/*

 ** 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 # error "The MEMORY_DEBUG macro is obsolete.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_) */