/*

** 2004 May 22

**

** 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 contains macros and a little bit of code that is common to

** all of the platform-specific files (os_*.c) and is #included into those

** files.

**

** This file should be #included by the os_*.c files only.  It is not a

** general purpose header file.

**

** $Id: os_common.h,v 1.37 2008/05/29 20:22:37 shane Exp $

*/

#ifndef _OS_COMMON_H_

#define _OS_COMMON_H_

/*

** At least two bugs have slipped in because we changed the MEMORY_DEBUG

** macro to SQLITE_DEBUG and some older makefiles have not yet made the

** switch.  The following code should catch this problem at compile-time.

*/

#ifdef MEMORY_DEBUG

# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."

#endif

/*

 * When testing, this global variable stores the location of the

 * pending-byte in the database file.

 */

#ifdef SQLITE_TEST

unsigned int sqlite3_pending_byte = 0x40000000;

#endif

#ifdef SQLITE_DEBUG

int sqlite3OSTrace = 0;

#define OSTRACE1(X)         if( sqlite3OSTrace ) sqlite3DebugPrintf(X)

#define OSTRACE2(X,Y)       if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y)

#define OSTRACE3(X,Y,Z)     if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z)

#define OSTRACE4(X,Y,Z,A)   if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A)

#define OSTRACE5(X,Y,Z,A,B) if( sqlite3OSTrace ) sqlite3DebugPrintf(X,Y,Z,A,B)

#define OSTRACE6(X,Y,Z,A,B,C) \

    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C)

#define OSTRACE7(X,Y,Z,A,B,C,D) \

    if(sqlite3OSTrace) sqlite3DebugPrintf(X,Y,Z,A,B,C,D)

#else

#define OSTRACE1(X)

#define OSTRACE2(X,Y)

#define OSTRACE3(X,Y,Z)

#define OSTRACE4(X,Y,Z,A)

#define OSTRACE5(X,Y,Z,A,B)

#define OSTRACE6(X,Y,Z,A,B,C)

#define OSTRACE7(X,Y,Z,A,B,C,D)

#endif

/*

** Macros for performance tracing.  Normally turned off.  Only works

** on i486 hardware.

*/

#ifdef SQLITE_PERFORMANCE_TRACE

/* 

** hwtime.h contains inline assembler code for implementing 

** high-performance timing routines.

*/

#include "hwtime.h"

static sqlite_uint64 g_start;

static sqlite_uint64 g_elapsed;

#define TIMER_START       g_start=sqlite3Hwtime()

#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start

#define TIMER_ELAPSED     g_elapsed

#else

#define TIMER_START

#define TIMER_END

#define TIMER_ELAPSED     ((sqlite_uint64)0)

#endif

/*

** 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;            /* Total number of I/O Errors */

int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */

int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */

int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */

int sqlite3_io_error_benign = 0;         /* True if errors are benign */

int sqlite3_diskfull_pending = 0;

int sqlite3_diskfull = 0;

#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)

#define SimulateIOError(CODE)  \

  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \

       || sqlite3_io_error_pending-- == 1 )  \

              { local_ioerr(); CODE; }

static void local_ioerr(){

  IOTRACE(("IOERR\n"));

  sqlite3_io_error_hit++;

  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;

}

#define SimulateDiskfullError(CODE) \

   if( sqlite3_diskfull_pending ){ \

     if( sqlite3_diskfull_pending == 1 ){ \

       local_ioerr(); \

       sqlite3_diskfull = 1; \

       sqlite3_io_error_hit = 1; \

       CODE; \

     }else{ \

       sqlite3_diskfull_pending--; \

     } \

   }

#else

#define SimulateIOErrorBenign(X)

#define SimulateIOError(A)

#define SimulateDiskfullError(A)

#endif

/*

** When testing, keep a count of the number of open files.

*/

#ifdef SQLITE_TEST

int sqlite3_open_file_count = 0;

#define OpenCounter(X)  sqlite3_open_file_count+=(X)

#else

#define OpenCounter(X)

#endif

#endif /* !defined(_OS_COMMON_H_) */