Break up the mutex implementation into separate source files, one

each for unix, w32, and os2. (CVS 4312)

FossilOrigin-Name: fc5cd71aef5ac194f51d73350d773d532020967e

src/mutex.h

@@ -0,0 +1,82 @@
+/*
+** 2007 August 28
+**
+** 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 the common header for all mutex implementations.
+** The sqliteInt.h header #includes this file so that it is available
+** to all source files.  We break it out in an effort to keep the code
+** better organized.
+**
+** NOTE:  source files should *not* #include this header file directly.
+** Source files should #include the sqliteInt.h file and let that file
+** include this one indirectly.
+**
+** $Id: mutex.h,v 1.1 2007/08/28 16:34:43 drh Exp $
+*/
+
+
+#ifdef SQLITE_MUTEX_APPDEF
+/*
+** If SQLITE_MUTEX_APPDEF is defined, then this whole module is
+** omitted and equivalent functionality must be provided by the
+** application that links against the SQLite library.
+*/
+#else
+/*
+** Figure out what version of the code to use.  The choices are
+**
+**   SQLITE_MUTEX_NOOP         For single-threaded applications that
+**                             do not desire error checking.
+**
+**   SQLITE_MUTEX_NOOP_DEBUG   For single-threaded applications with
+**                             error checking to help verify that mutexes
+**                             are being used correctly even though they
+**                             are not needed.  Used when SQLITE_DEBUG is
+**                             defined on single-threaded builds.
+**
+**   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
+**
+**   SQLITE_MUTEX_WIN          For multi-threaded applications on Win32.
+**
+**   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
+*/
+#define SQLITE_MUTEX_NOOP 1   /* The default */
+#if defined(SQLITE_DEBUG) && !SQLITE_THREADSAFE
+# undef SQLITE_MUTEX_NOOP
+# define SQLITE_MUTEX_NOOP_DEBUG
+#endif
+#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_UNIX
+# undef SQLITE_MUTEX_NOOP
+# define SQLITE_MUTEX_PTHREADS
+#endif
+#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_WIN
+# undef SQLITE_MUTEX_NOOP
+# define SQLITE_MUTEX_WIN
+#endif
+#if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && OS_OS2
+# undef SQLITE_MUTEX_NOOP
+# define SQLITE_MUTEX_OS2
+#endif
+
+#ifdef SQLITE_MUTEX_NOOP
+/*
+** If this is a no-op implementation, implement everything as macros.
+*/
+#define sqlite3_mutex_alloc(X)    ((sqlite3_mutex*)8)
+#define sqlite3_mutex_free(X)
+#define sqlite3_mutex_enter(X)
+#define sqlite3_mutex_try(X)      SQLITE_OK
+#define sqlite3_mutex_leave(X)
+#define sqlite3_mutex_held(X)     1
+#define sqlite3_mutex_notheld(X)  1
+#endif
+
+#endif /* SQLITE_MUTEX_APPDEF */