xref: /sqlite-3.40.0/src/os_common.h (revision c04c54b8)
1 /*
2 ** 2004 May 22
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 ******************************************************************************
12 **
13 ** This file contains macros and a little bit of code that is common to
14 ** all of the platform-specific files (os_*.c) and is #included into those
15 ** files.
16 **
17 ** This file should be #included by the os_*.c files only.  It is not a
18 ** general purpose header file.
19 */
20 #ifndef _OS_COMMON_H_
21 #define _OS_COMMON_H_
22 
23 /*
24 ** At least two bugs have slipped in because we changed the MEMORY_DEBUG
25 ** macro to SQLITE_DEBUG and some older makefiles have not yet made the
26 ** switch.  The following code should catch this problem at compile-time.
27 */
28 #ifdef MEMORY_DEBUG
29 # error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
30 #endif
31 
32 /*
33 ** Macros for performance tracing.  Normally turned off.  Only works
34 ** on i486 hardware.
35 */
36 #ifdef SQLITE_PERFORMANCE_TRACE
37 
38 /*
39 ** hwtime.h contains inline assembler code for implementing
40 ** high-performance timing routines.
41 */
42 #include "hwtime.h"
43 
44 static sqlite_uint64 g_start;
45 static sqlite_uint64 g_elapsed;
46 #define TIMER_START       g_start=sqlite3Hwtime()
47 #define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
48 #define TIMER_ELAPSED     g_elapsed
49 #else
50 #define TIMER_START
51 #define TIMER_END
52 #define TIMER_ELAPSED     ((sqlite_uint64)0)
53 #endif
54 
55 /*
56 ** If we compile with the SQLITE_TEST macro set, then the following block
57 ** of code will give us the ability to simulate a disk I/O error.  This
58 ** is used for testing the I/O recovery logic.
59 */
60 #if defined(SQLITE_TEST)
61 extern int sqlite3_io_error_hit;
62 extern int sqlite3_io_error_hardhit;
63 extern int sqlite3_io_error_pending;
64 extern int sqlite3_io_error_persist;
65 extern int sqlite3_io_error_benign;
66 extern int sqlite3_diskfull_pending;
67 extern int sqlite3_diskfull;
68 #define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
69 #define SimulateIOError(CODE)  \
70   if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
71        || sqlite3_io_error_pending-- == 1 )  \
72               { local_ioerr(); CODE; }
local_ioerr()73 static void local_ioerr(){
74   IOTRACE(("IOERR\n"));
75   sqlite3_io_error_hit++;
76   if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
77 }
78 #define SimulateDiskfullError(CODE) \
79    if( sqlite3_diskfull_pending ){ \
80      if( sqlite3_diskfull_pending == 1 ){ \
81        local_ioerr(); \
82        sqlite3_diskfull = 1; \
83        sqlite3_io_error_hit = 1; \
84        CODE; \
85      }else{ \
86        sqlite3_diskfull_pending--; \
87      } \
88    }
89 #else
90 #define SimulateIOErrorBenign(X)
91 #define SimulateIOError(A)
92 #define SimulateDiskfullError(A)
93 #endif /* defined(SQLITE_TEST) */
94 
95 /*
96 ** When testing, keep a count of the number of open files.
97 */
98 #if defined(SQLITE_TEST)
99 extern int sqlite3_open_file_count;
100 #define OpenCounter(X)  sqlite3_open_file_count+=(X)
101 #else
102 #define OpenCounter(X)
103 #endif /* defined(SQLITE_TEST) */
104 
105 #endif /* !defined(_OS_COMMON_H_) */
106