
 -    rc = SQLITE_BUSY_SNAPSHOT;
 +  if( rc==SQLITE_OK ){
 +    WalIndexHdr head;
 +
 +    if( walIndexLoadHdr(pWal, &head) ){
 +      /* This branch is taken if the wal-index header is corrupted. This 
 +      ** occurs if some other writer has crashed while committing a 
 +      ** transaction to this database since the current concurrent transaction
 +      ** was opened.  */
 +      rc = SQLITE_BUSY_SNAPSHOT;
 +    }else if( memcmp(&pWal->hdr, (void*)&head, sizeof(WalIndexHdr))!=0 ){
 +      int iHash;
 +      int iLastHash = walFramePage(head.mxFrame);
 +      u32 iFirst = pWal->hdr.mxFrame+1;     /* First wal frame to check */
 +      if( memcmp(pWal->hdr.aSalt, (u32*)head.aSalt, sizeof(u32)*2) ){
 +        assert( pWal->readLock==0 );
 +        iFirst = 1;
 +      }
 +      for(iHash=walFramePage(iFirst); iHash<=iLastHash; iHash++){
 +        WalHashLoc sLoc;
 +
 +        rc = walHashGet(pWal, iHash, &sLoc);
 +        if( rc==SQLITE_OK ){
 +          u32 i, iMin, iMax;
 +          assert( head.mxFrame>=sLoc.iZero );
 +          iMin = (sLoc.iZero >= iFirst) ? 1 : (iFirst - sLoc.iZero);
 +          iMax = (iHash==0) ? HASHTABLE_NPAGE_ONE : HASHTABLE_NPAGE;
 +          if( iMax>(head.mxFrame-sLoc.iZero) ) iMax = (head.mxFrame-sLoc.iZero);
 +          for(i=iMin; rc==SQLITE_OK && i<=iMax; i++){
 +            PgHdr *pPg;
 +            if( sLoc.aPgno[i]==1 ){
 +              /* Check that the schema cookie has not been modified. If
 +              ** it has not, the commit can proceed. */
 +              u8 aNew[4];
 +              u8 *aOld = &((u8*)pPage1->pData)[40];
 +              int sz;
 +              i64 iOffset;
 +              sz = pWal->hdr.szPage;
 +              sz = (sz&0xfe00) + ((sz&0x0001)<<16);
 +              iOffset = walFrameOffset(i+sLoc.iZero, sz) + WAL_FRAME_HDRSIZE+40;
 +              rc = sqlite3OsRead(pWal->pWalFd, aNew, sizeof(aNew), iOffset);
 +              if( rc==SQLITE_OK && memcmp(aOld, aNew, sizeof(aNew)) ){
 +                rc = SQLITE_BUSY_SNAPSHOT;
 +              }
 +            }else if( sqlite3BitvecTestNotNull(pAllRead, sLoc.aPgno[i]) ){
 +              *piConflict = sLoc.aPgno[i];
 +              rc = SQLITE_BUSY_SNAPSHOT;
 +            }else if( (pPg = sqlite3PagerLookup(pPager, sLoc.aPgno[i])) ){
 +              /* Page aPgno[i], which is present in the pager cache, has been
 +              ** modified since the current CONCURRENT transaction was started.
 +              ** However it was not read by the current transaction, so is not
 +              ** a conflict. There are two possibilities: (a) the page was
 +              ** allocated at the of the file by the current transaction or 
 +              ** (b) was present in the cache at the start of the transaction.
 +              **
 +              ** For case (a), do nothing. This page will be moved within the
 +              ** database file by the commit code to avoid the conflict. The
 +              ** call to PagerUnref() is to release the reference grabbed by
 +              ** the sqlite3PagerLookup() above.  
 +              **
 +              ** In case (b), drop the page from the cache - otherwise
 +              ** following the snapshot upgrade the cache would be inconsistent
 +              ** with the database as stored on disk. */
 +              if( sqlite3PagerIswriteable(pPg) ){
 +                sqlite3PagerUnref(pPg);
 +              }else{
 +                sqlite3PcacheDrop(pPg);
 +              }
 +            }
 +          }
 +        }
 +        if( rc!=SQLITE_OK ) break;
 +      }
 +    }
    }
  
 +  pWal->nPriorFrame = pWal->hdr.mxFrame;
    return rc;
  }
  

diff --cc src/wal.h
index 9878852c763cb6ba0019ed7d996305c6a2773582,02e2bab36053886842a7a19f58427a0f1435a880..3f0e2d8d27337ecca62441da3773d70afdfcac58
--- 1/src/wal.h
--- 2/src/wal.h
+++ b/src/wal.h
@@@ -155,8 -146,10 +155,13 @@@ int sqlite3WalFramesize(Wal *pWal)
  /* Return the sqlite3_file object for the WAL file */
  sqlite3_file *sqlite3WalFile(Wal *pWal);
  
+ #ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+ int sqlite3WalWriteLock(Wal *pWal, int bLock);
+ void sqlite3WalDb(Wal *pWal, sqlite3 *db);
+ #endif
+ 
 +/* sqlite3_wal_info() data */
 +int sqlite3WalInfo(Wal *pWal, u32 *pnPrior, u32 *pnFrame);
 +
  #endif /* ifndef SQLITE_OMIT_WAL */
  #endif /* SQLITE_WAL_H */

diff --cc tool/mkpragmatab.tcl
Simple merge