# 2009 January 8
#
# 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.
#
#***********************************************************************
#
# This test verifies a couple of specific potential data corruption 
# scenarios involving crashes or power failures.
#
# Later: Also, some other specific scenarios required for coverage
# testing that do not lead to corruption.
#
# $Id: crash8.test,v 1.4 2009/01/11 00:44:48 drh Exp $


set testdir [file dirname $argv0]
source $testdir/tester.tcl

ifcapable !crashtest {
  finish_test
  return
}
do_not_use_codec

do_test crash8-1.1 {
  execsql {
    PRAGMA auto_vacuum=OFF;
    CREATE TABLE t1(a, b);
    CREATE INDEX i1 ON t1(a, b);
    INSERT INTO t1 VALUES(1, randstr(1000,1000));
    INSERT INTO t1 VALUES(2, randstr(1000,1000));
    INSERT INTO t1 VALUES(3, randstr(1000,1000));
    INSERT INTO t1 VALUES(4, randstr(1000,1000));
    INSERT INTO t1 VALUES(5, randstr(1000,1000));
    INSERT INTO t1 VALUES(6, randstr(1000,1000));
    CREATE TABLE t2(a, b);
    CREATE TABLE t3(a, b);
    CREATE TABLE t4(a, b);
    CREATE TABLE t5(a, b);
    CREATE TABLE t6(a, b);
    CREATE TABLE t7(a, b);
    CREATE TABLE t8(a, b);
    CREATE TABLE t9(a, b);
    CREATE TABLE t10(a, b);
    PRAGMA integrity_check
  }
} {ok}


# Potential corruption scenario 1. A second process opens the database 
# and modifies a large portion of it. It then opens a second transaction
# and modifies a small part of the database, but crashes before it commits
# the transaction. 
#
# When the first process accessed the database again, it was rolling back
# the aborted transaction, but was not purging its in-memory cache (which
# was loaded before the second process made its first, successful, 
# modification). Producing an inconsistent cache.
#
do_test crash8-1.2 {
  crashsql -delay 2 -file test.db {
    PRAGMA cache_size = 10;
    UPDATE t1 SET b = randstr(1000,1000);
    INSERT INTO t9 VALUES(1, 2);
  }
} {1 {child process exited abnormally}}
do_test crash8-1.3 {
  execsql {PRAGMA integrity_check}
} {ok}

# Potential corruption scenario 2. The second process, operating in
# persistent-journal mode, makes a large change to the database file
# with a small in-memory cache. Such that more than one journal-header
# was written to the file. It then opens a second transaction and makes
# a smaller change that requires only a single journal-header to be
# written to the journal file. The second change is such that the 
# journal content written to the persistent journal file exactly overwrites
# the first journal-header and set of subsequent records written by the
# first, successful, change. The second process crashes before it can
# commit its second change.
#
# When the first process accessed the database again, it was rolling back
# the second aborted transaction, then continuing to rollback the second
# and subsequent journal-headers written by the first, successful, change.
# Database corruption.
#
do_test crash8.2.1 {
  crashsql -delay 2 -file test.db {
    PRAGMA journal_mode = persist;
    PRAGMA cache_size = 10;
    UPDATE t1 SET b = randstr(1000,1000);
    PRAGMA cache_size = 100;
    BEGIN;
      INSERT INTO t2 VALUES('a', 'b');
      INSERT INTO t3 VALUES('a', 'b');
      INSERT INTO t4 VALUES('a', 'b');
      INSERT INTO t5 VALUES('a', 'b');
      INSERT INTO t6 VALUES('a', 'b');
      INSERT INTO t7 VALUES('a', 'b');
      INSERT INTO t8 VALUES('a', 'b');
      INSERT INTO t9 VALUES('a', 'b');
      INSERT INTO t10 VALUES('a', 'b');
    COMMIT;
  }
} {1 {child process exited abnormally}}

do_test crash8-2.3 {
  execsql {PRAGMA integrity_check}
} {ok}

proc read_file {zFile} {
  set fd [open $zFile]
  fconfigure $fd -translation binary 
  set zData [read $fd]
  close $fd
  return $zData
}
proc write_file {zFile zData} {
  set fd [open $zFile w]
  fconfigure $fd -translation binary 
  puts -nonewline $fd $zData
  close $fd
}

# The following tests check that SQLite will not roll back a hot-journal
# file if the sector-size field in the first journal file header is
# suspect. Definition of suspect:
# 
#    a) Not a power of 2, or                (crash8-3.5)
#    b) Greater than 0x01000000 (16MB), or  (crash8-3.6)
#    c) Less than 512.                      (crash8-3.7)
#
# Also test that SQLite will not rollback a hot-journal file with a
# suspect page-size. In this case "suspect" means:
# 
#    a) Not a power of 2, or
#    b) Less than 512, or
#    c) Greater than SQLITE_MAX_PAGE_SIZE
#
do_test crash8-3.1 {
  list [file exists test.db-joural] [file exists test.db]
} {0 1}
do_test crash8-3.2 {
  execsql {
    PRAGMA synchronous = off;
    BEGIN;
    DELETE FROM t1;
    SELECT count(*) FROM t1;
  }
} {0}
do_test crash8-3.3 {
  set zJournal [read_file test.db-journal]
  execsql { 
    COMMIT;
    SELECT count(*) FROM t1;
  }
} {0}
do_test crash8-3.4 {
  binary scan [string range $zJournal 20 23] I nSector
  set nSector
} {512}

do_test crash8-3.5 {
  set zJournal2 [string replace $zJournal 20 23 [binary format I 513]]
  write_file test.db-journal $zJournal2

  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}
do_test crash8-3.6 {
  set zJournal2 [string replace $zJournal 20 23 [binary format I 0x2000000]]
  write_file test.db-journal $zJournal2
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}
do_test crash8-3.7 {
  set zJournal2 [string replace $zJournal 20 23 [binary format I 256]]
  write_file test.db-journal $zJournal2
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}

do_test crash8-3.8 {
  set zJournal2 [string replace $zJournal 24 27 [binary format I 513]]
  write_file test.db-journal $zJournal2

  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}
do_test crash8-3.9 {
  set big [expr $SQLITE_MAX_PAGE_SIZE * 2]
  set zJournal2 [string replace $zJournal 24 27 [binary format I $big]]
  write_file test.db-journal $zJournal2
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}
do_test crash8-3.10 {
  set zJournal2 [string replace $zJournal 24 27 [binary format I 256]]
  write_file test.db-journal $zJournal2
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {0 ok}

do_test crash8-3.11 {
  set fd [open test.db-journal w]
  fconfigure $fd -translation binary 
  puts -nonewline $fd $zJournal
  close $fd
  execsql { 
    SELECT count(*) FROM t1;
    PRAGMA integrity_check
  }
} {6 ok}


# If a connection running in persistent-journal mode is part of a 
# multi-file transaction, it must ensure that the master-journal name
# appended to the journal file contents during the commit is located
# at the end of the physical journal file. If there was already a
# large journal file allocated at the start of the transaction, this
# may mean truncating the file so that the master journal name really
# is at the physical end of the file.
#
# This block of tests test that SQLite correctly truncates such
# journal files, and that the results behave correctly if a hot-journal
# rollback occurs.
#
ifcapable pragma {
  reset_db
  forcedelete test2.db

  do_test crash8-4.1 {
    execsql {
      PRAGMA journal_mode = persist;
      CREATE TABLE ab(a, b);
      INSERT INTO ab VALUES(0, 'abc');
      INSERT INTO ab VALUES(1, NULL);
      INSERT INTO ab VALUES(2, NULL);
      INSERT INTO ab VALUES(3, NULL);
      INSERT INTO ab VALUES(4, NULL);
      INSERT INTO ab VALUES(5, NULL);
      INSERT INTO ab VALUES(6, NULL);
      UPDATE ab SET b = randstr(1000,1000);
      ATTACH 'test2.db' AS aux;
      PRAGMA aux.journal_mode = persist;
      CREATE TABLE aux.ab(a, b);
      INSERT INTO aux.ab SELECT * FROM main.ab;

      UPDATE aux.ab SET b = randstr(1000,1000) WHERE a>=1;
      UPDATE ab SET b = randstr(1000,1000) WHERE a>=1;
    }
    list [file exists test.db-journal] [file exists test2.db-journal]
  } {1 1}

  do_test crash8-4.2 {
    execsql {
      BEGIN;
        UPDATE aux.ab SET b = 'def' WHERE a = 0;
        UPDATE main.ab SET b = 'def' WHERE a = 0;
      COMMIT;
    }
  } {}

  do_test crash8-4.3 {
    execsql {
      UPDATE aux.ab SET b = randstr(1000,1000) WHERE a>=1;
      UPDATE ab SET b = randstr(1000,1000) WHERE a>=1;
    }
  } {}

  set contents_main [db eval {SELECT b FROM main.ab WHERE a = 1}]
  set contents_aux  [db eval {SELECT b FROM  aux.ab WHERE a = 1}]

  do_test crash8-4.4 {
    crashsql -file test2.db -delay 1 {
      ATTACH 'test2.db' AS aux;
      BEGIN;
        UPDATE aux.ab SET b = 'ghi' WHERE a = 0;
        UPDATE main.ab SET b = 'ghi' WHERE a = 0;
      COMMIT;
    }
  } {1 {child process exited abnormally}}

  do_test crash8-4.5 {
    list [file exists test.db-journal] [file exists test2.db-journal]
  } {1 1}

  do_test crash8-4.6 {
    execsql {
      SELECT b FROM main.ab WHERE a = 0;
      SELECT b FROM aux.ab WHERE a = 0;
    }
  } {def def}

  do_test crash8-4.7 {
    crashsql -file test2.db -delay 1 {
      ATTACH 'test2.db' AS aux;
      BEGIN;
        UPDATE aux.ab SET b = 'jkl' WHERE a = 0;
        UPDATE main.ab SET b = 'jkl' WHERE a = 0;
      COMMIT;
    }
  } {1 {child process exited abnormally}}

  do_test crash8-4.8 {
    set fd [open test.db-journal]
    fconfigure $fd -translation binary
    seek $fd -16 end
    binary scan [read $fd 4] I len

    seek $fd [expr {-1 * ($len + 16)}] end
    set zMasterJournal [read $fd $len]
    close $fd

    file exists $zMasterJournal
  } {1}

  do_test crash8-4.9 {
    execsql { SELECT b FROM aux.ab WHERE a = 0 }
  } {def}

  do_test crash8-4.10 {
    delete_file $zMasterJournal
    execsql { SELECT b FROM main.ab WHERE a = 0 }
  } {jkl}
}

#
# Since the following tests (crash8-5.*) rely upon being able
# to copy a file while open, they will not work on Windows.
#
if {$::tcl_platform(platform)=="unix"} {
  for {set i 1} {$i < 10} {incr i} {
    catch { db close }
    forcedelete test.db test.db-journal
    sqlite3 db test.db
    do_test crash8-5.$i.1 {
      execsql {
        CREATE TABLE t1(x PRIMARY KEY);
        INSERT INTO t1 VALUES(randomblob(900));
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;          /* 64 rows */
      }
      crashsql -file test.db -delay [expr ($::i%2) + 1] {
        PRAGMA cache_size = 10;
        BEGIN;
          UPDATE t1 SET x = randomblob(900);
        ROLLBACK;
        INSERT INTO t1 VALUES(randomblob(900));
      }
      execsql { PRAGMA integrity_check }
    } {ok}
  
    catch { db close }
    forcedelete test.db test.db-journal
    sqlite3 db test.db
    do_test crash8-5.$i.2 {
      execsql {
        PRAGMA cache_size = 10;
        CREATE TABLE t1(x PRIMARY KEY);
        INSERT INTO t1 VALUES(randomblob(900));
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;
        INSERT INTO t1 SELECT randomblob(900) FROM t1;          /* 64 rows */
        BEGIN;
          UPDATE t1 SET x = randomblob(900);
      }
      forcedelete testX.db testX.db-journal testX.db-wal
      forcecopy test.db testX.db
      forcecopy test.db-journal testX.db-journal
      db close

      crashsql -file test.db -delay [expr ($::i%2) + 1] {
        SELECT * FROM sqlite_master;
        INSERT INTO t1 VALUES(randomblob(900));
      }

      sqlite3 db2 testX.db
      execsql { PRAGMA integrity_check } db2
    } {ok}
  }
  catch {db2 close}
}

finish_test