<rdar://problem/13521159>

LLDB is crashing when logging is enabled from lldb-perf-clang. This has to do with the global destructor chain as the process and its threads are being torn down.

All logging channels now make one and only one instance that is kept in a global pointer which is never freed. This guarantees that logging can correctly continue as the process tears itself down.

llvm-svn: 178191

1 files changed, 32 insertions, 27 deletions

diff --git a/lldb/source/lldb-log.cpp b/lldb/source/lldb-log.cpp
index 162599068b9..7c78feddf1b 100644
--- a/lldb/source/lldb-log.cpp
+++ b/lldb/source/lldb-log.cpp
@@ -26,17 +26,21 @@ using namespace lldb_private;
 // 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 &
+
+static bool g_log_enabled = false;
+static Log * g_log = NULL;
+static Log *
 GetLog ()
 {
-    static LogSP g_log_sp;
-    return g_log_sp;
+    if (!g_log_enabled)
+        return NULL;
+    return g_log;
 }
 
 uint32_t
 lldb_private::GetLogMask ()
 {
-    LogSP log(GetLog ());
+    Log *log(GetLog ());
     if (log)
         return log->GetMask().Get();
     return 0;
@@ -49,15 +53,15 @@ lldb_private::IsLogVerbose ()
     return (mask & LIBLLDB_LOG_VERBOSE);
 }
 
-LogSP
+Log *
 lldb_private::GetLogIfAllCategoriesSet (uint32_t mask)
 {
-    LogSP log(GetLog ());
+    Log *log(GetLog ());
     if (log && mask)
     {
         uint32_t log_mask = log->GetMask().Get();
         if ((log_mask & mask) != mask)
-            return LogSP();
+            return NULL;
     }
     return log;
 }
@@ -65,7 +69,7 @@ lldb_private::GetLogIfAllCategoriesSet (uint32_t mask)
 void
 lldb_private::LogIfAllCategoriesSet (uint32_t mask, const char *format, ...)
 {
-    LogSP log(GetLogIfAllCategoriesSet (mask));
+    Log *log(GetLogIfAllCategoriesSet (mask));
     if (log)
     {
         va_list args;
@@ -78,7 +82,7 @@ lldb_private::LogIfAllCategoriesSet (uint32_t mask, const char *format, ...)
 void
 lldb_private::LogIfAnyCategoriesSet (uint32_t mask, const char *format, ...)
 {
-    LogSP log(GetLogIfAnyCategoriesSet (mask));
+    Log *log(GetLogIfAnyCategoriesSet (mask));
     if (log)
     {
         va_list args;
@@ -88,19 +92,19 @@ lldb_private::LogIfAnyCategoriesSet (uint32_t mask, const char *format, ...)
     }
 }
 
-LogSP
+Log *
 lldb_private::GetLogIfAnyCategoriesSet (uint32_t mask)
 {
-    LogSP log(GetLog ());
+    Log *log(GetLog ());
     if (log && mask && (mask & log->GetMask().Get()))
         return log;
-    return LogSP();
+    return NULL;
 }
 
 void
 lldb_private::DisableLog (const char **categories, Stream *feedback_strm)
 {
-    LogSP log(GetLog ());
+    Log *log(GetLog ());
 
     if (log)
     {
@@ -147,35 +151,35 @@ lldb_private::DisableLog (const char **categories, Stream *feedback_strm)
                 
             }
         }
+        log->GetMask().Reset (flag_bits);
         if (flag_bits == 0)
-            GetLog ().reset();
-        else
-            log->GetMask().Reset (flag_bits);
+            g_log_enabled = false;
     }
 
     return;
 }
 
-LogSP
+Log *
 lldb_private::EnableLog (StreamSP &log_stream_sp, uint32_t log_options, const char **categories, 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;
-    LogSP log(GetLog ());
-    if (log)
-        flag_bits = log->GetMask().Get();
+    if (g_log)
+        flag_bits = g_log->GetMask().Get();
     else
         flag_bits = 0;
 
     // Now make a new log with this stream if one was provided
     if (log_stream_sp)
     {
-        log.reset (new Log(log_stream_sp));
-        GetLog () = log;
+        if (g_log)
+            g_log->SetStream(log_stream_sp);
+        else
+            g_log = new Log(log_stream_sp);
     }
 
-    if (log)
+    if (g_log)
     {
         for (size_t i=0; categories[i] != NULL; ++i)
         {
@@ -211,14 +215,15 @@ lldb_private::EnableLog (StreamSP &log_stream_sp, uint32_t log_options, const ch
             {
                 feedback_strm->Printf("error: unrecognized log category '%s'\n", arg);
                 ListLogCategories (feedback_strm);
-                return log;
+                return g_log;
             }
         }
 
-        log->GetMask().Reset(flag_bits);
-        log->GetOptions().Reset(log_options);
+        g_log->GetMask().Reset(flag_bits);
+        g_log->GetOptions().Reset(log_options);
     }
-    return log;
+    g_log_enabled = true;
+    return g_log;
 }