# 2005 March 18
#
# 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 file attempts to check that the library can recover from a malloc()
# failure when sqlite3_global_recover() is invoked.
#
# (Later:) The sqlite3_global_recover() interface is now a no-op.
# Recovery from malloc() failures is automatic.  But we keep these
# tests around because you can never have too many test cases.
#
# $Id: malloc2.test,v 1.6 2007/08/22 22:04:37 drh Exp $

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

# Only run these tests if memory debugging is turned on.
#
ifcapable !memdebug {
   puts "Skipping malloc tests: not compiled with -DSQLITE_MEMDEBUG..."
   finish_test
   return
}

# Generate a checksum based on the contents of the database. If the
# checksum of two databases is the same, and the integrity-check passes
# for both, the two databases are identical.
#
proc cksum {db} {
  set ret [list]
  ifcapable tempdb {
    set sql {
      SELECT name FROM sqlite_master WHERE type = 'table' UNION
      SELECT name FROM sqlite_temp_master WHERE type = 'table' UNION
      SELECT 'sqlite_master' UNION
      SELECT 'sqlite_temp_master'
    }
  } else {
    set sql {
      SELECT name FROM sqlite_master WHERE type = 'table' UNION
      SELECT 'sqlite_master'
    }
  }
  set tbllist [$db eval $sql]
  set txt {}
  foreach tbl $tbllist {
    append txt [$db eval "SELECT * FROM $tbl"]
  }
  # puts txt=$txt
  return [md5 $txt]
}

proc do_malloc2_test {tn args} {
  array set ::mallocopts $args
  set sum [cksum db]

  for {set ::n 1} {true} {incr ::n} {

    # Run the SQL. Malloc number $::n is set to fail. A malloc() failure
    # may or may not be reported.
    sqlite3_memdebug_fail $::n 1
    do_test malloc2-$tn.$::n.2 {
      set res [catchsql [string trim $::mallocopts(-sql)]]
      set rc [expr { 
        0==[string compare $res {1 {out of memory}}] ||
        0==[lindex $res 0]
      }]
      if {$rc!=1} {
        puts "Error: $res"
      }
      set rc
    } {1}

    # If $::n is greater than the number of malloc() calls required to
    # execute the SQL, then this test is finished. Break out of the loop.
    set nFail [sqlite3_memdebug_fail -1 -1]
    if {$nFail==0} break

    # Nothing should work now, because the allocator should refuse to
    # allocate any memory.
    #
    # Update: SQLite now automatically recovers from a malloc() failure.
    # So the statement in the test below would work. 
    if 0 {
      do_test malloc2-$tn.$::n.3 {
        catchsql {SELECT 'nothing should work'}
      } {1 {out of memory}}
    }

    # Recover from the malloc failure.
    #
    # Update: The new malloc() failure handling means that a transaction may
    # still be active even if a malloc() has failed. But when these tests were
    # written this was not the case. So do a manual ROLLBACK here so that the
    # tests pass.
    do_test malloc2-$tn.$::n.4 {
      sqlite3_global_recover
      catch {
        execsql {
          ROLLBACK;
        }
      }
      expr 0
    } {0}

    # Checksum the database.
    do_test malloc2-$tn.$::n.5 {
      cksum db
    } $sum

    integrity_check malloc2-$tn.$::n.6
    if {$::nErr>1} return
  }
  unset ::mallocopts
}

do_test malloc2.1.setup {
  execsql {
    CREATE TABLE abc(a, b, c);
    INSERT INTO abc VALUES(10, 20, 30);
    INSERT INTO abc VALUES(40, 50, 60);
    CREATE INDEX abc_i ON abc(a, b, c);
  }
} {}
do_malloc2_test 1.1 -sql {
  SELECT * FROM abc;
}
do_malloc2_test 1.2 -sql {
  UPDATE abc SET c = c+10;
}
do_malloc2_test 1.3 -sql {
  INSERT INTO abc VALUES(70, 80, 90);
}
do_malloc2_test 1.4 -sql {
  DELETE FROM abc;
}
do_test malloc2.1.5 {
  execsql {
    SELECT * FROM abc;
  }
} {}

do_test malloc2.2.setup {
  execsql {
    CREATE TABLE def(a, b, c);
    CREATE INDEX def_i1 ON def(a);
    CREATE INDEX def_i2 ON def(c);
    BEGIN;
  }
  for {set i 0} {$i<20} {incr i} {
    execsql {
    INSERT INTO def VALUES(randstr(300,300),randstr(300,300),randstr(300,300));
    }
  }
  execsql {
    COMMIT;
  }
} {}
do_malloc2_test 2 -sql {
  BEGIN;
  UPDATE def SET a = randstr(100,100) WHERE (oid%9)==0;
  INSERT INTO def SELECT * FROM def WHERE (oid%13)==0;

  CREATE INDEX def_i3 ON def(b);

  UPDATE def SET a = randstr(100,100) WHERE (oid%9)==1;
  INSERT INTO def SELECT * FROM def WHERE (oid%13)==1;

  CREATE TABLE def2 AS SELECT * FROM def;
  DROP TABLE def;
  CREATE TABLE def AS SELECT * FROM def2;
  DROP TABLE def2;

  DELETE FROM def WHERE (oid%9)==2;
  INSERT INTO def SELECT * FROM def WHERE (oid%13)==2;
  COMMIT;
}

ifcapable tempdb {
  do_test malloc2.3.setup {
    execsql {
      CREATE TEMP TABLE ghi(a, b, c);
      BEGIN;
    }
    for {set i 0} {$i<20} {incr i} {
      execsql {
      INSERT INTO ghi VALUES(randstr(300,300),randstr(300,300),randstr(300,300));
      }
    }
    execsql {
      COMMIT;
    }
  } {}
  do_malloc2_test 3 -sql {
    BEGIN;
    CREATE INDEX ghi_i1 ON ghi(a);
    UPDATE def SET a = randstr(100,100) WHERE (oid%2)==0;
    UPDATE ghi SET a = randstr(100,100) WHERE (oid%2)==0;
    COMMIT;
  }
}

############################################################################
# The test cases below are to increase the code coverage in btree.c and 
# pager.c of this test file. The idea is that each malloc() that occurs in
# these two source files should be made to fail at least once.
#
catchsql {
  DROP TABLE ghi;
}
do_malloc2_test 4.1 -sql {
  SELECT * FROM def ORDER BY oid ASC;
  SELECT * FROM def ORDER BY oid DESC;
}
do_malloc2_test 4.2 -sql {
  PRAGMA cache_size = 10;
  BEGIN;

  -- This will put about 25 pages on the free list.
  DELETE FROM def WHERE 1;

  -- Allocate 32 new root pages. This will exercise the 'extract specific 
  -- page from the freelist' code when in auto-vacuum mode (see the
  -- allocatePage() routine in btree.c).
  CREATE TABLE t1(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t2(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t3(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t4(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t5(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t6(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t7(a UNIQUE, b UNIQUE, c UNIQUE);
  CREATE TABLE t8(a UNIQUE, b UNIQUE, c UNIQUE);

  ROLLBACK;
}

########################################################################
# Test that the global linked list of database handles works. An assert()
# will fail if there is some problem.
do_test malloc2-5 {
  sqlite3 db1 test.db
  sqlite3 db2 test.db
  sqlite3 db3 test.db
  sqlite3 db4 test.db
  sqlite3 db5 test.db

  # Close the head of the list:
  db5 close
  
  # Close the end of the list:
  db1 close

  # Close a handle from the middle of the list:
  db3 close

  # Close the other two. Then open and close one more database, to make
  # sure the head of the list was set back to NULL.
  db2 close
  db4 close
  sqlite db1 test.db
  db1 close
} {}

########################################################################
# Check that if a statement is active sqlite3_global_recover doesn't reset
# the sqlite3_malloc_failed variable.
#
# Update: There is now no sqlite3_malloc_failed variable, so these tests 
# are not run.
#
# do_test malloc2-6.1 {
#   set ::STMT [sqlite3_prepare $::DB {SELECT * FROM def} -1 DUMMY]
#   sqlite3_step $::STMT
# } {SQLITE_ROW}
# do_test malloc2-6.2 {
#   sqlite3 db1 test.db
#   sqlite_malloc_fail 100
#   catchsql {
#     SELECT * FROM def;
#   } db1
# } {1 {out of memory}}
# do_test malloc2-6.3 {
#   sqlite3_global_recover
# } {SQLITE_BUSY}
# do_test malloc2-6.4 {
#   catchsql {
#     SELECT 'hello';
#   }
# } {1 {out of memory}}
# do_test malloc2-6.5 {
#   sqlite3_reset $::STMT
# } {SQLITE_OK}
# do_test malloc2-6.6 {
#   sqlite3_global_recover
# } {SQLITE_OK}
# do_test malloc2-6.7 {
#   catchsql {
#     SELECT 'hello';
#   }
# } {0 hello}
# do_test malloc2-6.8 {
#   sqlite3_step $::STMT
# } {SQLITE_ERROR}
# do_test malloc2-6.9 {
#   sqlite3_finalize $::STMT
# } {SQLITE_SCHEMA}
# do_test malloc2-6.10 {
#   db1 close
# } {}

########################################################################
# Check that if an in-memory database is being used it is not possible
# to recover from a malloc() failure.
#
# Update: An in-memory database can now survive a malloc() failure, so these
# tests are not run.
#
# ifcapable memorydb {
#   do_test malloc2-7.1 {
#     sqlite3 db1 :memory:
#     list
#   } {}
#   do_test malloc2-7.2 {
#     sqlite_malloc_fail 100
#     catchsql {
#       SELECT * FROM def;
#     } 
#   } {1 {out of memory}}
#   do_test malloc2-7.3 {
#     sqlite3_global_recover
#   } {SQLITE_ERROR}
#   do_test malloc2-7.4 {
#     catchsql {
#       SELECT 'hello';
#     }
#   } {1 {out of memory}}
#   do_test malloc2-7.5 {
#     db1 close
#   } {}
#   do_test malloc2-7.6 {
#     sqlite3_global_recover
#   } {SQLITE_OK}
#   do_test malloc2-7.7 {
#     catchsql {
#       SELECT 'hello';
#     }
#   } {0 hello}
# }

finish_test