SQLite

/*
** If we compile with the SQLITE_TEST macro set, then the following block
** of code will give us the ability to simulate a disk I/O error.  This
** is used for testing the I/O recovery logic.
*/
#ifdef SQLITE_TEST
int sqlite3_io_error_hit = 0;
int sqlite3_io_error_pending = 0;
int sqlite3_diskfull_pending = 0;
int sqlite3_diskfull = 0;
#define SimulateIOError(A)  \
   if( sqlite3_io_error_pending ) \
     if( sqlite3_io_error_pending-- == 1 ){ local_ioerr(); return A; }
static void local_ioerr(){
  sqlite3_io_error_hit = 1;  /* Really just a place to set a breakpoint */
}
#define SimulateDiskfullError \
   if( sqlite3_diskfull_pending ){ \
     if( sqlite3_diskfull_pending == 1 ){ \
       local_ioerr(); \
       sqlite3_diskfull = 1; \
       return SQLITE_FULL; \

** 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 1.216 2005/11/04 22:03:30 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

  assert( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE );
  if( !pPager->memDb ){
    pPager->pageSize = pageSize;
  }
  return pPager->pageSize;
}

/*
** The following set of routines are used to disable the simulated
** I/O error mechanism.  These routines are used to avoid simulated
** errors in places where we do not care about errors.
**
** Unless -DSQLITE_TEST=1 is used, these routines are all no-ops
** and generate no code.
*/
#ifdef SQLITE_TEST
extern int sqlite3_io_error_pending;
extern int sqlite3_io_error_hit;
static int saved_cnt;
void clear_simulated_io_error(){
  sqlite3_io_error_hit = 0;
}
void disable_simulated_io_errors(void){
  saved_cnt = sqlite3_io_error_pending;
  sqlite3_io_error_pending = -1;
}
void enable_simulated_io_errors(void){
  sqlite3_io_error_pending = saved_cnt;
}
#else
# define clear_simulated_io_error(X)
# define disable_simulated_io_errors(X)
# define enable_simulated_io_errors(X)
#endif

/*
** Read the first N bytes from the beginning of the file into memory
** that pDest points to.  No error checking is done.
*/
void sqlite3pager_read_fileheader(Pager *pPager, int N, unsigned char *pDest){
  memset(pDest, 0, N);
  if( MEMDB==0 ){
    sqlite3OsSeek(&pPager->fd, 0);
    sqlite3OsRead(&pPager->fd, pDest, N);
    clear_simulated_io_error();
  }
}

/*
** Return the total number of pages in the disk file associated with
** pPager. 
**

    case PAGER_RESERVED:
    case PAGER_SYNCED: 
    case PAGER_EXCLUSIVE: {
      /* We ignore any IO errors that occur during the rollback
      ** operation. So disable IO error simulation so that testing
      ** works more easily.
      */



      disable_simulated_io_errors();

      sqlite3pager_rollback(pPager);

      enable_simulated_io_errors();

      if( !MEMDB ){
        sqlite3OsUnlock(&pPager->fd, NO_LOCK);
      }
      assert( pPager->errMask || pPager->journalOpen==0 );
      break;
    }
    case PAGER_SHARED: {

      if( rc!=SQLITE_OK ){
        i64 fileSize;
        if( sqlite3OsFileSize(&pPager->fd,&fileSize)!=SQLITE_OK
               || fileSize>=pgno*pPager->pageSize ){
          sqlite3pager_unref(PGHDR_TO_DATA(pPg));
          return rc;
        }else{
          clear_simulated_io_error();
          memset(PGHDR_TO_DATA(pPg), 0, pPager->pageSize);
        }
      }else{
        TEST_INCR(pPager->nRead);
      }
    }
#ifdef SQLITE_CHECK_PAGES

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the pager.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test2.c,v 1.35 2005/11/04 22:03:30 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

#endif

/*
** Register commands with the TCL interpreter.
*/
int Sqlitetest2_Init(Tcl_Interp *interp){
  extern int sqlite3_io_error_pending;
  extern int sqlite3_io_error_hit;
  extern int sqlite3_diskfull_pending;
  extern int sqlite3_diskfull;
  static struct {
    char *zName;
    Tcl_CmdProc *xProc;
  } aCmd[] = {
    { "pager_open",              (Tcl_CmdProc*)pager_open          },

  };
  int i;
  for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){
    Tcl_CreateCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0);
  }
  Tcl_LinkVar(interp, "sqlite_io_error_pending",
     (char*)&sqlite3_io_error_pending, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_io_error_hit",
     (char*)&sqlite3_io_error_hit, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_diskfull_pending",
     (char*)&sqlite3_diskfull_pending, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_diskfull",
     (char*)&sqlite3_diskfull, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_pending_byte",
     (char*)&sqlite3_pending_byte, TCL_LINK_INT);
  Tcl_LinkVar(interp, "pager_pagesize",
     (char*)&test_pagesize, TCL_LINK_INT);
  return TCL_OK;
}

**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.47 2005/11/04 22:03:30 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"

#ifndef SQLITE_OMIT_VACUUM
/*
** Generate a random name of 20 character in length.

#ifndef SQLITE_OMIT_VACUUM
  const char *zFilename;  /* full pathname of the database file */
  int nFilename;          /* number of characters  in zFilename[] */
  char *zTemp = 0;        /* a temporary file in same directory as zFilename */
  Btree *pMain;           /* The database being vacuumed */
  Btree *pTemp;
  char *zSql = 0;
  int rc2;  
  int saved_flags;       /* Saved value of the db->flags */

  /* Save the current value of the write-schema flag before setting it. */
  saved_flags = db->flags;
  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;

  if( !db->autoCommit ){

  execSql(db, "PRAGMA vacuum_db.synchronous=OFF");

#ifndef SQLITE_OMIT_AUTOVACUUM
  sqlite3BtreeSetAutoVacuum(pTemp, sqlite3BtreeGetAutoVacuum(pMain));
#endif

  /* Begin a transaction */
  rc = execSql(db, "BEGIN EXCLUSIVE;");
  if( rc!=SQLITE_OK ) goto end_of_vacuum;

  /* Query the schema of the main database. Create a mirror schema
  ** in the temporary database.
  */
  rc = execExecSql(db, 
      "SELECT 'CREATE TABLE vacuum_db.' || substr(sql,14,100000000) "

  ** transaction open on the vacuum database, but not on the main database.
  ** Open a btree level transaction on the main database. This allows a
  ** call to sqlite3BtreeCopyFile(). The main database btree level
  ** transaction is then committed, so the SQL level never knows it was
  ** opened for writing. This way, the SQL transaction used to create the
  ** temporary database never needs to be committed.
  */
  if( rc==SQLITE_OK ){
    u32 meta;
    int i;

    /* This array determines which meta meta values are preserved in the
    ** vacuum.  Even entries are the meta value number and odd entries
    ** are an increment to apply to the meta value after the vacuum.
    ** The increment is used to increase the schema cookie so that other
    ** connections to the same database will know to reread the schema.
    */
    static const unsigned char aCopy[] = {
       1, 1,    /* Add one to the old schema cookie */
       3, 0,    /* Preserve the default page cache size */
       5, 0,    /* Preserve the default text encoding */
       6, 0,    /* Preserve the user version */
    };

    assert( 1==sqlite3BtreeIsInTrans(pTemp) );
    assert( 1==sqlite3BtreeIsInTrans(pMain) );


    /* Copy Btree meta values */
    for(i=0; i<sizeof(aCopy)/sizeof(aCopy[0]); i+=2){
      rc = sqlite3BtreeGetMeta(pMain, aCopy[i], &meta);
      if( rc!=SQLITE_OK ) goto end_of_vacuum;
      rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]);
      if( rc!=SQLITE_OK ) goto end_of_vacuum;
    }

    rc = sqlite3BtreeCopyFile(pMain, pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pMain);
  }

end_of_vacuum:
  /* Restore the original value of db->flags */
  db->flags = saved_flags;

  /* Currently there is an SQL level transaction open on the vacuum
  ** database. No locks are held on any other files (since the main file
  ** was committed at the btree level). So it safe to end the transaction
  ** by manually setting the autoCommit flag to true and detaching the
  ** vacuum database. The vacuum_db journal file is deleted when the pager
  ** is closed by the DETACH.
  */
  db->autoCommit = 1;
  rc2 = execSql(db, "DETACH vacuum_db;");
  if( rc==SQLITE_OK ){
    rc = rc2;


  }
  if( zTemp ){
    sqlite3OsDelete(zTemp);
    sqliteFree(zTemp);
  }
  sqliteFree( zSql );
  sqlite3ResetInternalSchema(db, 0);
#endif

  return rc;
}

# 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 some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.51 2005/11/04 22:03:30 drh Exp $

# Make sure tclsqlite3 was compiled correctly.  Abort now with an
# error message if not.
#
if {[sqlite3 -tcl-uses-utf]} {
  if {"\u1234"=="u1234"} {
    puts stderr "***** BUILD PROBLEM *****"

    # Execute the TCL Script created in the above block. If
    # there are at least N IO operations performed by SQLite as
    # a result of the script, the Nth will fail.
    do_test $testname.$n.3 {
      set r [catch $::ioerrorbody msg]
      set ::go [expr {$::sqlite_io_error_pending<=0}]
      set s [expr $::sqlite_io_error_hit==0]
      # puts "$::sqlite_io_error_pending $r $msg"
      expr { ($s && !$r) || (!$s && $r) }
      # expr {$::sqlite_io_error_pending>0 || $r!=0}
    } {1}

    # If an IO error occured, then the checksum of the database should
    # be the same as before the script that caused the IO error was run.

# 2005 September 19
#
# 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.
#
# This file implements tests to verify that ticket #1512 is
# fixed.  
#

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

do_test tkt1512-1.1 {
  execsql {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,2);
    INSERT INTO t1 VALUES(3,4);
    SELECT * FROM t1
  }
} {1 2 3 4}
do_test tkt1512-1.2 {
  file size test.db
} {2048}
do_test tkt1512-1.3 {
  execsql {
    DROP TABLE t1;
  }
  file size test.db
} {2048}
do_test tkt1512-1.4 {
  execsql {
    VACUUM;
  }
  file size test.db
} {1024}


finish_test

#include <unistd.h>
#include <stdlib.h>


static int pagesize = 1024;
static int db = -1;
static int mxPage = 0;
static int perLine = 32;

static void out_of_memory(void){
  fprintf(stderr,"Out of memory...\n");
  exit(1);
}

static print_page(int iPg){
  unsigned char *aData;
  int i, j;
  aData = malloc(pagesize);
  if( aData==0 ) out_of_memory();
  lseek(db, (iPg-1)*pagesize, SEEK_SET);
  read(db, aData, pagesize);
  fprintf(stdout, "Page %d:\n", iPg);
  for(i=0; i<pagesize; i += perLine){
    fprintf(stdout, " %03x: ",i);
    for(j=0; j<perLine; j++){
      fprintf(stdout,"%02x ", aData[i+j]);
    }
    for(j=0; j<perLine; j++){
      fprintf(stdout,"%c", isprint(aData[i+j]) ? aData[i+j] : '.');
    }
    fprintf(stdout,"\n");
  }
  free(aData);
}