Modified all logging calls to hand out shared pointers to make sure we

don't crash if we disable logging when some code already has a copy of the
logger. Prior to this fix, logs were handed out as pointers and if they were
held onto while a log got disabled, then it could cause a crash. Now all logs
are handed out as shared pointers so this problem shouldn't happen anymore.
We are also using our new shared pointers that put the shared pointer count
and the object into the same allocation for a tad better performance.

llvm-svn: 118319

1 files changed, 28 insertions, 32 deletions

diff --git a/lldb/source/lldb-log.cpp b/lldb/source/lldb-log.cpp
index 9237ee65520..c87bd0c8fd0 100644
--- a/lldb/source/lldb-log.cpp
+++ b/lldb/source/lldb-log.cpp
@@ -22,30 +22,21 @@ using namespace lldb;
 using namespace lldb_private;
 
 
-static Log *
-LogAccessor (bool get, StreamSP *stream_sp_ptr)
+// We want to avoid global constructors where code needs to be run so here we
+// control access to our static g_log_sp by hiding it in a singleton function
+// that will construct the static g_lob_sp the first time this function is 
+// called.
+static LogSP &
+GetLog ()
 {
-    static Log* g_log = NULL; // Leak for now as auto_ptr was being cleaned up
-                                // by global constructors before other threads
-                                // were done with it.
-    if (!get)
-    {
-        if (g_log)
-            delete g_log;
-        if (stream_sp_ptr)
-            g_log = new Log (*stream_sp_ptr);
-        else
-            g_log = NULL;
-    }
-
-    return g_log;
-
+    static LogSP g_log_sp;
+    return g_log_sp;
 }
 
 uint32_t
 lldb_private::GetLogMask ()
 {
-    Log *log = LogAccessor (true, NULL);
+    LogSP log(GetLog ());
     if (log)
         return log->GetMask().Get();
     return 0;
@@ -58,15 +49,15 @@ lldb_private::IsLogVerbose ()
     return (mask & LIBLLDB_LOG_VERBOSE);
 }
 
-Log *
+LogSP
 lldb_private::GetLogIfAllCategoriesSet (uint32_t mask)
 {
-    Log *log = LogAccessor (true, NULL);
+    LogSP log(GetLog ());
     if (log && mask)
     {
         uint32_t log_mask = log->GetMask().Get();
         if ((log_mask & mask) != mask)
-            return NULL;
+            return LogSP();
     }
     return log;
 }
@@ -74,7 +65,7 @@ lldb_private::GetLogIfAllCategoriesSet (uint32_t mask)
 void
 lldb_private::LogIfAllCategoriesSet (uint32_t mask, const char *format, ...)
 {
-    Log *log = GetLogIfAllCategoriesSet (mask);
+    LogSP log(GetLogIfAllCategoriesSet (mask));
     if (log)
     {
         va_list args;
@@ -87,7 +78,7 @@ lldb_private::LogIfAllCategoriesSet (uint32_t mask, const char *format, ...)
 void
 lldb_private::LogIfAnyCategoriesSet (uint32_t mask, const char *format, ...)
 {
-    Log *log = GetLogIfAnyCategoriesSet (mask);
+    LogSP log(GetLogIfAnyCategoriesSet (mask));
     if (log)
     {
         va_list args;
@@ -97,19 +88,19 @@ lldb_private::LogIfAnyCategoriesSet (uint32_t mask, const char *format, ...)
     }
 }
 
-Log *
+LogSP
 lldb_private::GetLogIfAnyCategoriesSet (uint32_t mask)
 {
-    Log *log = LogAccessor (true, NULL);
+    LogSP log(GetLog ());
     if (log && mask && (mask & log->GetMask().Get()))
         return log;
-    return NULL;
+    return LogSP();
 }
 
 void
 lldb_private::DisableLog (Args &args, Stream *feedback_strm)
 {
-    Log *log = LogAccessor (true, NULL);
+    LogSP log(GetLog ());
     uint32_t flag_bits;
 
     if (log)
@@ -148,7 +139,7 @@ lldb_private::DisableLog (Args &args, Stream *feedback_strm)
             
         }
         if (flag_bits == 0)
-            LogAccessor (false, NULL);
+            GetLog ().reset();
         else
             log->GetMask().Reset (flag_bits);
     }
@@ -156,20 +147,25 @@ lldb_private::DisableLog (Args &args, Stream *feedback_strm)
     return;
 }
 
-Log *
+LogSP
 lldb_private::EnableLog (StreamSP &log_stream_sp, uint32_t log_options, Args &args, Stream *feedback_strm)
 {
     // Try see if there already is a log - that way we can reuse its settings.
     // We could reuse the log in toto, but we don't know that the stream is the same.
     uint32_t flag_bits;
-    Log* log = LogAccessor (true, NULL);
+    LogSP log(GetLog ());
     if (log)
         flag_bits = log->GetMask().Get();
     else
         flag_bits = 0;
 
-    // Now make a new log with this stream.
-    log = LogAccessor (false, &log_stream_sp);
+    // Now make a new log with this stream if one was provided
+    if (log_stream_sp)
+    {
+        log = make_shared<Log>(log_stream_sp);
+        GetLog () = log;
+    }
+
     if (log)
     {
         bool got_unknown_category = false;