SQLite

#undef sqlite3OsCheckReservedLock 

#define BLOCKSIZE 512
#define BLOCK_OFFSET(x) ((x) * BLOCKSIZE)


/*
** The following variables control when a simulated crash occurs.
**
** If iCrashDelay is non-zero, then zCrashFile contains (full path) name of
** a file that SQLite will call sqlite3OsSync() on. Each time this happens
** iCrashDelay is decremented. If iCrashDelay is zero after being
** decremented, a "crash" occurs during the sync() operation.
**
** In other words, a crash occurs the iCrashDelay'th time zCrashFile is
** synced.
*/
static int iCrashDelay = 0;
char zCrashFile[256];

/*
** Set the value of the two crash parameters.










*/
void sqlite3SetCrashParams(int iDelay, char const *zFile){
  sqlite3OsEnterMutex();
  assert( strlen(zFile)<256 );
  strcpy(zCrashFile, zFile);
  iCrashDelay = iDelay;
  sqlite3OsLeaveMutex();
}


/*
** File zPath is being sync()ed. Return non-zero if this should
** cause a crash.
*/
static int crashRequired(char const *zPath){
  int r;
  int n;
  sqlite3OsEnterMutex();
  n = strlen(zCrashFile);
  if( zCrashFile[n-1]=='*' ){
    n--;
  }else if( strlen(zPath)>n ){
    n = strlen(zPath);
  }
  r = ( 
    iCrashDelay>0 &&
    !strncmp(zPath, zCrashFile, n) &&
    --iCrashDelay==0
  )?1:0;
  sqlite3OsLeaveMutex();
  return r;
}


static OsTestFile *pAllFiles = 0;

/*
** Initialise the os_test.c specific fields of pFile.
*/
static void initFile(OsFile *id, char const *zName){

      if( rc!=SQLITE_OK ) return rc;
    }
  }

  return SQLITE_OK;
}

/* #define TRACE_WRITECACHE  */

/*
** Write the cache of pFile to disk. If crash is non-zero, randomly
** skip blocks when writing. The cache is deleted before returning.
*/
static int writeCache2(OsTestFile *pFile, int crash){
  int i;
  int nMax = pFile->nMaxWrite;
  off_t offset;
  int rc = SQLITE_OK;

  offset = osTell(pFile);
  for(i=0; i<pFile->nBlk; i++){
    u8 *p = pFile->apBlk[i];
    if( p ){
      int skip = 0;
      if( crash ){
        char random;
        sqlite3Randomness(1, &random);
        if( random & 0x01 ){
          skip = 1;

#ifdef TRACE_WRITECACHE
printf("Not writing block %d of %s\n", i, pFile->zName); 

        }else{

printf("Writing block %d of %s\n", i, pFile->zName); 

#endif
        }
      }

      if( rc==SQLITE_OK ){
        rc = sqlite3RealSeek(&pFile->fd, BLOCK_OFFSET(i));
      }
      if( rc==SQLITE_OK && !skip ){
        int len = BLOCKSIZE;
        if( BLOCK_OFFSET(i+1)>nMax ){
          len = nMax-BLOCK_OFFSET(i);

  return rc;
}

/*
** Write the cache to disk.
*/
static int writeCache(OsTestFile *pFile){
  if( pFile->apBlk ){
    int c = crashRequired(pFile->zName);
    if( c ){

      OsTestFile *p;
#ifdef TRACE_WRITECACHE
      printf("Crash during sync of %s\n", pFile->zName);
#endif
      for(p=pAllFiles; p; p=p->pNext){
        writeCache2(p, 1);
      }
      exit(-1);
    }else{

      return writeCache2(pFile, 0);
    }
  }
  return SQLITE_OK;
}

/*
** Close the file.
*/
int sqlite3OsClose(OsFile *id){
  if( !(*id) ) return SQLITE_OK;

  int nBlk;         /* Size of apBlock. */
  int nMaxWrite;    /* Largest offset written to. */
  char *zName;      /* File name */
  OsRealFile fd;
  OsTestFile *pNext;
};

void sqlite3SetCrashParams(int iDelay, char const *zFile);

#endif /* _SQLITE_OS_UNIX_H_ */

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.137 2004/06/23 10:43:10 danielk1977 Exp $
*/
#include "os.h"         /* Must be first to enable large file support */
#include "sqliteInt.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

    sqliteFree( pPager->aInJournal );
    pPager->aInJournal = 0;
    for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
      pPg->inJournal = 0;
      pPg->dirty = 0;
      pPg->needSync = 0;
    }
    pPager->dirtyCache = 0;
    pPager->nMaster = 0;
    pPager->nRec = 0;
  }else{
    assert( pPager->dirtyCache==0 || pPager->useJournal==0 );
  }
  sqlite3OsUnlock(&pPager->fd, SHARED_LOCK);
  pPager->state = PAGER_SHARED;
  pPager->origDbSize = 0;
  return SQLITE_OK;
}

/*
** Compute and return a checksum for the page of data.
**
** This is not a real checksum.  It is really just the sum of the 

**
** FIX ME:  Consider adding every 200th (or so) byte of the data to the
** checksum.  That way if a single page spans 3 or more disk sectors and
** only the middle sector is corrupt, we will still have a reasonable
** chance of failing the checksum and thus detecting the problem.
*/
static u32 pager_cksum(Pager *pPager, Pgno pgno, const char *aData){
  u32 cksum = pPager->cksumInit;
  int i = pPager->pageSize-200;
  while( i>0 ){
    cksum += aData[i];
    i -= 200;
  }
  return cksum;
}

/*
** Read a single page from the journal file opened on file descriptor
** jfd.  Playback this one page.
**

  if( rc!=SQLITE_OK || memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
    goto end_playback;
  }

  /* (2) Read the number of pages stored in the journal.  */
  rc = read32bits(&pPager->jfd, (u32*)&nRec);
  if( rc ) goto end_playback;
  if( nRec==0xffffffff || useJournalSize || 
      nRec>(szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager)
  ){
    nRec = (szJ - JOURNAL_HDR_SZ(pPager))/JOURNAL_PG_SZ(pPager);
  }

  /* (3) Read the initial value for the sanity checksum */
  rc = read32bits(&pPager->jfd, &pPager->cksumInit);
  if( rc ) goto end_playback;

    if( pPager->noSync ) pPager->needSync = 0; 
  }else{
    pPager->noSync = 1;
    mxPage = -mxPage;
  }
  if( mxPage>10 ){
    pPager->mxPage = mxPage;
  }else{
    pPager->mxPage = 10;
  }
}

/*
** Adjust the robustness of the database to damage due to OS crashes
** or power failures by changing the number of syncs()s when writing
** the rollback journal.  There are three levels:

    ** if there have been no changes to the database file. */
    assert( pPager->needSync==0 );
    rc = pager_unwritelock(pPager);
    pPager->dbSize = -1;
    return rc;
  }
  assert( pPager->journalOpen );













  rc = sqlite3pager_sync(pPager, 0);
  if( rc!=SQLITE_OK ){
    goto commit_abort;
  }
  rc = pager_unwritelock(pPager);
  pPager->dbSize = -1;
  return rc;

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the printf() interface to SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.84 2004/06/23 10:43:11 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

bad_args:
  Tcl_AppendResult(interp, "wrong # args: should be \"",
      Tcl_GetStringFromObj(objv[0], 0), " <DB> <utf8> <utf16le> <utf16be>", 0);
  return TCL_ERROR;
}

static int sqlite3_crashparams(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
#ifdef OS_TEST
  int delay;
  if( objc!=3 ) goto bad_args;
  if( Tcl_GetIntFromObj(interp, objv[1], &delay) ) return TCL_ERROR;
  sqlite3SetCrashParams(delay, Tcl_GetString(objv[2]));
#endif
  return TCL_OK;

#ifdef OS_TEST
bad_args:
  Tcl_AppendResult(interp, "wrong # args: should be \"",
      Tcl_GetStringFromObj(objv[0], 0), "<delay> <filename>", 0);
  return TCL_ERROR;
#endif
}


/*
** Usage:    breakpoint

     /* Functions from os.h */
     { "sqlite3OsOpenReadWrite",test_sqlite3OsOpenReadWrite, 0 },
     { "sqlite3OsClose",        test_sqlite3OsClose, 0 },
     { "sqlite3OsLock",         test_sqlite3OsLock, 0 },
     { "sqlite3OsUnlock",       test_sqlite3OsUnlock, 0 },
     { "add_test_collate",      test_collate, 0         },
     { "sqlite3_crashparams",     sqlite3_crashparams, 0         },

  };
  int i;
  extern int sqlite3_os_trace;

  for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){
    Tcl_CreateCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0);

# 2001 September 15
#
# 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 implements regression tests for SQLite library.
#
# $Id: crash.test,v 1.3 2004/06/23 10:43:15 danielk1977 Exp $

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

set repeats 100
# set repeats 5

# This proc execs a seperate process that crashes midway through executing
# the SQL script $sql on database test.db.
#
# The crash occurs during a sync() of file $crashfile. When the crash
# occurs a random subset of all unsynced writes made by the process are
# written into the files on disk. Argument $crashdelay indicates the
# number of file syncs to wait before crashing.
#
# The return value is a list of two elements. The first element is a
# boolean, indicating whether or not the process actually crashed or
# reported some other error. The second element in the returned list is the
# error message. This is "child process exited abnormally" if the crash
# occured.
proc crashsql {crashdelay crashfile sql} {
  set cfile [file join [pwd] $crashfile]

  set f [open crash.tcl w]
  puts $f "sqlite3_crashparams $crashdelay $cfile"
  puts $f "sqlite3 db test.db"
  puts $f "db eval {pragma full_synchronous = 1}"
  puts $f "db eval {"
  puts $f   "$sql"
  puts $f "}"
  close $f

  set r [catch {
    exec [file join . crashtest] crash.tcl
  } msg]
  lappend r $msg
}

# The following procedure computes a "signature" for table "abc".  If
# abc changes in any way, the signature should change.  
proc signature {} {
  return [db eval {SELECT count(*), md5sum(a), md5sum(b), md5sum(c) FROM abc}]
}
proc signature2 {} {
  return [db eval {SELECT count(*), md5sum(a), md5sum(b), md5sum(c) FROM abc2}]
}

# Use a small pager-cache for these tests.
do_test crash-0.1 {
  execsql { pragma default_cache_size = 10 }
} {}

#--------------------------------------------------------------------------
# Simple crash test:
#
# crash-1.1: Create a database with a table with two rows.
# crash-1.2: Run a 'DELETE FROM abc WHERE a = 1' that crashes during
#            the first journal-sync.
# crash-1.3: Ensure the database is in the same state as after crash-1.1.
# crash-1.4: Run a 'DELETE FROM abc WHERE a = 1' that crashes during
#            the first database-sync.
# crash-1.5: Ensure the database is in the same state as after crash-1.1.
#
# Tests 1.6 through 1.9 are the same as 1.2 through 1.5, except the crash
# is requested on the second sync of each file. This doesn't happen in
# such a small test case, so these tests are just to verify that the
# test infrastructure operates as expected.
#
do_test crash-1.1 {
  execsql {
    CREATE TABLE abc(a, b, c);
    INSERT INTO abc VALUES(1, 2, 3);
    INSERT INTO abc VALUES(4, 5, 6);
  }
  set ::sig [signature]
  expr 0
} {0}
do_test crash-1.2 {

  crashsql 1 test.db-journal {
    DELETE FROM abc WHERE a = 1;
  }
} {1 {child process exited abnormally}}

# exit

do_test crash-1.3 {
  signature
} $::sig
do_test crash-1.4 {
  crashsql 1 test.db {
    DELETE FROM abc WHERE a = 1;
  }
} {1 {child process exited abnormally}}
do_test crash-1.5 {
  signature
} $::sig
do_test crash-1.6 {
  crashsql 2 test.db-journal {
    DELETE FROM abc WHERE a = 1;
  }
} {0 {}}
do_test crash-1.7 {
  catchsql {
    SELECT * FROM abc;
  }
} {0 {4 5 6}}
do_test crash-1.8 {
  crashsql 2 test.db {
    DELETE FROM abc WHERE a = 4;
  }
} {0 {}}
do_test crash-1.9 {
  catchsql {
    SELECT * FROM abc;
  }
} {0 {}}

#--------------------------------------------------------------------------
# The following tests test recovery when both the database file and the the
# journal file contain corrupt data. This can happen after pages are
# written to the database file before a transaction is committed due to
# cache-pressure.
#
# crash-2.1: Insert 18 pages of data into the database.
# crash-2.2: Check the database file size looks ok.
# crash-2.3: Delete 15 or so pages (with a 10 page page-cache), then crash.
# crash-2.4: Ensure the database is in the same state as after crash-2.1.
#
# Test cases crash-2.5 and crash-2.6 check that the database is OK if the 
# crash occurs during the main database file sync. But this isn't really
# different from the crash-1.* cases.
#
do_test crash-2.1 {
  execsql { BEGIN }
  for {set n 0} {$n < 1000} {incr n} {
    execsql "INSERT INTO abc VALUES($n, [expr 2*$n], [expr 3*$n])"
  }
  execsql { COMMIT }
  set ::sig [signature]
  execsql { SELECT sum(a), sum(b), sum(c) from abc }
} {499500 999000 1498500}
do_test crash-2.2 {
  expr [file size test.db] / 1024
} {19}
do_test crash-2.3 {
  crashsql 2 test.db-journal {
    DELETE FROM abc WHERE a < 800;
  }
} {1 {child process exited abnormally}}
do_test crash-2.4 {
  signature
} $sig
do_test crash-2.5 {
  crashsql 1 test.db {
    DELETE FROM abc WHERE a<800;
  }
} {1 {child process exited abnormally}}
do_test crash-2.6 {
  signature
} $sig

#--------------------------------------------------------------------------
# The crash-3.* test cases are essentially the same test as test case
# crash-2.*, but with a more complicated data set. 
#
# The test is repeated a few times with different seeds for the random
# number generator in the crashing executable. Because there is no way to
# seed the random number generator directly, some SQL is added to the test
# case to 'use up' a different quantity random numbers before the test SQL
# is executed.
#

# Make sure the file is much bigger than the pager-cache (10 pages). This
# ensures that cache-spills happen regularly.
do_test crash-3.0 {
  execsql {
    INSERT INTO abc SELECT * FROM abc;
    INSERT INTO abc SELECT * FROM abc;
    INSERT INTO abc SELECT * FROM abc;
    INSERT INTO abc SELECT * FROM abc;
    INSERT INTO abc SELECT * FROM abc;
  }
  expr [file size test.db] / 1024
} {554}
for {set i 1} {$i < $repeats} {incr i} {
  set sig [signature]
  do_test crash-3.$i.1 {
     crashsql [expr $i%5 + 1] test.db-journal "
       BEGIN;
       SELECT random() FROM abc LIMIT $i;
       INSERT INTO abc VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc WHERE random()%10!=0;
       COMMIT;
     "
  } {1 {child process exited abnormally}}
  do_test crash-3.$i.2 {
    signature
  } $sig
} 



#--------------------------------------------------------------------------
# The following test cases - crash-4.* - test the correct recovery of the
# database when a crash occurs during a multi-file transaction.
#
# crash-4.1.*: Test recovery when crash occurs during sync() of the 
#              main database journal file.
# crash-4.2.*: Test recovery when crash occurs during sync() of an 
#              attached database journal file.
# crash-4.3.*: Test recovery when crash occurs during sync() of the master
#              journal file. 
#
do_test crash-4.0 {
  file delete -force test2.db
  file delete -force test2.db-journal
  sqlite3 db2 test2.db
  execsql {pragma default_cache_size = 10} db2
  db2 close
  execsql {
    ATTACH 'test2.db' AS aux;
    CREATE TABLE aux.abc2 AS SELECT 2*a as a, 2*b as b, 2*c as c FROM abc;
  }
  expr [file size test2.db] / 1024
} {559}

for {set i 1} {$i < $repeats} {incr i} {
  set sig [signature]
  set sig2 [signature2]
  do_test crash-4.1.$i.1 {
     crashsql [expr $i%5 + 1] test.db-journal "
       ATTACH 'test2.db' AS aux;
       BEGIN;
       SELECT random() FROM abc LIMIT $i;
       INSERT INTO abc VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc WHERE random()%10!=0;
       INSERT INTO abc2 VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc2 WHERE random()%10!=0;
       COMMIT;
     "
  } {1 {child process exited abnormally}}
  do_test crash-4.1.$i.2 {
    signature
  } $sig
  do_test crash-4.1.$i.3 {
    signature2
  } $sig2
} 
for {set i 1} {$i < $repeats} {incr i} {
  set sig [signature]
  set sig2 [signature2]
  do_test crash-4.2.$i.1 {
     crashsql [expr $i%5 + 1] test2.db-journal "
       ATTACH 'test2.db' AS aux;
       BEGIN;
       SELECT random() FROM abc LIMIT $i;
       INSERT INTO abc VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc WHERE random()%10!=0;
       INSERT INTO abc2 VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc2 WHERE random()%10!=0;
       COMMIT;
     "
  } {1 {child process exited abnormally}}
  do_test crash-4.2.$i.2 {
    signature
  } $sig
  do_test crash-4.2.$i.3 {
    signature2
  } $sig2
} 
for {set i 1} {$i < 5} {incr i} {
  set sig [signature]
  set sig2 [signature2]
  do_test crash-4.3.$i.1 {
     crashsql 1 test.db-mj* "
       ATTACH 'test2.db' AS aux;
       BEGIN;
       SELECT random() FROM abc LIMIT $i;
       INSERT INTO abc VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc WHERE random()%10!=0;
       INSERT INTO abc2 VALUES(randstr(10,10), 0, 0);
       DELETE FROM abc2 WHERE random()%10!=0;
       COMMIT;
     "
  } {1 {child process exited abnormally}}
  do_test crash-4.3.$i.2 {
    signature
  } $sig
  do_test crash-4.3.$i.3 {
    signature2
  } $sig2
}

finish_test