1 | /* |
2 | ** 2007 August 28 |
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 the common header for all mutex implementations. |
14 | ** The sqliteInt.h header #includes this file so that it is available |
15 | ** to all source files. We break it out in an effort to keep the code |
16 | ** better organized. |
17 | ** |
18 | ** NOTE: source files should *not* #include this header file directly. |
19 | ** Source files should #include the sqliteInt.h file and let that file |
20 | ** include this one indirectly. |
21 | */ |
22 | |
23 | |
24 | /* |
25 | ** Figure out what version of the code to use. The choices are |
26 | ** |
27 | ** SQLITE_MUTEX_OMIT No mutex logic. Not even stubs. The |
28 | ** mutexes implementation cannot be overridden |
29 | ** at start-time. |
30 | ** |
31 | ** SQLITE_MUTEX_NOOP For single-threaded applications. No |
32 | ** mutual exclusion is provided. But this |
33 | ** implementation can be overridden at |
34 | ** start-time. |
35 | ** |
36 | ** SQLITE_MUTEX_PTHREADS For multi-threaded applications on Unix. |
37 | ** |
38 | ** SQLITE_MUTEX_W32 For multi-threaded applications on Win32. |
39 | */ |
40 | #if !SQLITE_THREADSAFE |
41 | # define SQLITE_MUTEX_OMIT |
42 | #endif |
43 | #if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP) |
44 | # if SQLITE_OS_UNIX |
45 | # define SQLITE_MUTEX_PTHREADS |
46 | # elif SQLITE_OS_WIN |
47 | # define SQLITE_MUTEX_W32 |
48 | # else |
49 | # define SQLITE_MUTEX_NOOP |
50 | # endif |
51 | #endif |
52 | |
53 | #ifdef SQLITE_MUTEX_OMIT |
54 | /* |
55 | ** If this is a no-op implementation, implement everything as macros. |
56 | */ |
57 | #define sqlite3_mutex_alloc(X) ((sqlite3_mutex*)8) |
58 | #define sqlite3_mutex_free(X) |
59 | #define sqlite3_mutex_enter(X) |
60 | #define sqlite3_mutex_try(X) SQLITE_OK |
61 | #define sqlite3_mutex_leave(X) |
62 | #define sqlite3_mutex_held(X) ((void)(X),1) |
63 | #define sqlite3_mutex_notheld(X) ((void)(X),1) |
64 | #define sqlite3MutexAlloc(X) ((sqlite3_mutex*)8) |
65 | #define sqlite3MutexInit() SQLITE_OK |
66 | #define sqlite3MutexEnd() |
67 | #define MUTEX_LOGIC(X) |
68 | #else |
69 | #define MUTEX_LOGIC(X) X |
70 | int sqlite3_mutex_held(sqlite3_mutex*); |
71 | #endif /* defined(SQLITE_MUTEX_OMIT) */ |
72 | |