Add the xInMutex method to the os-layer switch for testing whether or not

mutexes are used correctly. (CVS 2851)

FossilOrigin-Name: a582b159595ff8d31c81e9b3044711d6590d3f0e

3 files changed, 28 insertions, 4 deletions

diff --git a/src/os.h b/src/os.h
index ca8ff318a..044708c03 100644
--- a/src/os.h
+++ b/src/os.h
@@ -217,12 +217,13 @@ extern struct sqlite3OsVtbl {
   int (*xSyncDirectory)(const char*);
   int (*xTempFileName)(char*);
 
-  int  (*xRandomSeed)(char*);
-  int  (*xSleep)(int ms);
-  int  (*xCurrentTime)(double*);
+  int (*xRandomSeed)(char*);
+  int (*xSleep)(int ms);
+  int (*xCurrentTime)(double*);
 
   void (*xEnterMutex)(void);
   void (*xLeaveMutex)(void);
+  int (*xInMutex)(void);
   void *(*xThreadSpecificData)(int);
 
   void *(*xMalloc)(int);
@@ -238,7 +239,7 @@ extern struct sqlite3OsVtbl {
 ** is intriniscally thread-safe.
 **
 ** External get/set access is only provided to the routines identified 
-** by the hash-defined SQLITE_OS_ROUTINE symbols.
+** by the following SQLITE_OS_ROUTINE symbols:
 */
 #define SQLITE_OS_ROUTINE_OPENREADWRITE   1
 #define SQLITE_OS_ROUTINE_OPENREADONLY    2
diff --git a/src/os_unix.c b/src/os_unix.c
index ab0d2c7b6..de7f0729c 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -1587,6 +1587,16 @@ static void unixLeaveMutex(){
 }
 
 /*
+** Return TRUE if we are currently within the mutex and FALSE if not.
+** This routine is intended for sanity checking only.  It is designed
+** for use in an assert() to verify that the mutex is held or not held
+** in certain routines.
+*/
+static int unixInMutex(){
+  return inMutex;
+}
+
+/*
 ** This function is called automatically when a thread exists to delete
 ** the threads SqliteTsd structure. 
 **
@@ -1706,6 +1716,7 @@ struct sqlite3OsVtbl sqlite3Os = {
   unixCurrentTime,
   unixEnterMutex,
   unixLeaveMutex,
+  unixInMutex,
   unixThreadSpecificData,
   genericMalloc,
   genericRealloc,
diff --git a/src/os_win.c b/src/os_win.c
index 5565beaa0..3ecacb9c8 100644
--- a/src/os_win.c
+++ b/src/os_win.c
@@ -991,6 +991,17 @@ static void winLeaveMutex(){
 }
 
 /*
+** Return TRUE if we are currently within the mutex and FALSE if not.
+** This routine is intended for sanity checking only.  It is designed
+** for use in an assert() to verify that the mutex is held or not held
+** in certain routines.
+*/
+static int winInMutex(){
+  return inMutex;
+}
+
+
+/*
 ** The following variable, if set to a non-zero value, becomes the result
 ** returned from sqlite3OsCurrentTime().  This is used for testing.
 */
@@ -1062,6 +1073,7 @@ struct sqlite3OsVtbl sqlite3Os = {
   winCurrentTime,
   winEnterMutex,
   winLeaveMutex,
+  winInMutex,
   winThreadSpecificData,
   genericMalloc,
   genericRealloc,