Adding the sqlite sourcecode

ext/recover/recovercorrupt.test

@@ -0,0 +1,67 @@
+# 2022 August 28
+#
+# 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.
+#
+#***********************************************************************
+#
+
+source [file join [file dirname [info script]] recover_common.tcl]
+set testprefix recovercorrupt
+
+database_may_be_corrupt
+
+do_execsql_test 1.0 {
+  PRAGMA page_size = 512;
+  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
+  INSERT INTO t1 VALUES(1, 2, 3);
+  INSERT INTO t1 VALUES(2, hex(randomblob(100)), randomblob(200));
+  CREATE INDEX i1 ON t1(b, c);
+  CREATE TABLE t2(a PRIMARY KEY, b, c) WITHOUT ROWID;
+  INSERT INTO t2 VALUES(1, 2, 3);
+  INSERT INTO t2 VALUES(2, hex(randomblob(100)), randomblob(200));
+  ANALYZE;
+  PRAGMA writable_schema = 1;
+  DELETE FROM sqlite_schema WHERE name='t2';
+}
+
+do_test 1.1 {
+  expr [file size test.db]>3072
+} {1}
+
+proc toggle_bit {blob bit} {
+  set byte [expr {$bit / 8}]
+  set bit [expr {$bit & 0x0F}]
+  binary scan $blob a${byte}ca* A x B
+  set x [expr {$x ^ (1 << $bit)}]
+  binary format a*ca* $A $x $B
+}
+
+
+db_save_and_close
+for {set ii 0} {$ii < 10000} {incr ii} {
+  db_restore_and_reopen
+  db func toggle_bit toggle_bit
+  set bitsperpage [expr 512*8]
+
+  set pg [expr {($ii / $bitsperpage)+1}]
+  set byte [expr {$ii % $bitsperpage}]
+  db eval {
+    UPDATE sqlite_dbpage SET data = toggle_bit(data, $byte) WHERE pgno=$pg
+  }
+
+    set R [sqlite3_recover_init db main test.db2]
+    $R config lostandfound lost_and_found
+    $R run
+  do_test 1.2.$ii {
+    $R finish
+  } {}
+}
+
+
+finish_test
+