Add the "PRAGMA secure_delete=FAST" option, which overwrites most deleted

content without increasing the amount of I/O.  Deleted content might persist
on the free page list, however.  And extra CPU cycles are used for zeroing,
of course.

FossilOrigin-Name: 38978ce65b280bb7cba3fc08ba91485fb1b84cd9fbba2e950ecf41c021ff452a

diff --cc manifest
index 0f6d0fc92b184f685a7a31bcb97402694b14d121,bf0d4f677ad42d66fde9993fe83788b25e250136..c2a863179760c1ec51a681a2da0bc3700a2ef631
--- 1/manifest
--- 2/manifest
+++ b/manifest
@@@ -1,8 -1,8 +1,8 @@@
- C Change\sthe\serror\smessage\stext\sfor\sSQLITE_ERROR\sto\somit\sthe\spart\sabout\n"missing\sdatabase"\sas\sthat\smeaning\sis\snow\sobsolete\s(since\sapprox\sSQLite\s2.0).
- D 2017-07-07T19:43:23.476
 -C Experimental\s"PRAGMA\ssecure_delete=FAST"\spragma.\s\sThe\sintent\sis\sto\soverwrite\ndeleted\scontent\swith\szeros\swithout\sincreasing\sthe\samount\sof\sdisk\sI/O.
 -D 2017-06-19T11:44:22.399
 -F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
++C Add\sthe\s"PRAGMA\ssecure_delete=FAST"\soption,\swhich\soverwrites\smost\sdeleted\ncontent\swithout\sincreasing\sthe\samount\sof\sI/O.\s\sDeleted\scontent\smight\spersist\non\sthe\sfree\spage\slist,\showever.\s\sAnd\sextra\sCPU\scycles\sare\sused\sfor\szeroing,\nof\scourse.
++D 2017-07-07T20:06:28.516
 +F Makefile.in 081e48dfe7f995d57ce1a88ddf4d2917b4349158648a6cd45b42beae30de3a12
  F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 -F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
 +F Makefile.msc 20850e3e8d4d4791e0531955852d768eb06f24138214870d543abb1a47346fba
  F README.md 2b15fae33852f2f53996774c21fb41e1d94181c4401a0e43ac93e11f2cc901b9
  F VERSION 87f1498f27e398bce3da2fa8125c9879a38ed9d87e4b5fb922b351de1e25cadb
  F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
@@@ -391,13 -348,13 +391,13 @@@ F src/auth.c 79f96c6f33bf0e5da8d1c282ce
  F src/backup.c faf17e60b43233c214aae6a8179d24503a61e83b
  F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
  F src/btmutex.c 0e9ce2d56159b89b9bc8e197e023ee11e39ff8ca
- F src/btree.c 00579ff9c2831d6f98cc993f8f2a34c0ff996e89b3cd2f27928f75796bc3a58a
 -F src/btree.c 127ae15b6328376fa549a2ead30a3ec20db31fe991a287c42cf394965f55fff0
++F src/btree.c 79fb003347c47c74f8fda24f2fd332321da616771cd3d1b3258b739f569ec625
  F src/btree.h 3edc5329bc59534d2d15b4f069a9f54b779a7e51289e98fa481ae3c0e526a5ca
- F src/btreeInt.h a392d353104b4add58b4a59cb185f5d5693dde832c565b77d8d4c343ed98f610
+ F src/btreeInt.h 97700795edf8a43245720414798b7b29d8e465aef46bf301ffacd431910c0da1
 -F src/build.c 88a8cdc11d1c081ed565aa3e795bdf9160f4556463b4c4555e9860b59dd80340
 -F src/callback.c 2e76147783386374bf01b227f752c81ec872d730
 +F src/build.c 74108007d286232fb4290464ee5452fa860c26215f8caa0e6c7cbf69a6fafe8f
 +F src/callback.c 8e14b60d1ed1c87c02cb5f121ecda99224f2aea6524a77ee6f72c9b5c7110f84
  F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 -F src/ctime.c eeff225a310b2d9a2a6cb413acaf78ab301b142ed3bcd83f0c06298f609373cb
 +F src/ctime.c 928954802b1397d9fb1378c7eb702c94b4735bbab1d5793e21b6a77734f56a1b
  F src/date.c cc42a41c7422389860d40419a5e3bce5eaf6e7835c3ba2677751dc653550a5c7
  F src/dbstat.c 19ee7a4e89979d4df8e44cfac7a8f905ec89b77d
  F src/delete.c 3213547e97b676c6fa79948b7a9ede4801ea04a01a2043241deafedf132ecf5d
@@@ -441,19 -398,19 +441,19 @@@ F src/parse.y 71bf06b02f567232deabe2586
  F src/pcache.c 62835bed959e2914edd26afadfecce29ece0e870
  F src/pcache.h 521bb9610d38ef17a3cc9b5ddafd4546c2ea67fa3d0e464823d73c2a28d50e11
  F src/pcache1.c 1195a21fe28e223e024f900b2011e80df53793f0356a24caace4188b098540dc
- F src/pragma.c 79ec7625d56130dbadf287a29b0ebf22167465049646366ad860a694f4547768
 -F src/pragma.c b5483eba1898652d330231164c17624a93e7a991b2f5c7e8a80f9d85528b308c
 -F src/pragma.h 37a1311d0388db480388d7ec09054f7103045eff20d4971f8a433b77f40b9921
 -F src/prepare.c b1140c3d0cf59bc85ace00ce363153041b424b7a
++F src/pragma.c 54e64a9d65e2c3b6ef11d4ca732c6abc8b67f5e886f222ffe2cbf3506c4efbd2
 +F src/pragma.h bb83728944b42f6d409c77f5838a8edbdb0fe83046c5496ffc9602b40340a324
 +F src/prepare.c 4b84ae7458febe1df3e04ae62ba56abc851f771340e460d14426e6802c5615f4
  F src/printf.c 8757834f1b54dae512fb25eb1acc8e94a0d15dd2290b58f2563f65973265adb2
  F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 -F src/resolve.c adf3ef9843135b1383321ad751f16f5a40c3f37925154555a3e61653d2a954e8
 +F src/resolve.c 6aa1fb1212e601f65b983ee1215d69a591986c8f97a3805c425c625a53839539
  F src/rowset.c 7b7e7e479212e65b723bf40128c7b36dc5afdfac
 -F src/select.c 0d2afdbdba5fbc61432c5454a35e0236e7aa4aa3756986a7d51b81a508e8083a
 -F src/shell.c bcd3358ad6cb3f3dc7ec76ad3bd8191f123ed2425360c5c48fe431780eceb729
 -F src/sqlite.h.in 67fa8bd29808e7988e0ce36c8d4c6043eb1727f94522fc612687aa5af51931e6
 +F src/select.c c9f7b7196e196e93979665680d055a789938b8e025556097bf484b184c0dd576
 +F src/shell.c a7067f647aef4b81569bbfd025f4fd120a4e7576a647d2aad05028eb50e50e48
 +F src/sqlite.h.in c38c31f2a874af2b7d8443aba1fba3652d8ee75f60305d2512215cbe0fa0674a
  F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
  F src/sqlite3ext.h 58fd0676d3111d02e62e5a35992a7d3da5d3f88753acc174f2d37b774fbbdd28
 -F src/sqliteInt.h 17e9bce594ea0c38c44ad0cbff4aa50cbff4b25f4bac9d38306caf9f1f028ac9
 +F src/sqliteInt.h 7a7cd6f682471cce4afe64216f71fd64c622712aeb9d947c33c38337a7cf19a9
  F src/sqliteLimit.h 1513bfb7b20378aa0041e7022d04acb73525de35b80b252f1b83fedb4de6a76b
  F src/status.c a9e66593dfb28a9e746cba7153f84d49c1ddc4b1
  F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
@@@ -1628,7 -1583,10 +1628,8 @@@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a9
  F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
  F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
  F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
- P 0961ec873b78ad2da0ea9cdf2934bc8f08276375a153fe5d9fa8d4280328deef
- R 79fe59dfa4a836939eb45a203b110400
 -P f3db02f49073c3f08c3fd7816d85e5472d5e22df20d862fe4886eb2a97efb15f
 -R bfe3d3db972c98c6ca95dc686a1c98c9
 -T *branch * fast-secure-delete
 -T *sym-fast-secure-delete *
 -T -sym-trunk *
++P 732f90d6327c5c6368fc8b4cc207bd644ef08e3ae6d2e7295258ab099deaba63 f1682f0faf1a93ded066464b1ddd5f987e21ee0f6bb5e828ed31c3ad903cf2c3
++R 1f238fbce697fb2308131c37c5985e85
++T +closed f1682f0faf1a93ded066464b1ddd5f987e21ee0f6bb5e828ed31c3ad903cf2c3
  U drh
- Z 8d02d118072fdff02038158664ac514a
 -Z 1665a7b13a5f9ef4377c01699ae7453e
++Z c2c4f30ab3360a9e7249032b4e3580ff

diff --cc manifest.uuid
index 375b8be127d80046f5d886a35db2d7ee2c6e9d6e,d384d6edc59be56808ea092b7582efef1b868373..bc0b488c810b0b4bcbd538f4b64f52a468238fa9
--- 1/manifest.uuid
--- 2/manifest.uuid
+++ b/manifest.uuid
@@@ -1,1 -1,1 +1,1 @@@
- 732f90d6327c5c6368fc8b4cc207bd644ef08e3ae6d2e7295258ab099deaba63
 -f1682f0faf1a93ded066464b1ddd5f987e21ee0f6bb5e828ed31c3ad903cf2c3
++38978ce65b280bb7cba3fc08ba91485fb1b84cd9fbba2e950ecf41c021ff452a

diff --cc src/btree.c
Simple merge

diff --cc src/pragma.c
Simple merge