os_common.h.svn-base
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- /*
- ** 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.
- */
- /*
- ** 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- # error "The MEMORY_DEBUG macro is obsolete.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
- __inline__ unsigned long long int hwtime(void){
- unsigned long long int x;
- __asm__("rdtscnt"
- "mov %%edx, %%ecxnt"
- :"=A" (x));
- return x;
- }
- static unsigned long long int g_start;
- static unsigned int elapse;
- #define TIMER_START g_start=hwtime()
- #define TIMER_END elapse=hwtime()-g_start
- #define TIMER_ELAPSED elapse
- #else
- #define TIMER_START
- #define TIMER_END
- #define TIMER_ELAPSED 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(("IOERRn"));
- 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