xref: /sqlite-3.40.0/src/os_common.h (revision fdf6db12)
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29 # error "The MEMORY_DEBUG macro is obsolete.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 #ifdef SQLITE_DEBUG
33 # ifndef SQLITE_DEBUG_OS_TRACE
34 #   define SQLITE_DEBUG_OS_TRACE 0
35 # endif
36   int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
37 # define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
38 #else
39 # define OSTRACE(X)
40 #endif
41 
42 /*
43 ** Macros for performance tracing.  Normally turned off.  Only works
44 ** on i486 hardware.
45 */
46 #ifdef SQLITE_PERFORMANCE_TRACE
47 
48 /*
49 ** hwtime.h contains inline assembler code for implementing
50 ** high-performance timing routines.
51 */
52 #include "hwtime.h"
53 
54 static sqlite_uint64 g_start;
55 static sqlite_uint64 g_elapsed;
56 #define TIMER_START       g_start=sqlite3Hwtime()
57 #define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
58 #define TIMER_ELAPSED     g_elapsed
59 #else
60 #define TIMER_START
61 #define TIMER_END
62 #define TIMER_ELAPSED     ((sqlite_uint64)0)
63 #endif
64 
65 /*
66 ** If we compile with the SQLITE_TEST macro set, then the following block
67 ** of code will give us the ability to simulate a disk I/O error.  This
68 ** is used for testing the I/O recovery logic.
69 */
70 #ifdef SQLITE_TEST
71 int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
72 int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
73 int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
74 int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
75 int sqlite3_io_error_benign = 0;         /* True if errors are benign */
76 int sqlite3_diskfull_pending = 0;
77 int sqlite3_diskfull = 0;
78 #define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
79 #define SimulateIOError(CODE)  \
80   if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
81        || sqlite3_io_error_pending-- == 1 )  \
82               { local_ioerr(); CODE; }
83 static void local_ioerr(){
84   IOTRACE(("IOERR\n"));
85   sqlite3_io_error_hit++;
86   if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
87 }
88 #define SimulateDiskfullError(CODE) \
89    if( sqlite3_diskfull_pending ){ \
90      if( sqlite3_diskfull_pending == 1 ){ \
91        local_ioerr(); \
92        sqlite3_diskfull = 1; \
93        sqlite3_io_error_hit = 1; \
94        CODE; \
95      }else{ \
96        sqlite3_diskfull_pending--; \
97      } \
98    }
99 #else
100 #define SimulateIOErrorBenign(X)
101 #define SimulateIOError(A)
102 #define SimulateDiskfullError(A)
103 #endif
104 
105 /*
106 ** When testing, keep a count of the number of open files.
107 */
108 #ifdef SQLITE_TEST
109 int sqlite3_open_file_count = 0;
110 #define OpenCounter(X)  sqlite3_open_file_count+=(X)
111 #else
112 #define OpenCounter(X)
113 #endif
114 
115 #endif /* !defined(_OS_COMMON_H_) */
116